Synthesis and Characterization of Orthophosphate Silver Powders

AbstractOrthophosphate silver with superior quality and quantum size effect is elaborated by precipitation from phosphate precursors. The powders were investigated by X-ray diffraction, SEM-EDS, FTIR, thermal analysis, and diffuse reflectance. Spherical like Ag3PO4 particles with size between 0.8 to 10μm were obtained. The powders crystallize in a cubic symmetry and the smaller crystallites are obtained with Na2HPO4 The optical gap, determined from the diffuse reflectance spectra through the Kubelka-Munk function, lies between 2.05 and 2.30eV

Optimization of an Alkylpolyglucoside-Based Dishwashing Detergent Formulation.

The aim of this work was to formulate and optimize the washing performance of an alkylpolyglucoside-based dishwashing detergent. The liquid detergent was formulated with five ingredients of commercial origin: anionic (linear sodium alkylbenzenesulfonate and sodium laurylethersulfate), nonionic (C12–C14 alkylpolyglucoside) and zwitterionic (a fatty acid amide derivative with a betaine structure) surfactants, and NaCl for viscosity control. In addition to the plate test, other properties were investigated including ‘‘cloud point’’, viscosity, and emulsion stability. Statistical analysis software was used to generate a central composite experimental design. Then, a second order design and analysis of experiments approach, known as the Response Surface Methodology, was set up to investigate the effects of the five components of the formulation on the studied properties in the region covering plausible component ranges. The method proved to be efficient for locating the domains of concentrations where the desired properties were met

Influence of growth conditions of hydrogenated amorphous silicon carbide on optical properties of the interfacial layer in SiC-based photodevice

The attention has been focused on the optical properties of structures of the form Au/MS/a-Si_{1-x}C_x:H/Si(100)/Al as a function of the deposition temperature of the a-Si_{1-x}C_x:H films. The amorphous SiC:H films were obtained for different temperatures ranging from 150°C up to 500°C. By photoluminescence, blue emission from all the structures was observed at room temperature and a high emission was obtained for sample whose amorphous film was deposited at 500°C. The spectral response of Au/MS/a-Si_{1-x}C_x:H/Si(100)/Al structures with a-Si_{1-x}C_x:H film deposited at 250°C, exhibits a maximum value at λ=950 nm while for structure with a-Si_{1-x}C_x:H film obtained at 150°C, a maximum value of λ was observed at 400 nm

Photochemical Conversion of CO₂ into Methyl Alcohol Using SiC Micropowder under UV Light

In our study, microparticles SiC powder was investigated as a catalyst for CO₂ photoreduction into methanol under UV light. The photochemical conversion of methanol was studied as function of time of exposition, the concentration and the grain size of the catalyst. The selectivity of the used catalyst to promote methanol formation was noticed. It was noticed also that the grain size and concentration have a great impact on the photochemical conversion of CO₂ to methanol. The best yield of methanol was achieved when a concentration of 0.75 M of SiC powder of 17 μm grain size and an exposure time to UV light of 2 h where assured. Maximum molar concentration of methanol achieved was under UV irradiation of 365 nm. Therefore, the catalytic property of silicon carbide has proved its efficiency in the photochemical conversion of CO₂ into alcohol thus far under UV light

Preparation of Silver Powder used for Solar Cell Paste by Reduction Process

AbstractThe preparation of fine silver particles is getting great attention due to their applications in electrical fields such as the fabrication of conductive pastes used in solar cell metallization. This study deals with the preparation of silver powders by a chemical reduction method using silver nitrate as a starting material, and either sodium or ammonium hydroxides as reactants, and formaldehyde as a reducing agent. The effects of ratio change between the silver nitrate and the base concentrations, on the characteristics of the silver micro particles, were examined. The physicochemical properties of the powders were evaluated using XRD, SEM, and granulometry. It was shown that the particle size and shape of the powder depend on the molar ratio of silver nitrate to base and, on the base nature

Performance and Efficiency of Anionic Dishwashing Liquids with Amphoteric and Nonionic Surfactants

Performance and efficiency of anionic [sodium lauryl ether sulfate (SLES) and sodium alpha-olefin sulfonate (AOS)] and amphoteric [cocamidopropyl betaine (CAB)] as well as nonionic [cocodiethanol amide (DEA), various ethoxylated alcohols (C-12-C-15-7EO, C-10-7EO and C-9-C-11-7EO) and lauramine oxide (AO)] surfactants in various dishwashing liquid mixed micelle systems have been studied at different temperatures (17.0, 23.0 and 42.0 degrees C). The investigated parameters were critical micelle concentration (CMC), surface tension (gamma), cleaning performance and, foaming, biodegradability and irritability of anionic (SLES/AOS) and anionic/amphoteric/nonionic (SLES/AOS/CAB/AO) as well as anionic/nonionic (SLES/AOS/DEA/AO, SLES/AOS/C-12-C-15-7EO/AO, SLES/AOS/C-10-7EO/AO and SLES/AOS/C-9-C-11-7EO/AO) dishwashing surfactant mixtures. In comparison to the starting binary SLES/AOS surfactant mixture, addition of various nonionic surfactants promoted CMC and gamma lowering, enhanced cleaning performance and foaming, but did not significantly affect biodegradability and irritability of dishwashing formulations. The anionic/nonionic formulation SLES/AOS/C-9-C-11-7EO/AO shows both the lowest CMC and gamma as well as the best cleaning performance, compared to the other examined dishwashing formulations. However, the results in this study reveal that synergistic behavior of anionic/nonionic SLES/AOS/ethoxylated alcohols/AO formulations significantly improves dishwashing performance and efficiency at both low and regular dishwashing temperatures (17.0 and 42.0 degrees C) and lead to better application properties