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Sulfamic acid:An efficient,cost-effective and green catalyst for crossed-aldol condensation of ketones with aromatic aldehydes under solvent-free

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Chinese Chemical Letters 2011年第9期22卷 1029-1032页

作者： amin Rostami Firoz Ahmad-Jangi Department of Chemistry Faculty of ScienceUniversity of Kurdistan

Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid （SA） to afford the corresponding α,β-unsaturated aldol products under solvent-free conditions... 详细信息

关键词： Aldehydes Ketones Crossed-aldol condensation β-Unsaturated aldol Catalyst Sulfamic acid

Experimental and numerical study of the blast wave decrease using sandwich panel by granular materials core

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Defence Technology（防务技术） 2021年第5期17卷 1660-1670页

作者： Masoud Rahmani Alireza Naddaf Oskouei amin Moslemi Petrudi Department of Mechanical Engineering IHU UniversityTehranIran Department of Mechanical Engineering Tehran UniversityTehranIran

Among the intrinsic properties of some materials,e.g.,foams,porous materials,and granular materials,are their ability to mitigate shock *** paper investigated shock wave mitigation by a sandwich panel with a granular *** simulations and experimental tests were performed using Autodyn hydro-code software and a shock tube,*** smoothed particle hydrodynamics(SPH)method was used to model granular *** and pumice,whose properties were determined by several compression tests,were used as granular materials in the sandwich panel *** granular materials possess many mechanisms,including compacting(e.g.,sawdust)and crushing(e.g.,pumice)that mitigate shock/blast *** results indicated the ineffectiveness of using a core with low thickness,yet it was demonstrated to be effective with high ***-thickness pumice yielded better results for wave *** use of these materials with a core with appropriate core reduces up to 88%of the shock *** results of the experiments and numerical simulations were compared,suggesting a good agreement between the *** indicates the accuracy of simulation and the ability of the SPH method to modeling granular material under shock *** effects of grain size and the coefficient of friction between grains have also been investigated using simulation,implying that increasing the grain size and coefficient of friction between grains both reduce overpressure.

关键词： Granular materials Shock tube Blast wave Numerical simulations

Influence of shielding gas on the mechanical and metallurgical properties of DP-GMA-welded 5083-H321 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1416-1426页

作者： amin Reza Koushki Massoud Goodarzi Moslem Paidar Department of Metallurgy and Materials Engineering Iran University of Science and technology Department of Materials Engineering South Tehran Branch Islamic Azad University

In the present research, 6-mm-thick 5083-H321 aluminum alloy was joined by the double-pulsed gas metal arc welding （DP-GMAW） process. The objective was to investigate the influence of the shielding gas composition on the microstructure and properties of GMA welds. A macrostructural study indicated that the addition of nitrogen and oxygen to the argon shielding gas resulted in better weld penetration. Furthermore, the tensile strength and bending strength of the welds were improved when oxygen and nitrogen （at concentrations as high as approximately 0. 1vol%） were added to the shielding gas; however, these properties were adversely affected when the oxygen and nitrogen contents were increased further. This behavior was attributed to the formation of excessive brown and black oxide films on the bead surface, the formation of intermetallic compounds in the weld metal, and the formation of thicker oxide layers on the bead surface with increasing nitrogen and oxygen contents in the argon-based shielding gas. Analysis by energy-dispersive X-ray spectroscopy revealed that most of these compounds are nitrides or oxides.

关键词： aluminum alloys gas metal arc welding shielding gas mechanical properties metallurgical properties

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

Structure of ADAFs in a general large-scale B-field:the role of wind and thermal conduction

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Research in Astronomy and Astrophysics 2013年第1期13卷 87-98页

作者： amin Mosallanezhad Mehdi Khajavi Shahram Abbassi Center for Excellence in Astronomy & Astrophysics (CEAA-RIAAM) School of Physics Damghan University Department of Physics School of SciencesFerdowsi University of Mashhad School of Astronomy Institute for Research in Fundamental Sciences

We have explored the structure of a hot flow bathed in a general large-scale magnetic field. The importance of outflow and thermal conduction on the self-similar structure of a hot accretion flow has been investigated. We consider the additional 2 2 2 magnetic parameters are the Alfv6n sound speeds in three directions of cylindrical coordinates. In comparison to the accretion disk without winds, our results show that the radial and rotational velocities of the disk become faster, but the disk becomes cooler because of the angular momentum and energy flux which are taken away by the winds. Moreover, thermal conduction opposes the effect of winds and not only decreases the rotational velocity but also in- creases the radial velocity as well as the sound speed of the disk. In addition, we study the effect of the global magnetic field on the structure of the disk. Our numerical re- suits show that all the components of a magnetic field can be important and they have a considerable effect on velocities and vertical structure of the disk.

