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Chinese Chemical Letters 2013年第10期24卷 901-903页

作者： Razieh Doostmohammadi Malek Taher Maghsoodlou Nourallah Hazeri sayyed mostafa habibi-khorassani Department of Chemistry Faculty of ScienceThe University of Sistan and Baluchestan

A facile one-pot synthesis of 3,4,5-substituted furan-2（5H）-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using t... 详细信息

关键词： 3 4 5-Substituted furan-2(5H)-one Aniline derivative Dialkyl acetylenedicarhoxylate Aromatic aldehyde Tetra-n-butylammonium bisulfate

An efficient synthesis of 2,2′-arylmethylene bis-(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1,8-dioxooctahydroxanthenes using ZnO and ZnO-acetyl chloride

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Chinese Chemical Letters 2010年第6期21卷 686-689页

作者： Malek Taher Maghsoodlou sayyed mostafa habibi-khorassani Zahra Shahkarami Nariman Maleki Mohsen Rostamizadeh Department of Chemistry The University of Sistan and BaluchestanP.O.Box 98135-674ZahedanIran

2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chlo... 详细信息

关键词： ZnO ZnO-acetyl chloride Dimedone Aldehyde 1 8-Dioxooctahydroxanthene 2 2'-Arylmethylene bis(3-hydroxy-5 5-dimethyl-2-cyclohexene-1-one)

Entirely green protocol for the synthesis of β-aminoketones using saccharose as a homogenous catalyst

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Chinese Chemical Letters 2013年第5期24卷 411-414页

作者： Mir Rasul Mousavi Nourallah Hazeri Malek Taher Maghsoodlou Sajjad Salahi sayyed mostafa habibi-khorassani Department of Chemistry Faculty of ScienceUniversity of Sistan and Baluchestan

Saccharose was applied as an efficient and homogenous catalyst for a one-pot,three-component Mannich reaction for the formation ofβ-aminoketones from aromatic aldehydes,anilines,and acetophenone at ambient temperature in excellent *** protocol has the following advantages： mild conditions,high yields,clean reaction profiles,operational simplicity,and environmentally benign and simple work-up procedures.

关键词： Saccharose β-Amino carbonyl compounds Mannich reaction Three-component reaction

One-pot five-component synthesis of highly functionalized piperidines using oxalic acid dihydrate as a homogenous catalyst

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Chinese Chemical Letters 2012年第5期23卷 569-572页

作者： Seyed Sajad Sajadikhah Malek Taher Maghsoodlou Nourallah Hazeri sayyed mostafa habibi-khorassani Anthony C.Willis Department of Chemistry The University of Sistan and BaluchestanP.O.Box 98135-674ZahedanIran Research School of Chemistry The Australian National UniversityCanberraACT 0200Australia

An efficient green protocol is described for the preparation of highly functionalized piperidines via a one-pot five-component reaction between aromatic aldehydes,anilines andβ-ketoesters in the presence of oxalic acid dihydrate as catalyst in ethanol at ambient *** structure as well as the relative stereochemistry of these compounds was confirmed by single X-ray crystallographic analysis.

关键词： Piperidine Heterocycle Homogeneous catalyst Oxalic acid dihydrate Multi-component reaction

果糖催化合成四氢苯并[b]吡喃衍生物:动力学和机理研究(英文)

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催化学报 2015年第5期36卷 757-763页

作者： sayyedeh Shadfar Pourpanah sayyed mostafa habibi-khorassani Mehdi Shahraki Department of Chemistry University of Sistan and Baluchestan

Fructose was used as an efficient catalyst for three-component condensation reactions of aryl aldehydes,malononitrile,and dimedone in a mixture of EtOH and H_2O as green *** advantages of this method are a short reaction time,high yields,low cost,easy accesses,and simple *** mechanism of the synthesis of a derivative of 4H-tetrahydrobenzo[b]pyran was clarified using spectroscopic kinetic *** activation energy(Ea=65.34 kJ/mol)and related kinetic parameters(ΔG=69.14 kJ/mol,ΔS=20.99 J/(mol·K),andΔH=62.89 kJ/mol)were calculated,based on the effects of temperature,concentration,and *** first step in the proposed mechanism was identified as the rate-determining step(k1),based on the steady-state approximation.

关键词：吡喃衍生物动力学方法四氢苯并催化合成果糖机理绿色溶剂缩合反应

Comparison of effective parameters for copper powder production via electrorefining and electrowinning cells and improvement using DOE methods

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 731-740页

作者： Ebrahim Akbarzadeh sayyed Esmaeil Shakib Department of Materials Science and Metallurgical Engineering Shahid Bahonar University of Kerman

The influences of cupric ion concentration （5-35 g/L）,current density （500-2000 A/m2）,circulation rate of the electrolyte solution （15-120 mL/min）,and temperature （25-60℃） on the physical and chemical properties of copper powders obtained in electrolysis cells were *** industrial processes,electrorefining （ER） cells with a synthetic electrolyte and electrowinning （EW） cells with an original solution of coppermineral leaching,were utilized to produce copper ***,the statistical full factorial method of design of experiments （DOE） was employed to investigate the interaction or the main effects of *** results show that increasing the copper concentration and temperature can increase the grain size,apparent density,and electrical energy *** the other hand,increasing the current density and circulation rate of the electrolyte can decrease *** production process is optimized via DOE to control the interactive and main effects to produce copper powders with favorable properties.

