Sample S2 Research Articles

3D Printing of Virucidal Polymer Nanocomposites (PLA/Copper Nanoparticles)

Metallic nanoparticles with virucidal properties dispersed in a polymeric matrix have gained prominence in the scientific community as a rapid and effective alternative that employs the additive manufacturing (AM) or 3D printing method. This study aims to produce filaments for 3D printing using polymer nanocomposites based on polylactic acid (PLA) and copper nanoparticles (CuNPs) in different proportions. The virucidal activity of various proportions of nanoparticles in PLA was investigated. The composites were produced following a mixture design (DOE) with concentrations ranging from 1% to 2% copper nanoparticles, which were blended with PLA using a single-screw extruder. The samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength testing, and fracture analysis using scanning electron microscopy (SEM). A thermal analysis of the composites indicated that the CuNPs contributed to an increase in the degradation temperature and crystallization of the PLA. Sample S7 (1.25% of CuNPs) exhibited a 4% increase in the degradation temperature compared to pure PLA. The best tensile strength results were observed in sample S7 (1.25% of CuNPs), 30% more than sample S3 (1.33% of CuNPs) due to good material cohesion, as evidenced by microscopy analyses. Regarding virucidal analyses, most composites demonstrated virus inhibition activity.

An In Vitro Study of the Effects of Methotrexate Loaded Biocomposite Beads on MG63 Osteoblast Cells

This study aims to synthesize a new localized drug delivery system of bioglass, polyvinyl alcohol (PVA), cellulose (CNC), and sodium alginate (SA) beads as a carrier for methotrexate (MTX) drugs for the treatment of osteosarcoma. Methotrexate /Bioglass-loaded Polyvinyl/Cellulose/Sodium alginate biocomposite beads were prepared via the dropwise method with different concentrations of (65%SiO2-30%CaO- 5%P2O5) bioglass. Samples were named B0, S0, S1, S2, and S3, respectively. Calcium chloride (CaCl2) was used as a cross-linking agent. The obtained biocomposite beads were investigated by different techniques FTIR, XRD, SEM, etc. The bioactivity of MTX/BG-loaded PVA-CNC-SA biocomposite beads was tested by immersion in simulated body fluid (SBF). The profile release of methotrexate was investigated with UV–vis spectroscopy for 30 days. A cytotoxicity study of the methotrexate was performed by a human osteosarcoma (MG-63) cell line. Results indicated that the formation of a hydroxyapatite layer on the bead’s surface confirmed its biological activity. Bioactivity was directly proportional to the BG content. All samples of B1, S0, S1, S2, and S3 exhibited significant maximum release up to 6 days and were controlled gradually. Cytotoxicity results of biocomposite beads showed that high cell death was detected on the MG-63 cells, with (IC-50 ± SD) of S3 (116.16 ± 1.57) compared with B1 (306.99 ± 2.72) and S1 (204.74 ± 4.55) due to the high release of MTX, which was confirmed by the results of the drug release profile. Results prove that the prepared biocomposite beads can be used as bioactive, drug delivery systems, and anticancer materials.

Enhanced lithium-ion battery performance with a novel composite anode: S-doped graphene oxide, polypyrrole, and fumed silica

In this work, a novel composite anode material was developed, utilizing S-doped graphene oxide (SGO), polypyrrole (PPy), and fumed silica to enhance the performance of lithium-ion batteries (LIBs). The chronoamperometric approach was used to produce SGO, while the chemical method was employed to synthesize PPy. A composite of SGO, PPy, and fumed silica was prepared as an anode for a half-cell, using two samples: one with a high PPy ratio (S1) and the other with a low PPy ratio (S2) and compared the results with bare sample (S0). The S1 sample exhibited a good initial discharge capacity (648 mAh g-1), with capacities of 207 and 131 mAh g-1at 5 C and 10 C, respectively. S1 and S2 also demonstrated superior cycling stability at a high current (100 cycles at 10 C), with a retention capacity of 99 and 87%, respectively compared with S0 which retained only 68%. Coin-type full cells with S1 as the anode and LiFePO4(LFP) as the cathode were assembled and compared with commercial graphite anodes. The S1 full cell showed a high reversible capacity (164 mAh g-1at 0.1 C), with a capacity retention of 66% after 100 cycles at 10 C. At the same time, the graphite anode exhibited a reversible capacity of 133 mAh g-1at 0.1 C, with a capacity retention of 58% after 100 cycles at 10 C. The S1 full cell achieved a gravimetric energy density of 164 W h kg-1at 0.1 C and 49 W h kg-1at 10 C, which is 25% greater than that of the graphite full cell(39 W h kg-1) at 10 C. These distinguishing characteristics of S1 make it a viable substitute for graphite as a high-performance anode material in LIBs, opening the possibility for devices with reliable battery systems.

