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Bernasowski M, Migas P, Ślęzak M, Gondek Ł, Cieniek Ł. Utilization of High-Zn Content Ferrous Landfill Sludge with the Use of Hydrogen. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7676. [PMID: 38138818 PMCID: PMC10745102 DOI: 10.3390/ma16247676] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023]
Abstract
Sludge, due to its form and significant moisture and zinc content, is the most problematic metallurgical waste. Near the site of a disused steelworks plant in Krakow (Poland) there is an estimated 5 million tonnes of landfill sludge that consists of more than 90% iron and other metal oxides. There is a global tendency to switch steel production towards carbonless technologies, which is why the presented work investigates the possibility of simultaneous waste liquidation and recovery of valuable metals with the use of hydrogenous reduction. Direct reduced iron (DRI) production was selected as the targeted technology, so the sludge was lumped and bound with cement or CaO addition. The obtained lumps were reduced in a hydrogenous atmosphere with gradual heating to 950 °C, after which their phase structure was analyzed and elemental analysis was performed. It was found that zinc evaporated during the experiment, but mostly thanks to the carbon contained in the sludge. The increased addition of binder to the sludge resulted in the enhancement of the lumps, but also limited the reduction range. The products obtained were mostly wustite and less pure iron. Taking into account the degree of reduction and the lumps' compression strength, the best binding was achieved by adding cement at a quantity of 5% mass.
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Pudełko-Prażuch I, Balasubramanian M, Ganesan SM, Marecik S, Walczak K, Pielichowska K, Chatterjee S, Kandaswamy R, Pamuła E. Characterization and In Vitro Evaluation of Porous Polymer-Blended Scaffolds Functionalized with Tricalcium Phosphate. J Funct Biomater 2024; 15:57. [PMID: 38535250 PMCID: PMC10970789 DOI: 10.3390/jfb15030057] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 02/16/2024] [Accepted: 02/22/2024] [Indexed: 11/11/2024] Open
Abstract
Bone tissue is one of the most transplanted tissues. The ageing population and bone diseases are the main causes of the growing need for novel treatments offered by bone tissue engineering. Three-dimensional (3D) scaffolds, as artificial structures that fulfil certain characteristics, can be used as a temporary matrix for bone regeneration. In this study, we aimed to fabricate 3D porous polymer scaffolds functionalized with tricalcium phosphate (TCP) particles for applications in bone tissue regeneration. Different combinations of poly(lactic acid) (PLA), poly(ethylene glycol) (PEG with molecular weight of 600 or 2000 Da) and poly(ε-caprolactone) (PCL) with TCP were blended by a gel-casting method combined with rapid heating. Porous composite scaffolds with pore sizes from 100 to 1500 µm were obtained. ATR-FTIR, DSC, and wettability tests were performed to study scaffold composition, thermal properties, and hydrophilicity, respectively. The samples were observed with the use of optical and scanning electron microscopes. The addition of PCL to PLA increased the hydrophobicity of the composite scaffolds and reduced their susceptibility to degradation, whereas the addition of PEG increased the hydrophilicity and degradation rates but concomitantly resulted in enhanced creation of rounded mineral deposits. The scaffolds were not cytotoxic according to an indirect test in L929 fibroblasts, and they supported adhesion and growth of MG-63 cells when cultured in direct contact.
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Kopyściański M, Dymek S, Hamilton C, Węglowska A, Kalemba-Rec I. Microstructural Characterization of Friction Stir Welds of Aluminum 6082 Produced with Bobbin Tool. MATERIALS (BASEL, SWITZERLAND) 2024; 17:4738. [PMID: 39410309 PMCID: PMC11478122 DOI: 10.3390/ma17194738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2024] [Revised: 09/20/2024] [Accepted: 09/24/2024] [Indexed: 10/20/2024]
Abstract
This study utilized a bobbin tool to friction stir weld aluminum 6082 workpieces under two sets of process parameters: a tool rotation speed of 280 rev/min with a weld velocity of 280 mm/min (280/280) and a tool rotation speed of 450 rev/min with a weld velocity of 450 mm/min (450/450). The weld microstructures were characterized through optical microscopy utilizing polarized light and through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled with chemical analysis by energy dispersive spectroscopy and electron back scatter diffraction. The microstructural studies were supplemented by hardness measurements (Vickers) performed on the same sections as the metallographic examinations. The produced weldments were free from cracks and any discontinuities. Fine, equiaxed grains that were several microns in size characterized the stir zones (SZs), and the advancing (AS) and retreating (RS) sides revealed distinct microstructural features. On the AS, the transition from the thermo-mechanically affected zone to the SZ was well defined and sharp, but on the RS, the transition appeared as a continuous, gradual change in microstructure. The lower weld energy (280/280) produced lower hardness in the stir zone than the higher energy weld (450/450), ~95 HV1 versus ~115 HV1; however, the 280/280 welds showed higher tensile strengths than the 450/450 welds, ~238 MPa as opposed to ~172 MPa. These behaviors in mechanical performance correlated with the temperature histories produced by each set of weld parameters in relation to the precipitation behavior of the alloy. The fracture characteristics of the weldments were notably different with the 450/450 sample fracturing in a quasi-brittle manner with slight plastic deformation and the 280/280 sample fracturing ductilely. A numerical simulation supported the investigation by elucidating the temperature and material flow behavior during the joining process.
