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Yan F, Ye Z, Cao B, Wang F. Mechanical properties of reaction mediums in permeable reactive barriers. Sci Total Environ 2024; 926:171868. [PMID: 38521278 DOI: 10.1016/j.scitotenv.2024.171868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 03/16/2024] [Accepted: 03/19/2024] [Indexed: 03/25/2024]
Abstract
The mechanical properties of reaction media in permeable reactive barriers (PRB) is vital in geoenvironmental applications. Bentonite, activated carbon and zeolite, recognized for their excellent adsorption capabilities, are employed as the main reaction media in PRB for the treatment of contaminated underground water. The compaction test and the undrained and unconsolidated triaxial test were carried out to investigate the compression and shear strength of the activated carbon-zeolite mixture and activated carbon-bentonite mixture at various composition ratios. The impact of compaction degree on samples' shear strength was analyzed. The influence of different composition ratios on the mechanical properties and the permeability of each reaction medium were also evaluated. The results show that the mechanical performance of most activated carbon-zeolite (AZs) is not satisfactory compared to natural soil and activated carbon-bentonite mixtures. Activated carbon‑sodium bentonite (ANBs) and activated carbon‑calcium bentonite (ACBs) present similar compaction characteristics and shear properties. In ANBs and ACBs, the cohesion of mixes with a mass ratio of 1:2 (ANB2 and ACB2) was found lower than that of mixes with mass ratios of 1:1 (ANB1 and ACB1) and 1:3 (ANB3 and ACB3). And in most ANB and ACB mixes, 100 % compaction produced higher moisture content and higher friction angle, but lower cohesion, compared to 92 % compaction degree. And the shear strength behavior of ANBs is dominated by both bentonite and activated carbon. The permeability of ACB1, AZ3 and ACB1-sand are at 1.31 × 10-6 m/s, 1.37 × 10-6 m/s and 7.72 × 10-7 m/s, respectively. These results provide valuable insights into the selection and optimization of reaction media for PRBs in geoenvironmental engineering applications.
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Affiliation(s)
- Fangmin Yan
- Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing 210096, China.
| | - Zijun Ye
- Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing 210096, China.
| | - Benyi Cao
- School of Sustainability, Civil and Environmental Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK.
| | - Fei Wang
- Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing 210096, China.
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Kanagaraj B, N A, R SR, Andrushia D, Lubloy E. Practicability and environmental impact assessment of synthetic fibre reinforced polymer (SFRP) stirrups in reinforced concrete beams. Heliyon 2024; 10:e28149. [PMID: 38560272 PMCID: PMC10979163 DOI: 10.1016/j.heliyon.2024.e28149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 03/07/2024] [Accepted: 03/11/2024] [Indexed: 04/04/2024] Open
Abstract
In this study, the objective is to explore the practicability of incorporating synthetic fibre reinforced polymer (SFRP) stirrups into reinforced concrete beams. This investigation revolves around evaluating their effectiveness from two key perspectives: their structural performance and environmental impact. To accomplish this, four set of specimens were prepared, each integrating SFRP stirrups, and testing them under a rigorous three-point bending load test. The structural performance analysis entails a comprehensive examination on the critical design factors such as: the load-deflection relationship and the contribution these SFRP stirrups to improve the ductility performance, flexural stiffness, deformability factor, flexural toughness and energy absorption capacity. The findings of this study indicate that the SFRP stirrups exhibit commendable shear capacity, meeting the necessary requirements, and simultaneously demonstrate satisfactory ductility. It is determined, that the optimal design for these SFRP stirrups involves utilizing narrow and thin stirrups placed at relatively larger intervals. Furthermore, this research delves into assessing the environmental impact of incorporating SFRP stirrups. This assessment enables us to comprehensively evaluate the environmental implications of the entire life cycle of these stirrups in structural beam. Moreover, the analysis reveals that, SFRP stirrups yields lower environmental impacts compared to their steel counterparts, they still provide valuable insights into the overall sustainability considerations within the context of reinforced concrete structures.
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Affiliation(s)
- Balamurali Kanagaraj
- Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India
| | - Anand N
- Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India
| | - Samuvel raj R
- Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India
| | - Diana Andrushia
- Department of Electronics and Communication Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India
| | - Eva Lubloy
- Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, Hungary
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Wu W, Wang C, Jiang H. Impacts of microplastic contamination on the rheology properties of sediments in a eutrophic shallow lake. Environ Pollut 2024; 346:123545. [PMID: 38346632 DOI: 10.1016/j.envpol.2024.123545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/17/2024] [Accepted: 02/09/2024] [Indexed: 02/23/2024]
Abstract
Microplastic (MP) contamination is a growing global concern, with lake sediments serving as a significant sink for MP due to both anthropogenic and natural activities. Given the increasing evidence of MP accumulation in sediments, it was crucial to assess their influence on sediment erosion resistance, which directly affected sediment resuspension. To fill this gap, this study focused on the effect of MP on the sediments rheological properties. After 60-day experiments, it was found that MP addition into sediments reduced sediment viscosity, yield stress, and flow point shear stress. Meanwhile, MPs also significantly altered sediment properties and extracellular polymer composition. MP addition reduced extracellular polymeric substances production and cation exchange capacity, which then worked together and led to a weak sediment structure. Seemingly, MPs changed fluid sediment characteristics and caused stronger fluidity under less shear force. Consequently, the accumulation of MP might facilitate the resuspension of sediments under smaller wind and wave disturbances. This study provided novel insights into the direct impact of MPs on sediment physical properties using rheology, thereby enhancing our understanding of the environmental behavior of MPs in lake ecosystems.
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Affiliation(s)
- Wenbin Wu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chunliu Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Helong Jiang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China; College of Nanjing, University of Chinese Academy of Sciences, Nanjing, 211135, China.
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Yu H, Xia Y, Liu X, Chen H, Jin Z, Wang Z. Preparation of reed fibers reinforced graft-modified starch-based adhesives based on quantum mechanical simulation and molecular dynamics simulation. Int J Biol Macromol 2024; 262:129802. [PMID: 38296149 DOI: 10.1016/j.ijbiomac.2024.129802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/19/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024]
Abstract
Starch is a biomass polymer material with a high yield and comprehensive source. It is used as a raw material for preparing adhesives because of its highly active hydroxyl group. However, poor adhesion and water resistance hinder the application of starch-based adhesives (SBAs). Based on this, the starch was modified through graft copolymerization with itaconic acid as a cross-linking agent, methyl methacrylate and methyl acrylate as copolymers. Additionally, reed fibers were synergistically modified with polydopamine deposition to prepare an environmentally friendly SBA used in plywood production. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TG) demonstrate that copolymerization of methyl methacrylate and methyl acrylate with starch improves the shear strength, water resistance, and thermal stability of the SBA. Compared to unmodified starch, the modified SBA exhibits a 129 % increase in dry strength and achieves a wet strength of 1.36 MPa. Fukui function, Frontier orbit theory, and molecular dynamics simulation have shown that itaconic acid promotes the copolymerization of starch and acrylate monomers. The modified starch has fewer hydrogen bonds, less order, and a denser macromolecular network structure, which provides a reference for studying the molecular interaction mechanisms of SBAs.
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Affiliation(s)
- Hongjian Yu
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China; College of Light Industry and Textile, Qiqihar University, Qiqihar, Heilongjiang 161000, China
| | - Ying Xia
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China.
| | - Xueting Liu
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Haozhe Chen
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Zhixiang Jin
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Zhichao Wang
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
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Gallage C, Jayakody S, Abeykoon T, Biyanvilage D, Rajapakse J. A laboratory-based test procedure for the investigation of slaking-induced changes in geotechnical properties of tailing dam embankment materials. Heliyon 2024; 10:e26489. [PMID: 38420417 PMCID: PMC10901013 DOI: 10.1016/j.heliyon.2024.e26489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/12/2024] [Accepted: 02/14/2024] [Indexed: 03/02/2024] Open
Abstract
Slaking is a process of material parameters alteration resulting from wetting-drying cycles, changes in overburden stress, and chemical interactions. Tailings Storage Facilities (TSF) constructed with materials prone to slaking may experience breaches, especially during the post-closure period, due to the deterioration of shear strength and permeability characteristics. Rockfill materials, particularly those containing clay components, can undergo various forms of crack formation, leading to disintegration as a result of wetting-drying cycles, stress increments, and intense compaction. However, there are currently limited methodologies available for replicating such material alterations on a laboratory scale. Therefore, a new large-scale laboratory testing approach has been designed to simulate variations in wetting-drying cycles, humidity, and overburden pressure, enabling the prediction of the slaking potential of TSF construction materials. This novel methodology replicates field drying-wetting cycles and variations in humidity and overburden stress in a controlled environment, allowing for the estimation of the deterioration of shear strength and permeability characteristics in rockfill materials.
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Affiliation(s)
- Chaminda Gallage
- School of Civil and Environmental Engineering, Queensland University of Technology, Australia
| | - Shiran Jayakody
- School of Civil and Environmental Engineering, Queensland University of Technology, Australia
| | - Tharindu Abeykoon
- School of Civil and Environmental Engineering, Queensland University of Technology, Australia
| | | | - Jay Rajapakse
- School of Civil and Environmental Engineering, Queensland University of Technology, Australia
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Alijani S, Fotovat F, Rezaei Soufi L, Alafchi B, Mohammadkhani MH. Shear bond strength of orthodontic brackets to specimens fabricated from temporary restorative materials by 3D-printing, CAD/CAM technology, and the conventional technique after surface treatment by sandblasting and laser. Int Orthod 2023; 21:100790. [PMID: 37421919 DOI: 10.1016/j.ortho.2023.100790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/12/2023] [Accepted: 06/23/2023] [Indexed: 07/10/2023]
Abstract
OBJECTIVES This study assessed the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets to specimens fabricated from polymethyl methacrylate (PMMA) temporary restorative material by 3D-printing, computer-aided design/computer-aided manufacturing (CAD/CAM) technology, and the conventional technique, after surface treatment by sandblasting and laser. MATERIAL AND METHODS In this in vitro study, 60 disc-shaped specimens with 8mm diameter and 1mm height were fabricated from PMMA temporary restorative material by 3D-printing, CAD/CAM, and the conventional technique. In each group (n=20), half of the specimens were sandblasted while the other half underwent Er,Cr:YSGG laser irradiation. Brackets were bonded to the specimens and underwent thermocycling followed by SBS testing. Data were analysed by one-way ANOVA, independent t-test, and LSD test (alpha=0.05). RESULTS A significant difference existed among the three fabrication methods in SBS in both laser (P<0.001) and sandblasting (P<0.001) surface treatment groups. In laser group, the mean SBS of CAD/CAM (P=0.000) and conventional (P=0.000) groups was significantly lower than that of 3D-printing group. In sandblasting group, the SBS of CAD/CAM group was significantly lower than 3D-printing (P=0.000) and conventional (P=0.000) groups. The mean SBS of laser-treated specimens was significantly higher than sandblasted specimens in 3D-printing group (P=0.000), and significantly lower than sandblasted specimens in the conventional group (P=0.000). A significantly higher SBS was obtained by laser treatment compared with sandblasting irrespective of the fabrication method (P=0.000). CONCLUSION The highest SBS of SS orthodontic brackets to temporary restorative material was recorded for 3D-printed specimens treated by Er,Cr:YSGG laser irradiation.
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Affiliation(s)
- Sara Alijani
- Department of Orthodontics, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Farnoush Fotovat
- Department of Prosthodontics, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Loghman Rezaei Soufi
- Department of Restorative Dentistry, Dental Research Center, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Behnaz Alafchi
- Modeling of Noncommunicable Diseases Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
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Duan Z, Wang J, Yan X, Song K, Zheng L, Zhang M. Study on the structure and strength characteristics of loess under the action of sodium sulfate. Environ Sci Pollut Res Int 2023; 30:125609-125627. [PMID: 38006484 DOI: 10.1007/s11356-023-31038-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 11/08/2023] [Indexed: 11/27/2023]
Abstract
In recent years, with the increasing frequency of human engineering activities, the phenomenon of sodium sulfate erosion has been widely observed in the Loess Plateau. This not only leads to difficulties in land reclamation but also affects human health, posing a significant risk to the investment environment in the Northwest region of China. In this study, three types of loess were treated with sodium sulfate to prepare remolded soil samples with salt content levels of 0%, 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%. Observations and tests were conducted at multiple scales. The results indicate significant differences in the structural characteristics of the three types of loess under the influence of sodium sulfate. The higher the salt content in the loess, the greater the degree of structural damage. Subsequently, macroscopic mechanical properties were determined through direct shear tests, and it was found that as the salt content in the loess increased, the strength decreased. The resulting macroscopic mechanical properties showed a strong correlation with the microstructural characteristics. This study provides valuable insights for soil and water conservation and geological disaster prevention in the Loess Plateau region.
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Affiliation(s)
- Zhao Duan
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, China
- Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an, 710054, China
| | - Jiaxuan Wang
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, China.
- Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an, 710054, China.
| | - Xusheng Yan
- Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Department of Geotechnical Engineering, Tongji University, Shanghai, 200092, China
| | - Kun Song
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, China
- Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an, 710054, China
| | - Licai Zheng
- Sanying Precision Instruments Co., Ltd, Tianjin, 300000, China
| | - Mengmeng Zhang
- Sanying Precision Instruments Co., Ltd, Tianjin, 300000, China
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Xiao G, Zhang D, Xu G, Jiang G, Yin L. Based on bound water characteristics study of microporosity characteristics and mechanical properties evolution of copper-contaminated laterite. Environ Sci Pollut Res Int 2023; 30:121548-121557. [PMID: 37955727 DOI: 10.1007/s11356-023-30998-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/06/2023] [Indexed: 11/14/2023]
Abstract
The potential impact of heavy metal ion infiltration on macroscopic and microscopic soil properties is a subject of academic interest. Laterite has an extensive distribution in southern China and is extensively utilized as a vertical containment wall for landfills. Consequently, there is a need to investigate how heavy metal ions affect laterite's microstructure and mechanical properties. To examine the impact of Cu2+ on laterite's microporous characteristics and mechanical properties, laboratory tests were conducted on the permeability, shear strength, microporous characteristics, and strong absorbed water content of Cu2+-contaminated laterite. The results show that Cu2+ hydrolysis generates an acidic environment, which leads to erosion of the cementing substance between the laterite particles, increasing the laterite's porosity and decreasing the soil's cohesive strength, thus affecting the shear strength and permeability of the laterite. When the concentration of Cu2+ is 5.0 g/L, the laterite demonstrated the most significant decrease in shear strength, 43.01%, while the permeability coefficient increased from 3.24 × 10-8 cm/s to 1.32 × 10-7 cm/s. Meanwhile, Cu2+ changes the content of strong absorbed water in laterite. The change of strong absorbed water content will affect the Van der Waals between laterite particles, promote the evolution of soil micropore structure, and lead to a decrease in the proportion of intra-aggregate pores (d < 1 μm) and an increase in the proportion of inter-aggregate pores (1 μm < d < 10 μm), which in turn affects the macroscopic shear strength and permeability. This study has improved our understanding of the mechanisms underlying the microporosity and mechanical property evolution of laterite when subjected to heavy metal attack.
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Affiliation(s)
- Guiyuan Xiao
- Guangxi Key Laboratory of Geotechnical Mechanics and Engineering, Guilin University of Technology, Guilin, 541004, China.
| | - Dajin Zhang
- School of Engineering, China University of Geosciences, Wuhan, 430000, China
| | - Guangli Xu
- School of Engineering, China University of Geosciences, Wuhan, 430000, China
| | - Guanghui Jiang
- China Construction Road & Bridge Group Limited, Beijing, China
| | - Le Yin
- The Guangxi Zhuang Autonomous Region Company of China National Tobacco Corporation, Liuzhou, China
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Liu M, Xu X, Liu Q, Zhang K, Xin P. Effect of various Er:YAG laser conditioning energies on dentin surface: micromorphological investigation and dentin-resin shear bond strength test. Lasers Med Sci 2023; 38:242. [PMID: 37878132 DOI: 10.1007/s10103-023-03915-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 10/19/2023] [Indexed: 10/26/2023]
Abstract
The aim of this study is to assess the influence of various Er:YAG laser energies on dentin surface micromorphology and dentine-resin shear bond strength (SBS). Eighty dentin specimens were prepared and divided randomly into ten groups: control group (CG), phosphoric acid-etched group (AG), four laser-conditioned groups treated with various pulse energies of 40, 60, 80, and 100 mJ (L40, L60, L80, L100), and four laser-conditioned acid-etched groups (LA40, LA60, LA80, LA100). Two specimens from each group underwent scanning electron microscopy examination, while the remaining six were subjected to the dentin-resin SBS test. Statistical analyses included Welch's analysis of variance (ANOVA), followed by post hoc Tamhane's T2 multiple comparisons test, Pearson's correlation, and Fisher's exact test. Pulse energies of 60, 80, and 100 mJ fully exposed the dentin tubule orifices, although 100 mJ lead to microcracks. Laser-conditioned surfaces exhibited smaller tubule diameters compared to acid-etched surfaces, and tubule diameters positively correlated with dentin-resin SBS. Laser-conditioned groups showed lower SBS values, while laser-conditioned acid-etched groups demonstrated higher SBS values. No significant relationship was observed between dentin surface roughness and SBS. The range of laser energies used for dentin conditioning had limited effects on SBS or failure modes. Laser conditioning with energies ranging from 40 to 100 mJ effectively removes the smear layer from the dentin surface. However, to enhance dentin-resin bond strength, further acid etching of the laser-conditioned surface is necessary.
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Affiliation(s)
- Min Liu
- Department of Stomatology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China
- Department of Stomatology, Taiyuan Central Hospital, Taiyuan Central Hospital of Shanxi Medical University, Taiyuan, 030009, China
| | - Xin Xu
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, 030000, China
| | - Qingmei Liu
- Department of Stomatology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Kuanshou Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, 030006, China
| | - Pengfei Xin
- Department of Stomatology, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China.
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Garg A, Gadi VK, Zhu HH, Sarmah AK, Sreeja P, Sekharan S. A geotechnical perspective on soil-termite interaction: Role of termites in unsaturated soil properties. Sci Total Environ 2023; 895:164864. [PMID: 37331385 DOI: 10.1016/j.scitotenv.2023.164864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 05/24/2023] [Accepted: 06/11/2023] [Indexed: 06/20/2023]
Abstract
The soil-insect interaction has gathered significant attention in the recent years due to its contribution to bio-cementation. Termites, as a group of cellulose-eating insects, alter physical (texture) and chemical (chemical composition) properties of soil. Conversely, physico-chemical properties of soil also influence termite activities. It is vital to understand the soil-termite interaction and their influence on hydraulic properties and shear strength of soil, which are related to a series of geotechnical engineering problems such as ground water recharge, runoff, erosion and stability of slopes. In this study, an attempt has been made to review the latest developments and research gaps in our understanding of soil-termite interaction within the context of geo-environmental engineering. The hydraulic properties and shear strength of termite modified soil were discussed with respect to soil texture, density and physico-chemical composition. The incorporation of hysteresis effect of soil water characteristic curve, and spatio-temporal variations of hydraulic conductivity and shear strength of termite modified soil is proposed to be considered in geotechnical engineering design and construction. Finally, the challenges and future trends in this research area are presented. The expertise from both geotechnical engineering and entomology is needed to plan future research with an aim to promote use of termites as maintenance engineers in geotechnical infrastructure.
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Affiliation(s)
- Ankit Garg
- Department of Civil and Environmental Engineering, Shantou University, China.
| | - Vinay Kumar Gadi
- Department of Civil and Environmental Engineering, Cardiff University, United Kingdom.
| | - Hong-Hu Zhu
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China.
| | - Ajit K Sarmah
- Department of Civil & Environmental Engineering, The Faculty of Engineering, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| | - P Sreeja
- Department of Civil Engineering, Indian Institute of Technology Guwahati, India.
| | - Sreedeep Sekharan
- Department of Civil Engineering, Indian Institute of Technology Guwahati, India.
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Sheikh F, Alshameri B, Maqsood Z, Haider A, Hassan J. PET waste management in Pakistan through use of PET shreds as additive in backfill soil. Environ Monit Assess 2023; 195:1239. [PMID: 37736797 DOI: 10.1007/s10661-023-11832-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 09/04/2023] [Indexed: 09/23/2023]
Abstract
The management of waste plastic bottles is one of the major environmental challenges in the world. Plastic bottles are composed of polyethylene terephthalate (PET), which is non-biodegradable, resulting in environmental problems. Various studies have been carried out on the use of waste PET bottles in the form of custom-made strips as a stabilizer. However, no significant research has been carried out on the use of waste PET bottle shreds already available in the market. These shreds do not require any special technology or arrangement for bulk production. In this study, the shear strength of low plastic silty clay was improved using locally available PET shreds, and their prospective application in the backfill soil was investigated. Standard Proctor tests and direct shear tests were conducted on soil stabilized with three different sizes of plastic shreds (2 mm, 6 mm, and 10 mm) in four different percentages (1%, 3%, 5%, and 10%). Findings revealed that adding PET shreds in 1% content improves the shear strength characteristics. However, the shear strength parameters decrease with further increase in PET shred content. Therefore, PET shreds in 1% content can be added in backfill soil to improve its shear strength. Pakistan needs to construct 0.77 million housing units annually to keep up with its population growth. The statistics of seven major cities of Pakistan show that the PET waste management issue of Pakistan can be resolved by using PET shreds as a backfill additive in only 32% of the new houses required to be constructed.
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Affiliation(s)
- Fawad Sheikh
- National University of Sciences and Technology, Islamabad, Pakistan
| | - Badee Alshameri
- National University of Sciences and Technology, Islamabad, Pakistan.
| | - Zain Maqsood
- National University of Sciences and Technology, Islamabad, Pakistan
| | - Abbas Haider
- National University of Sciences and Technology, Islamabad, Pakistan
| | - Jawad Hassan
- National University of Sciences and Technology, Islamabad, Pakistan
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Biglar N, Chaychi Raghimi E, Sadighian S, Karamitanha F, Zajkani E, Nourian A. Effect of incorporating silica-hydroxyapatite-silver hybrid nanoparticles into the resin-modified glass ionomer on the adhesive remnant index score and shear bond strength of orthodontic metal brackets: An in vitro study. Int Orthod 2023; 21:100761. [PMID: 37244178 DOI: 10.1016/j.ortho.2023.100761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 04/15/2023] [Accepted: 04/29/2023] [Indexed: 05/29/2023]
Abstract
OBJECTIVES This study aimed to assess the effect of addition of silica-hydroxyapatite-silver (Si-HA-Ag) hybrid nanoparticles to light-cure glass ionomer (GI) on shear bond strength (SBS) of metal brackets bonded with this adhesive and the adhesive remnant index (ARI) score. MATERIAL AND METHODS In this in vitro experimental study, 50 sound extracted premolars were assigned to 5 groups (n=10) for orthodontic metal bracket bonding with BracePaste® composite, Fuji ORTHO™ pure resin modified GI (RMGI), and RMGI reinforced with 2wt%, 5wt% and 10wt% Si-HA-Ag nanoparticles. The SBS of brackets was measured by a universal testing machine. Debonded specimens were inspected under a stereomicroscope at×10 magnification to determine the ARI score. Data were analyzed by one-way ANOVA, Scheffe test, Chi-square test, and Fisher's exact test (alpha=0.05). RESULTS The maximum mean SBS was recorded in BracePaste® composite followed by 2% RMGI, 0% RMGI, 5% RMGI and 10% RMGI. Only the difference between the BracePaste® composite and 10% RMGI was significant in this regard (P=0.006). The groups were not significantly different regarding the ARI scores (P=0.665). All the SBS values were within the clinically acceptable range. CONCLUSION Addition of 2wt% and 5wt% Si-HA-Ag hybrid nanoparticles to RMGI as orthodontic adhesive caused no significant change in SBS of orthodontic metal brackets while addition of 10wt% hybrid nanoparticles significantly decreased the SBS. Nonetheless, all the SBS values were within the clinically acceptable range. Addition of hybrid nanoparticles had no significant effect on the ARI score.
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Affiliation(s)
- Nazila Biglar
- School of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran
| | | | - Somayeh Sadighian
- Department of Pharmaceutical Biomaterials, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Farzaneh Karamitanha
- Department of Social Medicine, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Elham Zajkani
- Department of Restorative Dentistry, Faculty of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Azin Nourian
- Department of Orthodontics, School of Dentistry, Zanjan University of Medical Sciences, Zanjan, Iran.
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13
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Bansal D, Ramana GV, Datta M, Gupta G. Characterization of MSW incineration bottom ash for use as structural fill in reinforced soil structures: Geoenvironmental, geotechnical and economical assessment. Waste Manag 2023; 168:344-353. [PMID: 37343441 DOI: 10.1016/j.wasman.2023.06.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 06/01/2023] [Accepted: 06/15/2023] [Indexed: 06/23/2023]
Abstract
The study presents the geoenvironmental and geotechnical characterization of MSW incineration bottom ash (IBA) and examines its reuse as structural fill in reinforced soil structures (RSS).The suitability of reuse has been assessed with regard to international regulatory standards. The prime focus of the work remains on evaluating the pullout response of geosynthetic reinforcements through IBA fill to determine the interaction coefficient, which has never been addressed in the literature. The economic viability of using IBA instead of locally available river sand for a 12 m high MSE wall is also established. The column leaching test results confirm that IBA can be utilized in RSS with suitable design measures. The geotechnical investigation shows that IBA is a well-graded, non-plastic lightweight material with adequate drainage and high shear strength. The pullout test results demonstrate that the interaction coefficient of polymeric strips and geogrid in IBA (0.73-1.53 and 0.79-1.91, respectively) is comparable or higher to materials conventionally used as structural fill in RSS, indicating adequate bondage between IBA and geosynthetic reinforcement. Further, it is estimated that using IBA as a substitute for available river sand in the vicinity can potentially reduce the overall RSS project cost by 15-20%, even if IBA has to be transported 50 km away from the project site.
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Affiliation(s)
- Deepesh Bansal
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India.
| | - G V Ramana
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India.
| | - Manoj Datta
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India.
| | - Garima Gupta
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India.
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Przybilla P, Subkov E, Latorre SH, Zankovic S, Mayr HO, Killinger A, Schmal H, Seidenstuecker M. Effect of 20 μm thin ceramic coatings of hydroxyapatite, bioglass, GB14 and Beta-Tricalciumphosphate with copper on the biomechanical stability of femoral implants. J Mech Behav Biomed Mater 2023; 144:105951. [PMID: 37295386 DOI: 10.1016/j.jmbbm.2023.105951] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/31/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023]
Abstract
In the present work, we test four thin coatings for titanium implants, namely, bioglass, GB14, Beta-Tricalciumphosphate (β-TCP) and hydroxyapatite (HA) with and without incorporated copper ions for their osteointegrative capacity. A rabbit drill hole model for time intervals up to 24 weeks was used in this study. Implant fixation was evaluated by measuring shear strength of the implant/bone interface. Quantitative histological analysis was performed for the measurements of bone contact area. Implants with and without copper ions were compared after 24 weeks. Thin coatings of GB14, HA or TCP on titanium implants demonstrated high shear strength during the entire test period of up to 24 weeks. Results confirmed osteointegrative properties of the coatings and did not reveal any negative effect of copper ions on osteointegration. The integration of copper in degradable osteoconductive coatings with a thickness of approx. 20 μm represents a promising method of achieving antibacterial shielding during the entire period of bone healing while at the same time improving osteointegration of the implants.
