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Efficient one-pot synthesis of 1,3-diaryl-3H-benzo[f]chromenes using ferric hydrogensulfate

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Chinese Chemical Letters 2010年第12期21卷 1423-1426页

作者： hossein Eshghi Gholam hossein Zohuri Saman Damavandi Mohammad Vakili Department of Chemistry School of SciencesFerdowsi University of MashhadMashhad 91775-1436Iran School of Chemistry Damghan University of Basic SciencesP.O.Box 36715-364DamghanIran

An efficient and easy method for one-pot three-component synthesis of l,3-disubstituted-3H-benzo[f]chromenes by the condensation of naphtol,aromatic aldehyde derivatives and phenylacetylene in the presence of ferric hydrogensulfate[Fe（HSO4）3], has been *** catalyst displayed high activity which afforded the corresponding 1,3-disubstituted-3H-benzo[f]chromenes in satisfying ***-substituted phenols were examined and the corresponding benzopyran derivatives were synthesized in moderate *** nature of the using catalyst made it reusable for further chemical reactions.

关键词： 1,3-Disubstituted-3H-benzo[f]chromenes Ferric hydrogensulfate One-pot synthesis Naphtopyran Benzopyran

Effects of Wind Turbines Equipped with Doubly-fed Induction Generators on Distance Protection

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电力系统自动化 2012年第8期36卷 128-131页

作者： hossein Kazemi KAREGAR Maryam KHODDAM Faculty of Electrical &Computer Engineering Shahid Beheshti University

Nowadays wind energy is the fastest growing renewable energy resource in the *** problems of integrating wind farms are caused by changes of wind speed during a ***,the behaviors of wind turbines equipped with doubly-fed induction generators differ fundamentally from synchronous ***,more considerations are needed to analyze the performances of the distance protection *** protection of a wind farm with distance relay is *** changing the conditions of the wind farm,the characteristics of the distance relay are studied.

关键词：距离保护双馈异步发电机风力发电机组配备可再生能源资源双馈感应发电机距离继电器同步发电机

Study of relation between the gamma flux buildup factors and source geometry by M-C simulation

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Nuclear Science and Techniques 2017年第9期28卷 31-35页

作者： Ali Rasouli hossein Tavakoli-Anbaran Faculty of Physics Shahrood University of Technology

This paper is to achieve a gamma-ray source with the lowest rate of buildup factor, which is of great importance in medical, industrial and agricultural *** flux buildup factor of gamma rays is calculated by the MCNP code for point, linear, surface and volume sources with shield layers of lead, iron and aluminum. The results show that for the high Z shielding material, the flux buildup factor of coaxial cylindrical sources is the lowest(1.6–2.3)of all sources, while for low Z shielding materials, the coaxial disk surface sources have smaller buildup factor(1.45–1.6).

关键词：通量几何模拟增强因子 γ射线源农业科学 MCNP 伽马射线

Nonalcoholic fatty liver disease in developing countries

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World Journal of Gastroenterology 2005年第24期11卷 3808-3809页

作者： hossein Bahrami Department of Epidemiology

TO THE EDITORNonalcoholic fatty liver disease (NAFLD) is an increasingly known medical entity with high prevalence, about 1 0 to 24 percent in general population and up to 74% in obese population[1]. The prevalence of the disease is expected to increase worldwide, as we are encountering the global obesity epidemic and the trend in developing countries toward the Western lifestyles. However, it looks that there are some differences between the demographic and epidemiologic features of NAFLD in developing and developed countries.

关键词： Nonalcoholic fatty liver Developing countries

Feasibility of using wind turbines for renewable hydrogen production in Firuzkuh, Iran

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Frontiers in Energy 2019年第3期13卷 494-505页

作者： Ali MOSTAFAEIPOUR Mojtaba QOLIPOUR hossein GOUDARZI Industrial Engineering Department Yazd UniversityYazd 89158-18411Iran School of Architecture and Environmental Design Iran University of Science and TechnologyTehran 16846-13114Iran

The present study was conducted with the objective of evaluating several proposed turbines from 25 kW to 1.65 MW in order to select the appropriate turbine for electricity and hydrogen production in Firuzkuh area using the decision making trial and evaluation (DEMATEL) and data envelopment analysis (DEA) methods. Initially, five important factors in selection of the best wind turbine for wind farm construction were determined using the DEMATEL technique. Then, technical-economic feasibility was performed for each of the eight proposed turbines using the HOMER software, and the performance score for each proposed wind turbine was obtained. The results show that the GE 1.5sl model wind turbine is suitable for wind farm construction. The turbine can generate 5515.325 MW of electricity annually, which is equivalent to $ 1103065. The average annual hydrogen production would be 1014 kg for Firuzkuh by using the GE 1.5sl model turbine.

