Scientia Iranica
Volume:29 Issue: 6, Nov-Dec 2022

This study aims to synthesize bismuth oxide/activated carbon composites composed of rice husks for battery anodes and to determine the effect of bismuth nitrate pentahydrate mole variations on the characteristics of the resulting composites. The bismuth oxide/activated carbon composite synthesis was carried out using bismuth nitrate pentahydrate, sodium sulfate, and sodium hydroxide precursors which were mixed with rice husk-based activated carbon. A variation was made for the mole of bismuth nitrate pentahydrate used, while the compositions of activated carbon and other precursors were made fixed. The composites were synthesized using the hydrothermal method at a temperature of 1100C for 5 hours. The results showed that bismuth oxide was successfully formed as a composite in the 8 mmol variation with a composite electrical conductivity value of 2.40 x 10-3 S.m-1.

Nano CaO as a recyclable heterogeneous catalyst was synthesized via solution combustion method using Black pepper seed extract as a fuel, calcium nitrate as a source of calcium and characterized by various techniques such as XRD, FT-IR, EDAX, and SEM analysis. The catalyst was established a superior catalytic activity towards the synthesis of tetrazole analogues of protected amino acids in good yield via cycloaddition reaction of sodium azides with protected nitriles in methanol and water system under reflux condition. The synthesized N-protected tetrazoles were characterized by mass, FT-IR, 1H NMR, and 13C NMR. The experiment clarifies the shorter reaction time, inexpensive catalyst which is easily separable by simple filtration, and catalysts can be reused for several times without significant degradation in activity.

A simple, efficient, and high yielding one-pot protocol for the synthesis of pyrimido [4,5-b] quinoline derivatives has been developed. Pyrimido [4,5-b] quinolines were synthesized by three component reaction of 6-amino-2-(methylthio)pyrimidin-4(3H)-one, dimedone and various substituted aldehydes using Fe3O4@NCs/Ti(IV) as a magnetic natural-based catalyst in water at 70 °C. Several advantages of this protocol are good yields, short reaction times, easy work-up, recyclability and the environmentally benign of the catalyst. 6-Amino-2-(methylthio)pyrimidin-4(3H)-one as an important substrate was synthesized, purified, identified and then applied for the synthesis of pyrimido [4,5-b] quinolines. The structures of the products were confirmed by IR, 1H NMR and 13C NMR spectra.

In the current work, kinetic and dynamic parameters in reactive and non-reactive collisions between CN and OH radicals were investigated upon an interpolated potential energy surface using MP2/6-311G++(d,p) ab-initio method. The total and individual reaction probability and cross-section, for all reactions, were obtained and applied to calculate the rate constant and rate expression. In non-reactive trajectories, the effect of the impact parameter and relative translational energy of particles on the deflection angle was also investigated. To investigate the kinetic isotopic effect, the deuterium was used instead of hydrogen atom to illustrate the effect of mass of attacking radical and target molecule on physical observable such as reaction probability and cross-section

It has become a sustainable alternative solution to the concern of water scarcity in the current conditions of the industrial world. In this research, the effect of temperature and pH on efficiency, energy consumption, and outlet water quality from simple single-stage reverse osmosis systems, single-stage hybrid, simple two-stage, and two-stage hybrid are investigated by means of qPlus software. The results depicted that at all temperatures, the two-stage reverse osmosis system is more efficient in terms of efficiency, and the hybrid two-stage system has the best performance in terms of energy consumption. Also, the pH of the water entering the system has no effect on the efficiency and energy consumption of desalination plants. In terms of water quality, all four desalination plants have reduced the concentration of harmful ions to the desired level, but single-stage systems performed better than two-stage systems. In terms of corrosion index, two-stage systems performed better than single-stage systems. Also, the corrosion rate of water can be significantly reduced by increasing the temperature and adding sodium hydroxide. The results of this study can be utilized in the design of various desalination systems. Also, obtained results showed that by increasing the temperature, the operating pressure in the RO

