Energy Dispersive X-ray Spectroscopy Research Articles

Preparation of a new reusable magnetic organocatalyst to synthesis of polyhydroquinoline derivatives as cytotoxic Agents: Synthesis and biological evaluation

One of the most important ways to practice environmental stewardship is to turn waste materials into useful nanomaterials through ecological recycling. This work introduces a magnetic organocatalyst made from red mud waste, adding to the “greening” of global chemical processes.The new composite (Fe3O4@SiO2@(CH2)3@4-(2-Aminoethyl)-morpholine) is introduced and characterized by different spectroscopic methods such as fourier transform infrared (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), mapping, thermogravimetric analysis (TGA) and vibrating-sample magnetometers (VSM). Catalytic activity of the catalyst was evaluated in production of some polyhydroquinoline derivatives and the results showed efficiency. Nine polyhydroquinoline derivatives were synthesized (M1-M9) and their cytotoxic properties evaluated against two human-cancerous cell lines (Hep-G2 and SW480) by MTT assay. Most of the compounds exhibited high inhibitory activity against two studied cell lines. M2 bearing 2-chloro substitution on phenyl ring was exhibited appropriate activity (IC50 = 14.70 ± 3.11 µM) against SW480 cell line in comparison to cisplatin as positive control.

Effect of substrate temperature on the performance of Sb2Se3 thin film solar cells fabricated by chemical-molecular beam deposition method

Antimony triselenide (Sb2Se3) stands as a promising candidate for photovoltaic (PV) applications due to its favorable material- and optoelectronic properties. However, the realization of further advancements in device efficiency is hindered by the substantial deficit in open-circuit voltage (VOC) attributed to the presence of multiple defect states and detrimental recombination losses.In this work, solar cells based on Sb2Se3 absorber layers deposited by chemical-molecular beam deposition method at substrate temperatures of 400 °C, 450 °C, and 500 °C. Due to the precise control of the Sb/Se ratio, Sb2Se3 thin films with stoichiometric composition were obtained, which was confirmed by energy-dispersive X-ray spectroscopy. The effect of substrate temperature on the morphology and electrical properties of Sb2Se3 thin-films were characterized by scanning electron microscopy and hot probe method. The PV performance of Mo/Sb2Se3/ZnCdS/CdS/ZnO/ITO/Au devices were investigated by current-voltage characteristics, and external quantum efficiency. The conductivity values tend to increase from 1.2 × 10–6 to 4.6 × 10–4 (Ω cm)-1 as the substrate temperature increased. Whereas, the trap-state density was determined between 7.3 × 1013 – 1.7 × 1014 cm-3 in the absorber layer by the space charge limited current method. Ultimatety, it has been shown that defect densities in Sb2Se3 films can be suppressed to some extent by optimizing the substrate temperature. Best solar cell performance of 5.36%, resulting from VOC of 476 mV, short-circuit current densit of 22.97 mA/cm−2, and fill factor of 49% at the substrate temperature of 450 °C.

Evaluation of 14-(p-tolyl)-14H-dibenzo[a,j]xanthene as a Highly Efficient Organic Corrosion Inhibitor for Mild Steel in 1 M HCl: Electrochemical, Theoretical, and Surface Characterization

Corrosion of mild steel, particularly in acidic environments such as hydrochloric acid (HCl), remains a critical issue due to its impact on material durability, economic costs, and safety concerns. This study introduces 14-(p-tolyl)-14H-dibenzo[a,j]xanthene (ZM5), a novel and highly effective organic corrosion inhibitor, to mitigate this challenge. Employing advanced electrochemical techniques: electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP), we evaluated ZM5’s performance in a 1M HCl solution, revealing an impressive inhibition efficiency of 94.7%. Surface characterization using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) further confirmed the formation of a robust protective film on the steel surface, shedding light on ZM5’s adsorption mechanisms. Complementing the experimental findings, Density Functional Theory (DFT) simulations provided theoretical insights into the anti-corrosion mechanism of ZM5, aligning well with observed results. These findings underscore ZM5's potential as a highly promising corrosion inhibitor for industrial applications, effectively enhancing the corrosion resistance of mild steel in aggressive environments.