Physicochemical Properties, Antioxidant Activity, and Flavor Profile of Strawberry Fruit-Based Novel Drinking Jelly Made with Gracilaria fisheri Seaweed as a Gelling Agent at Varying Concentrations.

Gracilaria fisheri (GF) is a red seaweed that is widely found in Southeast Asia and has gained attention for its potential bioactive compounds and versatile applications in food products. This study explored the potential of GF as a natural gelling agent in the development of sustainable strawberry-based drinking jelly. By utilizing GF at varying concentrations (0.2 (S1), 0.4 (S2), 0.6 (S3), 0.8 (S4), and 1.0% (S5)), the impact on the physicochemical, textural, phytochemical, and flavor profiles of the strawberry concentrate-based drinking jelly was examined. The results demonstrated that GF concentration significantly affected the color characteristics, structural development, and flavor profiles of the drinking jelly samples. Increasing GF levels progressively enhanced the lightness (L*) and redness (a*) values while reducing the yellowness (b*), with optimal visual appeal achieved in the S4 samples compared to others. Microscopical observations revealed that gel matrix development improved with GF concentrations up to 0.8% (S4), transitioning from a sparse, liquid-like structure at lower levels to a compact, over-gelated network at 1.0% (S5). Physicochemical parameters, including pH, total soluble solid (TSS), and TSS/titratable acidity (TA) ratios, increased with GF levels, contributing to a sweeter, less acidic product, while water activity (aw) decreased, enhancing jelly stability. Viscosity and sulfate content increased significantly with GF concentration, indicating improved gel strength but reduced fluidity. Phytochemical analysis revealed that ascorbic acid (AsA) and total phenolic content (TPC) decreased progressively with higher GF levels, leading to a reduction in antioxidant activity (DPPH and ABTS). Volatile compound analysis identified alcohols, esters, and aldehydes as dominant contributors to the flavor profile. 1-Octanol (waxy, citrus-like) and methyl anthranilate (grape-like, sweet) increased substantially, while minor groups such as terpenoids and phenolic compounds contributed floral and woody notes. The findings suggest that S4 samples strike the optimal balance between texture, color, flavor, and antioxidant properties, achieving a cohesive, visually appealing, and flavorful drinking jelly suitable for commercial applications.

Effect of bismuth oxide on the gamma-ray shielding properties of phosphate glass P2O5-Bi2O3-Na2SO4-ZnO in the energy range (0.1–3 MeV)

In this paper, the gamma radiation attenuation parameters were calculated using Phy-X/PSD for a prepared quaternary system of phosphate glass (95-x)P2O5-xBi2O3-3Na2SO4-2ZnO, where (x = 30, 40, and 50 mol%). In addition, the attenuation interactions were calculated using the X-Com program, as all these calculations were done in the range of energies (0.1–3 MeV). The results showed that the S3 sample had the highest value of the mass attenuation coefficient up to the energy value of 0.8261 MeV, after which the values of the three investigated samples were approximately equal. The S3 sample also has the lowest value for a half value layer during the measured range of energy. The results also showed that the photoelectric effect interaction is the largest contributor to the attenuation process at the first three energies (0.1, 0.15, and 0.2 MeV), and at energy values ​​with 0.3–3 MeV, the Compton effect becomes the largest contributor to the attenuation process. The contribution of the pair production effect interaction begins to appear at the energy 1.025 MeV, and its contribution to the gamma ray attenuation process increases gradually in association with the Compton effect interaction until the value of 3 MeV.

