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排序方式: 共有236条查询结果,搜索用时 15 毫秒
11.
Ali Reza Kiasat Foad Kazemi Mehdi Fallah Mehr Jardi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1841-1844
A simple and efficient method for the conversion of various oxiranes to the corresponding thiiranes using thiourea under solvent free conditions is described. 相似文献
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M. Shayganmanesh M.H. Daemi Zh. Osgoui S. Radmard S.Sh. Kazemi 《Optics & Laser Technology》2012,44(7):2292-2296
Two different experimental methods for disk characterization in thin disk lasers are investigated in this paper. First method is based on the stability regions in optical resonator and the second method is based on using an expanded probe beam. Both of the mentioned techniques are used to determine the thermal lensing effects in high power thin disk laser. The results of the experiments are presented and analyzed. Also the advantages and disadvantages of each method are explained. 相似文献
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Pezhman Kazemi Mohammad Peydayesh Alireza Bandegi Toraj Mohammadi Omid Bakhtiari 《Chemical Papers》2013,67(7):722-729
An experimental study on the pertraction of methylene blue (MB) through a supported liquid membrane (SLM) using a mixture of mono-(2-etylhexyl) ester of phosphoric acid (M2EHPA) and bis-(2-etylhexyl) ester of phosphoric acid (D2EHPA) and sesame oil as the liquid membrane (LM) was performed. Parameters affecting the pertraction of MB such as initial MB concentration, carrier concentration, feed phase pH, and stripping phase concentration were analyzed. Optimal experimental conditions for MB pertraction (permeability of 5.63 × 10?6) were obtained after a 7 h separation with the MB concentration in the feed phase of 80 mg L?1, D2EHPA/M2EHPA concentration in membrane phase of 40 vol. %, feed pH of 6, and acetic acid concentration in the stripping phase of 0.4 mol L?1. Kinetics of transport and stability of the SLM system were also studied and the mass transfer coefficient for this system was evaluated. Scanning electron microscopy (SEM) was used to morphologically characterize the membrane surface. 相似文献
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Amirhossein Saali Mohammad Shokouhi Hossein Sakhaeinia Nima Kazemi 《Journal of solution chemistry》2020,49(3):383-404
The thermodynamic consistency test of solubility P–T–x data for binary mixtures including carbon dioxide (CO2) + a room temperature ionic liquid has been investigated. Experimental solubility data taken from the open literature for 32 binary mixtures of CO2/RTILs contains 80 isotherms. The applied consistency test is based on the fundamental Gibbs–Duhem equation with use of the generic Redlich–Kwong (GRK) equation of state (EoS) coupled with the van der Waals–Berthelot (GRK/vdWB) mixing rule. The optimum parameters were obtained by minimizing the summation of per cent relative deviations between modeled and experimental data, based on the bubble pressure algorithm. Modeling was found acceptable for all isotherms, which demonstrated the usability of the GRK equation of state. Results of the thermodynamic consistency test showed that 36 of the isothermal data sets were thermodynamically consistent, 37 were not fully consistent, 6 were thermodynamically inconsistent and only one data set was found to need another model. 相似文献
17.
Conventional DEA models have been introduced to deal with non-negative data. In the real world, in some occasions, we have outputs and/or inputs, which can take negative data. In DEA literature some approaches have been presented for evaluating performance of units, which operate with negative data. In this paper, firstly, we give a brief review of these works, then we present a new additive based approach in this framework. The proposed model is designed to provide a target with non-negative value associated with negative components for each observed unit, failed by other methods. An empirical application in banking is then used to show the applicability of the proposed method and make a comparison with the other approaches in the literature. 相似文献
18.
A palladium-catalyzed dehydrogenative acylation of indoles using easily accessible aldehydes as the acyl source is described. This reaction provides a new approach for the synthesis of 3-acylindoles. 相似文献
19.
Electrochemical Determination of Dextromethorphan on Reduced Graphene Oxide Modified Screen‐Printed Electrode after Electromembrane Extraction 下载免费PDF全文
Ali Reza Fakhari Mohammad Hossein Koruni Hamid Ahmar Abolfath Shahsavani Siyavash Kazemi Movahed 《Electroanalysis》2014,26(3):521-529
In this paper, electromembrane extraction coupled with differential pulse voltammetry (DPV) on a reduced graphene oxide modified screen‐printed carbon electrode (RGO‐SPCE) for the determination of dextromethorphan (DXM) in urine and plasma has been described. DXM migrated from 4 mL of a donor phase across a thin layer of 2‐nitrophenyl octyl ether (NPOE) immobilized in the pores of a porous hollow fiber, into a 20 µL acceptor phase (HCl) present inside the lumen of the fiber. Then, 15 µL of a 0.1 M NaOH solution was added to the acceptor phase and the mixture was analyzed using DPV. 相似文献
20.
Foad Kazemi Ali Reza Kiasat 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1333-1337
Epoxids are efficiently converted to the corresponding thiiranes by ammonium thiocyanate (NH 4 SCN) in the presence of catalytic amounts of oxalic acid with excellent isolated yields under mild and nonaqueous reaction conditions. This conversion performed under both conventional heating and microwave conditions. Distinct rate enhancement is observed under microwave irradiation. 相似文献