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Sinelnikov V, Kalisz D, Novosád J, Czarnywojtek P, Rapiejko C, Niedzielski P, Kaczorowski R, Srb P, Maia BT, Petrů M, Łoś Buczkowska KE. Analysis of the Influence of Different Diameters of De Laval Supersonic Nozzles on the Key Splashing Parameters of Remaining Slag. MATERIALS (BASEL, SWITZERLAND) 2024; 17:5796. [PMID: 39685232 DOI: 10.3390/ma17235796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2024] [Revised: 11/12/2024] [Accepted: 11/18/2024] [Indexed: 12/18/2024]
Abstract
The paper is devoted to the analysis of a supersonic nozzle system effect in gas-cooled lances on the technological parameters of slag splashing in an oxygen converter. Simulation calculations were carried out, taking into account the parameters of nozzles used in the technological lines of converter steel plants in Ukraine and Brazil. The problems were solved in several stages. The simulation results of the first stage revealed the influence of different nozzle diameters dcr, dex and the inlet pressure before nozzle P0 on the nitrogen consumption of one nozzle Vн. Calculations also showed the influence of the critical dcr and output dex of the nozzle diameter and nitrogen flow through one nozzle Vн on the power of injected nitrogen N1 and the depth of penetration of the stream hx into the liquid slag. The second stage was dedicated to numerical simulation of the slag splashing process, including an array of results from the first stage. The thermodynamic and physical parameters were calculated using our own computer program, while 3D simulations were conducted using the ANSYS Fluent 2023 R2 program.
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Orzechowska A, Czaderna-Lekka A, Trtílek M, Szymańska R, Trela-Makowej A, Wątor K. Novel technique for the ultra-sensitive detection of hazardous contaminants using an innovative sensor integrated with a bioreactor. Sci Rep 2024; 14:12836. [PMID: 38834660 DOI: 10.1038/s41598-024-63631-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/30/2024] [Indexed: 06/06/2024] Open
Abstract
This study introduces an evaluation methodology tailored for bioreactors, with the aim of assessing the stress experienced by algae due to harmful contaminants released from antifouling (AF) paints. We present an online monitoring system equipped with an ultra-sensitive sensor that conducts non-invasive measurements of algal culture's optical density and physiological stage through chlorophyll fluorescence signals. By coupling the ultra-sensitive sensor with flash-induced chlorophyll fluorescence, we examined the dynamic fluorescence changes in the green microalga Chlamydomonas reinhardtii when exposed to biocides. Over a 24-h observation period, increasing concentrations of biocides led to a decrease in photosynthetic activity. Notably, a substantial reduction in the maximum quantum yield of primary photochemistry (FV/FM) was observed within the first hour of exposure. Subsequently, we detected a partial recovery in FV/FM; however, this recovery remained 50% lower than that of the controls. Integrating the advanced submersible sensor with fluorescence decay kinetics offered a comprehensive perspective on the dynamic alterations in algal cells under the exposure to biocides released from antifouling coatings. The analysis of fluorescence relaxation kinetics revealed a significant shortening of the fast and middle phases, along with an increase in the duration of the slow phase, for the coating with the highest levels of biocides. Combining automated culturing and measuring methods, this approach has demonstrated its effectiveness as an ultrasensitive and non-invasive tool for monitoring the physiology of photosynthetic cultures. This is particularly valuable in the context of studying microalgae and their early responses to various environmental conditions, as well as the potential to develop an AF system with minimal harm to the environment.
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Sycińska-Dziarnowska M, Ziąbka M, Cholewa-Kowalska K, Klesiewicz K, Spagnuolo G, Lindauer SJ, Park HS, Woźniak K. Antibacterial and Antibiofilm Activity of Layers Enriched with Silver Nanoparticles on Orthodontic Microimplants. J Funct Biomater 2025; 16:78. [PMID: 40137357 PMCID: PMC11942985 DOI: 10.3390/jfb16030078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2025] [Revised: 02/02/2025] [Accepted: 02/21/2025] [Indexed: 03/27/2025] Open
Abstract
Orthodontic microimplants have revolutionized anchorage in orthodontics but remain vulnerable to microbial colonization, potentially leading to infection and failure. Surface modifications incorporating silver nanoparticles (AgNPs) offer antimicrobial benefits, providing long-term protection against bacterial infections, while improving partial osseointegration. This study investigates hybrid coatings enriched with AgNPs, calcium (Ca), and phosphorus (P) to improve antimicrobial efficacy and reduce biofilm formation. Microimplants fabricated from the Ti6Al4V alloy were divided into six groups with varying surface treatments, including etching in hydrofluoric acid and hybrid layers containing 0.5 mol% AgNPs and CaP. Antibacterial activity was evaluated using agar diffusion and biofilm formation assays against S. aureus, E. coli, and S. mutans. Surface roughness was analyzed and correlated with biofilm formation. The model assessing the impact of biomaterials on S. aureus biofilm revealed a strong association (R2 = 0.94), with biomaterial choice significantly influencing biofilm formation. The model for E. coli biofilm exhibited exceptional predictability (R2 = 0.99). The model for S. mutans biofilm demonstrated an association (R2 = 0.68). Hybrid coatings exhibited a promising antimicrobial activity. Biofilm formation was higher on microimplants with rougher surfaces. Hybrid coatings enriched with AgNPs and CaP enhance antimicrobial properties and partially reduce biofilm formation. It is suggested that the optimization of microimplant surface areas varies according to function. An enhanced performance can be achieved by maintaining a smooth surface for soft tissue contact, while incorporating a rough surface enriched with bactericidal and bioactive modifiers for bone contact areas.
