Materials Science Forum Vol. 1083

Abstract: This study includes the preparation of the ferrite nanoparticles Cu_xCe_0.3-XNi_0.7Fe₂O₄ (where: x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) using the sol-gel (auto combustion) method, and citric acid was used as a fuel for combustion. The results of the tests conducted by X-ray diffraction (XRD), emitting-field scanning electron microscopy (FE-SEM), energy-dispersive X-ray analyzer (EDX), and Vibration Sample Magnetic Device (VSM) showed that the compound has a face-centered cubic structure, and the lattice constant is increased with increasing Cu ion. On the other hand, the compound has apparent porosity and spherical particles, and there are no other elements other than those participating in the preparation of the compound, which means that it is of high purity. The prepared compound possesses excellent magnetic properties due to the narrowness of the magnetic hysteresis ring. The gas sensing system found that the compound has good sensitivity to H₂S gas.

Abstract: In recent years, the materials industry has begun to develop in the directions on enabling the effect of nanomaterials. Nanomaterials are one of the most basic materials that have helped in the development of industrial technology because of their unique properties. These properties make them spread in many areas, especially in the electrical and thermal. Still, traditional materials, at present, suffer from issues that restrict their use, such as thermal conductivity and electrical conductivity. Currently, nanomaterials owing to outstanding performance those traditional materials do not possess. In contrast, scientists have recently focused their efforts on increasing the (electrical and thermal) applications of epoxy resins. In this study, we combined nanoparticles (CaTiO3) with type epoxy resin (Quickmast 105) with different concentrations of CaTiO₃ (0, 0.01, 0.02, 0.03, 0.04, 0.05 wt%) by casting. Several tests such as thermal conductivity, thermal expansion, electrical conductivity, dielectric constant and dielectric loss have been carried out. The test results showed a significant increase in thermal conductivity with increasing concentrations of nanoparticles in epoxy, decreasing thermal expansion by 28%, and increasing AC conductivity for all concentrations. The relative permittivity (dielectric constant) of epoxy nanocomposites remains nearly constant with increasing frequency. For dielectric loss, it can be seen that the epoxy nanocomposite's tan values are increasing also with high concentrations.

Abstract: Chemical engineering frequently uses "process intensification" to consciously combine various phenomena or procedures. By treating the molecules in such a system in a way that every single molecule experiences the same processing, the selectivity is raised, enhancing productivity. For mass transfer limited reactions, the enhancement of the transport rates & the specific interfacial area are the typical approaches. These enable the reduction of diffusion path length, reduce hold-up and improve the controlling on temperature control, even for highly exothermic reactions. Micro reactor technology (MRT) is a subset of process intensification that aims to reduce the size of equipment, energy consumption, and waste generation. The research of peracetic acid (PAA) and perform acid (PFA) preparation is the focus of the current investigation. Amberlite IR-120H catalyst was used to study the synthesis of PAA and PFA in batch and micro-structured reactors while ultrasonic irradiations were present.. The current research describes a method for synthesizing both compounds in a batch and micro-structured reactors, with and without ultrasonic irradiation. Such a technology might be crucial in the online synthesis of these chemicals as it eliminates the need for harmful components to be transported and stored, assuring safety among other benefits. For these substances, various safety characteristics could be improved.

Abstract: Synthesis of silver nanoparticles (AgNP) by pulsed liquid laser ablation (PLAL) produces AgNPs that are better suited for biological applications compared to those prepared by standard wet-chemical methods. These were mainly achieved by water ablation with pulse widths in the nanosecond range. In the case of surface NP activation, we previously detected a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs. To do this, we dilute Colloid slightly with LiCl. These surface alterations may have an effect on the NPs' capability to combat bacteria. every time, AgNPs with a median diameter of under ten nm were created., that has been incontestible in alternative studies to be the optimum size for germicidal activity.. Furthermore, minimum restrictive concentration (MIC) values for LiCl-modified AgNPs fell inside a slender vary of 1.1-3.8 g/mL, creating them the foremost efficient. This result's believed to be explained by the metal surface's enhanced surface reactivity, which is brought on by the existence of charged active sites.

