检索结果-南通市图书馆

Journal of Magnesium and Alloys 2019年第1期7卷 80-89页

作者： Mohammad Janbozorgi Kimia karimi Taheri ali karimi Taheri Department of Materials Science and Engineering Sharif University of TechnologyAzadi Ave.TehranIran School of Medicine Shahid Beheshti University of Medical ScienceTehranIran

During the recent years,some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical *** this work,the Mg-2Zn-1Gd-1Ca(wt%)alloy as a new metallic bio-material was produced by the casting process followed by the heat *** samples of the alloy were solution treated at temperatures of 500,550,and 600°C and then quench aged at temperatures of 125,150,and 175°*** results of SEM-EDS examinations indicated that the alloy microstructure consists ofα-Mg matrix and the Ca_(2)Mg_(6)Zn_(3)and Mg_(3)Gd_(2)Zn_(3)secondary *** regard to the results of Vickers hardness test,the temperatures of 500°C and 150°C were selected as the optimum solutionizing and aging temperatures,***,the dissolution of casting precipitates and production of lattice distortion occurring after the solution treatment led to the reduction in ultimate shear strength up to 21%.But,the precipitation hardening and morphological changes taking place during the aging treatment improved the ultimate shear strength up to 32%.Furthermore,the results of electro-chemical and weight-loss measurements in a simulated body fluid indicated that the heat-treated alloy is a promising candidate for the Mg based alloys recently considered for the bio-medical applications.

关键词： Mg alloys Bio-medical applications Microstructural evolution Mechanical properties Corrosion resistance

RAPID AND FACILE SYNTHESIS OF ACYL AZIDES FROM ACYL HaliDES USING A POLYMER-SUPPORTED AZIDE ION UNDER HETEROGENEOUS CONDITIONS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2013年第7期31卷 1002-1010页

作者： Mohammad ali karimi Zarchi Saeed Barani Department of Chemistry College of SciencesYazd University

In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly（N-methyl-4- vinylpyridinium） azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.

关键词： Acyl azide Acyl halide Polymeric reagent Heterogeneous condition.

In vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract of Quercus brantii *** and subsequent fractions

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2016年第3期14卷 196-202页

作者： Mohammad-taghi Moradi ali karimi Somayeh alidadi Student's Research Committee Shahrekord University of Medical Science Medical Plants Research Center Shahrekord University of Medical Science Clinical Biochemistry Research Center Shahrekord University of Medical Science

Cancer cell resistance to widely used chemotherapeutic agents is gradually developed. Natural products, mainly isolated from medicinal plants, have been considered as valuable sources for herbal anticancer drugs. The present study aimed to evaluate in vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract and four fractions of Q. brantii acorn. Crude ethyle alcohole extract of Q. brantii acorn was prepared and subjected to fractionation with different polarity. Subsequently, the extract and the fractions wereevaluated for their in vitro antiproliferative activity in two cancerous(Hela and AGS) and one normal(HDFs) cell lines using MTT [3-(4, 5-dimethylthiazol-2ol) 2, 5 diphenyltetrazoliumbromide] assay. To determine whether the cytotoxicity of these compounds involved the induction of apoptosis, Hela cells were treated with IC_(50) concentrations of test compounds, stained with both propidium iodide(PI) and Annexin V-fluorescein isothiocyanate(FITC), and analyzed by flow cytometry. In vitro cytotoxicity assay showed that the cell viability was significantly reduced in a dose-dependent manner following treatment with crude ethyle alcohole extract and Cholophorm and n-Butanol fractions. Based on the probit regression model, antiproliferative activities of crude ethyle alcohole extract, Cholophorm fraction, and n-Butanol fraction on Hela and AGS cells and HDFs cells were significantly different(P < 0.001). The results of flow cytometric analysis showed that crude ethyle alcohole extract and two fractions of Q. brantii acorn induced early apoptotic cell death. These findings suggest that crude ethyle alcohole extract and Cholophorm and n-Butanol fractions of Q. brantii acorn suppress the proliferation of cancer cells through induction of early apoptosis.

