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Abrahamsson C, Rissler J, Kåredal M, Hedmer M, Suchorzewski J, Prieto M, Chaudhari OA, Gudmundsson A, Isaxon C. Characterization of airborne dust emissions from three types of crushed multi-walled carbon nanotube-enhanced concretes. NANOIMPACT 2024; 34:100500. [PMID: 38382676 DOI: 10.1016/j.impact.2024.100500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 02/23/2024]
Abstract
Dispersing Multi-Walled Carbon Nanotubes (MWCNTs) into concrete at low (<1 wt% in cement) concentrations may improve concrete performance and properties and provide enhanced functionalities. When MWCNT-enhanced concrete is fragmented during remodelling or demolition, the stiff, fibrous and carcinogenic MWCNTs will, however, also be part of the respirable particulate matter released in the process. Consequently, systematic aerosolizing of crushed MWCNT-enhanced concretes in a controlled environment and measuring the properties of this aerosol can give valuable insights into the characteristics of the emissions such as concentrations, size range and morphology. These properties impact to which extent the emissions can be inhaled as well as where they are expected to deposit in the lung, which is critical to assess whether these materials might constitute a future health risk for construction and demolition workers. In this work, the impact from MWCNTs on aerosol characteristics was assessed for samples of three concrete types with various amounts of MWCNT, using a novel methodology based on the continuous drop method. MWCNT-enhanced concretes were crushed, aerosolized and the emitted particles were characterized with online and offline techniques. For light-weight porous concrete, the addition of MWCNT significantly reduced the respirable mass fraction (RESP) and particle number concentrations (PNC) across all size ranges (7 nm - 20 μm), indicating that MWCNTs dampened the fragmentation process by possibly reinforcing the microstructure of brittle concrete. For normal concrete, the opposite could be seen, where MWCNTs resulted in drastic increases in RESP and PNC, suggesting that the MWCNTs may be acting as defects in the concrete matrix, thus enhancing the fragmentation process. For the high strength concrete, the fragmentation decreased at the lowest MWCNT concentration, but increased again for the highest MWCNT concentration. All tested concrete types emitted <100 nm particles, regardless of CNT content. SEM imaging displayed CNTs protruding from concrete fragments, but no free fibres were detected.
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Affiliation(s)
- Camilla Abrahamsson
- Division of Ergonomics and Aerosol Technology, Lund University, Lund 221 00, Sweden; NanoLund, Lund University, Box 118, Lund 221 00, Sweden.
| | - Jenny Rissler
- Division of Ergonomics and Aerosol Technology, Lund University, Lund 221 00, Sweden; NanoLund, Lund University, Box 118, Lund 221 00, Sweden; Research Institutes of Sweden, Lund 223 63, Sweden
| | - Monica Kåredal
- NanoLund, Lund University, Box 118, Lund 221 00, Sweden; Division of Occupational and Environmental Medicine, Department of Laboratory Medicine, Lund University, Lund 221 00, Sweden; Department of Occupational and Environmental Medicine, Region Skåne, Lund 223 81, Sweden
| | - Maria Hedmer
- NanoLund, Lund University, Box 118, Lund 221 00, Sweden; Division of Occupational and Environmental Medicine, Department of Laboratory Medicine, Lund University, Lund 221 00, Sweden; Department of Occupational and Environmental Medicine, Region Skåne, Lund 223 81, Sweden
| | - Jan Suchorzewski
- Research Institutes of Sweden, Infrastructure and Concrete Technology, Material Design, Borås 501 15, Sweden
| | - Miguel Prieto
- Research Institutes of Sweden, Infrastructure and Concrete Technology, Material Design, Borås 501 15, Sweden
| | - Ojas Arun Chaudhari
- Research Institutes of Sweden, Infrastructure and Concrete Technology, Material Design, Borås 501 15, Sweden
| | - Anders Gudmundsson
- Division of Ergonomics and Aerosol Technology, Lund University, Lund 221 00, Sweden; NanoLund, Lund University, Box 118, Lund 221 00, Sweden
| | - Christina Isaxon
- Division of Ergonomics and Aerosol Technology, Lund University, Lund 221 00, Sweden; NanoLund, Lund University, Box 118, Lund 221 00, Sweden
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2
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Jadoon L, Gul A, Fatima H, Babar MM. Nano-elicitation and hydroponics: a synergism to enhance plant productivity and secondary metabolism. PLANTA 2024; 259:80. [PMID: 38436711 DOI: 10.1007/s00425-024-04353-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 01/26/2024] [Indexed: 03/05/2024]
Abstract
MAIN CONCLUSION This review has explored the importance of using a synergistic approach of nano-elicitation and hydroponics to improve plant growth and metabolite production. Furthermore, it emphasizes the significance of green nanotechnology and eco-friendly practices while utilizing this approach to promote the development of a sustainable agriculture system. Nano-elicitation stimulates metabolic processes in plants using nanoparticles (NPs) as elicitors. The stimulation of these biochemical processes can enhance plant yield and productivity, along with the production of secondary metabolites. Nanoparticles have garnered the attention of scientific community because of their unique characteristics, such as incredibly small size and large surface-to-volume ratio, which make them effective elicitors. Hydroponic systems, which optimize growing conditions to increase plant production, are typically used to study the effect of elicitors. By integrating these two approaches, the qualitative and quantitative output of plants can be increased while employing minimal resources. As the global demand for high-quality crops and bioactive compounds surges, embracing this synergistic approach alongside sustainable farming practices can pave the way for resilient agricultural systems, ensuring food security and fostering an eco-friendly environment.