Evaluation of behaviour of adsorbed layers of protein-surfactant mixture at the air-water interfaces have recently received great attention due to their wide applications in food and pharmaceutical industries. In this research, qualitative study of surface activity of two kinds of proteins, Beta- Lactoglobulin (BLG) and Beta-Casein (BCS), nonioinic surfactant of C10DMPO, and the mixtures of them in different concentrations at the air-water interface is investigated using rising bubble method. The similarity between measured local velocity profiles can be due to the fact that all mentioned materials are surface-active one and could create the Marangoni effect and develop a dynamic adsorption layer. As there is no significant interaction between the protein and surfactant molecules, stable complex structures cannot be formed in the protein-C10DMPO mixture. The mixture velocity profile is more similar to that of the surfactant which is a result of replacement of protein molecules or complexes with free surfactant at the bubble interface. It is found that the mixture of non-ionic surfactant with BCS has a bit synergetic effect while for its mixture with BLG, a negative synergy is observed which is resulted from the shape of protein.

The different nutrients in garlic provide numerous health benefits. As the most active and important bioactive compound found in garlic, allicin offers antimicrobial, anticancer, antioxidant, cholesterol-lowering and cardiovascular-preventive effects.Considering water as the solvent, garlic extraction was studied using ultrasonic bath technology based on the response surface methodology (RSM) for treatments created in Design-Expert 10 software package. The study was carried out at different temperatures (30-60°C), durations (10-30 min), powers (40-100 W) and frequencies (37 and 80 Hz). The extractions were evaluated for total phenolic content, DPPH test, and extraction efficiency. The optimum conditions were found to be 10 min, 30°C, 40 W and 37 Hz (R2= 0.99 for total phenolic content, R2= 0.93 for DPPH test and R2= 0.94 for extraction efficiency). Temperature and duration of sonication were the most influential parameters on the responses.It was concluded that ultrasonic apparatus can be conveniently used for extraction as it speeds up the process and reduces the required time, improving the quality of the extract in terms of antioxidant properties, the possibility of extraction of heat-sensitive compounds, etc.

In this study, the control of the release of urea fertilizer from the nanofibers substrate cellulose acetate polymer was investigated to increase the release time of fertilize it placed. First, cellulose acetate solution was prepared at concentrations of 14.13 and 15% and their nanofibers were produced by electrospinning. By checking the diameter and filamentation of fibers by FESEM images; concentrations of 14 %, as optimal concentration selected. Then cellulose acetate solution of 14 percent (Weight/Volume) containing concentrations of 17, 21 and 23 percent (Weight- Weight) of urea fertilizer, Compared to the weight of cellulose acetate prepared and nanofibers of cellulose acetate solutions containing urea was produced by electrospinning. FTIR test showed that between urea and cellulose acetate has no chemical reaction and fertilizer in the substrate of nanofibers are loaded. It also showed the DSC test, which fertilizer loaded on the bed of nanofibers; increases the degradation rate of cellulose acetate nanofibers. In addition, the release rate of urea fertilizer in distilled water was monitored by using a UV-vis spectrophotometer and the results showed that the release time was increased to 15 days, which is a significant amount.

Chemical reactions inside lithium-ion batteries generate heat and cause temperature rise. Hence, it is necessary to monitor battery time dependent heat generation. In this work, a hybrid model for simulating heat generation inside a pack of lithium batteries has been developed. An artificial neural network (ANN) has been employed to simulate electrochemical and thermal behaviors of a Panasonic NCR 18650 lithium-ion battery. In order to develop the hybrid model, the designed ANN has been inserted into ANSYS Fluent software through a C source code. A 3-D computation fluid dynamics (CFD) has been developed to simulate temperature distribution in the battery pack. Experimental data has been obtained using a NEWARE battery test system at different C-rates. The outputs of the proposed ANN consist of heat generation inside the battery as well as the electrochemical parameters. The combination of the ANN and CFD modeling, which led to a hybrid model, can be mentioned as the major contribution of this work. The results show an excellent consistency between the proposed model and test data. The simulation estimates the range of the manufacturer’s working temperatures (-20 to 60 oC), regarding the considered batteries.