Recovery of Bis(2-hydroxyethyl) terephthalate and terephthalic acid from waste PET bottles for synthesis of cerium-based metal-organic frameworks: A study towards supercapacitor applications

Controlled chemical recycling of plastic waste is a most important concern to reduce plastic waste as well as effective recovery of the various byproducts without toxic emission. In this study, we focused on effective recovery of Bis-2-hydroxyethylene terephthalate (r-BHET) from polyethylene terephthalate (PET) waste via solvent free melt depolymerization process. Recovered BHET was converted into terephthalic acid (r-TPA) by hydrolysis. Both r-BHET and r-TPA were used to construct a metal organic framework (MOF) with cerium metal for potential energy applications. Extensive characterization, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Field Emission Scanning Electron Microscopy (FE-SEM), and Energy-Dispersive X-ray Spectroscopy (EDX) were confirmed the structural integrity and purity of the r-BHET and r-TPA and provides insights into the well-defined structure and elemental composition of the MOFs. The specific capacitances of BHET and TPA-Ce-MOF were found to be 91.5 and 220.1 F/g respectively. Comprehensive characterization ensures the quality of the recovered products and synthesized MOFs, promoting environmentally conscious strategies in materials synthesis and energy storage applications.

The effect of cryogenic treatment on a high Co bearing DIN 1.2888 steel used as die in hot forging process

Abstract Hot work steels used as dies in metal forming processes must endure harsh conditions, typically achieved through a martensitic structure. However, retained austenite can persist after martensitic transformation, negatively impacting mechanical properties. Cryogenic treatment (CT) refines martensite, reduces retained austenite, and increases fine carbide density, thus enhancing performance. DIN 1.2888, a hot work tool steel with high cobalt content (~10%) and low carbon content (~0.2%), is less studied concerning the effects of CT. The objective of this study was to investigate how cryogenic treatment affects the mechanical and microstructural properties of DIN 1.2888 steel. Samples underwent conventional heat treatment (HT) and CT at -100, -140, and -180°C for 6 hours, followed by double tempering. Various analytical methods, including X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and Vickers Microhardness tests, were used to examine the samples. Wear mechanisms were evaluated through pin-on-disc tests under different loads, and impact toughness was measured both at room temperature and the working temperature of dies (350°C). Results indicated that lowering the cryogenic treatment temperature resulted in a slight increase in hardness values from 507HV for the heat-treated sample to 529HV for the sample treated at -180°C. Additionally, the impact toughness improved significantly, with values rising from 12.35J for the heat-treated sample to 23.44J at 350°C for the cryogenically treated sample at -180°C. Wear rates also decreased by approximately 50%, particularly at higher cryogenic treatment temperatures. The improvement in wear resistance was attributed to finer carbide precipitation and a more homogeneous distribution of carbides. These findings suggest that deep cryogenic treatment has a positive effect on DIN 1.2888 steel by decreasing retained austenite and increasing fine carbide density, leading to enhanced mechanical properties and extending the lifespan of the steel in die applications.

Assessment of contamination levels, potential ecological and human health risks due to trace elements pollution in the vicinity of the Lolodorf uranium deposit, Southern Cameroon.