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Affiliation(s)
- Philip Przybilla
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany; Department of Orthopaedics and Traumatology, University Hospital of Basel, Spitalstrasse 21, 4031, Basel, Switzerland
| | - Eugen Subkov
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Sergio H Latorre
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Sergej Zankovic
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Hermann O Mayr
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Andreas Killinger
- Institute for Manufacturing Technologies of Ceramic Components and Composites (IMTCCC), Faculty 07, University of Stuttgart, Allmandring 7b, 70569, Stuttgart, Germany
| | - Hagen Schmal
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany
| | - Michael Seidenstuecker
- G.E.R.N. Center of Tissue Replacement, Regeneration & Neogenesis, Department of Orthopedics and Trauma Surgery, Medical Center-Albert-Ludwigs-University of Freiburg, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Hugstetter Straße 55, 79106, Freiburg, Germany.
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15
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Plevachuk Y, Švec P, Švec P, Orovcik L, Bajana O, Yakymovych A, Rud A. Metal deposited nanoparticles as "bridge materials" for lead-free solder nanocomposites. Appl Nanosci 2023; 13:7387-7397. [PMID: 38099240 PMCID: PMC10716065 DOI: 10.1007/s13204-023-02898-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 06/03/2023] [Indexed: 12/17/2023]
Abstract
An influence of carbon nanotubes and carbon nanospheres coated by Au-Pd and Pt on the microstructure of solder/copper joints at room temperature and after aging at sub-zero temperature. The carbon nanosized admixtures were mixed with ternary Sn3.0Ag0.5Cu matrix to prepare a composite solder. The microstructure of the solder joints between the nanocomposite solders and a copper substrate was studied by scanning electron microscopy. It was found that minor (0.05 wt. %) admixtures of both the carbon nanospheres and nanotubes increase the shear strength of the solder joints and reduce the growth rate of the intermetallic Cu6Sn5 layer, formed at the interface between solder and copper. This effect may be related to the adsorption of nanoinclusions on the grain surface during the solidification process. Comparative analysis suggests that exposure for 2 months at 253 K does not lead to deterioration of such an important mechanical characteristic of the solder joint as shear strength, indicating the possibility of using these nanocomposite solders in microelectronic equipment even at temperatures below 0 ℃.
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Affiliation(s)
- Yuriy Plevachuk
- Department of Metal Physics, Ivan Franko National University of Lviv, Kyrylo and Mefodiy Str. 8, Lviv, 79005 Ukraine
- Institute of Physics, Slovak Academy of Sciences, Dubravska Cesta 9, 84511 Bratislava, Slovakia
| | - Peter Švec
- Institute of Physics, Slovak Academy of Sciences, Dubravska Cesta 9, 84511 Bratislava, Slovakia
| | - Peter Švec
- Institute of Physics, Slovak Academy of Sciences, Dubravska Cesta 9, 84511 Bratislava, Slovakia
- Centre of Excellence for Advanced Materials Application, Slovak Academy of Sciences, Dubravska Cesta 9, 84511 Bratislava, Slovakia
| | - Lubomir Orovcik
- Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Dubravska Cesta 9, 84513 Bratislava, Slovakia
| | - Otto Bajana
- Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Dubravska Cesta 9, 84513 Bratislava, Slovakia
| | - Andriy Yakymovych
- Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9/164, 1060 Vienna, Austria
| | - Alexander Rud
- G.V. Kurdyumov Institute for Metal Physics of NAS of Ukraine, Academician Vernadsky Boulevard36, Kyiv, 03142 Ukraine
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Agrawal I, Katge F, Patil D, Pradhan D, Nisar P. Comparative evaluation of shear bond strength of three different glass ionomer cement (conventional, zirconium-reinforced and advanced glass hybrid) in primary molars: an in vitro study. Eur Arch Paediatr Dent 2023:10.1007/s40368-023-00817-y. [PMID: 37341921 DOI: 10.1007/s40368-023-00817-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 06/14/2023] [Indexed: 06/22/2023]
Abstract
PURPOSE The success of restorative materials is largely dependent on their capacity to adhere to the tooth structure and withstand the various forces present in the oral cavity. So, the aim of present study was to evaluate and compare the shear bond strength (SBS) of Type IX Glass Ionomer Cement (GIC), Zirconomer, and Gold Label Hybrid GIC in primary molars. METHODS Thirty primary molars were selected based on inclusion and exclusion criteria. The molars were polished to provide a flat dentin surface after being inserted in auto polymerizing acrylic resin. The samples were randomly divided into three groups, equally and were bonded to GIC. On the dentin surface, restoration cylinders were made using a plastic mould that had an internal diameter and height of 5 mm and 3 mm, respectively. The cement was manipulated according to the manufacturer's directions through the plastic mould. Then, the samples were stored at room temperature for 10 days to mimic oral conditions. The Universal Testing Machine was used to test SBS. One-way ANOVA and the post hoc Tukey test were used to statistically assess the collected data. RESULTS A statistically significant difference was found in all three groups (p < 0.01), with Zirconomer demonstrating highest SBS, followed by Type IX GIC and Gold Label Hybrid GIC. CONCLUSION The SBS value of Zirconomer was better when compared to Type IX GIC and Gold Label Hybrid GIC.
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Affiliation(s)
- I Agrawal
- Department of Pediatric and Preventive Dentistry, Terna Dental College, Navi-Mumbai, Maharashtra, India
| | - F Katge
- Department of Pediatric and Preventive Dentistry, Terna Dental College, Navi-Mumbai, Maharashtra, India.
| | - D Patil
- Department of Pediatric and Preventive Dentistry, Terna Dental College, Navi-Mumbai, Maharashtra, India
| | - D Pradhan
- Department of Pediatric and Preventive Dentistry, Terna Dental College, Navi-Mumbai, Maharashtra, India
| | - P Nisar
- Department of Pediatric and Preventive Dentistry, Terna Dental College, Navi-Mumbai, Maharashtra, India
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Youssef MK, Abdelkader SH, Aly YM. Effect of different interfacial surface treatments on the shear bond strength of veneering ceramic and zirconia core. BMC Oral Health 2023; 23:363. [PMID: 37277822 DOI: 10.1186/s12903-023-03057-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/17/2023] [Indexed: 06/07/2023] Open
Abstract
BACKGROUND Several interfacial surface treatments of zirconia surfaces have been proposed to improve adhesion to ceramic veneering. However, information regarding the durability and effect of such treatments on the bond strength following such treatments is lacking. AIM OF THE STUDY This study aimed to evaluate the shear bond strength between veneering ceramic and zirconia core after different interfacial surface treatments. MATERIALS AND METHODS Fifty-two discs (8 mm in diameter and 3 mm in height) were fabricated from zirconia blanks using a microtome cutting machine. Zirconia discs were divided into four groups (n = 13). Group I was subjected to air-borne abrasion using (Al2O3), group II was coated by bioglass, group III was coated with ZirLiner, and group IV was subjected to wash firing (sprinkle technique). A cylinder (4 mm in diameter and 3 mm in height) of veneering ceramic was fired on top of the zirconia core. Shear bond strength (SBS) between zirconia core and veneering ceramic was evaluated by using a universal testing machine. The data was collected and statistically analysed using One-Way ANOVA followed by multiple pairwise comparisons using Bonferroni adjusted significance level. The failure modes were assessed using a stereomicroscope for each group. RESULTS The highest mean bond strength was recorded in group III (17.98 ± 2.51 MPa), followed by group II (15.10 ± 4.53 MPa), then group I 14.65 ± 2.97 MPa. The lowest mean bond strength was recorded in group IV (13.28 ± 3.55 MPa). CONCLUSIONS Surface treatments had an effect on the zirconia-veneer shear bond strength. Liner coating revealed the highest shear bond strength values, significantly higher in comparison to wash firing (sprinkle technique) .
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Affiliation(s)
- Marwa K Youssef
- Division of Fixed Prosthodontics, Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
| | - Sanaa H Abdelkader
- Division of Fixed Prosthodontics, Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| | - Yasser M Aly
- Division of Fixed Prosthodontics, Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
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18
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Li Y, Wei M, Wei W, Zhang W, Liu L. Feasibility of soil oxidation-reduction potential in judging shear behaviour of hydrocarbon-contaminated soil. J Environ Manage 2023; 342:118303. [PMID: 37276617 DOI: 10.1016/j.jenvman.2023.118303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/18/2023] [Accepted: 05/28/2023] [Indexed: 06/07/2023]
Abstract
This study investigates the indicative role of oxidation-reduction potential (ORP) and pH of hydrocarbon-contaminated soils on their shear characteristics, contributing to safer and more efficient ex-situ remediation and management processes. The presence of hydrocarbons alters the soil's shear strength by affecting the hydration shell thickness, fluid's dielectric properties, and ion/electron exchange, as well as the soil's electrochemical force, which in turn affects the ORP and pH. The relationship between hydrocarbon concentrations in contaminated soils (0.1-15%) and corresponding ORP/pH values could be fitted linearly with a good correlation coefficient r (0.978), highlighting the potential of ORP/pH as an indicator for pollutant occurrence. Furthermore, the relationships between ORP/pH and shear strength, as tested in our study and obtained after processing from relevant literature sources, exhibited a strong fit (r = 0.976-0.995). The Mohr-Coulomb criterion modified using the ORP/pH parameter was established, which could improve the fitting effect of these relationships (r = 0.988-0.996), verifying the reliability of the novel criterion and application feasibility of ORP/pH. In future research, this modified criterion can be employed to conveniently assess the shear strength of contaminated soil by considering the shear behaviour of virgin soil and the ORP/pH values of the contaminated soil.
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Affiliation(s)
- Yuan Li
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China; IRSM-CAS/HK Poly U Joint Laboratory on Solid Waste Science, Wuhan, 430071, China; Hubei Province Key Laboratory of Contaminated Sludge and Soil Science and Engineering, Wuhan, 430071, China
| | - Mingli Wei
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China; Jiangsu Institute of Zoneco Co., Ltd., Yixing, 214200, China.
| | - Wei Wei
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenwei Zhang
- Wuhan Domestic Waste Classification Promotion Center, Wuhan, 430015, China
| | - Lei Liu
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China; IRSM-CAS/HK Poly U Joint Laboratory on Solid Waste Science, Wuhan, 430071, China; Hubei Province Key Laboratory of Contaminated Sludge and Soil Science and Engineering, Wuhan, 430071, China.
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Falamaki A, Salimi M, Vakili AH, Homaee M, Aryanpour M, Sabokbari M, Dehghani R, Masihzadeh K, Karimi AH. Experimental investigation of the effect of landfill leachate on the mechanical and cracking behavior of polypropylene fiber-reinforced compacted clay liner. Environ Sci Pollut Res Int 2023:10.1007/s11356-023-27512-1. [PMID: 37256403 DOI: 10.1007/s11356-023-27512-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 05/04/2023] [Indexed: 06/01/2023]
Abstract
This paper aims to investigate the effect of leachate on the geotechnical parameters and the cracking behavior of compacted clay liners (CCLs) containing different percentages of polypropylene fibers. Accordingly, 200 compacted clay samples were reinforced with different percentages of fiber contents (FC) (i.e., 0, 0.5, 0.75, and 1%) and prepared with water or leachate to conduct different laboratory tests. First, the physical properties of the clay were determined. Then, the shear strength parameters (i.e., cohesion and friction angle), unconfined compressive strength, and the hydraulic permeability were determined subjected to water or leachate. Notably, the cracking behavior was modeled using visual images of the samples. The leachate increased desiccation cracks in the natural soil from 0.425 to nearly 1.111%. However, the addition of 0.5% (in the case of water) and 1% (in the case of leachate) fiber to the soil reduced the surface desiccation cracks in clay liners to about 0.185 and 0.352%, respectively. In both water- or leachate-prepared samples, the addition of fibers significantly increased the cohesion and friction angle. The shear strengths of the unreinforced leachate-prepared samples were lower than those of the water-prepared samples. The shear strength and unconfined compressive strength of all specimens increased with increasing fiber percentage. The presence of fibers in all samples caused more ductile behavior. The required amount of energy to achieve the maximum strength in the samples increased with increasing FC. By increasing the percentage of fibers, the permeability of the natural soil and the leachate-prepared samples increased. However, the highest permeability was observed in the leachate-prepared samples containing 1% fibers of 8.3 × 10-10 m/s, which is less than 10-9 m/s (maximum allowable permeability for clay liners). Finally, the obtained results were satisfactorily confirmed by scanning electron microscopy (SEM) analysis.
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Affiliation(s)
- Amin Falamaki
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
| | - Mahdi Salimi
- Faculty of Engineering, Hamedan Branch, Islamic Azad University, Hamedan, Iran
| | - Amir Hossein Vakili
- Department of Civil Engineering, Faculty of Engineering, Zand Institute of Higher Education, Shiraz, Iran.