关键词： copper powders electrorefining electrowinning grain size apparent density

Model for increased efficiency of CIGS solar cells by a stepped distribution of carrier density and Ga in the absorber layer

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1533-1541页

作者： SHARBATI Samaneh KESHMIRI sayyed-Hossein Department of Electrical Engineering Ferdowsi University of Mashhad

In this paper, several structures for multilayer Cu(In1-xGax) Se2 (CIGS) thin film solar cells are proposed to achieve high conversion efficiency. All of the modeling and simulations were based on the actual data of experimentally produced CIGS cells reported in the literature. In standard CIGS cells with a single absorber layer, the effects of acceptor density and Ga content on device performance were studied, and then optimized for maximum conversion efficiency. The same procedure was performed for cells with two and three sectioned CIGS absorber layers in which Cu and/or Ga contents were varied within each consecutive section. This produces an internal additional electric field within the absorber layer, which resulted in an increase in carrier collection for longer wavelength photons, and hence, improvement in the conversion efficiency of the cell. An increase of approximately 3% in efficiency is predicted for cells with two layer absorbers. For multilayer cells in which Cu and Ga distribution were stepped simultaneously, the improvement could be approximately 3.5%. This improvement is due to; enhanced carrier collection for longer-wavelength photons, and reduced recombination at the heterojunction and back regions of the cell. These results are confirmed by the physics of the cells.

关键词： Cu (In Ga)Se2 (CIGS) multilayer thin film solar cell quantum efficiency

Flood basalt hosted palaeosols:Potential palaeoclimatic indicators of global climate change

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Geoscience Frontiers 2014年第6期5卷 791-799页

作者： M.R.G.sayyed Department of Geology Poona College (University of Pune)CampPune 411 001MaharashtraIndia

Since continental sediments （in addition to the marine geological record） offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the ~lobe havin~ different ages.

关键词： Continental flood basalts Palaeosols Weathering Palaeoclimates Global change

Water Consumption of a Six-Year-Old River Red Gum Plantation in the Southern Zagros Mountains,Iran

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Journal of Mountain Science 2007年第2期4卷 136-145页

作者： Masoud EDRAKI sayyed Ahang KOWSAR Department of Primary Industries Sunraysia Horticultural Centre PO Box 905Mildura Victoria Australia Fats Research Center for Agriculture and Natural Resources P.O. Box 71365-458 Shiraz LR. Iran

Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum （Eucalyptus camaldulensis Dehnh.） plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system in Iran＇s southern Zagros Mountains, was studied during a 7-month period. A neutron moisture probe was used to monitor soil water changes in the root zone. Soil water depletion following rapid drainage for blocks receiving relatively high, medium and low volumes of foodwater were 809.6, 312.4, and 203.1 mm, respectively, for a 150-day period. Soil water potential during most of the study period was below -1.5 MPa. This study proves that river red gum in not a suitable species for desertification control where water conservation is of vital importance. Flood irrigation of trees on 8 Aug. 1991 provided the opportunity to throw doubt upon the claim of summer dormancy of river red gum.

关键词： Water consumption Eucalyptus camaldulensis desertification control Iran

Bayesian Regularization Neural Networks for Prediction of Austenite Formation Temperatures(A_(c1) and A_(c3))

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Journal of Iron and Steel Research International 2014年第2期21卷 246-251页

作者： Masoud RAKHSHKHORSHID sayyed-Amin TEIMOURI SENDESI Department of Mechanical Engineering Birjand University of Technology Department of Mechanical Engineering Roudbar BranchIslamic Azad University

A neural network with a feed forward topology and Bayesian regularization training algorithm is used to predict the austenite formation temperatures （At1 and A13） by considering the percentage of alloying elements in chemical composition of steel. The data base used here involves a large variety of different steel types such as struc- tural steels, stainless steels, rail steels, spring steels, high temperature creep resisting steels and tool steels. Scatter diagrams and mean relative error （MRE） statistical criteria are used to compare the performance of developed neural network with the results of Andrew% empirical equations and a feed forward neural network with ＂gradient descent with momentum＂ training algorithm. The results showed that Bayesian regularization neural network has the best performance. Also, due to the satisfactory results of the developed neural network, it was used to investigate the effect of the chemical composition on Ac1 and At3 temperatures. Results are in accordance with materials science theories.

关键词： Bayesian regularization neural network steel chemical composition Ac1 Ae3