The current study assessed the contamination levels and associated ecological and health risks due to hazardous trace elements in soils from Awanda and Mvengue, located in the vicinity of the Lolodorf uranium deposit in Southern Cameroon. Qualitative and quantitative analyses of the soil samples were performed using energy-dispersive X-ray spectrometry. The results indicated that the mean concentrations of metallic and trace elements in soil samples increased in the following order: U < As < Th < Pb < Cu < Ni < Zn < Cr < Mn < Fe < Al. The average concentrations of U, As, Th, Pb, Cu, Ni, Zn, Cr, Mn, Fe, and Al ranged between 0.9-3, 2.9-3.8, 9.2-15, 13.1-20.3, 11.5-42.5, 31.1-60.7, 42.9-91.6, 94.50-170.9, 100.45-500.57, 4874.8-88340 and 226147.5-324240.0mg/kg, respectively. The contamination levels of trace elements were assessed and the human health risk of chemical elements was determined. The investigated elements' average contamination factors (CF) results showed the highest mean CF recorded for Al followed by Cr, Th, Pb, Zn, Cu, Ni, Fe, U, Mn, and As. Furthermore, the findings showed that 90% of soil samples can be classified as considerably contaminated with Al, 100%, and 60% as moderately contaminated with Cr and Th, respectively. The Geo-accumulation indices of Mn, Cr, Th, U, Ni, Zn, Cu, As, and Pb were lower than 1, suggesting low contamination levels for these elements. The ecological factors and risk indices indicated a low ecological risk in the investigated area. In terms of human health risk, ingestion was identified as the primary pathway for both carcinogenic and non-carcinogenic risks, with children found to be more exposed to both risks than adults. Al, Cr, and Fe were found to be the main contributors to non-carcinogenic health risks, while Cr and Ni were the main contributors to carcinogenic health risks.

Simple synthesis of K/P co-doped graphitic carbon nitride to enhance photocatalytic performance under simulated solar irradiation

The doping or co-doping of graphitic carbon nitride (g-C3N4) with other elements is a useful modification technique that overcomes the disadvantages of the base material and enhances its photocatalytic performance. In this study, K and P were successfully incorporated into g-C3N4 using a one-step, single-precursor (K2HPO4) synthesis method. The incorporation of K and P was confirmed using energy-dispersive X-ray spectrometry and wavelength-dispersive X-ray fluorescence spectrometry. Oxytetracycline (OTC) degradation rates were compared with and without elemental doping and with variation in the precursor content. In contrast to the low OTC degradation rate exhibited by pristine g-C3N4 (29.52 ± 0.03%), incorporating K and P into g-C3N4 greatly improved OTC degradation, with the sample produced using 100 mg of the precursor K2HPO4 (KPCN-100) achieving the highest degradation rate (99.43 ± 0.53%). The effects of the co-dopants K and P on the optical, photoelectrochemical properties, and band position of g-C3N4 were also investigated. Scavenging and N2 purging tests confirmed that reactive species, including O2•- (87.25%) and 1O2 (56.53%), played an important role in the degradation of OTC. In addition, several experimental parameters, including the presence of co-existing ions and humic acid, the pH level, the initial OTC concentration, and the photocatalyst dosage, were varied to better understand the photodegradation mechanisms at work within the KPCN-100 system. The stability of KPCN-100 and the toxicity assessment of the OTC intermediate were also conducted to evaluate their potential for environmental applications. Overall, this study demonstrates a simple synthesis method for the elemental co-doping of g-C3N4, offering an effective photocatalytic strategy that can greatly enhance the efficiency of OTC degradation.

PLA/PLGA nanocarriers fabricated by microfluidics-assisted nanoprecipitation and loaded with Rhodamine or gold can be efficiently used to track their cellular uptake and distribution

This study represents a pioneering investigation into using microfluidic technology for manufacturing PLA and PLGA nanocarriers (NCs) loaded with tracer molecules or metals through a co-precipitation protocol that involves saturating the water phase. The effects of total flow rate (TFR), flow rate ratio (FRR), surfactant amount, and polymer concentration on particle sizes and distributions were examined. The average size of PLA-NCs varied from 349 ± 175 nm to 170 ± 64 nm, with surface charges ranging from −13 to −6 mV. In contrast, PLGA-NCs had an average size between 192 ± 46 nm and 100 ± 34 nm, with surface charges from –23 mV to −53 mV. Increasing the TFR from 6 to 10 mL/min with a fixed FRR of 1:1 and reducing polymer concentrations in the organic phase from 20 to 5 mg/mL generally resulted in smaller NC sizes and distributions (monodispersed), with PLGA-NCs consistently exhibiting smaller dimensions. Under these specific conditions, Rhodamine B (Rhod) and gold (Au) were successfully loaded, achieving encapsulation efficiencies exceeding 50 %. Electron microscopy analysis confirmed that the nanocarriers exhibited a consistent spherical shape with smooth surface morphology. X-ray energy-dispersive spectroscopy (EDX) revealed a uniform distribution of gold within the polymer matrix. PLA-NCs were effectively internalized by various cell types, including human Peripheral Blood Mononuclear Cells (PBMCs), HT-29 colon cancer cells, and C6 glioma cells. Uptake occurred in a dose-dependent manner for PLA-NCs sized at 260 ± 51 nm, with only 30 % internalization at 2 mg/mL concentration after 24 to 48 h. Notably, smaller PLA-NCs with a mean size of 170 ± 64 nm achieved nearly 100 % uptake across all tested cell types after 48 h, indicating that particle size significantly influenced cellular uptake