- Department of Environmental Engineering, Faculty of Engineering, Karabük University, Karabük, 78050, Turkey.
| | - Mehdi Homaee
- Department of Mining and Environmental Engineering, Faculty of Engineering, Tarbiat Modares University, Tehran, 14115, Iran
- Agrohydrology Research Group (Grant No. IG-39713), Tarbiat Modares University, Tehran, 14115, Iran
| | - Marzieh Aryanpour
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
| | - Maryam Sabokbari
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
| | - Reza Dehghani
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
| | - Kourosh Masihzadeh
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
| | - Amir Hossein Karimi
- Department of Civil Engineering, Payame Noor University, P.O. Box 19395-3697, Tehran, Iran
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20
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Zhong F, Qi C, Zhou Z, Zhang Z. Static characteristics study of pile-soil interaction under vertical electroosmosis. Heliyon 2023; 9:e15209. [PMID: 37089363 PMCID: PMC10114243 DOI: 10.1016/j.heliyon.2023.e15209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 03/12/2023] [Accepted: 03/29/2023] [Indexed: 04/25/2023] Open
Abstract
To study the improvement of pile bearing capacity and soil shear strength under the condition of vertical electroosmosis, the mucky soft soil is taken as the test object, and the vertical electroosmosis model test is conducted from top to bottom and from bottom to top. The shear strength test is conducted on the soil around the pile before and after the electroosmosis by observing the water content, soil surface settlement, soil current, soil pressure at the bottom of the pile, and other parameters; The static load test is carried out on the pile after electroosmosis and compared with the control group to study the static characteristics of pile-soil interaction under vertical electroosmosis. It is found that the ultimate bearing capacity of the # 1 side pile and the # 3 central pile has been increased by 3.7 times and 4.5 times, respectively, after electroosmosis, and the ultimate bearing capacity of the # 3 central pile is higher than that of the # 1 side pile, with an increase of 7.7%-9.2%. The effect of forward electroosmosis is better. Compared with reverse electroosmosis, the ultimate bearing capacity of the # 1 side pile and the # 3 center pile is increased by 18.5% and 16.8%, respectively.
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Affiliation(s)
- Fangtao Zhong
- College of Civil Engineering and Geographic Environment, Ningbo University, China
| | - Changguang Qi
- College of Civil Engineering and Geographic Environment, Ningbo University, China
- Corresponding author. Ningbo University, No. 818, Fenghua Road, Jiangbei District, Ningbo City, Zhejiang Province, 315211, China.
| | - Zijian Zhou
- College of Civil Engineering and Geographic Environment, Ningbo University, China
| | - Zhichao Zhang
- Geological Engineering Survey of Fujian Province, China
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21
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Zaini MSI, Hasan M, Jusoh WNBW. Utilization of bottom ash waste as a granular column to enhance the lateral load capacity of soft kaolin clay soil. Environ Sci Pollut Res Int 2023:10.1007/s11356-023-25966-x. [PMID: 36826761 DOI: 10.1007/s11356-023-25966-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Implementation of industrial wastes such as bottom ash in ground improvement can be cost-effective and environment-friendly. Ground improvement is an effective method of mitigation to improve problematic soils including soft kaolin clay soils as the problematic soils always expose to the severe settlements, low shear strength, immoderate plasticity, greater compressibility, dispersivity, bulging, erodibility, and susceptibility to climatic variables. Several studies conducted on the granular column using the bottom ash column. However, only a few studies have reported findings coherent with the statistical analysis. In this study, the lateral load capacity of bottom ash column-kaolin clay has been conducted. Coherently, the reinforced kaolin clay samples were tested via particle size distribution, Atterberg limit test, relative density, compaction test, permeability test, unconfined compression test, and unconsolidated undrained triaxial test with the single and group of encapsulated bottom ash columns with the geotextile encasement and a prediction model was developed. The effect of a number of columns, column diameter, column height, area replacement ratio, height penetration ratio, height-diameter column ratio, volume replacement ratio, and confining pressures on the shear strength of the single and group of encapsulated bottom ash columns have been investigated. The findings showed the effectiveness of using the bottom ash columns at various number of column, column diameter, column height, area replacement ratio, height penetration ratio, height-diameter column ratio, volume replacement ratio, and confining pressures can enhance the shear strength of the soil up to 77.00% at the optimal utilization of single encapsulated bottom ash column of 10-mm diameter and 80-mm height. Therefore, the study proved that the utilization of bottom ash waste as a granular column can significantly enhance the lateral load capacity of soft kaolin clay soil.
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Affiliation(s)
- Muhammad Syamsul Imran Zaini
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang, Lebuh Persiaran Tun Khalil Yaakob, 26300, Kuantan, Pahang, Malaysia
| | - Muzamir Hasan
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang, Lebuh Persiaran Tun Khalil Yaakob, 26300, Kuantan, Pahang, Malaysia.
| | - Wan Nursyafiqah Binti Wan Jusoh
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang, Lebuh Persiaran Tun Khalil Yaakob, 26300, Kuantan, Pahang, Malaysia
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Xing Z, Zhu L, Wu Y, Wu D, Gao C, Meng L, Feng X, Cheng W, Wang Z, Yang Y, Tang X. Effect of nano-TiO 2 particle size on the bonding performance and film-forming properties of starch-based wood adhesives. Int J Biol Macromol 2023; 235:123697. [PMID: 36806780 DOI: 10.1016/j.ijbiomac.2023.123697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/07/2023] [Accepted: 02/11/2023] [Indexed: 02/19/2023]
Abstract
The effect of nano-TiO2 particle size on the properties of starch-based wood adhesives was studied in this work. Our findings indicate that a smaller size of nano-TiO2 particles corresponds with a larger specific surface area and more hydroxyl sites on the particle surface that interact with latex molecules, forming a more compact network structure. Therefore, the bonding performance and water resistance of the adhesive were enhanced. In addition, rheology results showed that the adhesive behaves as a pseudoplastic fluid. Small-angle X-ray scattering and energy dispersive spectroscopy confirmed the good compatibility and dispersion of nano-TiO2 in the adhesive films. Diffusing wave spectroscopy and scanning electron microscopy showed that smaller TiO2 particles were more favorable for the formation of smoother and denser films. These results are of great significance for improving the structure and properties of starch-based wood adhesives and preparing high-performance environmentally friendly biobased adhesives.
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Affiliation(s)
- Zheng Xing
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Lihan Zhu
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Yinliang Wu
- Jiangsu Sanshu Biotechnology Co., Ltd, No. 188 Jimei Road, Chongchuan District, Nantong 226006, China
| | - Di Wu
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Chengcheng Gao
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Linghan Meng
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Xiao Feng
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Weiwei Cheng
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Zhenjiong Wang
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China.
| | - Yuling Yang
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China
| | - Xiaozhi Tang
- College of Food Science & Engineering, Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing University of Finance and Economics, Nanjing 210023, China.
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Hafhouf I, Abbeche K. Impact of drying-wetting cycles on shear properties, suction, and collapse of sebkha soils. Heliyon 2023; 9:e13594. [PMID: 36825165 PMCID: PMC9942005 DOI: 10.1016/j.heliyon.2023.e13594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 01/25/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Sebkha soils are known as saline formations that was rencontred generally in arid and semi-arid regions. With the alternation of drying-wetting cycles (D-W) these soils present variable morphological and geotechnical properties. These cycles D-W have an important effect on the mechanical behavior of sebkha soils which poses enormous problems for the construction of structures in general. In this study, compacted sebkha soil samples from Ain M'Lila, Algeria were subjected to three D-W cycles based on the natural drying process to reach the targeted water contents of 13, 11.4, 7 and 4%, in a laboratory environment. For each of these water contents, laboratory tests were conducted to study the effect of the D-W cycles on the collapse potential Cp, suction, and shear strength of the soil. The results obtained showed that the three components of suction, i.e., total, matric, and osmotic suctions decreased when the number of D-W cycles increased. Moreover, the collapse potential Cp increased with an increase in the number of D-W cycles. Moreover, the results obtained illustrated that the shear strength parameters were affected by the number of D-W cycles a significant decrease in cohesion and an increase in the internal friction angle were observed when the number of D-W cycles was increased. Finally, a correlation was found between the soil salinity and the three factors studied these were affected by the decrease in salinity under the effect of D-W cycles.
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Juarez MB, Mondelli G, Giacheti HL. An overview of in situ testing and geophysical methods to investigate municipal solid waste landfills. Environ Sci Pollut Res Int 2023; 30:24779-24789. [PMID: 36648718 PMCID: PMC9843669 DOI: 10.1007/s11356-023-25203-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Municipal solid waste (MSW) management is challenging as a whole. Global waste generation is expected to continue to increase in the coming years, and landfills are currently the primary destination. Therefore, the stability of these structures must be carefully evaluated to prevent failures and associated health and pollution risks, which implies the determination of waste properties using more reliable approaches. This paper presents a scoping review of field data from MSW landfills and outlines suggestions for future work. Studies published in the past twenty years were selected following a systematic search process in databases. Aspects discussed include (1) strength parameters and soil behavior type from in situ testing, (2) elastic moduli from seismic wave propagation, and (3) moisture content from geoelectrical measurements. Although the values of geotechnical parameters have varied due to waste heterogeneity and applied methods, the trends observed with depth and age could be compared. Research opportunities involve the spatial analysis of mechanical properties at a given site, seismic response of landfills with high organic content and saturation degree, interpretation of long-term resistivity monitoring, and combination of electrical properties to assess the degradation stages within the waste mass.
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Affiliation(s)
- Mariana Barbosa Juarez
- Department of Civil and Environmental Engineering, São Paulo State University (UNESP), Bauru, SP, Brazil.
| | - Giulliana Mondelli
- Department of Civil and Environmental Engineering, São Paulo State University (UNESP), Bauru, SP, Brazil
| | - Heraldo Luiz Giacheti
- Department of Civil and Environmental Engineering, São Paulo State University (UNESP), Bauru, SP, Brazil
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25
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Aladağ SÜ, Ayaz EA. Repair bond strength of different CAD-CAM ceramics after various surface treatments combined with laser irradiation. Lasers Med Sci 2023; 38:51. [PMID: 36689017 DOI: 10.1007/s10103-023-03715-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 01/16/2023] [Indexed: 01/24/2023]
Abstract
The aim of this study was to evaluate the effect of different surface treatments combined with laser irradiation on the shear bond strength of different CAD-CAM ceramics to composite resin. A total of hundred forty-seven ceramic specimens with thicknesses of 2.5 mm were prepared from three different CAD-CAM ceramics (an yttrium oxide partially stabilized tetragonal zirconia polycrystal (Y-TZP); a zirconia-reinforced lithium silicate glass ceramic (ZLS); and a lithium disilicate-strengthened lithium aluminosilicate glass ceramic (LD-LAS)) and subjected to seven groups of treatment (n = 7): (1) control (no treatment), (2) Er:YAG laser irradiation, (3) Nd:YAG laser irradiation, (4) etching with hydrofluoric acid (HFA), (5) Er:YAG + HFA, (6) Nd:YAG + HFA, and (7) sandblasting. After surface treatment procedures, a ceramic primer (Clearfil Ceramic Primer Plus, Kuraray, Japan) was applied to the ceramics. Bonding agent (Single Bond Universal Adhesive, 3 M ESPE, USA) was then applied, and the composite resin (Estelite Sigma Quick, Kuraray, Japan) was layered on the ceramic surfaces. The shear bond strength test was performed using a universal testing machine at a load of 0.5 mm/min. Data were analyzed by 2-way analysis of variance (ANOVA), and the Bonferroni correction was used for pairwise comparisons (α = 0.05). Compared to the bond strength of the control group, irradiation by Er:YAG and Nd:YAG lasers alone improved the bond strength of the composite resin to the Y-TZP (P < 0.001) but did not change the bond strength of composite resin to the ZLS and LD-LAS (P > 0.05). Compared to the bond strength of the control group, etching with HFA alone increased the bond strength of the composite resin to the ZLS and LD-LAS (P < 0.001) but did not affect the bond strength of the composite resin to the Y-TZP (P > 0.05). The highest bond strength of ZLS was obtained using HFA + Er:YAG, and the highest bond strength for LD-LAS was obtained using HFA + Nd:YAG. It was concluded that Er:YAG and Nd:YAG laser treatments presented the highest repair bond strength between the composite resin and Y-TZP ceramics. Er:YAG and Nd:YAG laser treatments in conjuction with HFA presented the highest repair bond strength between the composite resin and the glassy ceramics, ZLS, and LD + LAS.
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Affiliation(s)
- Seda Üstün Aladağ
- Department of Prosthodontics, Faculty of Dentistry, Bursa Uludağ University, Bursa, Turkey
| | - Elif Aydoğan Ayaz
- Department of Prosthodontics, Faculty of Dentistry, Karadeniz Technical University, Trabzon, Turkey.