Prevalence of plant parasitic nematodes in irrigation water and soil in clove and tomato greenhouses in Isparta Province of Türkiye

The study was carried out to determine the contamination status of irrigation water with plant parasitic nematodes and the effect of their spread in the greenhouse soil. For this purpose, soil samples and water samples from the irrigation source of the greenhouse were taken from the same greenhouses in May and October in Isparta Province of Türkiye. A total of 20 samplings were collected from 13 tomato and 7 clove greenhouses. The irrigation sources of these greenhouses were notedas 8 wells and 12 open pools. Nematode densities in 100 g of soil and 1 l of water were determined. In the study, 8 economically important plant parasitic nematode genera (Meloidogyne spp., Criconemoides spp., Helicotylenchus spp., Ditylenchus spp., Pratylenchus spp., Paratylenchus spp., Xiphinema spp. and Tylenchus spp.) were detected in irrigation water and soil samples. The percentages of presence of Criconemoides spp., Helicotylenchus spp., Ditylenchus spp., Pratylenchus spp., Paratylenchus spp., Xiphinema spp. and Tylenchus spp. in soil were found to be 15%, 35%, 25%, 45%, 25%, 25% and 45%, respectively. The percentages of their presence in water samples were determined as 25%, 35%, 35%, 25%, 25%, 30% and 30%, respectively. In seven soil samples (S1, S6, S7, S13, S17, S20) Meloidogyne spp. has been found. Five of these samples (S6, S7, S12, S17, S20) belong to tomato greenhouses irrigated with pool water. While the S13 sample belongs to the clove greenhouse soil irrigated with pool water, the S1 sample was taken from the tomato greenhouse irrigated with well water. Meloidogyne spp. were in both soil and water samples of S1, S6, S7, S12, S13, S17 and S20. While S9 and S18 were only found in water samples. It appears that the likelihood of root knot nematodes being present is higher in greenhouses irrigated from open pools. In general, nematode densities were found to be higher in soil and water samples in October. While Meloidogyne spp. densities varied between 100-900 individuals/100 g of soil, they varied between 200-1400 individuals/1 L of water samples. In the study, significant evidence was obtained regarding the transmission of plant parasitic nematodes to greenhouse soil through irrigation water.

The Effect of Infiltration Temperature on the Microstructure and Magnetic Levitation Force of Single-Domain YBa2Cu3O7-x Bulk Superconductors Grown by a Modified Y+011 IG Method.

During the preparation of single-domain (S-D) REBa2Cu3O7-x (RE-123) superconducting bulks, the seed crystals can serve as templates for crystal growth, guiding the newly formed crystals to grow in a specific direction, thereby ensuring the consistency of the crystal orientation within the sample. However, the infiltration temperature is typically restricted to approximately 1050 °C when employing NdBa2Cu3O7-x (Nd-123) crystal seeds in the traditional top-seeded infiltration growth (TSIG) technique for producing single-domain Y-123 bulk superconductors. In the present study, to overcome the temperature limitations of the heat treatment process, the optimized Y2O3 +011 IG (011 refers to BaCuO2 powder) method was employed to fabricate a group of single-domain Y-123 bulks with a high-temperature infiltration (1000-1300 °C). The reason for the differences in the superconducting properties between the different samples was analyzed by studying the relationship between the microstructure of the infiltrated pellet and the final Y-123 sample. The research findings were as follows: (1) when the infiltration temperature exceeded 1150 °C, the successful preparation of single-domain YBa2Cu3O7-x (Y-123) bulks became unattainable due to the coarsening or melting decomposition of the Y2BaCuO5 (Y-211) phase according to the SEM-EDS analysis; (2) the content of the Y-211 phase within the Y-123 matrix was approximately 40.8%, 37.2%, 32.7%, 30.5%, and 46.4% for the different final samples; (3) with an increasing infiltration temperature, the magnetic levitation forces exhibited an initial increase followed by a subsequent decline. The maximum levitation force of 47.1 N at 77 K was reached in the sample S3 infiltrated at 1100 °C.