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Affiliation(s)
- Linta Jadoon
- Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, 44000, Pakistan
| | - Alvina Gul
- Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, 44000, Pakistan.
| | - Hunaiza Fatima
- Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, 44000, Pakistan
| | - Mustafeez Mujtaba Babar
- Shifa College of Pharmaceutical Sciences, Shifa Tameer-e-Millat University, Islamabad, 44000, Pakistan.
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Tziviloglou E, Metaxa ZS, Maistros G, Kourkoulis SK, Karousos DS, Favvas EP, Alexopoulos ND. Electrochemical Impedance as an Assessment Tool for the Investigation of the Physical and Mechanical Properties of Graphene-Based Cementitious Nanocomposites. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2652. [PMID: 37836293 PMCID: PMC10574441 DOI: 10.3390/nano13192652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/19/2023] [Accepted: 09/24/2023] [Indexed: 10/15/2023]
Abstract
This investigation explores the potential of electrochemical impedance spectroscopy (EIS) in evaluating graphene-based cementitious nanocomposites, focusing on their physical and structural properties, i.e., electrical resistivity, porosity, and fracture toughness. EIS was employed to study cement mixtures with varying graphene nanoplatelet (xGnP) concentrations (0.05-0.40% per dry cement weight), whereas flexural tests assessed fracture toughness and porosimetry analyses investigated the structural characteristics. The research demonstrated that the electrical resistivity initially decreased with increasing xGnP content, leveling off at higher concentrations. The inclusion of xGnPs correlated with an increase in the total porosity of the cement mixtures, which was indicated by both EIS and porosimetry measurements. Finally, a linear correlation emerged between fracture toughness and electrical resistivity, contributing also to underscore the use of EIS as a potent non-destructive tool for evaluating the physical and mechanical properties of conductive nano-reinforced cementitious nanocomposites.