Green Synthesis of silver nanoparticles from clematis gouriana leaf extract: Physicochemical characterization and antibacterial activity determination for treatment of blood stream infections

BackgroundThe global incidence of bloodstream infections (BSIs) is rising, necessitating the development of effective therapeutic strategies to achieve complete eradication. This study focuses on the synthesis of silver nanoparticles (AgNPs) functionalized with Clematis gouriana extract (CG) (CG-AgNPs) as a potential alternative to conventional treatments for combating BSIs caused by bacterial pathogens. MethodsAgNPs were synthesized by reducing silver nitrate (AgNO₃) using CG extract. The formation of CG-AgNPs was confirmed through UV-Vis spectroscopy, while their characterization included the determination of mean particle size and zeta potential. Elemental composition was analyzed using energy-dispersive X-ray (EDX) spectroscopy. The in vitro antibacterial efficacy of CG-AgNPs was assessed through multiple assays, including a time-kill assay, a film bioadhesion assay, and measurement of reactive oxygen species (ROS) generation. ResultsSPR (surface plasmon resonance) has been employed to validate the development of AgNPs by observing a colour shift to dark brown. The mean particle size and zeta potential of the CG-AgNPs were found to be 38 ± 2nm (PDI 0.104 ± 0.03) and -31.2 ± 1.4mV, respectively. Additionally, E-XRD results show that the prepared AgNPs comply with the silver presence. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the CG-AgNPs against Staphylococcus aureus (S. aureus) were observed to be 6.25 ± 0.8µg/mL and 13.5 ± 2.4µg/mL, respectively.Similarly, the MIC and MBC of CG-AgNPs against Escherichia coli (E. coli) were found to be 13.5 ± 1.5μg/mL and 26 ± 2.8μg/mL, respectively. CG-AgNPs also prevented biofilm formation and bacterial adhesion in a dose-dependent manner; 100% inhibition was achieved in 48h at MBC. In addition, CG-AgNPs remarkably escalated the ROS level within cells, indicating their mechanism of antimicarobial activity. ConclusionsThe findings of this study demonstrate that CG-AgNPs synthesized via green synthesis exhibit significant antibacterial activity, highlighting their potential as an effective alternative for the treatment of BSIs. However, further in vivo studies are required to optimize a suitable dosage form and validate their therapeutic efficacy against bacterial infections in clinical settings.

Visible light degradation of antibiotics catalyzed by nanoporous carbon/V2O5 nanocomposite: structural, optical and electrochemical properties

In this study, nanoporous carbon (NPC) decorated V2O5 (NPC/V2O5) nanocomposite synthesized by a hydrothermal technique using biomass-derived NPC nanoflakes towards the application of berberine hydrochloride (BH) dye degradation under visible light irradiation. The prepared samples were characterized by X-ray Diffraction (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray (EDX), UV-Visible and Photoluminescence (PL) spectroscopy. Charge transfer resistance was measured by electrochemical impedance spectroscopy (EIS) and liner sweep voltammetry (LSV). XRD studies confirm the orthorhombic crystal structure of NPC/V2O5 nanocomposite. FE-SEM and TEM analysis validate their particle-like and sheet-like morphology of V2O5 and NPC respectively. Further, UV-visible DRS and PL spectra of the green synthesized NPC/V2O5 nanocomposite exhibited a low band-gap and reduced recombination rate compared to the pure counterpart which is better light-absorbing ability in the visible light region. Batch experiments represent the incorporation of NPC and V2O5 would lead to an increase the photocatalytic performance of NPC/V2O5 toward BH dye degradation. During the photocatalytic reaction, the NPC/V2O5 nanocomposite degraded rate around 97.7% against BH dye within 80 min while pure V2O5 degraded 92.5% of BH dye under same visible light irradiation time. Finally, the cyclic stability experiment exhibits the photocatalyst even stable after five consecutive tests.

