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In the last few years, the COVID-19 pandemic has increased the usage of antigen rapid test (ART) kits and improper disposal of these kits has led to the mixing of toxic chemical compounds present in the ART reagent solution container into drinking water sources. When consumed with drinking water, these compounds can be harmful and toxic to both humans and aquatic life. Therefore, this research presents a study on the photocatalytic degradation of the Antigen Rapid Test-Reagent solution (ART-RS) using a single-phase titanium oxycarbide - TiO0.25 C0.75 (TiOC) photocatalyst synthesized through a solid-state reaction. The synthesized samples were studied using various characterization tools to analyze their structural, morphological, and optical characteristics. In the photocatalytic experiment, it was found that the synthesized titanium oxycarbide photocatalyst exhibited superior ART-RS degradation efficiency of 77% compared to commercial titanium dioxide (22%). The improved photocatalytic degradation efficiency of ART-RS is attributed to a combination of several factors. These factors include a narrower band gap, more efficient charge transfer kinetics, enhanced absorption of visible light, and an upward shift of the valence band (VB) edge in titanium oxycarbide. These collective effects contribute to the enhanced ART-RS photocatalytic degradation activity [ABSTRACT FROM AUTHOR]

The nonisothermal crystallization kinetic of Bi xY3− xFe5O12 (0.25≤ x≤1.00) powders prepared by coprecipitation process has been investigated. The activation energy of crystallization was calculated by differential scanning calorimetry at different heating rates. The activation energies of crystallization of Bi xY3− xFe5O12 system are 492, 447, 377, and 353 kJ/mol and the Avrami constant n are 3.49, 2.25, 2.48, and 2.33 for x=0.25, 0.50, 0.75, and 1.00, respectively. The Avrami exponent values (1< n<3) were consistent with surface and internal crystallizations occurring simultaneously for 0.50≤ x≤1.00, the value ( n>3) for the Avrami exponent was consistent with bulk crystallization domination in Bi xY3− xFe5O12 system. The results reveal that increasing the substitution amount of bismuth for yttrium would significantly decrease activation energy in Bi xY3− xFe5O12 system. [ABSTRACT FROM AUTHOR]

The microstructure, thermal expansion, mechanical property, and ionic conductivity of samaria-doped ceria (SDC) prepared by coprecipitation were investigated in this paper. The results revealed that the average particle size ranged from 10.9±0.4 to 13.5±0.5 nm, crystallite dimension varied from 8.6±0.3 to 10.7±0.4 nm, and the specific surface area distribution ranged from 62.6±1.8 to 76.7±2.2 m2/g for SDC powders prepared by coprecipitation. The dependence of lattice parameter, a, versus dopant concentration, x, of Sm3+ ion shows that these solid solutions obey Vegard's rule as a ( x)=5.4089+0.10743 x for Ce1− xSm xO2−1/2 x. For SDC ceramics sintered at 1500°C for 5 h, the bulk density was over 95% of the theoretical density; the maximum ionic conductivity, σ800°C=(22.3±1.14) × 10−3 S/cm with minimum activation energy, Ea=0.89±0.02 eV, was found in the Ce0.80Sm0.20O1.90 ceramic. A dense Ce0.8Sm0.2O1.9 ceramic with a grain size distribution of 0.5–4 μm can be obtained by controlling the soaking time at 1500°C. When the soaking time was increased, the microhardness of Ce0.8Sm0.2O1.9 ceramic increased, the toughness slightly decreased, which was related to grain growth with the soaking time. [ABSTRACT FROM AUTHOR]

The crystallization kinetics of Bi0.5Y2.5Fe5O12 powders prepared by the coprecipitation process have been investigated. The activation energy of crystallization was calculated on the basis of differential scanning calorimetry at different heating rates. Analysis of nonisothermal DSC data yielded a value of 823.8 kJ/mol and 2.25 for the activation energy of crystallization and the Avrami exponent, respectively. This value for the Avrami exponent was consistent with surface and internal crystallization occurring simultaneously. The complex permittivity and permeability of Bi0.5Y2.5Fe5O12 was measured at the X-band (8–12 GHz) using the cavity perturbation technique. For dielectric properties, the real part of permittivity, ℇ′, was obtained in the range of 13.57–16.37. For magnetic properties, the real part of permeability, μ′, was obtained in the range of 21.61–16.90. [ABSTRACT FROM AUTHOR]