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Affiliation(s)
- Eirini Tziviloglou
- Research Unit of Advanced Materials, Department of Financial and Management Engineering, University of the Aegean, 82132 Chios, Greece
| | - Zoi S Metaxa
- Department of Chemistry, International Hellenic University, 65404 Kavala, Greece
| | | | - Stavros K Kourkoulis
- Department of Mechanics, National Technical University of Athens, 15780 Athens, Greece
| | - Dionysios S Karousos
- Research Unit of Advanced Materials, Department of Financial and Management Engineering, University of the Aegean, 82132 Chios, Greece
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Patr. Gregoriou E & 27 Neapoleos Str., 15341 Agia Paraskevi, Greece
| | - Evangelos P Favvas
- Institute of Nanoscience and Nanotechnology, N.C.S.R. "Demokritos", Patr. Gregoriou E & 27 Neapoleos Str., 15341 Agia Paraskevi, Greece
| | - Nikolaos D Alexopoulos
- Research Unit of Advanced Materials, Department of Financial and Management Engineering, University of the Aegean, 82132 Chios, Greece
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Saleem H, Saud A, Zaidi SJ. Sustainable Preparation of Graphene Quantum Dots from Leaves of Date Palm Tree. ACS OMEGA 2023; 8:28098-28108. [PMID: 37576687 PMCID: PMC10413365 DOI: 10.1021/acsomega.3c00694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 07/03/2023] [Indexed: 08/15/2023]
Abstract
The date palm (Phoenix dactylifera), a subtropical and tropical tree, included in the family Palmae (Arecaceae) is one of the oldest cultivated plants of mankind. Date palm is a major agricultural product in the semi-arid and arid areas of the world, particularly in Arab countries. These trees generate high quantities of agricultural waste in the form of dry leaves, seeds, etc. In this study, dried date palm leaves were used as green precursors for synthesizing graphene quantum dots (GQDs). This work reported the preparation of GQDs using two different sustainable methods. GQD-1 was developed using a simple, hydrothermal technique at 200 °C for 12 h in water, with no requirement of reducing or passivizing agents or organic solvents. GQD-2 was prepared using a hydrothermal technique at 200 °C for 12 h in water, with the usage of just distilled water and absolute ethanol. The compositional analysis of the leaf extract was performed, along with the morphological, compositional, and optical examination of the sustainably developed GQDs. The characterization results confirmed the successful formation of GQDs, with average sizes ranging from 3.5 to 8 nm. This study helps to obtain GQDs in an economical, eco-friendly, and biocompatible manner and can assist in large-scale production and in recycling date palm tree waste products from Middle East countries into value-added products.
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Affiliation(s)
- Haleema Saleem
- UNESCO Chair on Desalination
and Water Treatment, Center for Advanced Materials, Qatar University, Doha 2713, Qatar
| | - Asif Saud
- UNESCO Chair on Desalination
and Water Treatment, Center for Advanced Materials, Qatar University, Doha 2713, Qatar
| | - Syed Javaid Zaidi
- UNESCO Chair on Desalination
and Water Treatment, Center for Advanced Materials, Qatar University, Doha 2713, Qatar
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Xu H, Tang Z, Yang D, Dai X, Chen H. Enhanced growth and auto-flocculation of Scenedesmus quadricauda in anaerobic digestate using high light intensity and nanosilica: A biomineralization-inspired strategy. WATER RESEARCH 2023; 235:119893. [PMID: 36989808 DOI: 10.1016/j.watres.2023.119893] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/03/2023] [Accepted: 03/17/2023] [Indexed: 06/19/2023]
Abstract
Coupling municipal anaerobic digestate (MAD) treatments with microalgal cultivation can concomitantly achieve nutrient removal and microalgal bioenergy production. However, the high cost caused by dilution water and microalgal harvesting is a great challenge. In this study, Scenedesmus quadricauda was screened as the most appropriate algae strain due to its potential for growth and auto-flocculation, and the MAD diluted 5-fold with WWTP effluent was demonstrated as an ideal medium for S. quadricauda growth. Moreover, inspired by naturally generated silica shells of diatoms, a low-cost and biomimetic auto-flocculation strategy that combined high light intensity induction and microalgal silicification was proposed to accelerate the auto-flocculation process. Compared with low light intensity groups, this strategy imparted diatom-like features to S. quadricauda cells, and contributed to 3.07-fold higher auto-flocculation efficiency within 30 min. It was attributed to the fact that the high light intensity of 150 μmol·m - 2·s - 1 stimulated the extracellular polymeric substances (EPS) secretion and induced the variation in property and composition of EPS, especially the protein secondary structures, which allowed silica nanoparticles to spontaneously attach onto S. quadricauda cells in the presence of viscous EPS. Furthermore, this strategy significantly increased microalgal biomass yield to a dry weight of 1.37 g·L - 1, accompanied by 93.78%, 96.39% and 91.36% removals of NH4+-N, TP, and COD, respectively. The productivity of valuable by-products, including lipid, carbohydrate, protein, and pigment, reached 56.30, 101.35, 30.39 and 11.28 mg·L - 1·d - 1, respectively. Overall, this study supplies a novel approach for low-cost microalgal bioenergy production from MAD and energy-efficient microalgae harvest by auto-flocculation.