关键词： Quercus brantii Lindl Cancer Proliferation Apoptosis

Stripping voltammetric determination of Cd(Ⅱ)based on multiwalled carbon nanotube functionalized with 1-(2-pyridylazo)-2-naphthol

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第12期22卷 1469-1472页

作者： alireza Mohadesi Hadi Beitollahi Mohammad ali karimi Department of Chemistry Payame Noor UniversityTehran 19395-4697Iran Department of Chemistry Payame Noor University(PNU)P.O.Box 76175-559KermanIran Environmental Department Research Institute of Environmental SciencesInternational Center for SciencesHigh Technology and Environmental SciencesKermanIran Department of Chemistry & Nanoscience and Nanotechnology Research Laboratory(NNRL) Payame Noor University(PNU)SirjanIran

The present work has focused on the modification of multiwalled carbon nanotube with a ligand,l-（2-pyridylazo）-2-naphthol, and its potential application for the development of a new,simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd（Ⅱ）.The analytical curve for Cd（Ⅱ） ions covered the linear range varying from 0.8 up to 220.4μgL^（-1）.The limit of detection was found to be 0.1μgL^（-1）,while the relative standard deviation（RSD） at 50.0μgL^（-1） was 1.8%（n=5）.This modified electrode was successfully applied for determination of Cd（Ⅱ） in some water samples.

关键词： Multiwalled carbon nanotube 1-(2-Pyridylazo)-2-naphthol Cadmium(Ⅱ) Stripping voltammetry

Organo-silane compounds in medium density fiberboard:physical and mechanical properties

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2015年第2期26卷 495-500页

作者： Hamid Reza Taghiyari ali karimi Paridah Md.Tahir Wood Science & Technology Department Faculty of Civil EngineeringShahid Rajaee Teacher Training University Department of Wood and Paper Science & Technology Faculty of Natural ResourcesThe University of Tehran Laboratory of Biocomposite Technology Institute of Tropical Forestry & Forest Products (INTROP)University Putra Malaysia (UPM)

We studied the effects of nanoparticles of organo-silane（NOS） compounds in the size range of20–80 nm on physical and mechanical properties in medium density fiberboard,and used NOS at four consumption levels of 0,50,100,and 150 g kg-1dry wood *** of all treatments was kept constant at 0.67 g *** water-repellent property of organo-silane significantly reduced water absorption（WA） and thickness swelling but mechanical properties declined due to the reduced proportion of wood-fiber as organo-silane was added to the matrix：the compression ratio of MDF panels and the integrity among wood-fibers both declined,resulting in reduced mechanical *** recommend use of 50 g of NOS/kg wood-fiber to improve WA and thickness swelling while retaining acceptable mechanical properties.

关键词： Composite-board Medium-density fiberboard(MDF) Nanotechnology Physical and mechanical properties Water-repellant Organo-silane

Fischer-Tropsch synthesis over ruthenium-promoted Co/Al_2O_3 catalyst with different reduction procedures

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第5期19卷 503-508页

作者： ali karimi ali Nakhaei Pour Farshad Torabi Behnam Hatami Ahmad Tavasoli Mohammad Reza Alaei Mohammad Irani Research Institute of Petroleum Industry (RIPI) Gas Research Division

The effect of reduction procedure on catalyst properties, activity and products selectivity of ruthenium-promoted Co/γ-Al2O3 catalyst in Fischer-Tropsch synthesis （FTS） was investigated. Catalyst samples were reduced with different reduction gas compositions and passivated before being characterized by TPR and XRD techniques. Different activity and product selectivity analyses were also performed. These results showed that the catalyst dispersion, particle size, and the degree of reduction changed with different reduction gas compositions, which were resulted from the water partial pressures in reduction process that give varying degrees of interaction with the support. It has been suggested that the FTS activity of cobalt catalyst was directly dependent on the catalyst reducibility. A reduction gas with a molar ratio of H2Prle = 1 was used to prevent the formation of Co-support compound during catalyst reduction.

关键词： Fischer-Tropsch synthesis cobalt reducibility activity C5+ selectivity

Electrocatalytic oxidation of hydrazine with alizarin red S as a homogenous mediator on the glassy carbon electrode

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2010年第5期53卷 1194-1200页

作者： Mohammad Mazloum-Ardakani Roya Mazidi Mohammad Hossein Mashhadizadeh Parvanah Rahimi Mohammad ali karimi Department of Chemistry Faculty of ScienceYazd University Department of Chemistry Payam Noor UniversityArdakan Center Department of Chemistry Faculty of ScienceTarbiat Moalem University Department of Chemistry Faculty of SciencePayam Noor UniversitySirjan Center

Electro-catalytic oxidation and detection of hydrazine on a glassy carbon electrode,at pH 6.0,was studied by using alizarin red S as a homogeneous *** overall number of electrons involved in the catalytic oxidation of hydrazine and that involved in the rate-determining step were four and one,*** interfering effect of some cations,anions and organic compounds were *** current for this process varied linearly with the square root of the scan *** kinetic parameters,such as the electron transfer coefficient(α) and catalytic rate constant(k) ,were determined using cyclic voltammetry,linear sweep voltammetry and *** electro-catalytic response was optimized with regards to the pH,scan rate,hydrazine concentration and other variables.