Europium-doped yttrium phosphors were successfully synthesized by combustion process using yttrium nitrate hexahydrate [Y(NO3)3·6H2O], europium nitrate [Eu(NO3)3·6H2O], and carbohydrazide [CO(N2H3)2]. The process takes only a few minutes to obtain Y2O3:Eu phosphors. The resultant powders annealed at different temperature and were investigated by X-ray diffractometer (XRD), differential thermal analyzer/thermogravimeter (DTA/TG), Fourier transform infrared spectroscopy (FTIR), photoluminescence excitation and emission spectra (PL), and transmission electron microscopy (TEM). The results showed that the formation temperature of Y2O3 phase is significant low, compared to solid-state reaction route of constituent oxides. For luminescence property, the emission intensity of Y2O3:Eu phosphors synthesized by combustion process increases steadily with increasing europium amount from 1 mol% to 5 mol%. [ABSTRACT FROM AUTHOR]

Spinel LiMn2 − xCoxO4 (0.00 ≦ x ≦ 0.20) powders with small and uniform particle size were successfully synthesized by microwave-induced combustion using lithium nitrate, manganese nitrate, cobalt nitrate, and urea as the starting materials. The LiMn2 − xCoxO4 powders synthesized by microwave-induced combustion were investigated by X-ray diffractometer (XRD), thermogravimeter analyzer (TG), and scanning electron microscopy (SEM). The LiMn2 − xCoxO4 samples were used as cathode materials in lithium-ion batteries, whose discharge capacity and electrochemical characteristics such as the cycling performance were also investigated. The results revealed that the LiMn2 − xCoxO4 cell synthesized by microwave-induced combustion provided a high initial capacity and excellent reversibility compared to the material prepared by solid-state reaction method. [ABSTRACT FROM AUTHOR]

The synthesis and microwave characterization of glass ceramic in the quaternary phase field of the MgO-CaO-Al2O3-SiO2 system synthesized by sol-gel method have been investigated in this paper. The glass powder was obtained by calcining the MgO-CaO-Al2O3-SiO2 xerogel, which was prepared from Magnesium nitrate hexahydrate (Mg(NO3)2·6H2O), Aluminum nitrate nonahydrate (Al(NO3)3·9H2O), Calcium nitrate tetrahydrate (Ca(NO3)2·4H2O), and tetraethylortho silicate (TEOS). The powder was characterized by differential thermal analysis, thermogravimety and X-ray diffraction. The calcined powder was pressed, sintered at different temperatures, and then the sintered sample was studied with scanning electron microscope, X-ray diffraction patterns, and microwave properties measurement. [ABSTRACT FROM AUTHOR]

In this article, structural properties and bonding behaviours of codoped lanthanum chromites (La0.8Ca0.2)(Cr0.9 - xCo0.1Cux)O3 (x = 0.00, 0.03, and 0.12) were investigated in detail. Polycrystalline chromite samples (La0.8Ca0.2)(Cr0.9 - xCo0.1Cux)O3 (x = 0.00, 0.03, and 0.12) were prepared by a standard solid-state reaction process. The synthesised samples were characterised for their structural, morphological, optical, and magnetic properties using powder XRD, SEM/EDS, UV-Vis, and VSM. XRD data showed that the samples were crystallised into a single phase with orthorhombic structure. Powder profile refinement analysis suggested the reduction in lattice parameters and cell volume with the addition of Cu. The electron density distributions and the bonding features of the prepared samples have been investigated using maximum entropy method (MEM). The mid bond electron density values revealed the enhancement of ionic nature between lanthanum and oxygen ions and a reduction in covalent nature between chromium and oxygen ions. Heterogeneous distribution of particles with different sizes was observed through SEM micrographs. EDS spectra confirms the presence of constituent elements in the prepared samples. Optical band gap values are decreasing with the addition of Cu. Antiferromagnetic ordering was observed from M-H curves obtained at room temperature. The structural and the magnetic properties are correlated. [ABSTRACT FROM AUTHOR]

CIGS polycrystalline thin films were successfully fabricated by one-step cathodic electrodeposition on Mo-coated glass. In this study, we applied a galvanometry mode with three-electrode potentiostatic systems to produce a constant concentration electroplating solution, which were composed ofCuCl2, InCl3, GaCl3, andSeO2. Then these as-electrodeposited films were annealed in argon atmosphere and characterized by X-ray diffraction. The results revealed that annealing treatment significantly improved the crystallinity of electrodeposited films and formed CIGS chalcopyrite structure, but at low applied deposition voltage (-950 mV versus SCE) there appeared second phase. The cross-section morphology revealed that applied voltage at -1350 mV versus SCE has uniform deposition, and higher applied voltage made grain more unobvious. The deposition rate and current density are proportional to deposition potential, and hydrogen was generated apparently when applying potential beyond -1750 mV versus SCE. It was found that the CIGS compound did not match exact stoichiometry of Cu : In : Ga : Se = 1: x : (1 - x) :2. This result suggests the possibility of controlling the property of thin films by varying the applied potential during electrodeposition. [ABSTRACT FROM AUTHOR]