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Affiliation(s)
- Haolian Xu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhenzhen Tang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Donghai Yang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Hongbin Chen
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
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Saleem H, Goh PS, Saud A, Khan MAW, Munira N, Ismail AF, Zaidi SJ. Graphene Quantum Dot-Added Thin-Film Composite Membrane with Advanced Nanofibrous Support for Forward Osmosis. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12234154. [PMID: 36500777 PMCID: PMC9735732 DOI: 10.3390/nano12234154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/01/2022] [Accepted: 11/10/2022] [Indexed: 05/17/2023]
Abstract
Forward osmosis (FO) technology for desalination has been extensively studied due to its immense benefits over conventionally used reverse osmosis. However, there are some challenges in this process such as a high reverse solute flux (RSF), low water flux, and poor chlorine resistance that must be properly addressed. These challenges in the FO process can be resolved through proper membrane design. This study describes the fabrication of thin-film composite (TFC) membranes with polyethersulfone solution blown-spun (SBS) nanofiber support and an incorporated selective layer of graphene quantum dots (GQDs). This is the first study to sustainably develop GQDs from banyan tree leaves for water treatment and to examine the chlorine resistance of a TFC FO membrane with SBS nanofiber support. Successful GQD formation was confirmed with different characterizations. The performance of the GQD-TFC-FO membrane was studied in terms of flux, long-term stability, and chlorine resistance. It was observed that the membrane with 0.05 wt.% of B-GQDs exhibited increased surface smoothness, hydrophilicity, water flux, salt rejection, and chlorine resistance, along with a low RSF and reduced solute flux compared with that of neat TFC membranes. The improvement can be attributed to the presence of GQDs in the polyamide layer and the utilization of SBS nanofibrous support in the TFC membrane. A simulation study was also carried out to validate the experimental data. The developed membrane has great potential in desalination and water treatment applications.
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Affiliation(s)
- Haleema Saleem
- UNESCO Chair on Desalination and Water Treatment, Center for Advanced Materials (CAM), Qatar University, Doha P.O. Box 2713, Qatar
| | - Pei Sean Goh
- Advanced Membrane Technology Research Centre, School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
| | - Asif Saud
- UNESCO Chair on Desalination and Water Treatment, Center for Advanced Materials (CAM), Qatar University, Doha P.O. Box 2713, Qatar
| | - Mohammad Aquib Wakeel Khan
- UNESCO Chair on Desalination and Water Treatment, Center for Advanced Materials (CAM), Qatar University, Doha P.O. Box 2713, Qatar
| | - Nazmin Munira
- UNESCO Chair on Desalination and Water Treatment, Center for Advanced Materials (CAM), Qatar University, Doha P.O. Box 2713, Qatar
| | - Ahmad Fauzi Ismail
- Advanced Membrane Technology Research Centre, School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
| | - Syed Javaid Zaidi
- UNESCO Chair on Desalination and Water Treatment, Center for Advanced Materials (CAM), Qatar University, Doha P.O. Box 2713, Qatar
- Correspondence: ; Tel.: +974-4403-7723
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Ikram R, Jan BM, Ahmad W, Sidek A, Khan M, Kenanakis G. Rheological Investigation of Welding Waste-Derived Graphene Oxide in Water-Based Drilling Fluids. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8266. [PMID: 36431754 PMCID: PMC9696946 DOI: 10.3390/ma15228266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 06/16/2023]
Abstract
Throughout the world, the construction industry produces significant amounts of by-products and hazardous waste materials. The steel-making industry generates welding waste and dusts that are toxic to the environment and pose many economic challenges. Water-based drilling fluids (WBDF) are able to remove the drill cuttings in a wellbore and maintain the stability of the wellbore to prevent formation damage. To the best of our knowledge, this is the first study that reports the application of welding waste and its derived graphene oxide (GO) as a fluid-loss additive in drilling fluids. In this research, GO was successfully synthesized from welding waste through chemical exfoliation. The examination was confirmed using XRD, FTIR, FESEM and EDX analyses. The synthesized welding waste-derived GO in WBDF is competent in improving rheological properties by increasing plastic viscosity (PV), yield point (YP) and gel strength (GS), while reducing filtrate loss (FL) and mud cake thickness (MCT). This study shows the effect of additives such as welding waste, welding waste-derived GO and commercial GO, and their amount, on the rheological properties of WBDF. Concentrations of these additives were used at 0.01 ppb, 0.1 ppb and 0.5 ppb. Based on the experiment results, raw welding waste and welding waste-derived GO showed better performance compared with commercial GO. Among filtration properties, FL and MCT were reduced by 33.3% and 39.7% with the addition of 0.5 ppb of raw welding-waste additive, while for 0.5 ppb of welding waste-derived GO additive, FL and MCT were reduced by 26.7% and 20.9%, respectively. By recycling industrial welding waste, this research conveys state-of-the-art and low-cost drilling fluids that aid in waste management, and reduce the adverse environmental and commercial ramifications of toxic wastes.