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Chruszcz-Lipska K, Szostak E. A Study of the Structure of an Anion Exchange Resin with a Quaternary Ammonium Functional Group by Using Infrared Spectroscopy and DFT Calculations. MATERIALS (BASEL, SWITZERLAND) 2024; 17:6132. [PMID: 39769733 PMCID: PMC11676851 DOI: 10.3390/ma17246132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2024] [Revised: 12/09/2024] [Accepted: 12/12/2024] [Indexed: 01/11/2025]
Abstract
The large numbers of ion exchange resins used in various industries (food, pharmaceutitics, mining, hydrometallurgy), and especially in water treatment, are based on cross-linked polystyrene and divinylbenzene copolymers with functional groups capable of ion exchange. Their advantage, which makes them environmentally friendly, is the possibility of their regeneration and reuse. Taking into account the wide application of these materials, styrene-divinylbenzene resin with a quaternary ammonium functional group, Amberlite®IRA402, was characterized using a well-known and widely used method, FT-IR spectroscopy. As the infrared spectrum of the tested ion exchange resin was rich in bands, its detailed assignment was supported by quantum chemical calculations (DFT/B3LYP/6-31g** and DFT/PCM/B3LYP/6-31g**). Using appropriate 3D models of the resin structure, the optimization of geometry, the infrared spectrum and atomic charges from an atomic polar tensor (APT) were calculated. A detailed description of the infrared spectrum of Amberlite®IRA402 resin (Cl- form) in the spectral range of 4000-700 cm-1 was performed for the first time. The charge distribution on individual fragments of the resin structure in aqueous solution was also calculated for the first time. These studies will certainly allow for a better understanding of the styrene-divinylbenzene resin interaction in various processes with other substances, particularly in sorption processes.
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Kasprzyk M, Opiła G, Hinz A, Stankiewicz S, Bzowska M, Wolski K, Dulińska-Litewka J, Przewoźnik J, Kapusta C, Karewicz A. Hyaluronic Acid-Coated SPIONs with Attached Folic Acid as Potential T2 MRI Contrasts for Anticancer Therapies. ACS APPLIED MATERIALS & INTERFACES 2025; 17:9059-9073. [PMID: 39880388 PMCID: PMC11826879 DOI: 10.1021/acsami.4c20101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2024] [Revised: 12/29/2024] [Accepted: 12/29/2024] [Indexed: 01/31/2025]
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) are known to be good MRI contrasts, but they have a high tendency to aggregate and their biocompatibility is limited. Hyaluronic acid is highly biocompatible, can provide SPION with colloidal stability, and interacts specifically with tumor cells through the CD44 receptor; therefore, it was used as a stabilizing layer. We successfully obtained SPION coated with hyaluronic acid and further functionalized it with folic acid to construct a dual-targeted system. The physicochemical properties of the nanoparticles were investigated using DLS/ELS, AFM, XRD, and ATR-FTIR. Their magnetic characterization was performed by magnetometry, Mössbauer spectroscopy, 1H NMR T1 and T2 measurements, and MRI. The nanoparticles' biocompatibility was verified on blood and hepatocytes, and their cytotoxicity was tested on glioma and adenocarcinoma cells using the MTT assay. The nanoparticles were spherical, colloidally stable, and had low dispersity. Their cores were formed by 7 nm crystallites of magnetite in its oxidized form, maghemite. Our SPIONs were superparamagnetic and could potentially serve as effective T2 contrasts for MRI. The performance of SPIONs modified with folic acid was superior to that observed for commercial contrasts. Our nanoparticles were also hemocompatible and were efficiently taken up by glioblastoma cancer cells. Folic acid-modified SPIONs could also reduce viability of tumor cells in a dose-dependent manner. Thus, the proposed system has potential application as both a diagnostic tool and a therapeutic agent for targeted anticancer therapies.
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Pierpaoli M, Jakóbczyk P, Ficek M, Dec B, Ryl J, Rutkowski B, Lewkowicz A, Bogdanowicz R. Tailoring Defects in B, N-Codoped Carbon Nanowalls for Direct Electrochemical Oxidation of Glyphosate and its Metabolites. ACS APPLIED MATERIALS & INTERFACES 2024; 16:36784-36795. [PMID: 38967626 PMCID: PMC11261608 DOI: 10.1021/acsami.4c04478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 07/06/2024]
Abstract
Tailoring the defects in graphene and its related carbon allotropes has great potential to exploit their enhanced electrochemical properties for energy applications, environmental remediation, and sensing. Vertical graphene, also known as carbon nanowalls (CNWs), exhibits a large surface area, enhanced charge transfer capability, and high defect density, making it suitable for a wide range of emerging applications. However, precise control and tuning of the defect size, position, and density remain challenging; moreover, due to their characteristic labyrinthine morphology, conventional characterization techniques and widely accepted quality indicators fail or need to be reformulated. This study primarily focuses on examining the impact of boron heterodoping and argon plasma treatment on CNW structures, uncovering complex interplays between specific defect-induced three-dimensional nanostructures and electrochemical performance. Moreover, the study introduces the use of defect-rich CNWs as a label-free electrode for directly oxidizing glyphosate (GLY), a common herbicide, and its metabolites (sarcosine and aminomethylphosphonic acid) for the first time. Crucially, we discovered that the presence of specific boron bonds (BC and BN), coupled with the absence of Lewis-base functional groups such as pyridinic-N, is essential for the oxidation of these analytes. Notably, the D+D* second-order combinational Raman modes at ≈2570 cm-1 emerged as a reliable indicator of the analytes' affinity. Contrary to expectations, the electrochemically active surface area and the presence of oxygen-containing functional groups played a secondary role. Argon-plasma post-treatment was found to adversely affect both the morphology and surface chemistry of CNWs, leading to an increase in sp3-hybridized carbon, the introduction of oxygen, and alterations in the types of nitrogen functional groups. Simulations support that certain defects are functional for GLY rather than AMPA. Sarcosine oxidation is the least affected by defect type.