Investigating the properties and characteristic analysis of frictionally welded dissimilar Inconel alloys

Friction welding of Inconel 625 and Inconel 825 alloys is crucial for high-performance applications like turbocharger shafts, where high tensile strength and corrosion resistance are essential. This study evaluated the key aspects of the welding process and the resulting mechanical properties of the joints. Among the samples, Sample S3—welded at a spindle speed of 2350 rpm, soft load of 700 Nm, and friction load of 1300 Nm—demonstrated the most favorable mechanical properties, with a tensile strength of 641.63 MPa, yield stress of 540.11 MPa, and elongation of 17.86%. These values align with or exceed the mechanical properties reported in similar studies on friction welding of Inconel alloys, where tensile strengths typically range between 600 and 652 MPa. Scanning electron microscopy (SEM) analysis revealed no visible cracks in Sample S3, confirming the quality and integrity of the welds. Additionally, electron backscatter diffraction (EBSD) analysis provided a deeper understanding of the microstructural characteristics, revealing a refined grain size of around 10 microns and uniform grain structure with 52.15% high-angle grain boundaries minimal anisotropy, which further contributes to the material's strength and reliability. The optimization of welding parameters has allowed the identification of ideal conditions for achieving superior mechanical properties. This study demonstrates the efficacy of the friction welding process for Inconel alloys, highlighting its potential for economically viable and sustainable applications.

Cold Plasma Treatment of Quinoa Grains: Changes in Phytic Acid, Saponin, Content, and Antioxidant Capacity.

The impact of atmospheric cold plasma (ACP) treatment (at 50 and 60 kV for 5 and 10 min) on nutritional (total phenolic and flavonoids contents, antioxidant capacity, and TBARs) and antinutritional (saponin and phytic acid) characteristics of quinoa grains has been investigated at this study. Results indicated that ACP treatment is significantly effective to reduce the antinutritional compounds compared with the control sample (p ≤ 0.05), among which S4 (i.e., treated at 60 kV for 10 min) and S2 (i.e., treated at 50 kV for 10 min) samples showed the highest decrease in saponin and phytic acid content, respectively. Also, total phenolic content and antioxidant capacity (DPPH and FRAP) of ACP-treated samples have decreased compared with the control sample. The flavonoid content of ACP-treated samples has been increased compared with the control sample (p ≤ 0.05). In general, the S4 (at 60 kV for 10 min) samples had the highest amount of flavonoid and phenolic content compared with the other samples. A significant reduction in TBAR values has been observed by ACP treatment with the maximum reduction at S4 (i.e., treated at 60 kV for 10 min) samples. Results indicated that ACP treatment at 60 KV for 10 min is effective to reduce the antinutritional compounds and maintain the antioxidant compounds of quinoa grains as well. Considering the necessity of keeping the nutritional characteristics of grains through processing, it needs to be monitored and optimized the condition in a way that nutritional characteristics are preserved.

Metagenomic Analysis Revealing the Impact of Water Contents on the Composition of Soil Microbial Communities and the Distribution of Major Ecological Functional Genes in Poyang Lake Wetland Soil.

Poyang Lake is the largest freshwater lake in China, which boasts unique hydrological conditions and rich biodiversity. In this study, metagenomics technology was used to sequence the microbial genome of soil samples S1 (sedimentary), S2 (semi-submerged), and S3 (arid) with different water content from the Poyang Lake wetland; the results indicate that the three samples have different physicochemical characteristics and their microbial community structure and functional gene distribution are also different, resulting in separate ecological functions. The abundance of typical ANME archaea Candidatus Menthanoperedens and the high abundance of mcrA in S1 mutually demonstrate prominent roles in the methane anaerobic oxidation pathway during the methane cycle. In S2, the advantageous bacterial genus Nitrospira with ammonia oxidation function is validated by a large number of nitrification functional genes (amoA, hao, nxrA), manifesting in that it plays a monumental role in nitrification in the nitrogen cycle. In S3, the dominant bacterial genus Nocardioides confirms a multitude of antibiotic resistance genes, indicating their crucial role in resistance and their emphatic research value for microbial resistance issues. The results above have preliminarily proved the role of soil microbial communities as indicators predicting wetland ecological functions, which will help to better develop plans for restoring ecological balance and addressing climate change.