Paper sludge is a major waste by-product of the paper industry. Its disposal creates serious problems, as approximately 30% of treated sludge is not flammable. In this study, artificial lightweight aggregates (ALWAs) were synthesized from paper sludge by co-sintering with H3BO3. H3BO3 acts as a flux to lower the sintering temperature below 900 °C, with co-melting occurring during the procedure. The decomposition gas is sealed within the ALWA during the glassy phase to form a porous structure. Water absorption, apparent porosity, bulk density, compressive strength, and weight loss after rinsing with Na2SO4 were tested to understand the physical properties of the manufactured ALWAs. The optimal method suggested is co-sintering with 18% H3BO3 flux at 890 °C for 30 min. The tested properties mentioned above gave the following results: 4.64 %, 2.77 %, 0.6 g/cm³, 13.2 MPa, and < 0.1 %, respectively. The ALWAs produced in this study have been compared to commercially available lightweight aggregates - Lytag and Arlita - with the examined ALWAs possessing better qualities than Lytag. Water absorption and compressive strength of ALWAs in this study met government requirements of pre-stressed concrete necessary for civil works, and could make useful building material. [ABSTRACT FROM AUTHOR]

In this study, we propose a process to prepare Mn–Zn ferrite powder, using oxides of manganese and zinc extracted from used dry batteries, and ferrous chloride solution from waste steel pickling liquor. The hydrothermal process was used to convert the starting raw materials into Mn–Zn ferrite powder. This powder revealed the formation of cubic ferrite with a saturation magnetization ( Ms) of 58.8 emu/g and an intrinsic coercive force ( Hc) of 3.8 Oe. The average lattice thermal expansion coefficient αa (200°–500°C) of this Mn–Zn ferrite powder was 14.14 × 10−6 K−1. The toroidal specimen sintered at 1300°C in a controlled oxygen atmosphere presented a flat profile of initial permeability (μi) of 2150–2200, in the frequency range 0.1–20 kHz, which allows its use in magnetic applications. This useful technology, combined with environment and materials engineering, can promote the recycling of dry batteries and contribute to the preservation of the earth. Moreover, this technology can also decrease the cost of disposal of the used dried batteries and waste steel pickling liquor. [ABSTRACT FROM AUTHOR]

• Ce 0.8 Sm 0.1 Gd 0.1 O 1.90 (CSGO) thin film was successfully deposited by PLD. • Columnar growth observed at higher oxygen partial pressure. • Stabilization of the Ce4+ state with lower Ce3+ concentration by Sm co-doping. • NiO-GDC10/CSGO half cell shows σ 973 K = 0.11 mS.cm−1 and Ea = 0.45 eV. Thin film electrolytes of Sm and Gd doubly co-doped ceria, namely, Ce 0.8 Sm 0.1 Gd 0.1 O 1.90 (CSGO) deposited by pulsed laser deposition (PLD) technique have been investigated. The influence of oxygen partial pressure (pO 2) on structural and morphological properties of CSGO thin films deposited on Si (111) substrate was studied by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM) techniques. The XRD and FESEM results showed that the films were polycrystalline cubic structure with (111) oriented columnar structure. The co-doping strategy has strongly helped to stabilize the Ce4+ state as the lattice parameter of the films did not show any significant change under the influence of pO2 in the range of 2 × 10-4-3 × 10-2 mbar. The electrical conductivity and activation energy of CSGO thin film supported on NiO-GDC10 anode were found to be 0.48 mS.cm−1 and 0.5 eV respectively. Determination of significantly lower Ce3+ concentration (27%) in CSGO film by X-ray photon electron spectroscopy (XPS) suggests that Sm-Gd co-doping has strongly suppressed the conversion of Ce4+ to Ce3+ in the overall composition. [ABSTRACT FROM AUTHOR]

This review of literature published in 2014 focuses on waste related to chemical and allied products. The topics cover the waste management practices, hospital waste, pesticide waste, chemical wastewater, pesticide wastewater and pharmaceutical wastewater. The other topics include aerobic treatment, anaerobic treatment, sorption and ozonation. [ABSTRACT FROM AUTHOR]

A review of the literature published in 2011 on topics related to chemicals and allied products is presented. The review considered several sections such as waste management, physicochemical treatment, aerobic treatment, anaerobic treatment, air emissions, soils and groundwater, and reuse. [ABSTRACT FROM AUTHOR]