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Lenar N, Piech R, Paczosa-Bator B. A New Planar Potentiometric Sensor for In Situ Measurements. SENSORS (BASEL, SWITZERLAND) 2024; 24:2492. [PMID: 38676109 PMCID: PMC11054197 DOI: 10.3390/s24082492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024]
Abstract
A new construction of a potentiometric sensor was introduced for the first time. It relies on the use of two membranes instead of one, as in the well-known coated-disc electrode. For this purpose, a new electrode body was constructed, including not one, but two glassy carbon discs covered with an ion-selective membrane. This solution allows for the sensor properties to be enhanced without using additional materials (layers or additives) on the membrane. The new construction is particularly useful for in situ measurements in environmental samples. Two ion-selective polymeric membranes were used, namely H+ and K+-selective membranes, to confirm the universality of the idea. The tests conducted included chronopotentiometric tests, electrochemical impedance spectroscopy, and potentiometric measurements. The electrical and analytical parameters of the sensors were evaluated and compared for all tested electrodes to evaluate the properties of the planar electrode versus previously known constructions. Research has shown that the application of two membranes instead of one allows for the resistance of an electrode to be lowered and for the electrical capacitance to be elevated. Improving the electrical properties of an electrode resulted in the enhancement of its analytical properties. The pH measurement range of the planar electrode is 2-11, which is much wider in contrast to that of the single-membrane electrode. The linear range of the K+-selective planar electrode is wider than that of the coated-disc electrode and equals 10-6 to 10-1 M. The response time turned out to be a few seconds shorter, and the potential drift was smaller due to the application of an additional membrane in the electrode construction. This research creates a new opportunity to design robust potentiometric sensors, as the presented construction is universal and can be used to obtain electrodes selective to various ions.
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Kicińska A, Caba G, Barria-Parra F. Burning of municipal waste in household furnaces and the health of their owners. Sci Rep 2024; 14:32011. [PMID: 39738395 PMCID: PMC11686134 DOI: 10.1038/s41598-024-83572-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2024] [Accepted: 12/16/2024] [Indexed: 01/02/2025] Open
Abstract
The aim of the study was to determine the scale of emission and airborne dispersion of selected pollutants (PM2.5, PM10, TVOC, HCHO) associated with the combustion of various types of municipal waste (MW), its mixed stream and separate fractions, in a household furnace, as compared to conventional (CF) and alternative (AF) fuels. We demonstrated that each type of fuel (AF, CF, AFw) combusted in a household furnace is a significant source of air pollutants, especially fine PM2.5 particles, whose concentrations exceeded the limit values (3.1-17.2 times for PM2.5 and 0.5-7.4 times for PM10). The combustion of MW in household furnaces generated higher levels of PM2.5 (up to 345 µg/m3) and PM10 (up to 369 µg/m3) than AF or CF, at the same time being a significant source of TVOC (up to 0.3 mg/m3) and HCHO (0.4 mg/m3). The analysis showed that according to the Polish and European classification, air quality (AQI) during the combustion of all the materials analyzed is very poor (n = 12) or extremely poor (n = 19). The combustion of such materials as polystyrene, rubber and upholstery foam in household furnaces generates drastically high health risk to local inhabitants. We found that the combustion of polystyrene generated the highest Cancer Risk (CR) values of 1.04E-01 (children) and 2.60E-02 (adults), exceeding the acceptable level multiple times (CR > 10-6). Inhalation exposure to very poor air quality can lead to health problems, such as disorders of the respiratory, cardiovascular and immune systems. Additional risk is posed by solid fuel combustion in rural areas, which may be a significant factor deteriorating the chemical condition of soils, especially those used for agricultural purposes.
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Kwiatkowski M, Zhang G. Numerical Analysis of the Influence of Air Flow Rate on the Development of the Porous Structure of Activated Carbons Prepared from Macadamia Nut Shells. MATERIALS (BASEL, SWITZERLAND) 2024; 17:6264. [PMID: 39769863 PMCID: PMC11679797 DOI: 10.3390/ma17246264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2024] [Revised: 12/11/2024] [Accepted: 12/17/2024] [Indexed: 01/11/2025]
Abstract
This paper presents the numerical analysis of the influence of air flow rate on the porous structure development of activated carbons prepared from macadamia nut shells. The analyses based on nitrogen and carbon dioxide isotherms were carried out by the new numerical clustering-based adsorption analysis method. Therefore, it was possible to evaluate the porous structure with high precision and reliability. In particular, the results obtained showed that activated carbon prepared at an air flow rate of 700 cm3/min has the highest adsorption capacity with respect to this adsorbate, but with surface heterogeneity. On the other hand, numerical analysis based on carbon dioxide adsorption isotherms showed that the activated carbon with the highest adsorption capacity towards carbon dioxide is the sample obtained at an air flow rate of 500 cm3/min. The analyses conducted have shown that too high an air flow rate causes a violent oxidation reaction, leading to uncontrolled burning of the carbonaceous substance and destruction of the structure of the smallest micropores.