关键词： wind turbine hydrogen production HOMER software decision making trial and evaluation (DEMA丒 TEL) data envelopment analysis (DEA) Firuzkuh

Full Polysaccharide Crosslinked-chitosan and Silver Nano Composites, for Use as an Antibacterial Membrane

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Chinese Journal of Polymer Science 2016年第8期34卷 949-964页

作者： hossein Ghasemzadeh Mahdieh Sheikhahmadi Fatemeh Nasrollah Department of chemistry Imam Khomeini International University

Full polysaccharide crosslinked-chitosan membranes were prepared by crosslinking of chitosan with chitosan dialdehyde followed by reduction with sodium borohydride. Partially oxidized chitosan, generated from periodate oxidation of chitosan, was used as a crosslinker. The modulus values and elongation at break were increased with increasing the crosslinker weight ratio. The rheological measurements showed that depolymerization of chitosan can take place rapidly in the presence of the oxidizing agent. The weight reduction of crosslinked-chitosan membrane after 12 h, at pH = 4 and pH = 2 was found to be 85.0% and 90.0%, respectively. The structure of the crosslinked-chitosan and the silver nanocomposite were confirmed by FTIR spectroscopy, scanning electron microscopy （SEM）, and thermogravimetric analysis （TGA）. Transmission electron microscopy （TEM） reveals the presence of well-separated Ag nanoparticles with diameters in the range of 4-10 nm. The silver ion loading increases with increasing the silver ion concentration, and decreasing the crosslink density. The MBC/MIC ratio of 2.0, 2.0, and 1.0 was achieved for E. coli, S. aureus, and P. aeruginosa, respectively.

关键词： Silver nanocomposites Chitosan Crosslinking Antibacterial effects.

STUDYING THE ABRASION BEHAVIOR OF RUBBERY MATERIALS WITH COMBINED DESIGN OF EXPERIMENT-ARTIFICIAL NEURAL NETWORK

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Chinese Journal of Polymer Science 2012年第4期30卷 520-529页

作者： Mehdi Shiva hossein Atashi Mahtab Hassanpourfard Research and Development Department ofKavir Tire Company.P.O.Box 518.Birjand Iran Department of Chemical Engineering Sistan and Baluchestan UniversityP.O.Box 98-164161ZahedanIran Departmen ofChemical Engineering Amirkabir University of TechnologyTehranlran

In this study, an application of artificial neural network （ANN） has been presented in modeling and studying the effect of compounding variables on abrasion behavior of rubber formulations. Three case studies were carried out in which the experiment data were collected according to classical response surface designs. Besides developing the ANN models, we developed response surface methodology （RSM） to confirm the ANN predictions. A simple relation was employed for determination of relative importance of each variable according to ANN models. It was shown through these case studies that ANN models delivered very good data fitting and their simulating curves could help the researchers to better understand the abrasion behavior.

关键词： Abrasion Feed forward neural networks Rubber compounding Central composite design.

Experimental investigation and adaptive neural fuzzy inference system prediction of copper recovery from flotation tailings by acid leaching in a batch agitated tank

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 538-546页

作者： Jalil Pazhoohan hossein Beiki Morteza EsfANDyari Department of Chemical Engineering Quchan University of Technology Department of chemical engineering University of Bojnord

The potential of copper recovery from flotation tailings was experimentally investigated using a laboratory-mixing tank. The experiments were performed with solid weight percentages of 30 wt%, 35 wt%, 40 wt% and 45 wt% in water. The measurements revealed that adding sulfuric acid all at once to the tank rapidly increased the efficiency of the leaching process, which was attributed to the rapid change in the acid concentration. The rate of iron dissolution from tailings was less than when the acid was added gradually. The sample with 40 wt% solid is recommended as an appropriate feed for the recovery of copper. The adaptive neural fuzzy system(ANFIS) was also used to predict the copper recovery from flotation tailings. The back-propagation algorithm and least squares method were applied for the training of ANFIS. The validation data was also applied to evaluate the performance of these models. Simulation results revealed that the testing results from these models were in good agreement with the experimental data.

关键词： flotation tailings leaching copper environments adaptive neural fuzzy inference system

Synthesis and Characterization of Soluble Polyester Based on Calixarene Dicarboxylic Acid with Tertiary Butyl Pendant Groups

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Chinese Journal of Polymer Science 2014年第5期32卷 551-557页

作者： hossein Mighani Hamed Tashakkorian Moein Mighani Faculty of Chemistry Golestan University Faculty of Chemistry Mazandaran University Department of Chemical Engineering Noshirvani University of Technology

A series of new polycalixesters （PCES） were synthesized by polyesterification of calixarene dicarboxylic acid derivatives having tertiary butyl pendant groups at the upper rim using five different diols. All polyesters were readily soluble in polar solvents such as NMP （N-methylpyrrolidone）, DMF （dimethylformamide）, DMSO （dimethylsulfoxide）, pyridine, THF （tetrahydrofurane）, HMPA （hexamethylenephosphoramide） and DMAC （dimethylacetamide）. The PCES were also partially soluble in TCE （tetrachloroethane） and ethanol and they were unsoluble in aceton. The glass transition temperatures of polyesters were between 80-184 ℃, the crystallinity temperatures of polyesters were between 130-212 ℃ and the melting temperatures of polyesters were between 185-234 ℃, as determined by differential scanning calorimeter （DSC）. The inherent viscosities of polyesters were obtained from 0.55 dL/mg to 0.61 dL/mg. The temperatures at 10% weight loss of polyesters ranged from 182 ℃ to 237 ℃. The temperatures at 25% weight loss of polyesters ranged from 258 ℃ to 331 ℃. The half weight loss （50%） temperatures of polyesters were among 315 ℃ to 371 ℃ and the char yields at 600 ℃ were determined within 13% to 22.3% in N2 atmosphere, as determined by thermo gravimetric analysis （TGA）. The polyester, PES3, has the higher melting point （234 ℃） and higher inherent viscosity （molecular weight） than the other polyesters.

关键词： Calixarene Polyester Thermal stability TGA DSC.