Synergistic effects of liquid phase sintering and B-site substitution to enhance proton conductivity of BaZr0.1Ce0.7Y0.1Yb0.1O3-δ for protonic ceramic fuel cell

This paper is dedicated to improving the sintering and conductivity of BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) by adding ZnO-CuO dual-sintering aids. The synergistic effects of liquid-sintering of Zn and B-site substitution of Cu on the sinterability and proton conductivity of BZCYYb are systematically investigated. X-ray diffraction (XRD) analysis of BZCYYb after addition of ZnO-CuO (BZCYYb-Zn-Cu) confirms the complete perovskite phase formation without any secondary phase. The substitution of Ce4+ (0.87 Å) with Zn2+ (0.74 Å) or Cu2+ (0.73 Å) induces a shift in XRD diffraction peak to higher angle due to a decrease in lattice constant. Energy dispersive X-ray spectroscopy analysis indicate a distinct distribution of Zn primarily at the grain boundaries, while Cu is predominantly located within the grains of BZCYYb-Zn-Cu. The addition of ZnO-CuO into BZCYYb results in a denser microstructure with larger average grain size. Furthermore, the substitution of Ce4+ by Cu2+ increases the concentration of oxygen vacancies and reduces activation energy. For BZCYYb-Zn-Cu, the proton conductivity reaches 4.52×10-2 S/cm at 750 °C, approximately 3 times higher than that of BZCYYb. This enhancement can be attributed to the synergistic effects of larger average grain size resulting from liquid phase sintering of Zn, low active energy, and high concentration of oxygen vacancies arising from Cu B-site substitution. BZCYYb-Zn-Cu is used as the electrolyte for anode support SOFC, and the single cell exhibits remarkable electrochemical performance and excellent stability in H2 fuel. This research establishes a crucial theoretical foundation for the preparation and performance evaluation for large-size protonic ceramic cell.

Area-based composition predictions of materials fabricated using simultaneous wire-powder-directed energy deposition

Functionally graded materials are an emergent method for designing components with programmable site-specific material properties. These materials are typically fabricated using metal additive manufacturing tools by simultaneously feeding multiple wire and/or powder feedstocks at various rates to achieve spatial composition change. The wire-powder-directed energy deposition (WP-DED) technique is of particular interest for many functionally graded material applications by balancing the low raw materials cost of wire with the high resolution of powder. However, feeding wire and powder are inherently different processes since all extruded wire enters the melt pool, while much of the blown powder is scattered, which makes determining the composition of the build challenging. In this study, we devise a simple area-based measurement method for estimating the composition of WP-DED structures. WP-DED single beads are printed using 309L stainless steel wire and commercially pure Fe powder at five wire feed rates (0.5, 0.75, 1.00, 1.25, 1.50 mm/mm) and five powder feed rates (2, 4, 6, 8, 10 rpm). Characteristic defects including interface gaps and macrosegregation (lack of mixing) tendencies are examined. High powder feed rates (8, 10 rpm) result in interface gaps at all wire feed rates, but smooth deposition and complete mixing is achieved at low powder feed rates, particularly with lower wire feed rates as well. The area-based composition measurement method is within ±20% of energy dispersive x-ray spectroscopy measurements for all samples, showing its effectiveness as a rapid composition estimate for WP-DED materials development.