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Witkowska M, Chronowska-Przywara K, Kowalska J, Zielińska-Lipiec A. Microstructure and Texture Evolution of X85MnAl29-9 Steel During Aging. MATERIALS (BASEL, SWITZERLAND) 2024; 17:5646. [PMID: 39597469 PMCID: PMC11595358 DOI: 10.3390/ma17225646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2024] [Revised: 11/14/2024] [Accepted: 11/16/2024] [Indexed: 11/29/2024]
Abstract
The research presented in this paper is part of a larger project concerning high-manganese alloys with different chemical compositions (mainly in manganese content from 21 to 31 wt.%). The presented examination results concern the analysis of the microstructure and textures in high-manganese X85MnAl29-9 steel, an age-hardenable steel, during aging at 550 °C for various times. X85MnAl29-9 steel was first hot rolled and subsequently cold rolled up to a 30% reduction. The samples were aged after deformation at 550 °C for various times in an argon atmosphere and cooled in air. The studies include X-ray phase analysis, texture measurement and observation of the microstructure by light microscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM), as well as microhardness measurement. Research using scanning and transmission electron microscopy identified carbides in the analyzed samples. The results indicate that, when aging takes place, precipitation of κ'-carbide in an austenitic matrix and carbide κ at grain boundaries occurs. The appearance of satellites on diffraction patterns suggests that (Fe, Mn)3AlC nano-carbides are formed within the austenite matrix by a spinodal decomposition mechanism after the alloy is subjected to long-term aging, which is a key element for structure analysis in the design of safety systems. The use of shorter aging times (up to 24 h) leads to an increase in hardness caused by the precipitation of small κ'-carbide particles in the matrix. However, long aging times (100 h) lead to an increase in the precipitation of the carbide phase (κ and κ'), i.e., the steel becomes overage, which results in a decrease in hardness.
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Wons W, Kłosek-Wawrzyn E, Rzepa K. Corrosion of Porous Building Ceramics Caused by Double Sulphate Salt. MATERIALS (BASEL, SWITZERLAND) 2025; 18:1041. [PMID: 40077267 PMCID: PMC11901320 DOI: 10.3390/ma18051041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2025] [Revised: 02/17/2025] [Accepted: 02/24/2025] [Indexed: 03/14/2025]
Abstract
Porous materials are subjected to the corrosive effects of soluble salts. This corrosion, typically known as efflorescence, is primarily superficial. However, internal corrosion within the material is also frequently observed. This article presents a simulation of volumetric damage in sintered porous ceramic materials (made of clay (75 vol.%), quartz sand (10 vol.%), and sawdust (15 vol.%), fired at 950 °C), caused by the crystallization of double salts, specifically ploweite (6Na2SO4·7MgSO4·15H2O) and/or glauberite (CaSO4·Na2SO4). The exact mechanism responsible for the formation and interaction of these salts has yet to be fully comprehended. It is established that this mechanism occurs in ceramic materials containing calcium compounds and in mixtures of Na2SO4 and MgSO4 salts. Dissolved Na2SO4 acts as a substrate for the formation of glauberite, while dissolved MgSO4 participates in intermediate reactions (which are necessary for the creation of glauberite).
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Chruszcz-Lipska K, Winid B, Solecka U. Application of a Strong Base Anion Exchange Resin for the Removal of Thiophenol from Aqueous Solution. Molecules 2025; 30:525. [PMID: 39942629 PMCID: PMC11821165 DOI: 10.3390/molecules30030525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2024] [Revised: 12/20/2024] [Accepted: 01/20/2025] [Indexed: 02/16/2025] Open
Abstract
Thiophenol (synonyms: phenyl mercaptan, benzenethiol) may appear in the aquatic environment as a result of human activity. It is used as a raw material in organic synthesis in various industries for the production of dyes, pesticides, pharmaceuticals and polymers, such as polyphenylene sulfide (PPS). It may also enter water through contamination with petroleum substances (thiophenol may be present in crude oil). Due to the fact that thiophenol is toxic to living organisms, its removal from water can be a very important task. For the first time, this paper presents experimental studies of the sorption and desorption process of thiophenol on an ion exchange resin. Thiophenol sorption experiments on AmbeLite®IRA402 (Cl form) were tested at different pH levels (4, 7, and 9) and different ionic strengths of the aqueous solution. Its detection in water was carried out using UV spectroscopy. At pH 4, the thiophenol sorption process is basically independent of the ionic strength of the solution, but also the least effective. The sorption capacity of a thiophenol solution in distilled water is about 0.37-0.46 mg/g, for a solution with an ionic strength of 0.1 M 0.42 mg/g. At pH 7 and 9, the sorption of thiophenol from an aqueous solution is similar and definitely more effective. The sorption capacity of the thiophenol solution in distilled water is about 13.83-14.67 mg/g, and for a solution with an ionic strength of 0.1 M, it is 2.83-2.10 mg/g. The desorption efficiency of thiophenol from AmbeLite®IRA402 resin (washing with 4% HCl) at pH 7 is 90%, which is promising for the resin reuse process. Kinetic studies were performed and a pseudo-first-order and second-order kinetic model was fitted to the obtained experimental sorption data. In most cases, the simulation showed that the pseudo-second-order model gives a better fit, especially for the sorption of thiophenol from the solution with an ionic strength of 0.1 M. The fit of the Freundlich and Langmuir isotherm models to the experimental results indicates that the latter model provides better agreement. Analysis of the infrared spectra supported by quantum chemical calculations (DFT/PCM/B3LYP/6-31g**) confirms the experimental results observed during the sorption process. At pH 7 and 9, the thiophenol is sorbed in anionic form and-together with the ion exchange processes that occur between the dissociated thiol group and the quaternary ammonium group-an interaction between the aromatic structures of thiophenolate anions and IRA402 also takes place.