TESTING FOR BACTERIAL CONTAMINATION ON CHICKEN (Gallus gallus domesticus) IN THE TRADITIONAL MARKET OF SOUTH LANGOWAN DISTRICT

Chicken meat (Gallus gallus domesticus) plays an important role in society with its role as one of the sources of fulfillment of animal protein in Indonesia. With the high consumption of chicken meat by the public, the hygiene and safety of chicken meat must be ensured so as not to incur losses to the people. This study aimed to determine the bacterial contamination based on the testing of Total Plate Counts, Coliform, Escherichia coli, and Salmonella sp. Meet the requirement of the Indonesian National Standard on chicken meat in the traditional market of Langowan Selatan District. The method used in this research is a descriptive method to analyze and describe the results of the study, the testing using several indicators to directly conclude bacterial contamination. The results of the total plate count bacterial contamination test of the colonies, TPC in sample 1 = 29,1x kol/, sample 2 = 29,4x kol/, sample 3 = 27,7x kol/. MPN of Coliform and Escherichia coli results obtained in samples S1, S2, and S3 are 11x kol/gr. The results of microbact Salmonella sp. In samples S1 are positive, and S2 and S3 are negative. Based on observations, it is suspected that contamination occurs because sellers use equipment that is less sterile and there is no cover or barrier so the chicken meat is in direct contact with the air and customer. It is concluded that based on bacterial testing indicators, chicken meat in the traditional market of Langowan Selatan District has exceeded the limit of SNI 7388 2009 and is contaminated.

Mechanical Synthesis and Calorimetric Studies of the Enthalpies of Formation of Chosen Mg-Pd Alloys.

Despite many years of research and continuous improvements in scientific equipment, some of the thermodynamic properties of binary systems are still unknown, or are only theoretically predicted or calculated. This situation often arises from the difficulties in preparing alloys for experimental measurements. The alloys from the Mg-Pd system, especially for the Pd-rich side, are difficult to produce, and the availability of thermodynamic data is very limited. Therefore, this paper presents calorimetric studies on the standard enthalpy of formation of alloys from the Mg-Pd system, which were prepared using mechanical alloying. Three alloys (S1, S2, and S3) were synthesized, homogenized, and subjected to X-ray diffraction (XRD) analysis to investigate their phase composition. The XRD studies showed that the alloys designated as S1 and S2 were the intermetallic phases Mg6Pd and Mg0.9Pd1.1, and the S3 sample was a mixture of MgPd and MgPd3 intermetallic phases. Their heat effects, measured by drop calorimetry, were used to calculate the values of the standard enthalpies of formation of the prepared phases. The values obtained were as follows: -27.5 ± 1.1 kJ/mol at. for the Mg6Pd intermetallic phase, -72.7 ± 1.0 kJ/mol at. for the Mg0.9Pd1.1 intermetallic phase, and -46.8 ± 1.5 kJ/mol at. for the alloy which was a mixture of MgPd and MgPd3. These data were compared with values from the existing literature on the enthalpy of formation of alloys, as well as with data calculated using Miedema's model.

Heavy Metal Contamination in the Kali River: Irrigation Unsuitability and its Adverse Effects on Human Health