Morphology and structural properties of Sb2(SxSe1-x)3 thin film absorbers for solar cells

Using the thermal evaporation method, thin crystalline films of Sb2(Sx Se1-x)3 are produced at the substrate temperature of 300℃. The mixed powders of the Sb2S3 and Sb2Se3 is used as a source material. The influence of the S/Se component ratio on the morphology and structural characteristics of Sb2(SxSe1-x)3 thin films is investigated. As demonstrated by the results of X-ray energy dispersive spectroscopy, the formed films of Sb2(SxSe1-x)3 have a components ratio close to the stoichiometry. Besides, Morphological and structural analyses reveal significant differences in the surface morphology of Sb2(SxSe1-x)3 thin film absorbers, indicating that the properties of the films vary as a function of the S/Se composition ratio.

Enhancing wear resistance of CoNiCrMo medium entropy alloy through cold working and aging: Tradeoffs with corrosion performance

This study investigates the wear behavior and corrosion resistance of MP35 N alloy under various conditions, including annealed, cold-worked, and aged states. The microstructure was characterized using optical microscopy, X-ray diffraction, and transmission electron microscopy. Results indicated that cold rolling induced a dislocation structure and deformation features such as mechanical twins, stacking faults, and slip bands. The presence of non-homogeneous strain and planar defects in the cold-rolled samples led to broader diffraction peaks compared to the annealed samples. The microstructure of the cold-rolled and artificially aged samples exhibited deformation features, dislocation structures, and ultra-fine precipitates. High-angle annular dark field imaging and energy-dispersive X-ray spectroscopy revealed that these precipitates were Ti-rich particles, which, along with molybdenum segregation in stacking faults, contributed to the highest hardness observed. X-ray diffraction analysis confirmed the segregation and depletion of alloying elements from the lattice during aging. Wear and corrosion tests demonstrated that while cold working and aging enhanced the wear performance of the annealed CoNiCrMo alloy, they adversely affected its corrosion resistance. Specifically, the volume loss for cold-worked and aged samples was approximately 2.7 and 2.1 times smaller than that of the annealed specimen, respectively. However, the annealed alloy exhibited a lower corrosion current density (icorr) of 70 nA cm−2 compared to the cold-worked and aged samples, which had icorr values of 130 and 200 nA cm−2, respectively.

One-Pot Fast Electrochemical Synthesis of Ternary Ni-Cu-Fe Particles for Improved Urea Oxidation

The climate crisis has become the most serious concern of human beings and environments worldwide in the 21st century. Global concerns about cancer epidemiology mainly originate from anthropogenic activities, particularly fossil-based operations. A key solution to this problem is the use of fuel cells—devices—capable of the direct conversion of fuel chemical energies like urea into electricity. To make their commercialization reasonable, one of the problems that needs to be solved is the development of anodic materials. The majority of investigations on urea oxidation are based on nickel, but its inadequate activity limits the efficiency of these devices. In this work, we propose and synthesize a Ni-Cu-Fe ternary electrocatalyst for urea oxidation through a fast and facile electrodeposition method. The properties of the synthesized material are examined by Scanning Electron Microscopy (SEM) conjugated with Energy Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). Its electrochemical properties were also examined in a 1 M KOH solution with and without 0.15 M urea. We found that the prepared powder is active in the electro-oxidation of urea, with 1.65 Vvs RHE required for a current density of 10 mA cm−2 and a stable potential of 2.38 Vvs RHE required for 3 h of polarization at 10 mA cm−2.