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Kłapcia A, Domalik-Pyzik P. Hydrogel Dressings as Insulin Delivery Systems for Diabetic Wounds. Front Biosci (Elite Ed) 2025; 17:26446. [PMID: 40150982 DOI: 10.31083/fbe26446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2024] [Revised: 10/29/2024] [Accepted: 11/08/2024] [Indexed: 03/29/2025]
Abstract
Diabetic wounds are one of the most common and challenging complications of diabetes. Similar to chronic wounds, diabetic wounds are difficult to treat due to prolonged inflammation, a lack of angiogenesis, abnormal differentiation of new scar tissue, and the occurrence of numerous bacterial infections. Moreover, elevated sugar levels in tissues disrupt the healing process by enhancing inflammatory reactions, disrupting signaling pathways, and leading to the production of abnormal biological structures, which contribute to improper cell differentiation. Traditional dressings, such as bandages, gauze, and semi-occlusive foams, are inadequate for diabetic wounds with high exudation; moreover, frequently changing the dressing can cause secondary irritation. Hence, innovative hydrogel dressings are being developed, which, thanks to their soft polymer matrix, provide an ideal substrate for regenerating tissue. Hydrogels also allow for the introduction and controlled release of growth factors, making them a promising solution for treating diabetic wounds. Recently, researchers have focused on insulin, a hormone secreted by the human body to lower blood sugar levels, due to its interesting characteristics, such as supporting anti-inflammatory and proangiogenic processes and stimulating cell migration and proper proliferation. This review discusses the most important aspects of diabetes and diabetic wounds and traditional and innovative treatment methods, particularly hydrogel dressings used as systems for insulin delivery in response to glucose concentration.
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Jachymczyk U, Knap P, Lalik K. Improved Intelligent Condition Monitoring with Diagnostic Indicator Selection. SENSORS (BASEL, SWITZERLAND) 2024; 25:137. [PMID: 39796927 PMCID: PMC11722992 DOI: 10.3390/s25010137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2024] [Revised: 12/18/2024] [Accepted: 12/27/2024] [Indexed: 01/13/2025]
Abstract
In this study, a predictive maintenance (PdM) system focused on feature selection for the detection and classification of simulated defects in wind turbine blades has been developed. Traditional PdM systems often rely on numerous, broadly chosen diagnostic indicators derived from vibration data, yet many of these features offer little added value and may even degrade model performance. General feature selection methods might not be suitable for PdM solutions, as information regarding observed faults is often misinterpreted or lost. To address these issues, a structured feature selection method based on correlation analysis supplemented with comprehensive visual evaluation was proposed. Unlike generic dimensionality reduction techniques, this approach preserves critical domain-specific information and avoids misinterpretation of fault indicators. By applying the proposed method, it was possible to successfully filter out redundant features, enabling simpler machine learning (ML) models to match or even surpass the performance of more complex deep learning (DL) architectures. The best results were achieved by a deep neural network trained on the full dataset, with accuracy, precision, recall, and F1 score of 97.30%, 97.23%, 97.23%, and 97.23%, respectively, while the top-performing ML model (a voting classifier trained on the reduced dataset) attained scores of 97.13%, 96.99%, 96.95%, and 96.94%. The proposed method for reducing condition indicators successfully decreased their number by approximately 3.27 times, simultaneously significantly reducing computational time of prediction, reaching up to 50% reduction for complex models. In doing so, we lowered computational demands and improved classification efficiency without compromising accuracy for ML models. Although feature reduction did not similarly benefit the metrics for DL models, these findings highlight that well-chosen, domain-relevant condition indicators can streamline data input and deliver interpretable, cost-effective PdM solutions suitable for industrial applications.
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Słowakiewicz M, Goraj W, Segit T, Wątor K, Dobrzyński D. Hydrochemical gradients driving extremophile distribution in saline and brine groundwater of southern Poland. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e70030. [PMID: 39440899 PMCID: PMC11497496 DOI: 10.1111/1758-2229.70030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2024] [Accepted: 10/07/2024] [Indexed: 10/25/2024]
Abstract
Extreme environments, such as highly saline ecosystems, are characterised by a limited presence of microbial communities capable of tolerating and thriving under these conditions. To better understand the limits of life and its chemical and microbiological drivers, highly saline and brine groundwaters of Na-Cl and Na-Ca-Cl types with notably diverse SO4 contents were sampled in water intakes and springs from sedimentary aquifers located in the Outer Carpathians and the Carpathian Foredeep basin and its basement in Poland. Chemical and microbiological methods were used to identify the composition of groundwaters, determine microbial diversity, and indicate processes controlling their distribution using multivariate statistical analyses. DNA sequencing targeting V3-V4 and V4-V5 gene regions revealed a predominance of Proteobacteriota, Methanobacteria, Methanomicrobia, and Nanoarchaea in most of the water samples, irrespective of their geological context. Despite the sample-size constraint, redundancy analysis employing a compositional approach to hydrochemical predictors identified Cl/SO4 and Cl/HCO3 ratios, and specific electrical conductivity, as key gradients shaping microbial communities, depending on the analysed gene regions. Analysis of functional groups revealed that methanogenesis, sulphate oxidation and reduction, and the nitrogen cycle define and distinguish the halotolerant communities in the samples. These communities are characterised by an inverse relationship between methanogens and sulphur-cycling microorganisms.
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Ungeheuer K, Marszalek KW, Tokarz W, Perzanowski M, Kąkol Z, Marszalek M. DFT electronic structure investigation of chromium ion-implanted cupric oxide thin films dedicated for photovoltaic absorber layers. Sci Rep 2024; 14:19830. [PMID: 39191943 PMCID: PMC11349985 DOI: 10.1038/s41598-024-70442-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2024] [Accepted: 08/16/2024] [Indexed: 08/29/2024] Open
Abstract
This study explores the enhancement of cupric oxide (CuO) thin films for photovoltaic applications through chromium doping and subsequent annealing. Thin films of CuO were deposited on silicon and glass substrates using reactive magnetron sputtering. Chromium was introduced via ion implantation, and samples were annealed to restore the crystal structure. The optical and structural properties of the films were characterized using X-ray diffraction, spectrophotometry, and spectroscopic ellipsometry. Results indicated that implantation reduced the absorbance and conductivity of the films, while annealing effectively restored these properties. Sample implanted with 10 keV energy and 1 × 1014 cm-2 dose of Cr ions, after annealing had sheet resistance of 1.1 × 106 Ω/sq compared to 1.7 × 106 Ω/sq for non implanted and annealed CuO. Study of crystalline structure confirmed the importance of annealing as it reduced the stress present in the material after deposition and implantation. Density Functional Theory (DFT) calculations were performed to investigate the electronic structure and optical properties of CuO with varying levels of chromium doping. Calculations revealed an energy gap of 1.8 eV for undoped CuO, with significant changes in optical absorption for doped samples. Energy band gap determined using absorbance measurement and Tauc plot method had value of 1.10 eV for as deposited CuO. Samples after implantation and annealing had energy band gap value increased to about 1.20 eV. The study demonstrates that chromium doping and subsequent annealing can enhance the optical and electronic properties of CuO thin films, making them more efficient for photovoltaic applications.