This study evaluates the concentration of heavy metals in the Kali River, Uttar Pradesh (from Bhavanpur, Saharanpur to Pithlokhar, Meerut). Some heavy metals (HMs) (Cr 10.3-479.6 µg/l, Mn (128.3-9054.5 µg/l), Fe (0-14534 µg/l), Ni (0-789.7 µg/l), Cu (57.2-32720.1 µg/l), Zn (89.7-6487.8 µg/l), As (17.3-90 µg/l), Cd (7.8-184.7 µg/l), and Pb (57.3-1860.1 µg/l) were among the HMs that exceeded allowable limits. Few risk assessment metrics (Degree of Contamination (Cd), Hazard Quotient (HQ), Carcinogenic Risk (CR), Heavy Metal Evaluation Index (HEI), and Total Hazard Index (THI) ) were applied to check the hazardous effect. However, the S2 sampling location had the greatest HPI indices, whereas Dable village (S19) had the highest values of Cd, HEI, and THI. Health risks are more likely to affect adults and children, especially in rural locations. The pollution also seriously impairs the water’s suitability for irrigation, which affects the quality of the crops and the health of the soil. To protect agricultural and human populations, immediate regulatory actions and routine water quality monitoring are required.

Flammability and Thermoregulation Performance of Multilayer Protective Clothing Incorporated with Phase Change Materials.

Firefighters need personal protection equipment and protective clothing to be safe and protected when responding to fire incidents. At present, firefighters' suits are developed by using inherently thermal-resistant fibers but pose serious problems related to comfort. In the present research, multilayered fire-fighting fabrics were developed with different fiber blends. Multilayer fire retardant (FR) fabrics with phase change materials (PCMs) inserts were developed and compared with reference multilayer fabrics without PCM. In this context, four fabric samples were chosen to fabricate the multilayer FR fabrics. Properties of multilayer fabrics were investigated, which include physical, thermo-physiological comfort, and flame-resistant performance. The heating process of the clothing was examined using infrared (IR) thermography, differential scanning calorimetry (DSC), thermal protective testing (TPP), and steady-state (Convective and Radiant) heat resistance tests. Areal density and thickness were measured as physical parameters, and air permeability (AP), overall moisture management capacity (OMMC), and thermal conductivity were measured as thermo-physiological comfort characteristics. The inclusion of PCM improved the thermal protection as well as flame resistance significantly. Sample S1 (Nomex + PTFE + Nomex with PCM) demonstrated superior fire resistance, air permeability, and thermal protection, with a 37.3% increase in air permeability as compared to the control sample (SC) by maintaining comfort while offering high thermal resilience. The inclusion of PCM enhanced its thermal regulation, moderating heat transfer. Flame resistance tests confirmed its excellent performance, while thermo-physiological assessments highlighted a well-balanced combination of thermal conductivity and air permeability. This study will help to improve the performance of firefighter protective fabrics and provide guidelines in terms of balancing comfort and performance while designing firefighter protective clothing for different climatic conditions.

Biocompatibility Analysis of the Silver-Coated Microporous Titanium Implants Manufactured with 3D-Printing Technology.

3D-printed microporous titanium scaffolds enjoy good biointegration with the residuum's soft and bone tissues, and they promote excellent biomechanical properties in attached prostheses. Implant-associated infection, however, remains a major clinical challenge. Silver-based implant coatings can potentially reduce bacterial growth and inhibit biofilm formation, thereby reducing the risk of periprosthetic infections. In the current study, a 1-µm thick silver coating was prepared on the surface of a 3D-printed microporous titanium alloy with physical vapor deposition (PVD), with a final silver content of 1.00 ± 02 mg/cm2. Cell viability was evaluated with an MTT assay of MC3T3-E1 osteoblasts and human dermal fibroblasts cultured on the surface of the implants, and showed low cytotoxicity for cells during the 14-day follow-up period. Quantitative real-time polymerase chain reaction (RT-PCR) analysis of the relative gene expression of the extracellular matrix components (fibronectin, vitronectin, type I collagen) and cell adhesion markers (α2, α5, αV, β1 integrins) in dermal fibroblasts showed that cell adhesion was not reduced by the silver coating of the microporous implants. An RT-PCR analysis of gene expression related to osteogenic differentiation, including TGF-β1, SMAD4, osteocalcin, osteopontin, and osteonectin in MC3T3-E1 osteoblasts, demonstrated that silver coating did not reduce the osteogenic activity of cells and, to the contrary, enhanced the activity of the TGF-β signaling pathway. For representative sample S5 on day 14, the gene expression levels were 7.15 ± 0.29 (osteonectin), 6.08 ± 0.12 (osteocalcin), and 11.19 ± 0.77 (osteopontin). In conclusion, the data indicate that the silver coating of the microporous titanium implants did not reduce the biointegrative or osteoinductive properties of the titanium scaffold, a finding that argues in favor of applying this coating in designing personalized osseointegrated implants.