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26
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You X, Chen L, Xu J, Li S, Zhang Z, Guo L. Effects of carbodiimide combined with ethanol-wet bonding pretreatment on dentin bonding properties: an in vitro study. PeerJ 2022; 10:e14238. [PMID: 36299505 PMCID: PMC9590415 DOI: 10.7717/peerj.14238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 09/23/2022] [Indexed: 01/24/2023] Open
Abstract
Purpose This study evaluated the combined effects of Carbodiimide (EDC) and ethanol-wet bonding (EWB) pretreatment on the bond strength and resin-dentin surface. Methods Phosphoric acid-etched dentin specimens were randomly divided into five groups based on the following pretreatments: deionized water (control), EWB, 0.3M EDC in water (EDCw), EDC water solution combined EWB (EDCw + EWB), and 0.3M EDC in ethanol (EDCe). A scanning electron microscope (SEM) was used to observe the morphology of collagen fibrils on the demineralized dentin matrix in each group after pretreatment. The adhesives Prime & Bond NT (PB) (Dentsply De trey, Konstanz, Germany) or Single bond 2 (SB) (3M ESPE, St. Paul, MN, USA) was applied after pretreatments, and a confocal laser scanning microscope (CLSM) was used to evaluate the quality of resin tags. The degree of conversion (DC) of the adhesive was investigated by Fourier transform infrared spectroscopy (ATR-FTIR). The dentin was first bonded with resin and bathed in water at 37 °C for 24 h. Half of them were subjected to 10, 000 cycles in a thermocycler between 5 °C and 55 °C before a microshear bond strength (µSBS) test. The statistical methods were Analysis of Variance (ANOVA) and a Tukey post hoc test at α = 0.05. Results The µSBS was significantly affected by pretreatments (p < 0.001), adhesives (p < 0.001), and aging conditions (p < 0.001) as revealed by the three-way ANOVA. The EDCw, EDCw + EWB, and EDCe groups significantly increased the µSBS; the EDCw + EWB and EDCe groups produced the highest µSBS. In the EDC-containing groups, the SEM showed at the collagen fibrils in the dentin matrix formed a three-dimensional network structure in the tubules after cross-linking into sheets, and the hybrid layer formed thicker resin tags under a CLSM. In the EDC-containing groups, the CLSM observed an increase in the length of resin tags. PB showed a higher DC and bonding strength than SB, and the five pretreatment groups tested did not affect the DC of the two adhesives. Conclusions In etch-and-rinse bonding system, EDC combined with EWB pretreatment can improve the quality of the hybrid layer and enhance the mechanical properties of demineralized dentin matrix. Pretreatment with EDC-ethanol solution may be a new clinically friendly option for enhancing dentin bonding durability.
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Affiliation(s)
- Xiaoxiao You
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
| | - Long Chen
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
| | - Jie Xu
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
| | - Sihui Li
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
| | - Zhenghao Zhang
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
| | - Ling Guo
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Southwest Medical University, Luzhou, China
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27
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Liu D, Liu D, Gao J, Yang Y, Ding Y, Guo C, Zhang X, Xia Z, Xu W. Influence of addition of two typical activated carbons on fertility properties and mechanical strength of vegetation concrete under freeze-thaw conditions. Sci Total Environ 2022; 838:156446. [PMID: 35660577 DOI: 10.1016/j.scitotenv.2022.156446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 05/14/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Under freeze-thaw conditions, the substrates used for ecological protection degrade, which involves decreases in compactness and fertiliser retention ability. As such, our purpose in this study was to use two typical types of activated carbon (AC), wood-based activated carbon (WAC) and coal-based activated carbon (CAC), to enhance the antifrost property of vegetation concrete (VC). We investigated the effects of five different proportions of planting soil weight (0.5 %, 1 %, 2 %, 4 %, and 6 %) mixed in each type of AC to determine their influence on the physical, mechanical, chemical, and biological properties of VC. The VC samples prepared without AC were used as control check (CK). The results showed that AC addition effectively enhanced the nutrient retention and microorganism capacity of VC under freeze-thaw conditions (10 and 60 freeze-thaw cycles). The leaching loss rate of ammonium nitrogen (NH4+-N) decreased to 31.98 % for WAC-6 %-60 from 46.87 % for CK-60, and the microorganism biomass carbon (MBC) increased to 138.54 mg·kg-1 for WAC-6 %-60 from 103.52 mg·kg-1 for CK-60. However, we observed some negative effects, including decreases in the cohesion and internal friction angle. In addition, the water holding capacity and matric suction first increased and then decreased as the proportion of AC mixed in the VC increased, with a turning point of approximately 2 %. By comprehensively considering previous VC eco-restoration technology study results, the recommended mixing amount of AC is 1 %-2 %, which would take full advantage of the benefits of AC and ensure that any negative effect of its use falls within an acceptable range. In addition, WAC generally performed better than CAC, but the aging rate of the former was faster than that of the latter according to scanning electron microscopy (SEM) images and dissolved organic carbon (DOC) analysis. From our results, we concluded that incorporating AC into VC improves the suitability of VC when applied in freeze-thaw conditions.
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Affiliation(s)
- Daxiang Liu
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China; Key Laboratory of Mountain Hazards and Surface Processes, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, PR China
| | - Deyu Liu
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China
| | - Jiazhen Gao
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China
| | - Yueshu Yang
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area (China Three Gorges University), Ministry of Education, Yichang 443002, PR China.
| | - Yu Ding
- Key Laboratory of Geological Hazards on Three Gorges Reservoir Area (China Three Gorges University), Ministry of Education, Yichang 443002, PR China
| | - Chaoqi Guo
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China
| | - Xiuzheng Zhang
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China
| | - Zhenyao Xia
- Key Laboratory of Disaster Prevention and Mitigation (China Three Gorges University), Hubei Province, Yichang 443002, PR China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area (China Three Gorges University), Ministry of Education, Yichang 443002, PR China
| | - Wennian Xu
- Key Laboratory of Geological Hazards on Three Gorges Reservoir Area (China Three Gorges University), Ministry of Education, Yichang 443002, PR China
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Goncu TB, Yilmaz NA. Universal adhesive application to contaminated/non-contaminated dentin with three different protocols: An in vitro shear bond strength and SEM analysis. Dent Mater J 2022; 41:633-642. [PMID: 35793969 DOI: 10.4012/dmj.2022-034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study aimed to comparatively evaluate the shear bond strength (SBS) of a universal adhesive to contaminated/non-contaminated dentin when applied with three different protocols. One-hundred-eighty dentin samples were divided randomly into 12 groups (n=15). The groups were created by combining four dentin contamination conditions (non-contaminated or contaminated with blood, hemostatic, or blood+hemostatic) with three application protocols for Single Bond Universal (no-preconditioning or preconditioning with the 35% phosphoric or 1% gallic acid). Following thermal cycling, the SBS test was performed. Data were analyzed using two-way-ANOVA and Tukey's HSD (p<0.05). Dentin surfaces subjected to phosphoric acid, gallic acid, or hemostatic were examined using scanning electron microscope (SEM) analysis. SBS results were influenced by both the dentin contamination (p<0.001) and application protocol (p<0.001). A significant interaction was found between the two factors (p=0.005). The highest bonding performance to contaminated dentin -at all contamination conditions- was achieved with the gallic acid preconditioning.
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Affiliation(s)
- Tuğçe Baloglu Goncu
- Department of Restorative Dentistry, Faculty of Dentistry, Aydin Adnan Menderes University
| | - Nasibe Aycan Yilmaz
- Department of Restorative Dentistry, Faculty of Dentistry, Aydin Adnan Menderes University
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29
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Ng CWW, Cai W, So PS, Liao J, Lau SY. Effects of biochar on shear strength of completely decomposed granite. Environ Sci Pollut Res Int 2022; 29:49422-49428. [PMID: 35554808 DOI: 10.1007/s11356-022-20707-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Biochar has a great potential to sustainably improve the performance of bio-engineered slope due to its ability to retain water and to supply nutrients. Existing studies mainly focus on hydrological properties of biochar-amended soil. However, the effects of biochar on shear strength of soil are not well studied. This study aims to assess the shearing behaviour of biochar-amended completely decomposed granite (CDG). Soil specimens were prepared by mixing CDG with two types of biochar at a mass ratio of 5% and compacted at 95% of the maximum dry density. Although the peak shear strength of biochar-amended CDG is reduced by up to 20% because of lower initial dry density of the soil and crushing of biochar particles during shearing, both types of biochar have negligible effects on the ultimate shear strength, which is governed by friction between soil particles. This highlights that the ultimate friction angle can be adopted for designing bio-engineered slopes using biochar-amended soils.
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Affiliation(s)
- Charles Wang Wai Ng
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Weiling Cai
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Pui San So
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jiaxin Liao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Sze Yu Lau
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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30
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Wang B, Zhang Z, Xu H, Huang M, Nie C, Li T. Effects of the reinforcement content and reinforcement scale on the shear strength characteristics of mechanically biologically treated waste. Environ Sci Pollut Res Int 2022; 29:53496-53508. [PMID: 35288856 DOI: 10.1007/s11356-022-19320-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
Mechanical and biological treatment (MBT), which can be used for waste reduction and for the burning of methane from biological treatments to generate electricity and heating, has become a popular research topic in environmental geotechnical engineering. This study investigated the mechanical behaviour of MBT waste and the effects of different reinforcement contents and reinforcement scales on its shear strength characteristics, and 68 groups of MBT waste samples from the Hangzhou Tianziling landfill were tested in the laboratory with a direct shear test apparatus. The samples exhibited displacement hardening behaviour in their mechanical response. The results show that the content and scale of the reinforced materials in MBT waste play an important role in the strength characteristics of MBT waste, and graphs showing the variation of the MBT waste shear strength and shear strength parameters with different reinforcement contents and reinforcement scales are shown. The range of cohesion c is 6.0-12.0 kPa, and the internal friction angle φ is 15.6-26.6°, respectively. The results of this study provide a reference for the assessment of slope stability at MBT landfills.
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Affiliation(s)
- Bang Wang
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Zhenying Zhang
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
| | - Hui Xu
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Menghe Huang
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Chengyu Nie
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Tuo Li
- School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, 310018, China
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31
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Strazzi-Sahyon HB, da Silva LMAV, Briso ALF, Dos Santos PH. In vitro study on how antioxidant solutions affect enamel surface characteristics and bonding interface of ceramic laminate veneers luting after dental bleaching. J Mech Behav Biomed Mater 2022; 133:105322. [PMID: 35724532 DOI: 10.1016/j.jmbbm.2022.105322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/06/2022] [Accepted: 06/13/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE This in vitro study aimed to determine the effect of antioxidant solutions used after dental bleaching on the shear bond strength and adhesive interface sealing of ceramic laminate veneer luting. Additionally, effects on the enamel surface characteristics of hydrogen peroxide neutralization, surface energy, total free interaction energy, morphology, and chemical composition of enamel were assessed. MATERIAL AND METHODS Total 127 bovine incisors were divided into experimental groups, according to the surface treatment (unbleached and bleached enamel), antioxidant types (control; 10% ascorbic acid and 10% α-tocopherol), and periods of luting of ceramic laminates (24 h and after 14 days). Shear bond strength was assessed using microtensile test before and after thermal cycling (5760 cycles, 5-55 °C) (n = 6). The sealing of the adhesive interface was assessed using a confocal laser scanning microscope (n = 3). Hydrogen peroxide neutralization analysis was performed using a spectrophotometer (n = 5). The surface energy and total free interaction energy (n = 10) were measured using an automatic goniometer, while enamel morphology and chemical composition were assessed by scanning eletron microscopy (n = 3). Shear bond strength and enamel surface properties data were subjected to ANOVA followed by Tukey's test (α = 0.05). Adhesive interface micrographs were evaluated by the inter-examiner Kappa test and subjected to Kruskal-Wallis and Dunn's tests (α = 0.05). RESULTS In general, thermal aging decreased the shear bond strength values of the luting agents to enamel (P < .05). The α-tocopherol solution was able to reverse the oxidizing effect from dental bleaching, increasing the shear bond strength values and preserving the integrity of the adhesive interface sealing (P < .05). Moreover, the α-tocopherol antioxidant agent promoted higher hydrogen peroxide neutralization after dental bleaching (P < .05). Dental bleaching influenced the enamel surface, decreasing the surface energy and total free interaction energy values (P < .05). CONCLUSION α-tocopherol was able to reverse the oxidizing effects of dental bleaching, improving the enamel surface properties, as well as the adhesion and interface sealing of ceramic laminate veneer restorations.
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Affiliation(s)
- Henrico Badaoui Strazzi-Sahyon
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University, UNESP, Araçatuba, SP, Brazil.
| | - Livia Maria Alves Valentim da Silva
- Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, São Paulo State University, UNESP, Araçatuba, SP, Brazil.
| | - André Luiz Fraga Briso
- Department of Preventive and Restorative Dentistry, Araçatuba School of Dentistry, Sao Paulo State University, UNESP, Araçatuba, SP, Brazil.
| | - Paulo Henrique Dos Santos
- Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, São Paulo State University, UNESP, Araçatuba, SP, Brazil.
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Fotovat F, Shishehian A, Alijani S, Alafchi B, Parchami P. Comparison of shear bond strength of orthodontic stainless-steel brackets on temporary crowns fabricated by three different methods: An in vitro study. Int Orthod 2022;:100641. [PMID: 35624022 DOI: 10.1016/j.ortho.2022.100641] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND AIMS Different methods are available for making temporary restorations. The purpose of this study was to determine and compare the shear bond strength of orthodontic brackets on temporary crowns made by three different methods. MATERIALS AND METHODS In this experimental study, disc form samples (N=54) were made in dimensions 8×1mm, according to the manufacturer's instructions. In this study, we had three groups (N=18) based on manufacturing methods (3D printing, conventional, and CAD/CAM). Following surface preparation of the samples, the brackets were bonded in the centre of the discs. Before the shear bond strength test, the samples were subjected to the thermocycling process. The shear bond strength of brackets was measured by Universal Testing Machine. Data were analysed by one-way ANOVA and LSD post hoc test. RESULTS The findings indicated that the mean shear bond strength of orthodontic stainless-steel brackets on temporary crowns varied between CAD/CAM and 3D printing methods (P<0.001) and also between CAD/CAM and conventional methods (P<0.001). The mean shear bond strength of orthodontic stainless steel brackets on temporary crowns was not different between 3D printing and conventional methods (P=0.7). CONCLUSION The shear bond strength of orthodontic stainless-steel brackets bonded to temporary crowns fabricated by conventional and 3D printing methods was similar, and the shear bond strength in the samples fabricated by CAD/CAM method was lower than other specimens.
