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61.
Mahboubi Davoud Jafari Gavzan Iraj Saidi Mohammad Hassan Ahmadi Naghi 《Journal of Thermal Analysis and Calorimetry》2022,147(21):12253-12267
Journal of Thermal Analysis and Calorimetry - Lithium-ion batteries should continuously be operated at the optimum temperature range $$left( {15 sim 40 ,^circ C} right)$$ for the best... 相似文献
62.
Alireza Jahangiri Majid Saidi Farhad Salimi Abolfazl Mohammadi 《Research on Chemical Intermediates》2018,44(3):1755-1773
In this study, nano catalyst LaNiO3 with perovskite structure was synthesized using the citrate sol–gel method in the combined methane reforming with CO2 and O2 (CRM). The effects of increasing the surface area of the LaNiO3 perovskite on the catalytic activity were investigated by changing the method of preparing and creating holes in the surface of the samples. Physical and chemical properties of the samples, before and after the reactor test, were determined through ICP, AA, XRD, TGA, TPR, BET, SEM, EDX and TEM techniques. The results of XRD, ICP, AA, SEM, EDX and TEM tests indicated that the citrate sol–gel method is a good way to prepare a homogeneous perovskite LaNiO3 sample on a scale of nanometers. The results of the TPR test showed using etching in the citrate sol–gel method can produce samples with high stability. The BET results indicated that the surface area of the LaNiO3 sample tripled with the method suggested in this paper. Changes in preparation method lead to induction time decreasing and temperature increasing. Use of etching in the citrate sol gel method had no significant effect in the results of activity tests versus time reaction at a temperature of 800 °C. TGA curves revealed no production of coke over the process for the produced samples. 相似文献
63.
Hamid Reza Rahimpour Majid Saidi Parisa Rostami Bruce C. Gates Mohammad Reza Rahimpour 《国际化学动力学杂志》2016,48(11):702-713
Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored. 相似文献
64.
M. R. Saidi R. Stan Brown A. Ziyaei-Halimjani 《Journal of the Iranian Chemical Society》2007,4(2):194-198
A one-pot high yielding reductive amination of aldehydes with primary and secondary amines using LiClO4/NaBH4 and LiClO4/LiAlH4 as reducing agents in diethyl ether is described. 相似文献
65.
Samah H. Abu-Hussien Bahaa A. Hemdan Othman M. Alzahrani Amal S. Alswat Fuad A. Alatawi Muneefah Abdullah Alenezi Doaa Bahaa Eldin Darwish Hanouf S. Bafhaid Samy F. Mahmoud Mohamed F. M. Ibrahim Salwa M. El-Sayed 《Molecules (Basel, Switzerland)》2022,27(19)
Malachite green (MG) dye is a common environmental pollutant that threatens human health and the integrity of the Earth’s ecosystem. The aim of this study was to investigate the potential biodegradation of MG dye by actinomycetes species isolated from planted soil near an industrial water effluent in Cairo, Egypt. The Streptomyces isolate St 45 was selected according to its high efficiency for laccase production. It was identified as S. exfoliatus based on phenotype and 16S rRNA molecular analysis and was deposited in the NCBI GenBank with the gene accession number . Its growth kinetics were studied during an incubation time of 144 h, during which the growth rate was 0.4232 (µ/h), the duplication time (td) was 1.64 d, and multiplication rate (MR) was 0.61 h, with an MG decolorization value of 96% after 120 h of incubation at 25 °C. Eleven physical and nutritional factors (mannitol, frying oil waste, MgSO4, NH4NO3, NH4Cl, dye concentration, pH, agitation, temperature, inoculum size, and incubation time) were screened for significance in the biodegradation of MG by S. exfoliatus using PBD. Out of the eleven factors screened in PBD, five (dye concentration, frying oil waste, MgSO4, inoculum size, and pH) were shown to be significant in the decolorization process. Central composite design (CCD) was applied to optimize the biodegradation of MG. Maximum decolorization was attained using the following optimal conditions: food oil waste, 7.5 mL/L; MgSO4, 0.35 g/L; dye concentration, 0.04 g/L; pH, 4.0; and inoculum size, 12.5%. The products from the degradation of MG by S. exfoliatus were characterized using high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The results revealed the presence of several compounds, including leuco-malachite green, di(tert-butyl)(2-phenylethoxy) silane, 1,3-benzenedicarboxylic acid, bis(2-ethylhexyl) ester, 1,4-benzenedicarboxylic acid, bis(2-ethylhexyl) ester, 1,2-benzenedicarboxylic acid, di-n-octyl phthalate, and 1,2-benzenedicarboxylic acid, dioctyl ester. Moreover, the phytotoxicity, microbial toxicity, and cytotoxicity tests confirmed that the byproducts of MG degradation were not toxic to plants, microbes, or human cells. The results of this work implicate S. exfoliatus as a novel strain for MG biodegradation in different environments. OL720220相似文献
66.