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Wójcik-Bania M, Stochmal E. Thermal Properties of Polysiloxane/Ag Nanocomposites with Different Network Structures and Distributions of Si-H Groups. MATERIALS (BASEL, SWITZERLAND) 2024; 17:5809. [PMID: 39685244 DOI: 10.3390/ma17235809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2024] [Revised: 11/22/2024] [Accepted: 11/25/2024] [Indexed: 12/18/2024]
Abstract
Polysiloxanes with silver nanoparticles (Ag NPs) have garnered attention for their distinctive physicochemical properties, which make them promising candidates for advanced material applications. This study presents a systematic investigation into the thermal properties and degradation mechanisms of polysiloxane/Ag nanocomposites, emphasising the innovative incorporation of Ag NPs directly into polysiloxane networks via in situ reduction of Ag⁺ ions by Si-H groups. Six polysiloxane matrices were synthesised by hydrosilylation of poly(methylhydrosiloxane) (PMHS) or poly(vinylsiloxane) (polymer V3) with three cross-linking agents of varying molecular structures and functionality. Thermogravimetric analysis combined with mass spectrometry revealed that the introduction of Ag NPs alters the thermal properties of polysiloxane networks, primarily affecting the redistribution of Si bonds that occurs during the pyrolysis of these systems. Monitoring the pyrolysis process using FTIR spectroscopy allowed us to investigate the effect of the presence of Ag NPs on the degradation mechanism of the studied nanocomposites. The presence of the free-carbon phase and metallic silver phase in the Ag-containing silicon oxycarbide materials obtained was confirmed by Raman spectroscopy and XRD analyses, respectively. These findings demonstrate the possibility of fabricating Ag/SiOC materials with ceramic residues in the range of 43 to 84%. This work provides new insights into the thermal behaviour of polysiloxane/Ag nanocomposites and underscores their potential for high-performance applications in thermally demanding environments.
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Muthu C, Resmi AN, Ajayakumar A, Ravindran NEA, Dayal G, Jinesh KB, Szaciłowski K, Vijayakumar C. Self-Assembly of Delta-Formamidinium Lead Iodide Nanoparticles to Nanorods: Study of Memristor Properties and Resistive Switching Mechanism. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2304787. [PMID: 38243886 DOI: 10.1002/smll.202304787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 12/02/2023] [Indexed: 01/22/2024]
Abstract
In the quest for advanced memristor technologies, this study introduces the synthesis of delta-formamidinium lead iodide (δ-FAPbI3) nanoparticles (NPs) and their self-assembly into nanorods (NRs). The formation of these NRs is facilitated by iodide vacancies, promoting the fusion of individual NPs at higher concentrations. Notably, these NRs exhibit robust stability under ambient conditions, a distinctive advantage attributed to the presence of capping ligands and a crystal lattice structured around face-sharing octahedra. When employed as the active layer in resistive random-access memory devices, these NRs demonstrate exceptional bipolar switching properties. A remarkable on/off ratio (105) is achieved, surpassing the performances of previously reported low-dimensional perovskite derivatives and α-FAPbI3 NP-based devices. This enhanced performance is attributed to the low off-state current owing to the reduced number of halide vacancies, intrinsic low dimensionality, and the parallel alignment of NRs on the FTO substrate. This study not only provides significant insights into the development of superior materials for memristor applications but also opens new avenues for exploring low-dimensional perovskite derivatives in advanced electronic devices.
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Łucarz M, Dereń M. Thermal Regeneration of Spent Sand with Furfuryl Binder from an Ecological and Economic Point of View. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7102. [PMID: 38005032 PMCID: PMC10672303 DOI: 10.3390/ma16227102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/29/2023] [Accepted: 11/07/2023] [Indexed: 11/26/2023]
Abstract
The recovery of the grain matrix from spent moulding sand is a constant challenge in making the best possible use of the deposits of quartz sand material, as well as in protecting them. In the case of spent sand with organic binders, the best method to recover the grain matrix is thermal regeneration. However, this method is expensive and requires adequate attention to the emission of harmful compounds into the atmosphere. This paper presents a new concept for implementing the thermal regeneration process. A suitable regeneration temperature was adopted for the furfuryl binder moulding sand, and a change in the design of the device was introduced in the area of the utilisation of gases generated during the combustion of the spent binder. To confirm the assumptions made, and to assess the appropriate suitability of the material recovered, the technological parameters of the material obtained were verified, namely, ignition losses, sieve analysis, bending strength, and pH value. The consumption of media for the process was also analysed from an economic point of view, as well as the emission of BTEX (a mixture of volatile aromatic hydrocarbons-benzene, toluene and three isomers of xylene) gases under different conditions of the process. On the basis of the research conducted, it was concluded that lowering the regeneration temperature of regeneration does not adversely affect the technological parameters of the moulding sand on the regenerate matrix. Changing the design of the regenerator does not result in increased emissions of harmful substances to the environment. Studies indicate that the appropriate setting of thermal regeneration parameters and the optimal design of the employed equipment are favourable factors in reducing the cost of the process while not compromising the quality of the moulding sand and the environmental impact.