关键词： alizarin red S hydrazine glassy carbon electrode electro-catalytic oxidation voltammetry

Synthesis and characterization of multiwall carbon nanotubes/alumina nanohybrid-supported cobalt catalyst in Fischer-Tropsch synthesis

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2013年第4期22卷 582-590页

作者： ali karimi Bahram Nasernejad ali Morad Rashidi Chemical Engineering Department Amir Kabir University of Technology Nanotechnology Research Center Research Institute of Petroleum Industry

Multiwall carbon nanotubes （MWNTs） and alumina are combined to give a new type of nanohybrid for Fisher-Tropsch synthesis （FTS） catalyst support. Alumina nano-particles （10 wt%） were introduced directly on functionalized MWNTs by a modified sol-gel method. Microstructure observations show that alumina particles were homogeneously dispersed on the inside and outside of modified MWNTs surfaces. 15 wt% cobalt loading catalysts were prepared with this nanohybrid and γ-alumina as a reference, using a sol-gel technique and wet impregnation method respectively. These catalysts were characterized by TEM, XRD, N2-adsorption, H2 chemisorption and TPR. The deposition of cobalt nanoparticles synthesized by sol-gel technique on the MWNTs nanohybrid shift the reduction peaks to a low temperature, indicating higher reducibility for uniform cobalt particles. Nanohybrid also aided in high dispersion of metal clusters and high stability and performance of catalyst. The proposed MWNTs nanohybrid-supported cobalt catalysts showed the improved FTS rate （gHc/（***））, CO conversion （%）, and water gas shift rate （WGS）（gcoz/（gcat.h）） of 0.012, 52, and 30E-3, respectively, as compared to those of 0.007, 25, and 18E-3, respectively, on the γ-alumina-supported cobalt catalysts with the same Co loading.

关键词： carbon nanotubes nanohybrid cobalt catalyst alumina FT synthesis sol-gel

Microstructural and mechanical properties assessment of transient liquid phase bonding of CoCuFeMnNi high entropy alloy

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2021年第10期31卷 3063-3074页

作者： Mohammad ali karimi Morteza SHAMANIAN Mohammad Hossein ENAYATI Department of Materials Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran

The transient liquid phase(TLP)bonding of CoCuFeMnNi high entropy alloy(HEA)was *** TLP bonding was performed using AWS BNi-2 interlayer at 1050℃ with the TLP bonding time of 20,60,180 and 240 *** effect of bonding time on the joint microstructure was characterized by SEM and *** results confirmed that complete isothermal solidification occurred approximately at 240 min of bonding *** samples bonded at 20,60 and 180 min,athermal solidification zone was formed in the bonding area which included Cr-rich boride and Mn3Si intermetallic *** all samples,theγsolid solution was formed in the isothermal solidification zone of the bonding *** evaluate the effect of TLP bonding time on mechanical properties of joints,the shear strength and micro-hardness of joints were *** results indicated a decrement of micro-hardness in the bonding zone and an increment of micro-hardness in the adjacent zone of *** minimum and maximum values of shear strength were 100 and 180 MPa for joints with the bonding time of 20 and 240 min,respectively.

关键词： high entropy alloy CoCuFeMnNi alloy transient liquid phase bonding bonding time solid solution isothermal solidification microstructure mechanical properties

Coordination of Synergetic Excitation Controller and SVC Damping Controller Using Particle Swarm Optimization

在线全文

学校读者我要写书评

暂无评论

Journal of Energy and Power Engineering 2012年第8期6卷 1292-1300页

作者： Taoridi Ademoye ali Feliachi ali karimi Advanced Power & Electric Research Center West Virginia University Morgantown WV 26506-6109 USA Open Systems International (OSI) 4101 Arrowhead Drive Medina MN 55340-9457 USA

This paper addresses the enhancement of power system stability by simultaneous tuning of synergetic excitation damping controller and SVC （static var compensator）-based damping controllers. Each machine or generator is considered as a subsystem and its interaction with the remaining part of the system, the SVC inclusive, is modeled as a quadratic function of the active power delivered by the generator. Stable manifold is constructed for each excitation controller and based on that, an effective damping controller is derived. A lead-lag compensator is employed as a supplementary controller for the SVC. PSO （particle swarm optimization） algorithm is effectively utilized to simultaneously tune the parameters for the excitation damping controller（s） and the SVC supplementary controller. The coordination of the controllers effectively dampens the power angle oscillation and regulates the generator terminal voltage when a fault occurs. Simulation results are obtained by using the PAT （power analysis toolbox） for a SMIB （single machine infinite bus） system and a two area power system.

关键词： Synergetic control SVC based damping controllers particle swarm optimization.