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Affiliation(s)
- Rabia Ikram
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Badrul Mohamed Jan
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Waqas Ahmad
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pukhtunkhwa, Pakistan
| | - Akhmal Sidek
- Petroleum Engineering Department, School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
| | - Mudasar Khan
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pukhtunkhwa, Pakistan
| | - George Kenanakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, N. Plastira 100, Vasilika Vouton, GR-700 13 Heraklion, Crete, Greece
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Nanomodified Concrete with Enhanced Characteristics Based on River Snail Shell Powder. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12157839] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The utilization of aquaculture waste, such as snail shells, is a severe issue. These shells are common in water-sources and are a by-product of sifting sand for masonry and concrete work. Calcium-rich river shells are of great interest for cement building materials. In this regard, the purpose of this article was to develop a nanomodified concrete with improved characteristics based on the powder of snail shells. Experimental studies have confirmed the effectiveness of the use of river shells in concrete without a decrease in strength characteristics and deterioration of other properties. It has been found that the optimal replacement by the snail shell powder that replaced cement is in the amount of 6%. By the nanomodification of concrete with the powdered shells of river snails, it was possible to achieve an increase in compressive strength up to 12%, axial compressive strength—up to 8%, tensile strength in bending—up to 9%, axial tensile strength—up to 11%, elastic modulus—up to 8%. Concrete nanomodification with snail shell powder in the amount of 6% contributed to a reduction of deformations of up to 7%. The study of the microstructure of concrete samples nanomodified with snail shell powder confirmed the obtained dependences of the cement’s properties on the nanomodifier dosage, as well as the most effective dosage of snail shell powder.
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Influence of a Novel Carbon-Based Nano-Material on the Thermal Conductivity of Mortar. SUSTAINABILITY 2022. [DOI: 10.3390/su14138189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The paper presents the results of research work to assess the thermal conductivity of mortar incorporating a novel carbon-based nano-material (CBN). The data from the laboratory tests served as the starting point in training an artificial neural network (ANN) based on the Levenberg–Marquardt backpropagation algorithm that was used to predict the values of the thermal conductivity at later ages. The used CBNs were essential precursors of multi-walled carbon nano-tubes but different from their counterparts in the fact that they were capped at the ends. This configuration should result in lower surface tension and should prevent the bundling even without the use of surfactants and sonication. The obtained results show that the mortar mixes with CBN exhibit higher values for the thermal coefficient at early ages compared to the reference mix, even at very low percentages of CBN by weight of cement. The ANN is able to accurately predict the experimental results both at 28 days and at later ages. The obtained results should serve as the starting point for further investigations into the microstructure of cement-based materials enhanced with CBNs.
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Enhanced Eco-Friendly Concrete Nano-Change with Eggshell Powder. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12136606] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
One of the unifying factors for all countries is the large consumption of chicken, and other, eggs in food and other types of economic activity. After using various types of eggs for their intended purpose, a large amount of waste accumulates in the form of eggshells. Currently, this problem exists and needs a non-trivial, original solution. The aim of the work was to fill the scientific gap in the direction of studying the microstructure formation of improved nano-modified environmentally-friendly concrete based on eggshell powder and obtaining a concrete composition for the manufacture of an industrial sample of such a material. An environmentally-friendly concrete was obtained, the characteristics of which were improved relative to standard concrete by modifying it with eggshell powder, for which the optimal dosage was determined. The most effective was the replacement of part of the cement with eggshell powder in the amount of 10%. The maximum increase in strength characteristics ranged from 8% to 11%. The modulus of elasticity increased by 4% compared to the control samples without eggshell powder. The maximum reduction in deformations under axial compression and tension in comparison with the control values ranged from 5% to 10%. The study of the composite’s microstructure nano-modified with eggshell powder, and an analysis of the changes occurring in this microstructure due to nano-modification, confirmed the improvement in characteristics and the optimal dosage of eggshell powder.
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