关键词： accretion: accretion flow -- wind: outflow -- thermal conduction

Comparative life table analysis of Tetranychus urticae （Acari Tetranychidae） on 14 soybean genotypes

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Insect Science 2011年第5期18卷 541-553页

作者： amin Sedaratian Yaghoub Fathipour Saeid Moharramipour Department of Entomology Faculty of Agriculture Tarbiat Modares University Tehran Iran

The life table parameters of two-spotted spider mite （TSSM）, Tetranychus urticae Koch, on 14 soybean genotypes （Sari, Sahar, Tellar, Zane, Ks3494, LI7, Dpx, 032, 033, Clark, Hill, 127, Tms and Williams） were evaluated at 28 ±1℃, 65% ± 5% RH and a photoperiod of 16 ： 8 h L ： D. The survivorship data （lx） of adult females were fitted to the Weibull frequency distribution model in all genotypes tested. Based on the Weibull parameters, the survival curve was type I on all genotypes, which indicated that the mortality mostly occurred in old individuals. Furthermore, two mathematical models （Analytis and Enkegaard） were fitted to age-specific fecundity data （mx）. The highest intrinsic rate of increase （rm） was recorded on L17 （0.392） and the lowest values of this parameter were obtained on Tms （0.233）, Hill （0.236）, 032 （0.236）, 127 （0.237） and Clark （0.240）. In addition, net reproductive rate （R0） and finite rate of increase （λ） of the TSSM had the highest value on L17 as 45.521 and 1.475, respectively. The lowest values of these parameters were recorded on Tms as 12.149 and 1.258, respectively. Doubling time （DT） varied significantly on different genotypes and the shortest and longest values of this period were obtained on L17 and 032, respectively. Our findings revealed that Tms, Hill, 032, 127 and Clark were less suitable genotypes, suggesting that they are more resistant to the TSSM than the other genotypes.

关键词： fecundity life table parameters resistance soybean two-spotted spider mite

Co-optimization of carbon dioxide storage and enhanced oil recovery in oil reservoirs using a multi-objective genetic algorithm(NSGA-Ⅱ)

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Petroleum Science 2014年第3期11卷 460-468页

作者： SAFARZADEH Mohammad amin MOTAHHARI Seyyed Mahdia Research Institute of Petroleum Industry

Climate researchers have observed that the carbon dioxide （CO2） concentration in the atmosphere have been growing significantly over the past century. CO2 from energy represents about 75% of the greenhouse gas （GHG） emissions for Annex B （Developed） countries, and over 60% of global emissions. Because of impermeable cap rocks hydrocarbon reservoirs are able to sequester CO〉 In addition, due to high-demand for oil worldwide, injection of CO2 is a useful way to enhance oil production. Hence, applying an efficient method to co-optimize CO2 storage and oil production is vital. Lack of suitable optimization techniques in the past led most multi-objective optimization problems to be tackled in the same way as a single objective optimization issue. However, there are some basic differences between the multi and single objective optimization methods. In this study, by using a non- dominated sorting genetic algorithm （NSGA-II） for an oil reservoir, some appropriate scenarios are proposed based on simultaneous gas storage and enhanced oil recovery optimization. The advantages of this method allow us to amend production scenarios after implementing the optimization process, by regarding the variation of economic parameters such as oil price and CO2 tax. This leads to reduced risks and time duration of making new decisions based on upcoming situations.

关键词： Greenhouse gas emission carbon dioxide enhanced oil recovery multi-objective optimization decision making

A Comprehensive Review on Multi-Dimensional Heat Conduction of Multi-Layer and Composite Structures:Analytical Solutions

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Journal of Thermal Science 2021年第6期30卷 1875-1907页

作者： AMIRI DELOUEI amin EMAMIAN amin SAJJADI Hasan ATASHAFROOZ Meysam LI Yueming WANG Lian-Ping JING Dengwei XIE Gongnan Department of Mechanical Engineering University of BojnordBojnordIran Mechanical Engineering Department Shahrood University of TechnologyShahroodIran Department of Mechanical Engineering Siijan University of TechnologySiijanIran School of Aerospace Engineering Xi’an Jiaotong UniversityXi’an 710049China Guangdong Provincial Key Laboratory of Turbulence Research and Applications Center for Complex Flows and Soft Matter Research and Department of Mechanics and Aerospace EngineeringSouthern University of Science and TechnologyShenzhen 518055China Department of Mechanical Engineering University of DelawareNewarkDelaware19711USA International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China Department of Mechanical and Power Engineering Northwestern Polytechnical UniversityXi'an 710072China

Heat conduction in multi-layer and composite materials is one of the fundamental heat transfer problems in many industrial *** to different materials types,interface conditions,and various geometries of these laminates,the heat conduction mechanism is more complicated than that of one-layer isotropic *** solutions are the best ways to study and understand such problems in *** this study,different existing analytical solutions for heat conduction in multi-layer and composite materials are reviewed and classified in rectangular,cylindrical,spherical,and conical *** boundary conditions,internal heat source,and thermal contact resistance as the most critical parameters in the solution complexity investigated in the literature,are discussed and summarized in different *** types of multi-layer structures such as isotropic,anisotropic,orthotropic,and reinforced laminates are included in this *** is found that although more than half a century has passed since the beginning of the research on heat transfer in multi-layer composites,new researches that can help with a better understanding in this area are still being *** challenges and shortcomings in this area are also discussed to guide future researches.

关键词： multi-dimensional heat conduction composite laminates multi-layer structures analytical solutions interface contact resistance

Dual PPAR delta/gamma agonist offer therapeutic potential for Alzheimer's disease

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Neural Regeneration Research 2024年第6期19卷 1175-1176页

作者： Ian Steinke Meenakshi Singh Rajesh amin Department of Drug Discovery and Development Auburn UniversityAuburn AlabamaALUSA

The increasing incidence of Alzheimer's disease(AD)in the aging population,indicates the critical need for the development of novel targeted molecular therapies for ameliorating AD ***,clinical and preclinical evidence demonstrates that peroxisomal proliferator activating receptors(PPAR)agonists regulate energy and lipid homeostasis in models of diabetes,as well as improve spatial memory in animal models of AD(Khan et al.,2019).

关键词： Alzheimer clinical homeostasis