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Ciliveri S, Bandyopadhyay A. Influence of strut-size and cell-size variations on porous Ti6Al4V structures for load-bearing implants. J Mech Behav Biomed Mater 2022; 126:105023. [PMID: 34999490 PMCID: PMC8792312 DOI: 10.1016/j.jmbbm.2021.105023] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/14/2021] [Accepted: 11/28/2021] [Indexed: 02/03/2023]
Abstract
Mechanical properties of porous metal coatings in load-bearing implants play a critical role in determining the in vivo lifetime. However, there is a knowledge gap in measuring the shear strength of porous metal coatings at the porous-dense interface. This study evaluated pore morphology dependence and strut-size on compression, shear deformation, and in vitro response of additively manufactured porous Ti6Al4V structures. Selective laser melting (SLM)-based additive manufacturing (AM) technique was used to process two types of structures with honeycomb cell design-one with constant cell-size of ∼470 μm with mean strut-size varying from 92 to 134 μm, and denoted as strut-size variation (SSV); and the other with a constant strut-size of ∼135 μm with mean cell-size varying from 580 to 740 μm, denoted as cell-size variation (CSV). It was observed that under compressive loading, changes in elastic modulus were more sensitive to variations in strut-size over cell-size. Under shear loading at the porous-dense interface, strength enhancement and material hardening were observed in both SSV and CSV samples due to pore-collapsing. Our results show that for hexagonal cell designs, shear behavior is more sensitive to variations in cell-size over strut-size, although elastic modulus is more sensitive to changes in strut-size for porous metallic structures. From in vitro hFOB analysis, it was observed that pore size of 670 μm demonstrated the highest osteoblast cell viability among porous structures with evidence of pore-bridging by cells. P. aeruginosa bacterial culture showed that bacterial cell viability was higher for porous structures than dense Ti, with evidence of pore-bridging by bacterial cells.
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Maleki-Kakelar M, Azarhoosh MJ, Golmohammadi Senji S, Aghaeinejad-Meybodi A. Urease production using corn steep liquor as a low-cost nutrient source by Sporosarcina pasteurii: biocementation and process optimization via artificial intelligence approaches. Environ Sci Pollut Res Int 2022; 29:13767-13781. [PMID: 34599437 DOI: 10.1007/s11356-021-16568-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 09/12/2021] [Indexed: 06/13/2023]
Abstract
To commercialize the biocementation through microbial induced carbonate precipitation (MICP), the current study aimed at replacing the costly standard nutrient medium with corn steep liquor (CSL), an inexpensive bio-industrial by-product, on the production of urease enzyme by Sporosarcina pasteurii (PTC 1845). Multiple linear regression (MLR) in linear and quadratic forms, adaptive neuro-fuzzy inference system (ANFIS), and genetic programming (GP) were used for modeling of process based on the experimental data for improving the urease activity (UA). In these models, CSL concentration, urea concentration, nickel supplementation, and incubation time as independent variables and UA as target function were considered. The results of modeling showed that the GP model had the best performance to predict the extent of urease, compared to other ones. The GP model had higher R2 as well as lower RSME in comparison with the models derived from ANFIS and MLR. Under the optimum conditions optimized by GP method, the maximum UA value of 3.6 Mm min-1 was also obtained for 5%v/v CSL concentration, 4.5 g L-1 urea concentration, 0 μM nickel supplementation, and 60 h incubation time. A good agreement between the outputs of GP model for the optimal UA and experimental result was obtained. Finally, a series of laboratory experiments were undertaken to evaluate the influence of biological cementation on the strengthening behavior of treated soil. The maximum shear stress improvement between bio-treated and untreated samples was 292% under normal stress of 55.5 kN as a result of an increase in interparticle cohesion parameters.
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Ray S, Mishra AK, Kalamdhad AS. Hydraulic performance, consolidation characteristics and shear strength analysis of bentonites in the presence of fly-ash, sewage sludge and paper-mill leachates for landfill application. J Environ Manage 2022; 302:113977. [PMID: 34688046 DOI: 10.1016/j.jenvman.2021.113977] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/12/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
A rapid upsurge in urban and industrial developments leads to increased generations of solid wastes. The most accepted technique of waste discarding around the world is landfilling. Leaching chemicals from municipal dumping grounds can pollute the groundwater source and the surrounding environment without appropriate precautionary measures. Bentonite is a low-cost constituent used as a liner material in landfills due to its low permeability, high sealing ability, high specific surface area, and the ability to hold up the impurity migration through adsorption. However, leachate interaction with bentonite may alter its properties and reduce its usefulness as a barrier material in the long term. Also, bentonite having different chemical and mineralogical compositions will behave differently due to the leachate interaction. Therefore, it is necessary to compare the performance of various bentonites in the presence of leachates. In the present investigation, two Indian bentonites of different mineralogical compositions were studied for their change in the index properties, swelling, swelling potential, swelling pressure, hydraulic conductivity, consolidation parameters and shear strength properties in the presence of fly ash, sewage sludge and paper mill leachates. The outcomes showed that in the presence of all the leachates, liquid limit, free swell, compression index, swelling potential, swelling pressure, time to complete 90% of consolidation and shear strength dropped; whereas, hydraulic conductivity and coefficient of consolidation increased. Besides, the quality of bentonite prominently influenced the hydraulic, strength and swelling behaviour. The bentonite having a higher cation exchange capacity, liquid limit, specific surface area, and swelling capability undergoes a higher variability in the free swell (80.0, 73.8 and 76.9% decline), liquid limit (73.5, 61.7 and 69.2% decline), swelling potential (61.3, 55.7 and 51.0% decline), swelling pressure (53.3 and 56.4% decrease), and hydraulic conductivity (57.5, 8.6 and 41.1 times increase at a void ratio of 1.2) values when infused with fly ash, sewage sludge and paper mill leachates, respectively. The study also showed that the fly ash leachate interaction causes a higher variation in bentonite behaviour than sewage sludge and paper mill leachates. The study's findings would prove beneficial to design engineers for selecting bentonite types for landfill liners.
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Affiliation(s)
- Saswati Ray
- Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| | - Anil Kumar Mishra
- Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| | - Ajay S Kalamdhad
- Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
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Duarte Santos Lopes L, da Silva Pedrosa M, Beatriz Melo Oliveira L, Maria da Silva Costa S, Aguiar Santos Nogueira Lima L, Lucisano Botelho do Amaral F. Push-out bond strength and failure mode of single adjustable and customized glass fiber posts. Saudi Dent J 2021; 33:917-922. [PMID: 34916764 PMCID: PMC8665234 DOI: 10.1016/j.sdentj.2021.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 05/14/2021] [Accepted: 09/06/2021] [Indexed: 11/28/2022] Open
Abstract
Purpose To evaluate the push-out bond strength (PBS) and failure mode of single adjustable (SAP) and customized (CP) posts cemented to root canal dentin using conventional (RelyX Ultimate) or self-adhesive (RelyX U200) dual-cure resin cements. Methods Herein, 40 bovine mandibular incisors were divided into four groups (n = 10): SAP cemented with RelyX Ultimate (SAP-UT), SAP cemented with RelyX U200 (SAP-U2), CP cemented with RelyX Ultimate (CP-UT), and CP cemented with RelyX U200 (CP-U2). PBS and failure modes were analyzed. Three-way repeated measures ANOVA test followed by Tukey’s test and Fisher–Freeman–Halton exact test were used for data analysis (α = 5%). Results The PBS values for SAP (p < .05) were higher than those for CP and were not influenced by the root third and resin cement (p > .05). When conventional resin cement was used, the SAP showed significant differences compared to CP (p < .05). When cemented with RelyX Ultimate, a higher prevalence of mixed and adhesive failures for SAP and CP, respectively, was observed (p < .05). For the self-adhesive resin cement, the failures were mostly adhesive (p < .05). Conclusion SAP showed better performance than CP. The root third and resin cements did not influence the PBS. The most prevalent failures were adhesive and mixed.
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Affiliation(s)
- Lívia Duarte Santos Lopes
- São Leopoldo Mandic Institute and Research Center, Campinas, São Paulo, Brazil.,Course of Dentistry, Centro Universitário UniFacid
- Wyden, Teresina, Piauí, Brazil
| | - Marlus da Silva Pedrosa
- Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo, São Paulo, Brazil
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de Araújo Neto CL, Gurjão RÍL, Farias AP, de Melo MC, Monteiro VED. Physical, chemical, and mechanical properties of landfilled waste from Campina Grande, Brazil. Environ Sci Pollut Res Int 2021; 28:66819-66829. [PMID: 34236611 DOI: 10.1007/s11356-021-15230-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
The properties of municipal solid waste (MSW) in landfills vary considerably, depending on the waste's composition, time, and density. This variability in MSW properties leads to many uncertainties in the analysis of landfill performance. Therefore, this study aimed to evaluate landfilled waste's physical, chemical, and mechanical properties for 8 days. Throughout this study, it was possible to investigate the gravimetric composition, density of solid particles, moisture content, volatile solids, pH, total alkalinity, chemical oxygen demand (COD), ammoniacal nitrogen (N-NH3), grain size distribution, compaction properties, and shear strength of the landfilled waste. It was found that 71% of the waste corresponds to the denominated "others" category, the content of fine materials is 65%, the optimum water content is 34%, the moisture content is 41%, and the volatile solids is 67%. The chemical parameters indicated that the MSW was in the initial phase of biodegradation (acidogenesis), as the pH, total alkalinity, COD, and N-NH3 showed to be 5, 1575 mgCaCO3.L-1, 13698.6 mgO2.L-1, and 56 mgN-NH3.L-1, respectively. On the mechanical aspect, the waste presented a cohesion of 17 kPa and an internal friction angle of 16°. In general, the results showed that the waste's physical, chemical, and mechanical properties altered during the landfilling process.
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Affiliation(s)
- Cláudio Luis de Araújo Neto
- Federal University of Campina Grande, Aprígio Veloso St., 882, Universitário, Campina Grande, PB, 58428-830, Brazil
| | - Renan Ítalo Leite Gurjão
- Federal University of Campina Grande, Aprígio Veloso St., 882, Universitário, Campina Grande, PB, 58428-830, Brazil.
| | - Amanda Paiva Farias
- Federal University of Campina Grande, Aprígio Veloso St., 882, Universitário, Campina Grande, PB, 58428-830, Brazil
| | - Márcio Camargo de Melo
- Federal University of Campina Grande, Aprígio Veloso St., 882, Universitário, Campina Grande, PB, 58428-830, Brazil
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da Silva CMF, de Menezes Costa AF, Costa AR, Neves JG, de Godói APT, de Góes VFF. Influence of different acid etching times on the shear bond strength of brackets bonded to bovine enamel. Saudi Dent J 2021; 33:474-480. [PMID: 34803289 PMCID: PMC8589615 DOI: 10.1016/j.sdentj.2020.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 09/14/2020] [Accepted: 10/15/2020] [Indexed: 10/28/2022] Open
Abstract
Introduction The most used product for surface acid conditioning for enamel is 37-40% phosphoric acid, which promotes greater mechanical retention. Aim The objective of this study was to compare the shear bond strength (SBS) of brackets bonded to bovine enamel with different acid conditioning protocols and to analyze the surface morphology. Materials and methods 169 teeth (n = 13) were divided into 4 groups: control group without conditioning (G1), Dental Gel 37% phosphoric acid (Dentsply) (G2), Ultra Etch 35% (Ultradent) (G3) and Attaque gel 37% (Biodinâmica) (G4). Groups G2, G3 and G4 were subdivided according to the conditioning time into: 10 s (a), 15 s (b), 30 s (c) and 60 s (d). The superficial enamel morphology (n = 3) was analyzed using a scanning electron microscopy (SEM) to analyze the depth of the microporosities. The samples were submitted to the shear test (SBS) with the aid of a universal testing machine (INSTRON) with a speed of 1 mm/min. The enamel after debonding was analyzed to determine the adhesive remnant index (ARI) in a stereoscopic magnifying glass. Statistical analysis used The SBS data were analyzed using two-way ANOVA. ARI data were analyzed using generalized linear models and SEM measurements were analyzed using Kruskal Wallis and Dunn tests. The 95% significance level was used. Results The SBS within G2, G3 and G4 ranged from 11.11 to 12.66 MPa. ARI score 3 was observed in 35% of the samples. The samples analyzed in the SEM showed microporosity depth rangingfrom 1.28 to 2.48 μm. Conclusions There was no difference between the acids and times evaluated for SBS. The ARI analysis showed that the studied acids provide protection to the enamel surface, keeping the adhesive attached to the buccal surface after debonding. The increase in conditioning time is directly proportional to the deterioration of the prismatic and interprismatic content.