Fabrication of Zinc Oxide Thin Films by Sol-Gel Dip Coating Process

Zinc oxide (ZnO) is a non-toxic material known for its distinctive physical and chemical properties, including a direct band gap energy of 3.37 eV and a large exciton binding energy of 60 meV, which contribute to its significant thermal and chemical stability at room temperature. Due to these characteristics, ZnO plays a critical role in various applications, such as UV light emitters, transparent conducting thin films in electronic devices, gas sensors, piezoelectric materials, transducers, and as a transparent conductive oxide (TCO) layer in thin-film photoelectrochemical cells. Numerous fabrication techniques have been employed to produce ZnO thin films. However, many of these methods require costly equipment, high vacuum environments, and elevated temperatures. In contrast, the sol-gel process stands out as a convenient, cost-effective, and versatile method for ZnO thin film fabrication. It offers advantages such as simplicity, low crystallization temperature, ease of reproducibility, molecular-level homogeneity, and precise compositional control. In this study, ZnO thin films were deposited onto Indium Tin Oxide (ITO) glass substrates using the sol-gel dip coating method, with varying preparative parameters: sol concentrations and annealing temperatures. The resulting samples were characterized using a UV-visible spectrophotometer, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). The results demonstrated that the unique properties of ZnO thin films are highly dependent on the preparative parameters. Specifically, the band gap energy decreased from 3.25 eV to 3.18 eV with increasing sol concentration and also showed a similar decline with higher annealing temperatures. XRD patterns revealed a smaller full width at half maximum (FWHM) of the most intense peak (002) at higher sol concentrations and annealing temperatures, indicating an increase in crystallite size. FESEM images highlighted distinct morphological changes corresponding to the variations in sol precursor concentration and annealing temperature, while EDX analysis confirmed the formation of highly pure ZnO thin films on ITO glass substrates.

OPTIMIZATION OF HEAT TREATMENT REGIME FOR A NEW BIODEGRADABLE Mg-Zr-Nd ALLOY WITH ENHANCED MECHANICAL PROPERTIES

Purpose. To develop a rational heat treatment regime for a new biodegradable magnesium alloy of the Mg-Zr-Nd system, to ensure enhanced mechanical properties throughout the entire treatment period. Research methods. Differential thermal analysis (DTA) was used to determine phase transformation temperatures. Microstructure analysis was conducted using optical microscopy (“Neophot 32” and “OLYMPUS IX 70”) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SELMI RЕМ-106I). Mechanical properties were determined using an INSTRON 2801 testing machine. The influence of cooling rate on microstructure and properties was studied using ProCAST simulation software. Heat treatment was carried out in a Bellevue type shaft furnace and a PAP-4M furnace. X-ray analysis was used to detect internal defects in samples. Results. A new heat treatment regime was developed for the biodegradable Mg-3.15Nd-1.25Zr-0.6Zn (wt%) alloy. Using differential thermal analysis and microstructure studies at various quenching temperatures, the optimal quenching temperature was established at 560 °C. Empirical relationships describing the influence of heat treatment parameters on the alloy's microstructure were calculated. The new heat treatment regime (quenching from 560 °C for 8 hours, air cooling + aging at 200 °C for 16 hours) resulted in improved mechanical properties (UTS = 276–282 MPa, δ = 5.2–5.8%) compared to the standard T6 regime. Scientific novelty. For the first time, a comprehensive study of the influence of heat treatment parameters on the structure and properties of a new Mg-3.15Nd-1.25Zr-0.6Zn (wt%) alloy with increased content of alloying elements was conducted. New dependencies describing the influence of quenching temperature on the alloy's grain size were established. Practical value. A new heat treatment regime for the biodegradable magnesium alloy was developed, which ensures complete dissolution of the pseudoeutectic phase and formation of strengthening phases, resulting in improved mechanical properties compared to the standard alloy Mg-2.5Nd-0.4Zn-0.5Zr (wt%) and the standard T6 regime.

Decorating Cu2O with Copper Metal (Cu) through Facile Electrochemical Deposition for Methylene Blue Degradation

Cuprous oxide (Cu2O) thin film was decorated with copper metal (Cu) by the simple electrochemical deposition method. This study was motivated to improve the role of Cu as a co-catalyst due to the narrow band gap energy of known photocatalyst Cu2O. Cu was electrodeposited on Cu2O thin film with a substrate of indium tin oxide (ITO) at a voltage of -0.3V and a temperature of 60 °C in CuSO4 (pH 10) under a magnetic stirrer. The structure, phase, and morphology of Cu2O/Cu were characterised by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The electrocatalytic performance of Cu2O/Cu was recorded using linear sweep voltammetry and electrochemical impedance spectroscopy. XRD and SEM results show Cu was successfully deposited covering Cu2O. The current density of Cu2O/Cu increased by 2.7041 mA/cm2 confirming the lower charge current resistance of 2.48 kΩ. The Cu-decorated Cu2O demonstrated an improved photocatalytic activity, as shown by the increase of MB degradation from 46.33% to 50.87%. It was believed from characterisations that Cu deposition leads to more dense carriers and charge transfer, hence higher photocatalytic activity towards MB degradation than bare Cu2O thin film.