Abstract: The performance of a surface Plasmon resonance (SPR) sensor with silver film was demonstrated. The Kretschmann setup's evanescent field, which can activate the sensor. The sensitivity and FWHM of the SPR sensor drop as the thickness of the silver layer in the metallic film increases. Using water as a sensing medium, it can create a simulation model at various thicknesses of the silver layers placed on the semicircular glass prism D-ZLAF50 with a thickness of dAg = 10–80 nm. The proposed sensor can function at wavelengths of up to 600,700nm in the visible area and the infrared region at wavelengths of 900 & 1000 nm. Optimum sensitivity (S = 100–140) may be observed in the visible and infrared spectrum with thicknesses ranging from d_Ag = (10–80) nm , ∆n = 0.1. At silver layer thicknesses, the values of SPR dip length and FWHM are excellent (40–60 nm).

Abstract: The present work describes a heat treatment procedure using nanofluids as quenchants for (AISI 52100 Steel) via the Taguchi method to optimize process parameters. The nanofluids have been prepared from nanoparticles (SiO₂, SiC and Fe₂O₃) and base media consist of distilled water, toluene and ethylene glycol of volume concentrations of 0.02, 0.04 and 0.06 %. The present investigation considers hardness and wear rate as optimization criteria. The experimental variables that were selected for this study are: (austenitizing and tempering temperature), (type and volume fraction of nanoparticles) and (base media). They represent significant factors that influence on these optimization criteria. (AL18 orthogonal array), (analysis of variances (ANOVA)) and (signal/noise ratio (S/N)) were applied by means of (Minitab 18) software to examine the performance characteristics of the process parameters. The analysis of (S/N) ratio shows that the most significant parameters that give the optimum heat treatment conditions for hardness of the examined steel (AISI 52100) are: (austenitizing temperature of 800°C), (distilled water as a type of base media) and (tempering temperature of 180°C), in addition to (Fe₂O₃ as a nanoparticles type) and finally (nanoparticles volume fraction of 0.06%). In contrast, for the wear rate, they were: (austenitizing temperature of 800°C), type of base media (distilled water), tempering temperature of (180°C), and volume fraction of nanoparticles (0.06%) tempering. Finally, nanoparticles type (Fe₂O₃) is the most significant parameter for hardness and wear rate. ANOVA, exhibited that the austenitizing temperature has major effect on producing high values of hardness and wear rate for the AISI 52100 Steel.

Abstract: The paper deals with changes in the stoichiometry of nanopowders obtained under staged irradiation of a brass ingot placed in a graphite crucible. Composite core-shell CuO/ZnO nanoparticles, copper nanoparticles, and copper and zinc oxides were obtained. The use of a relativistic electron accelerator is necessary to produce nanopowders on an industrial scale. Transmission electron microscopy and energy-dispersive analysis of the obtained nanoparticles were carried out. Thermodynamic calculation of the temperature dependence of the equilibrium content of copper and zinc is presented for the condensed and gas phases. The formation mechanism of CuO/ZnO composite nanoparticles is discussed.

Abstract: The zinc oxide nanoparticles were synthesized to investigate the ultraviolet light absorbance and transmittance for applications of UV protection. Zinc oxide nanoparticles were characterized by photon cross-correlation and ultra-violet spectrophotometers. The results show that the synthesized zinc oxide nanoparticles have the mean diameter of ~35 nm of main particles with particle size distribution range from ~11 nm to ~80 nm.The use of synthesized nanoparticles achieved transmission levels of over 95 % in the UVA regions at the wavelength range of 320-400 nm.

Abstract: The novel bicycloamino acid, 1−carboxyl−4−amino−2−aza−3−oxo−[2.2.2] bicyclooctane was synthesized and its physical characteristics have been compared to those predicted using quantum chemical calculations. The crystal structure of novel compound was determined by X-ray diffraction measurements at room temperature. Unit cell is monoclinic, with space group P 2₁/n (14) and a = 5.8587(6) Ǻ, b = 11.2454(16) Ǻ, c = 13.9723(16) Ǻ, β=97.840(6)°, Z = 2. Refinement was performed using all 1598 reflections with R = 0.4085 and wR = 0.6024. Theoretical calculation of full optimization and atomic net charge, and frontier orbital energies of the title compound was carried out at the B3LYP/6−31G(d,p) level. The NMR chemical shielding tensors and vibrational frequencies were calculated with B3LYP/6-311+G(2d, p)− level in which were close values and similar spectrum structures with experimental results and used to interpret the experimental measurements.