Nuclear radiation shielding properties of calcium aluminum barium sodium borate glass samples doped with Dy3+ ions

Nuclear technology finds extensive application across various industries, medical physics, and research institutions, spanning fields such as agriculture and food technology. Despite its benefits, the pervasive use of ionizing radiation underscores the need for effective shielding materials to mitigate associated risks. Lead and concrete, traditionally favored for their attenuation properties, pose challenges due to weight, opacity, and toxicity concerns. In this context, calcium aluminum barium sodium borate glasses doped with Dy3+ ions emerge as promising alternatives for radiation shielding. This study investigates the ionizing electromagnetic radiation (gamma and X-ray) shielding capabilities of calcium aluminum barium sodium borate glasses doped with Dy3+ ions across a range of concentrations (0.1, 0.3, 0.5, and 1.0% mol). The mass attenuation coefficients and linear attenuation coefficients of four glass samples (S1 to S4) were determined using the software (Phy-X). Additionally, parameters such as effective atomic number (Zeff), half-value layer (HVL), tenth-value layer (TVL) and mean free path (mfp) were computed to assess shielding effectiveness.The results indicate that higher Dy3+ concentrations correlate with increased attenuation effectiveness, as evidenced by elevated μ and μm values. Glass sample S4, with the highest Dy3+ concentration, demonstrated superior shielding properties, attributed to its elevated density. Notably, the study elucidates the relationship between attenuation coefficients and photon energy, highlighting the dominance of photoelectric and Compton scattering effects. Furthermore, analysis of HVL, mfp, and Zeff values reveals the nuanced interplay between glass composition and radiation attenuation. Despite variations in composition, S4 consistently exhibited optimal shielding characteristics across photon energy ranges. The investigation also examines exposure and energy absorption buildup factors, indicating that higher Dy3+ concentrations lead to lower buildup values, indicative of enhanced shielding performance.In conclusion, the study underscores the potential of Dy3+ doped calcium aluminum barium sodium borate glasses as effective radiation shielding materials, offering insights into their composition-dependent attenuation properties. These findings contribute to the development of lead-free alternatives and advance the understanding of radiation shielding mechanisms in glass matrices, with implications for diverse applications in nuclear technology and beyond.

Investigation of the tribological and mechanical properties of FeCrMoCB coating on AISI 52100 bearing steel

This study examines the mechanical and tribological properties of FeCrMoCB amorphous coatings on AISI 52100 bearing steel using laser cladding (LC). Two samples with varying LC parameters were compared to uncoated polished steel. Analytical methods included scanning electron microscopy (SEM), X-ray diffraction (XRD), microhardness testing and tribological tests via a high-frequency reciprocating rig (HFRR) tribometer under both dry and lubricated conditions, were employed. Sample S1 exhibited a microhardness five times that of uncoated steel and a 95 % reduction in wear volume loss under dry conditions. Under grease-lubricated, S1 showed a 20 % reduction in the coefficient of friction and a 93 % reduction in wear volume loss. Sample S2 also outperformed uncoated steel. These results highlight the significant benefits of FeCrMoCB coatings.

In vitro study of antibacterial and anticancer activities of biosynthesized Ag-doped ZnO nanoparticles from Anisochilus Carnosus, Nephelium Lappaceum, Calotropis Gigantea