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Affiliation(s)
- Clyvis Maurício Ferreira da Silva
- Graduated Student in Orthodontics, University Center of the Hermínio Ormetto Foundation (FHO), Araras, Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, CEP: 13607-339 SP, Brazil
| | - André Felipe de Menezes Costa
- Graduated Student in Orthodontics, University Center of the Hermínio Ormetto Foundation (FHO), Araras, Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, CEP: 13607-339 SP, Brazil
| | - Ana Rosa Costa
- University Center of the Hermínio Ometto Foundation (FHO), Araras, Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, SP, Brazil
| | - José Guilherme Neves
- Department of Dental Materials, School of Dentistry of Piracicaba, UNICAMP. Av. Limeira, 901 - Areião, Piracicaba, SP 13414-903, Brazil
| | - Ana Paula Terrosi de Godói
- University Center of the Hermínio Ometto Foundation (FHO), Araras, Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, SP, Brazil
| | - Vívian Fernandes Furletti de Góes
- University Center of the Hermínio Ometto Foundation (FHO), Araras, Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, SP, Brazil.,Fundação Hermínio Ometto (UNIARARAS), Avenida Dr. Maximiliano Baruto, 500 - Jd. Universitário, CEP: 13607-339, Brazil
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Mirhashemi A, Ahmad Akhondi MS, Sodagar A, Jalali YF, Jazi L. Effect of nano-zinc oxide and nano-chitosan particles on the shear bond strength of dental composites used as orthodontic adhesive. J World Fed Orthod 2021; 10:172-176. [PMID: 34483088 DOI: 10.1016/j.ejwf.2021.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/06/2021] [Accepted: 08/06/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND This study aimed to evaluate the effect of the combination of zinc oxide nanoparticles (NPs) and chitosan NPs on the shear bond strength (SBS) of composites used for orthodontic bonding. METHODS Four groups of composites (n = 10), containing 0%, 1%, 5%, and 10% w/w NP fillers, respectively, were used to bond brackets to the surfaces of 40 intact bovine incisors. After 1000 rounds of thermal cycling at 5°C-55°C, all specimens were mounted in acrylic blocks. The SBS was tested using a universal testing machine, and the adhesive remnant index scores were registered using a stereomicroscope. Data were statistically analyzed using a 1-way ANOVA and the Kruskal-Wallis test. RESULTS The highest value of mean SBS was found in the control group, and the lowest value was found in the group with composite containing 10% NPs. The adhesive remnant index did not differ significantly among the groups (P = 0.823). CONCLUSIONS Incorporation of 1% and 5% zinc oxide and chitosan NPs had no effect on the SBS of composite, and the obtained SBS values were similar to that of the control group.
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Affiliation(s)
- Amirhossein Mirhashemi
- Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Ahmad Sodagar
- Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Leila Jazi
- Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
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Li K, Zhao X, Xiao D. Acid rain: an unsuspected factor predisposing Panzhihua airport landslide, China. Environ Sci Pollut Res Int 2021; 28:36753-36764. [PMID: 33710488 DOI: 10.1007/s11356-021-13308-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
Understanding the effect of acid rain to landslides is crucial for a better landslide risk assessment. This work aims to reveal the unsuspected but key role of acid rain in Panzhihua airport landslide, China. Firstly, we propose a hypothesis that acid rain may aggravate the slaking behavior of mudstone at weak interlayer and make it more fragmented, eventually further reducing its shear strength and predisposing the Panzhihua airport landslide. Subsequently, mudstone samples are subjected to slaking durability test, respectively, using water with a pH of 7 and two dilute hydrochloric acid solution with pH of 5 and 3. Slaking durability index (Idn) is adopted aiming to quantitatively evaluate the impact of acid rain on the slaking. Moreover, the mechanisms of acid rain affecting the slaking behavior of mudstone are revealed by (1) analyzing cation compositions changes in different pH slaking fluid and (2) observing micro-structure change of mudstone-chip before and after acid rain treatment. Finally, three works are conducted as evidences to prove that acid rain indeed plays a key role in the occurrence of Panzhihua airport landslide, including (1) analysis of the link between the slaking behavior of mudstone and its shear strength, (2) comparison of cations between spring water at the edge of the toe of landslide and acid rain, and (3) comparison of mineral contents of mudstone samples collected from different locations. These findings have implications for comprehensively analyzing the formation mechanism of landslide in acid rain area (such as Europe, North America, and China).
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Affiliation(s)
- Kunpeng Li
- Department of Geology Engineering, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 611756, People's Republic of China
| | - Xiaoyan Zhao
- Department of Geology Engineering, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 611756, People's Republic of China.
| | - Dian Xiao
- Department of Geology Engineering, Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, Sichuan, 611756, People's Republic of China
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Lu T, Wang W, Wei Z, Yang Y, Cao G. Experimental study on static and dynamic mechanical properties of phosphogypsum. Environ Sci Pollut Res Int 2021; 28:17468-17481. [PMID: 33394448 DOI: 10.1007/s11356-020-12148-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
Phosphogypsum (PG) is a solid waste product of the wet-process phosphoric acid industry that accumulates in large amounts on the ground, forming PG ponds. In recent years, the amount of PG produced and discharged into ponds has increased significantly with the increase in the market demand for phosphate fertilizers. To enrich the basic knowledge of PG properties and provide basic data for the stability analysis of PG dams, a series of laboratory geotechnical tests, including permeability tests, compressibility tests, triaxial shear tests, and dynamic triaxial tests, were conducted in this study. During the preparation of the test samples, solubility and high-temperature dehydration of PG were considered. The results indicated that PG exhibits medium compressibility and medium to weak permeability characteristics. The stress-strain curves of the triaxial shear tests were divided into three typical stages: initial deformation stage, strain hardening stage, and destruction stage. With increasing dry density and consolidation confining pressure, both the shear strength and deformation modulus significantly increased. The relationship between the deformation modulus and confining pressure gradually changed from linear to logarithmic with increasing density. The liquefaction resistance curves (CSR-NL curves) of PG were expressed by power functions. With increasing dry density, the curves shifted higher and became steeper. Compared with the Hardin-Drnevich model, the Davidenkov model was found to be more suitable for describing the relationship between the dynamic shear modulus ratio and damping ratio of PG and the dynamic shear strain. Furthermore, compared with those of tailings and natural soils, the engineering mechanical properties of PG were relatively poor, which may be related to its uniform particle distribution and neat particle stacking structure.
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Affiliation(s)
- Ting Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China
- School of Resources and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Wensong Wang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
- School of Resources and Safety Engineering, Chongqing University, Chongqing, 400044, China.
| | - Zuoan Wei
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China.
- School of Resources and Safety Engineering, Chongqing University, Chongqing, 400044, China.
| | - Yonghao Yang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China
- School of Civil Engineering, Chongqing Jiaotong University, Chongqing, 400074, China
| | - Guansen Cao
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China
- School of Resources and Safety Engineering, Chongqing University, Chongqing, 400044, China
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Ryu JY, Kim YH, Lee JS, Lee JW, Oh EJ, Kim HM, Lee SJ, Lee J, Lee SY, Huh S, Kim JY, Im S, Chung HY. Oscillatory shear stress promotes angiogenic effects in arteriovenous malformations endothelial cells. Mol Med 2021; 27:31. [PMID: 33789563 PMCID: PMC8011119 DOI: 10.1186/s10020-021-00291-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 03/16/2021] [Indexed: 01/04/2023] Open
Abstract
Background Vascular endothelial cells (ECs) are subject to continuous shear stress due to blood circulation. Mechanical stress due to high shear flow can also cause arteriovenous malformation (AVM) when ECs respond hyper-sensitively to shear flow. This study was conducted to test the hypothesis that angiogenesis could be promoted in response to mechanical stress via regulation of pro-angiogenic factors in AVM cells. Methods ECs were extracted from the tissue samples from six AVM patients and six normal patients. Shear stress at 7 dynes/cm2 were applied for 24 h. Before and after application of shear stress to each group, RT-PCR was performed to access the expression levels of angiopoietin2(AGP2), aquaporin1(AQP1) and TGFβR1. Immunofluorescences was also performed to evaluate the level of protein expressions. Results In both normal and AVM tissues, AGP2 and TGFβR1 under the shear stress showed increased expression in the ECs compared to the non-sheared samples. When AVMs and normal arterial vasculature were compared, the expression levels of both AGP2 and TGFβR1 in AVMs were higher when compared to normal arterial vasculature with or without shear stress. Immunofluorescence-based protein analysis also confirmed shear-induced AGP2 and TGFβR1 in both samples of normal and AVM patients. Conclusions AVMs exhibited higher sensitivity to shear stress by producing higher expressions of some marked genes and proteins that regulate the endothelial functions upon exposure to shear stress. While the physiological mechanism for AVMs remain elusive, our study shows the plausibility of physical stress imposed by the shearing flow can cause the occurrence of AVMs.
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Affiliation(s)
- Jeong Yeop Ryu
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Yun Hyun Kim
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Joon Seok Lee
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Jeong Woo Lee
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Eun Jung Oh
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea.,Cell & Matrix Research Institute, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Hyun Mi Kim
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea.,Cell & Matrix Research Institute, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea
| | - Seok-Jong Lee
- Department of Dermatology, School of Medicine, Kyungpook National University, Daegu, 41944, Korea
| | - Jongmin Lee
- Department of Radiology, School of Medicine, Kyungpook National University, Daegu, 41944, Korea
| | - Sang Yub Lee
- Department of Radiology, School of Medicine, Kyungpook National University, Daegu, 41944, Korea
| | - Seung Huh
- Department of Surgery, School of Medicine, Kyungpook National University, Daegu, 41944, Korea
| | - Ji Yoon Kim
- Department of Pediatrics, School of Medicine, Kyungpook National University, Daegu, 41944, Korea
| | - Saewon Im
- School of Business Administration, Kyungpook National University, Daegu, 41944, Korea
| | - Ho Yun Chung
- Department of Plastic and Reconstructive Surgery, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea. .,Cell & Matrix Research Institute, School of Medicine, Kyungpook National University, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, Korea.
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Zhang D, Wu X, Tang J, Wang P, Chen GZ, Yin X. Hemodynamics is associated with vessel wall remodeling in patients with middle cerebral artery stenosis. Eur Radiol 2021; 31:5234-5242. [PMID: 33439317 DOI: 10.1007/s00330-020-07607-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/26/2020] [Accepted: 12/04/2020] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To evaluate the relationship between hemodynamics and vessel wall remodeling patterns in middle cerebral artery (MCA) stenosis based on high-resolution magnetic resonance imaging and computational fluid dynamics (CFD). METHODS Forty consecutive patients with recent ischemic stroke or transient ischemic attack attributed to unilateral atherosclerotic MCA stenosis (50-99%) were prospectively recruited. All patients underwent a cross-sectional scan of the stenotic MCA vessel wall. The parameters of the vessel wall, the number of patients with acute infarction, translesional wall shear stress ratio (WSSR), wall shear stress in stenosis (WSSs), and translesional pressure ratio were obtained. The patients were divided into positive remodeling (PR) and negative remodeling (NR) groups. The differences in vessel wall parameters and hemodynamics were compared. Correlations between the parameters of the vessel wall and hemodynamics were calculated. RESULTS Of the 40 patients, 16 had PR, 19 had NR, and the other 5 displayed non-remodeling. The PR group had a smaller lumen area (p = 0.004), larger plaque area (p < 0.001), normal wall index (p = 0.004), and higher WSSR (p = 0.004) and WSSs (p = 0.023) at the most narrowed site. The PR group had more enhanced plaques (12 vs 6, p = 0.03). The number of patients with acute stroke in the PR group was more than that in the NR group (11 vs 4, p = 0.01). The remodeling index (r = 0.376, p = 0.026) and plaque area (r = 0.407, p = 0.015) showed a positive correlation with WSSR, respectively. CONCLUSIONS Hemodynamics plays a role in atherosclerotic plaques and vessel wall remodeling. Individuals with greater hemodynamic values might be more prone to stroke. KEY POINTS • Stenotic plaques in middle cerebral artery with positive remodeling have smaller lumen area and larger resp. higher plaque area, normal wall index, translesional wall shear stress ratio, and wall shear stress than negative remodeling. • The remodeling index and plaque area are positively correlated with translesional wall shear stress ratio. • Hemodynamic may help to understand the role of positive remodeling in the development of acute stroke.
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Affiliation(s)
- Danfeng Zhang
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China
| | - Xinying Wu
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China
| | - Jie Tang
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China
| | - Peng Wang
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China
| | - Guo Zhong Chen
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China.
| | - Xindao Yin
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, Jiangsu, China.
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Mokhtarpur H, Nafisifard M, Dadgar S, Etemadi A, Chiniforush N, Sobouti F. Shear Bond Strength of the Metal Bracket to Zirconium Ceramic Restoration Treated by the Nd: YAG Laser and Other Methods: An In Vitro Microscopic Study. J Lasers Med Sci 2021; 11:411-416. [PMID: 33425291 DOI: 10.34172/jlms.2020.65] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: Providing reliable bonding of the bracket base and the zirconia surface is required to apply orthodontic force. The purpose of this scientific experiment was to evaluate the efficacy of three different methods of surface preparation for Zirconia, including surface roughening, sandblasting and the Nd: YAG laser, in the shear bond strength (SBS) of the orthodontic brackets. Methods: Fifty-four discs of zirconia were divided into three groups of 18: A) Hydrofluoric acid etching, B) sandblasting, and C) Nd: irradiation using the power of 1.5 W for 10 seconds. After bonding the brackets, the samples were slowly thermo-cycled (1000 times) for 24 hours. The SBS test was performed by a universal testing machine at a head speed of 0.5 mm/min. The adhesive remnant index (ARI) was scored at a magnification of 10 in the stereo microscope. All data were collected and analyzed using the variance, Kruskal-Wallis, Tukey, Don, and Weibull tests (α = 0.05). Results: The HF acid etching group (6.11± 0.94 MPa) had the highest SBS, which was followed by the laser group (6 ± 0.61 MPa) and the sandblast group (3.1080 ± 0.82 MPa). There was a significant statistical difference between the laser and HF groups and the sandblast group (P < 0.05) and no significant difference between the HF group and the laser group (P = 0.03). Conclusion: Based on the obtained bond strength, the Nd: YAG laser with a power of 1.5 W could be a substitute treatment method for the HF acid-etching.