Fluorescent Microscopy Investigation of Cytotoxic Impact on MCF-7 Cell Line Treated With Zinc Nanoparticles Synthesized From Jania rubens.

Zinc nanoparticles (ZnNPs) are a viable option in a number of disciplines, including cancer treatment, due to their special features. Among the several techniques for synthesizing ZnNP, biosynthesis with natural extracts is a highly effective and environmentally benign method, especially for uses in biomedicine. Using an aqueous extract of the marine red seaweed Jania rubens, we created a unique biosynthetic technique in this study to manufacture ZnNPs. The produced ZnNPs have a characteristic flower-like form, as seen by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effective production of ZnNPs and the involvement of biomolecules in the synthesis process were validated by energy-dispersive X-ray spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FTIR) techniques. Using the MTT assay, the cytotoxic effects of the biosynthesized ZnNPs were evaluated, indicating their ability to inhibit MCF-7 breast cancer cells. Furthermore, ZnNPs' cytotoxicity against MCF-7 cells was validated by live/dead imaging experiments, which supported the MTT results.

Characterization of 3D printed composite for final dental restorations.

This study evaluated the mechanical, optical, microstructural, surface, and adhesive behavior of a 3D printing resin comparing it with a machinable resin composite. Specimens of different sizes and shapes were either printed (Vitality, Smart Dent) or machinable (Grandio Blocs, Voco GmbH) resin composites with similar composition were prepared. Surface and mechanical characterization were performed with Knoop hardness, flexural strength (three-point-bending), and elastic modulus tests. The wear of the tested materials was evaluated against steatite antagonists. The optical properties stability (color change, ΔE00, and translucency, TP00) were observed after staining in red wine. In addition, the bond strength of the resin composites to two resin cement protocols were investigated with microshear bond strength tests at baseline and after thermocycling. Scanning electron microscope (SEM) coupled with Energy-Dispersive X-ray Spectroscopy (EDS) was used for microstructural and chemical characterization. Statistical analyses were performed with t- and ANOVA tests. Hardness values (132.76 (16.32) KH- Machinable and 35.87 (2.78) KH - Printed), flexural strength (172.17 (26.99) MPa - Machinable and 88.69 (8.39) MPa - Printed), color and translucency change (1.86 (0.31)/0.06 - Machinable and 3.73 (0.36)/9,16- Printed), and wear depth (24.97mm (3.60)- Machinable and 7.16mm (2.84) - Printed) were statistically different. Average Regarding bond strength, mean values (MPa) for non-aged and aged groups were respectively 21.76 (6.64) / 31.9 (12.66) for Bifix cement (Voco GmbH, Cuxhaven, Germany) and 26.75 (5.14) / 24.36 (6.85) for Variolink cement (Ivoclar Vivadent, Schaan, Liechtenstein) in Printed and 17.79 (3.89) / 9.01 (3.36) ) for Bifix cement and 22.09 (6.55) / 11.01 (3.77) for Variolink cement in Machinable materials. The material and aging factors did affect bond strength but the cement factor did not (p = 0.202). No statistical differences were observed for mean roughness (Ra) between materials. The better dispersion and larger size of the inorganic particles in the Machinable resin were contrasted with the clustered smaller particles of printed resin, under SEM. The mechanical properties and color stability of the machinable resin were superior to those of the printed resin, probably due to the greater amount and dispersion of inorganic particles in the Mach resin, but bond strength after aging was stronger and more stable in the printed resin. 3D-printed resin composites with similar compositions to machinable resin composites do not necessarily exhibit the same properties, which can impact clinical performance. Understanding these differences can assist manufacturers in improving their materials and help clinicians distinguish between materials appropriate for provisional and final restorations.