As nanoparticles exhibit various noticeable properties, showing outstanding results in nanomedicine and environmental-related problems, especially in therapeutic systems such as drug carriers for targeting the sites, etc. In this work, Ag-doped ZnO nanoparticles were synthesized via the bio-extraction method using three different plants, namely Calotropis gigantea, Nephelium lappaceum, and Anisochilus carnosus. The obtained samples were mentioned as S1, S2, and S3, respectively, and the comparison of these samples was studied. The prepared samples were further examined for their structural, morphological, and functional group studies using XRD, TEM, SEM-EDS, BET, FTIR, FT-Raman, UV, Zeta potential, and photoluminescence spectra. The results showed that the nanoparticles were highly crystalline, with a particle size ranging between 15 and 20 nm. TEM-SEM images confirmed the hexagonal, clustered, and flowered shape of the particles, with a UV absorption peak between 350 and 390 nm. The surface area of the particles in the range of 65–77 m2 g-1 with less porosity was confirmed by BET results, and the stability of the nanoparticles was confirmed by Zeta potential. Further antibacterial and anticancer activity was investigated, in which the IC50 value for a colon [HT-29] cancer cell was found to be 44.5µg/ml (S1), 39.14µg/ml (S2), and 21.81µg/ml (S3); hence, sample S3 showed higher potential cytotoxicity than the other two samples. Thus, Ag-doped ZnO nanoparticles synthesized by Anisochilus Carnosus can be considered a strong anticancer agent compared to the other two samples.

Study on the mechanical properties and gamma/neutron radiation shielding performance of SnBi/B4C composite materials

The development of multifunctional shielding materials has become a hot research topic with the increasing requirements for radiation protection materials in terms of performance, weight and non-toxicity. In this study, non-toxic SnBi/B4C composites with different B4C contents (0, 3, 6, 9, 12 and 15 wt%) were successfully prepared by powder metallurgy, and their mass attenuation coefficients, half-value layers, mean free paths, effective atomic numbers, and 0.025 eV thermal neutron shielding performance. The results show that B4C plays a key role in regulating the mechanical properties and thermal neutron shielding properties of SnBi/B4C composites. When the B4C content was 9 wt% (S3), the integrated mechanical properties of the composites were optimal, and the yield strength, tensile strength, and microhardness were enhanced by 31 %, 32 %, and 129 %, respectively, compared with those of the samples without B4C. The radiation shielding effect is remarkable, the gamma-ray shielding performance in the energy range of 0.03–0.08 MeV is better than that of Pb. Meanwhile, the S3 sample with only 3 mm thickness can shield 99.7 % of thermal neutrons, while the shielding rate of the S0 sample without B4C is only 5.2 %. Comprehensive analyses show that the SnBi/B4C composites are superior in terms of environmental protection, mechanical properties, gamma-ray and thermal neutron shielding, with lighter weight and safer use. This finding provides a theoretical basis for the selection of efficient, non-toxic and diverse radiation shielding materials for medical and other special environments.

Effects of laser energy density on the resistance to wear and cavitation erosion of FeCrNiMnAl high entropy alloy coatings by laser cladding

FeCrNiMnAl high entropy alloy (HEA) coatings are prepared on the surface of 304 stainless steel (304 SS) by laser cladding. The effects of laser energy density on the residual stress, microstructure, nanoindentation behavior, the resistance to wear, corrosion and cavitation erosion (CE) of FeCrNiMnAl HEA coatings are studied. Experimental results shows that when the laser energy density decreases from 40 J/mm2 to 24 J/mm2, the phase composition of the FeCrNiMnAl HEA coatings remains unchanged with a single BCC solid solution and the elements are uniformly distributed without obvious segregation. The average grain size of the HEA coatings is refined from 73.5 to 41.7 μm. When the laser energy density is 28 J/mm2 for S3 sample, the coating displays good forming quality and excellent comprehensive performance. The specific wear rate is only 8.2 % that of the 304 SS substrate. In addition, S3 exhibits the highest corrosion resistance as indicated by the highest corrosion potential (Ecorr) and the lowest corrosion current density (Icorr) in 3.5 wt% NaCl solution. After 10-h CE, the mean depth erosion rate (MDER) of S3 is the lowest (1.69 ± 0.03 μm/h), which is much lower than that of 304 SS (4.96 ± 0.13 μm/h), and the pure mechanical damage plays a dominant role in CE, followed by the synergistic damage effect. The excellent CE resistance of S3 is attributed to its excellent combination of corrosion resistance, mechanical properties and the self-recovery ability of passivation film.