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Affiliation(s)
- Hadi Mokhtarpur
- Prosthodontic Department, Dental Faculty, Mazandaran University of Medical Sciences, Sari, Iran
| | - Maliheh Nafisifard
- Restorative Dentistry Department, Dental Faculty, Babol University of Medical Sciences, Babol, Iran
| | - Sepideh Dadgar
- Orthodontic Department, Dental Faculty, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ardavan Etemadi
- Department of Periodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Nasim Chiniforush
- Dental Implant Research Center, Dental Research Institute, Tehran University of Medical Sciences, Tehran, Iran.,Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Italy
| | - Farhad Sobouti
- Orthodontic Department, Dental Faculty, Mazandaran University of Medical Sciences, Sari, Iran.,Dental Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran
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Kodaira A, Koizumi H, Hiraba H, Takehana K, Yoneyama T, Matsumura H. Adhesive bonding of noble metals with a thiohydantoin primer. Dent Mater 2020; 37:e176-e181. [PMID: 33341246 DOI: 10.1016/j.dental.2020.11.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/31/2020] [Accepted: 11/21/2020] [Indexed: 11/24/2022]
Abstract
OBJECTIVE The purpose of this study was to assess the effects of an experimental primer containing acetone solution and a sulfur-containing functional monomer, 10-methacryloyloxydecyl-(2-thiohydantoin-4-yl)propionate (MDTHP), on the bonds between noble metals and acrylic resin. METHODS The experimental primer used as the control for comparison consisted of 6-(4-vinylbenzyl-n-propyl)amino-1,3,5-triazine-2,4-dithione (VBATDT) in acetone. These primers were prepared as equimolar functional monomers (0.1 mol%). A self-polymerizing acrylic resin initiated with tri-n-butylborane (TBB) was used as the luting agent. Four elemental metal disks (silver, copper, palladium, and gold) were used as adherend specimens. All the disks were wet-ground with silicon carbide paper (#1500). Bonding reactions were performed on 12 combinations of the four metals, and the disks were either primed with MDTHP or VBATDT or were unprimed (control). Shear bond strengths were determined pre- and post-thermocycling (5-55 °C, dwell time 60 s, 20,000 cycles). The results were statistically analyzed via a non-parametric test (α = 0.05). RESULTS The post-thermocycling shear bond strengths of the MDTHP primer were as follows (median, n = 11): 13.2 MPa on silver, 25.9 MPa on copper, 4.1 MPa on palladium, and 11.3 MPa on gold. The MDTHP primer showed higher post-thermocycling shear bond strength on all the four metals. Additionally, on silver and copper, the MDTHP bond strengths were higher than on the other metals. SIGNIFICANCE Within the limitation of current of experimental setting, the MDTHP compound may be applicable as a functional monomer for bonding noble metal alloys.
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Affiliation(s)
- Akihisa Kodaira
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Division of Advanced Dental Treatment, Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Hiroyasu Koizumi
- Department of Dental Materials, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Division of Biomaterials Science, Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Haruto Hiraba
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Division of Advanced Dental Treatment, Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Kousuke Takehana
- Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Takayuki Yoneyama
- Department of Dental Materials, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Division of Biomaterials Science, Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Hideo Matsumura
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Division of Advanced Dental Treatment, Dental Research Center, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
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Farhadifard H, Rezaei-Soufi L, Farhadian M, Shokouhi P. Effect of different surface treatments on shear bond strength of ceramic brackets to old composite. Biomater Res 2020; 24:20. [PMID: 33292632 PMCID: PMC7687813 DOI: 10.1186/s40824-020-00199-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/10/2020] [Indexed: 11/10/2022] Open
Abstract
Background At present, the demand for orthodontic treatment is on the rise. On the other hand, evidence shows that the bond strength of composite resins to old composite restorations is often unreliable. Therefore, the aim of this in vitro study was to assess the effect of different surface treatments on shear bond strength (SBS) of ceramic brackets to old composite restorations. Methods In this in vitro experimental study, 60 nano-hybrid composite discs were fabricated. For aging, the discs were incubated in deionized water at 37 °C for 1 month. Next, they underwent 4 different surface treatments namely acid etching with 37% phosphoric acid, sandblasting, grinding, and Er,Cr:YSGG laser irradiation. Ceramic brackets were then bonded to the discs and underwent SBS testing. Results The maximum mean SBS value was obtained in the grinding group (9.16 ± 2.49 MPa), followed by the sandblasting (8.13 ± 2.58 MPa) and laser (6.57 ± 1.45 MPa) groups. The minimum mean SBS value was noted in the control group (5.07 ± 2.14 MPa). Conclusion All groups except for the control group showed clinically acceptable SBS. Therefore, grinding, sandblasting, and Er,Cr:YSGG laser are suggested as effective surface treatments for bonding of ceramic orthodontic brackets to aged composite.
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Affiliation(s)
- Homa Farhadifard
- Department of Orthodontics, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Loghman Rezaei-Soufi
- Department of Restorative Dentistry, School of Dentistry, Dental Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Maryam Farhadian
- Department of Biostatistics, School of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Parisa Shokouhi
- School of Dentistry, Hamadan University of Medical Sciences, 6517838677 Shahid Fahmideh Street, Hamadan City, Hamadan, Iran.
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Zhang W, Cao Y, Huang J, Zhao W, Liu X, Li M, Ji H. Ultrasonic-accelerated metallurgical reaction of Sn/Ni composite solder: Principle, kinetics, microstructure, and joint properties. Ultrason Sonochem 2020; 66:105090. [PMID: 32247233 DOI: 10.1016/j.ultsonch.2020.105090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Revised: 03/22/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
The high-melting-point joints by transient-liquid-phase are increasingly playing a crucial role in the die bonding for the high temperature electronic components. In this study, three kinds of Sn/Ni composite solder pastes composed of different sizes of Ni particles were synthesized to accelerate metallurgical reaction among Sn/Ni interfaces under the ultrasonic-assisted transient liquid phase (U-TLP) soldering. The temperature evolution, microstructure and mechanical property in joints composed by these composite solder pastes with or without ultrasonic energy were systemically investigated. The intermetallic joint consisted of high-melting-point sole Ni3Sn4 intermetallic compound with a little residual Ni was obtained under the conditions of no pressure and lower power (200 W) in a high-temperature duration of only 10 s, its shear strength was up to 45.3 MPa. Ultrasonic effects significantly accelerated the reaction among the interfaces of liquid Sn and solid Ni, which attributed to the temperature rise caused by acoustic cavitation because of large number of liquid/solid interfaces during U-TLP, resulting in accelerated solid/liquid interfacial diffusion and growth of intermetallic compounds. This intermetallic joint formed by U-TLP soldering has a promising potential for applications in high-power device packaging.
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Affiliation(s)
- Wenwu Zhang
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Yichen Cao
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Jiayi Huang
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Weiwei Zhao
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Xiangli Liu
- Shenzhen Engineering Laboratory of Aerospace Detection and Imaging, Department of Materials Science and Engineering, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Mingyu Li
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China
| | - Hongjun Ji
- State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, Guangdong, China; Flexible Printing Electronic Technology Center, Harbin Institute of Technology at Shenzhen, Shenzhen 518055, China.
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Sharafeddin F, Alavi AA, Siabani S, Safari M. Comparison of Shear Bond Strength of Three Types of Glass Ionomer Cements Containing Hydroxyapatite Nanoparticles to Deep and Superficial Dentin. J Dent (Shiraz) 2020; 21:132-140. [PMID: 32582829 PMCID: PMC7280551 DOI: 10.30476/dentjods.2019.77762.0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Statement of the Problem The clinical success of glass ionomer cement (GIC) restorations depends on the strength of its bonding to dentin, yet the bond strength of nanohydroxyapatite (nHAp) added GIC to dentin needs to be investigated. Purpose This study aimed to assess if the type of GIC containing nHAp and dentin depth could affect the shear bond strength (SBS). Materials and Method In this experimental study, 60 freshly extracted intact third molars were randomly divided into two main groups of flat occlusal dentin with different cuts as superficial (S); just below the dentinoenamel junction (DEJ) and deep (D); 2mm below DEJ. After conditioning with 20% polyacrylic acid, each group were randomly assigned to the tested GIC (n=10) subgroups as (1) Fuji IX Extra+nHAp, (2) Fuji II LC+nHAp and (3) Zirconomer+nHAp. Plastic tubes were placed on the pre-treated surfaces and filled with one of the GIC, then stored in an incubator at 37 oC and 100% humidity for 24hr. The specimens were thermocycled at5/55 oC for 500 cycles and subjected to SBS test using a universal testing machine (1 mm/min). The data analyzed by Mann-Whitney and Kruskal-Wallis test (p< 0.05). Results The means of SBS of Fuji II LC+nHAp was significantly higher than Fuji IX+nHAp and Zirconomer+nHAp both in superficial and deep dentin (p< 0.05). The means of SBS of Fuji IX Extra+nHAp and Zirconomer+nHAp subgroups in superficial dentin were higher than deep dentin, this differences was statistically significant (p= 0.0001 and p= 0.009, respectively). Conclusion It can conclude that SBS was influenced by type of GIC and depth of dentin.
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Affiliation(s)
- Farahnaz Sharafeddin
- Dept. of Operative Dentistry, Biomaterials Research Center, School of Dentistry, Shiraz University of Medial Sciences, Shiraz, Iran
| | - Ali Asghar Alavi
- Dept. of Operative Dentistry, Biomaterials Research Center, School of Dentistry, Shiraz University of Medial Sciences, Shiraz, Iran
| | - Saba Siabani
- Postgraduate Student, Dept. of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mina Safari
- Postgraduate Student, Dept. of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
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Valizadeh S, Alimohammadi G, Nik TH, Etemadi A, Tanbakuchi B. In vitro evaluation of shear bond strength of orthodontic metal brackets to aged composite using a self-adhesive composite: Effect of surface conditioning and different bonding agents. Int Orthod 2020; 18:528-537. [PMID: 32451267 DOI: 10.1016/j.ortho.2020.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/08/2020] [Accepted: 04/11/2020] [Indexed: 10/24/2022]
Abstract
OBJECTIVES Bracket bonding to composite surfaces is increasing. This study sought to assess the effect of different adhesives (acid etchant+Transbond XT™, acid etchant+Vertise Flow™, Vertise Flow™) with different surface treatments (no preparation, bur, sandblasting, Er:YAG laser) on shear bond strength (SBS) of metal brackets to aged composite. MATERIALS AND METHODS In this in vitro, experimental study, Filtek™ Z250 composite discs were fabricated (10×4mm). After thermocycling (10,000 cycles between 5-55°C), the samples were randomly divided into three groups (n=48) based on the type of adhesive namely acid etchant+Transbond XT™, Vertise Flow™, and acid etchant+Vertise Flow™. Samples in each group were randomly divided into four subgroups (n=12) based on the surface treatment including no-treatment, diamond bur, sandblasting and Er:YAG laser. Samples in each group were randomly divided into three subgroups (n=12) based on the type of adhesive namely acid etchant+Transbond XT™, Vertise Flow™, and acid etchant+Vertise Flow™. After bracket bonding to composite discs, the samples underwent thermocycling (5000 cycles between 5-55°C), and their SBS was measured in a universal testing machine. The samples were then inspected under a stereomicroscope at x10 magnification to determine their mode of failure and adhesive remnant index (ARI). RESULTS No significant difference was noted in SBS between adhesives in no-preparation and laser groups (P>0.05). In all adhesive groups, sandblast had highest SBS, but it was not significantly different in Vertise Flow™ groups, with and without etching. The SBS provided by acid etchant+Transbond XT™ was significantly higher than that of the other two adhesives (P<0.05). The SBS of sandblasted samples was significantly higher compared with other surface treatments in all adhesive subgroups (P<0.05). CONCLUSION Bracket bonding to aged composite using Vertise Flow™ with or without surface treatment can serve as an alternative to the conventional orthodontic adhesives.
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Affiliation(s)
- Sara Valizadeh
- Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Restorative Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Tahereh Hosseinzadeh Nik
- Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Ardavan Etemadi
- Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Periodontics, Faculty of Dentistry, Islamic Azad University, Tehran, Iran
| | - Behrad Tanbakuchi
- Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
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Anagnostopoulos CA, Chrysanidis T, Anagnostopoulou M. Experimental data of cement grouting in coarse soils with different superplasticisers. Data Brief 2020; 30:105612. [PMID: 32382618 PMCID: PMC7200773 DOI: 10.1016/j.dib.2020.105612] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 12/01/2022] Open
Abstract
High-range water reducers, such as superplasticisers, can be potentially viable for cement grouting applications. In this study, we investigate the influence of two types of superplasticisers—one based on polycarboxylate ether and another based on naphthalene condensates—on the injectability of thick cement grouts into coarse soil and on the shear strength parameters of the grouted soil. Injectability tests were performed on soil columns with various superplasticiser dosages and grouts prepared with different water-to-cement ratios over a wide range of grouting pressures. The shear strength parameters of the grouted soil were evaluated through undrained unconsolidated triaxial compression tests.
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Affiliation(s)
- Costas A Anagnostopoulos
- Department of Environmental Engineering, International Hellenic University, 57400 Sindos, Thessaloniki, Greece
| | - Theodoros Chrysanidis
- Department of Environmental Engineering, International Hellenic University, 57400 Sindos, Thessaloniki, Greece
| | - Maria Anagnostopoulou
- Department of Environmental Engineering, International Hellenic University, 57400 Sindos, Thessaloniki, Greece
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