In this research work, an exact analytical solution for buckling of functionally graded rectangular plates subjected to non-uniformly
distributed in-plane loading acting on two opposite simply supported edges is developed. It is assumed that the plate rests
on two-parameter elastic foundation and its material properties vary through the thickness of the plate as a power function.
The neutral surface position for such plate is determined, and the classical plate theory based on exact neutral surface position
is employed to derive the governing stability equations. Considering Levy-type solution, the buckling equation reduces to
an ordinary differential equation with variable coefficients. An exact analytical solution is obtained for this equation in
the form of power series using the method of Frobenius. By considering sufficient terms in power series, the critical buckling
load of functionally graded plate with different boundary conditions is determined. The accuracy of presented results is verified
by appropriate convergence study, and the results are checked with those available in related literature. Furthermore, the
effects of power of functionally graded material, aspect ratio, foundation stiffness coefficients and in-plane loading configuration
together with different combinations of boundary conditions on the critical buckling load of functionally graded rectangular
thin plate are studied. 相似文献
67.
Thermoelastic buckling behavior of thick rectangular plate made of functionally graded materials is investigated in this article.
The material properties of the plate are assumed to vary continuously through the thickness of the plate according to a power-law
distribution. Three types of thermal loading as uniform temperature raise, nonlinear and linear temperature distribution through
the thickness of plate are considered. The coupled governing stability equations are derived based on the Reddy’s higher-order
shear deformation plate theory using the energy method. The resulted stability equations are decoupled and solved analytically
for the functionally graded rectangular plates with two opposite edges simply supported subjected to different types of thermal
loading. A comparison of the present results with those available in the literature is carried out to establish the accuracy
of the presented analytical method. The influences of power of functionally graded material, plate thickness, aspect ratio,
thermal loading conditions and boundary conditions on the critical buckling temperature of aluminum/alumina functionally graded
rectangular plates are investigated and discussed in detail. The critical buckling temperatures of thick functionally graded
rectangular plates with various boundary conditions are reported for the first time and can be served as benchmark results
for researchers to validate their numerical and analytical methods in the future. 相似文献
68.
The thermal degradation behaviour and the gaseous products of FEP-g-polystyrene sulfonic acid membranes prepared by radiation-induced grafting of styrene onto poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films and the subsequent sulfonation were studied using thermal gravimetric analysis coupled with Fourier transform infrared spectrometry (TGA/FTIR). The membranes were found to have a three-step degradation behaviour due to water removal, elimination of sulfonic acid groups and decomposition of the FEP matrix. The evolving gaseous products were identified using FTIR analysis. The degree of grafting was found to have a strong effect on the weight loss in the membranes, whilst the degradation temperatures of the individual membrane components were shown to be independent of the degree of grafting. 相似文献
69.
In this paper, the stress analysis of moderately thick functionally graded sector plate is developed for studying the singularities in vicinity of the vertex and effects of boundary layer. Based on the first-order shear deformation plate theory, the governing partial differential equations are obtained. Using an analytical method, the stretching and bending equilibrium equations are decoupled. Also, introducing a function, called boundary layer function, the three bending equations are converted into two decoupled equations. These equations are solved analytically and the effects of boundary layer function on stress components are shown. Also, the singularities of shear force, moment resultants and boundary layer function are discussed for both salient (α?180) and re-entrant (α>180) sectorial plates. In order to verify the accuracy of the results, the governing equations are also solved using differential quadrature method (DQM). By comparing the results of exact method with DQM, a good agreement can be seen. 相似文献
70.
An operationally simple and entirely green protocol for heteropoly acid (10 mg) catalyst conjugate addition of indoles and pyrrole to unsaturated carbonyl compounds and nitroalkene in water at ambient temperature in good to excellent yields has been developed. 相似文献