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Biessikirski A, Kaczmarczyk GP, Kuterasiński Ł, Machowski G, Stopkowicz A, Ruggiero-Mikołajczyk M. Analysis of Wall Thickness and Absorption Characteristics of Ammonium Nitrate(V) from Various Sources. MATERIALS (BASEL, SWITZERLAND) 2024; 17:4618. [PMID: 39336359 PMCID: PMC11433477 DOI: 10.3390/ma17184618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2024] [Revised: 09/17/2024] [Accepted: 09/19/2024] [Indexed: 09/30/2024]
Abstract
This study investigates the wall thickness and specific surface area (SBET) of ammonium nitrate(V) samples of varying provenance. The research focuses on both fertilizer-grade ammonium nitrate(V) and three porous prill samples obtained from different manufacturers. The samples were analyzed using tomography scanning and two distinct porosimetry methods. The wall thickness analysis revealed that fertilizer-grade ammonium nitrate(V) possesses thicker walls, ranging from 0.05 to 0.40 mm, compared to porous prill-type ammonium nitrate(V), which predominantly exhibited wall thicknesses between 0.05 and 0.025 mm, with occasional thicker regions up to 0.040 mm. These variations in wall thickness are likely attributable to differences in manufacturing processes and prilling conditions specific to the ammonium nitrate(V) porous prill-type samples. The specific surface area (SBET), derived from nitrogen adsorption measurements, indicated that the samples exhibited surface areas ranging from 0.011 to 0.466 m2·g, suggesting that these samples do not exhibit particularly high absorption capacities. However, the SBET values obtained from the mercury intrusion method suggested significantly higher absorption capacities, falling within the range of 4.87-18.29 m2·g. These findings suggest that mercury porosimetry may provide a more accurate assessment of the porosity and absorption potential of ammonium nitrate(V) samples.
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Ksiazek M, Boron L. Microstructure, Tribological, and Corrosion Behavior of HVOF-Sprayed (Cr 3C 2-NiCr+Ni) Coatings on Ductile Cast Iron. MATERIALS (BASEL, SWITZERLAND) 2025; 18:1856. [PMID: 40333552 PMCID: PMC12029035 DOI: 10.3390/ma18081856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2025] [Revised: 04/09/2025] [Accepted: 04/10/2025] [Indexed: 05/09/2025]
Abstract
The HVOF (High Velocity Oxy-Fuel) thermal spraying method is widely used in surface engineering to produce coatings with high hardness, low porosity, and excellent crack resistance. Composite coatings with chromium carbide (Cr3C2) in a nickel-chromium (NiCr) matrix are commonly applied in demanding environments, such as the energy and transport sectors. This study compares the microstructure, mechanical, tribological, and corrosion properties of two coatings-Cr3C2-25(Ni20Cr)-10(Ni) and Cr3C2-25(Ni20Cr)-deposited on ductile cast iron using HVOF. The addition of 10 wt.% Ni enhances coating integrity, mechanical performance, and environmental resistance by improving ductility, reducing residual stress, enhancing wettability, and balancing hardness with improved crack, wear, and corrosion resistance. Microstructure analysis via LM (Light Microscopy) and SEM (Scanning Electron Microscopy), along with chemical and phase characterization using EDS (Energy Dispersive X-ray Spectroscopy) and XRD (X-ray Diffraction), revealed that the Ni-enriched Cr3C2-25(Ni20Cr)-10(Ni) coating exhibited a denser structure, lower porosity, and high hardness. Its microstructure consists of large, partially melted Ni particles and fine Cr3C2 and Cr7C3 carbides embedded in the NiCr matrix, some at submicron scales. Performance tests, including indentation (HIT, EIT, KIC), scratch, and corrosion resistance assessments, confirmed that Ni addition improves crack resistance, wear durability, and corrosion protection. Consequently, these coatings demonstrate superior operational durability, making them more effective in challenging environments.
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Kurpiel S, Zagórski K, Cieślik J, Skrzypkowski K, Tuleshov A. Evaluation of the Surface Topography and Deformation of Vertical Thin-Wall Milled Samples from the Nickel Alloy Inconel 625. MATERIALS (BASEL, SWITZERLAND) 2024; 17:295. [PMID: 38255463 PMCID: PMC10820099 DOI: 10.3390/ma17020295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 12/30/2023] [Accepted: 01/05/2024] [Indexed: 01/24/2024]
Abstract
During the production of components, manufacturers of structures are obliged to meet certain requirements and ensure appropriate quality characteristics. It is especially important during the manufacturing of thin-walled structures, which are subject to many errors during machining due to the reduced rigidity of the products, including the deformation of thin walls, which may be the result of the vibration of the system. The appearance of vibrations reduces the quality of the machined surface affecting the increase in the values of surface topography parameters-waviness and roughness. Thin-wall structures-titanium or nickel alloy, among others-play a key role in the aerospace industry, which constantly strives to reduce the weight of the entire structure while meeting requirements. The present work focuses on the evaluation of the parameters of surface topography, dimensional and shape accuracy during the milling of nickel alloy Inconel 625 samples containing a thin wall in a vertical orientation. The experiment was conducted under controlled cutting conditions using a constant material removal rate. As part of the surface topography section, the distribution of waviness, Wa and Wz, and roughness, Ra and Rz, was determined in selected measurement areas in the direction parallel to the direction of the feed motion. Dimensional deviations, measured with a 3D optical scanner, were determined in selected cross sections in the direction perpendicular and parallel to the bottom of the sample presenting the deflection of the thin-walled structure. The results provide information that the used parameter sets affect the measured quantities to varying degrees.
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