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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 487-507页

作者： mohammad hadikhan tehrani Faramarz Khoshnoudian Department of Civil and Environmental Engineering Amirkabir University of Technology (Tehran Polytechnic)

Performance based design becomes an effective method for estimating seismic demands of buildings. In asymmetric plan tall building the effects of higher modes and torsion are crucial. The consecutive modal pushover （CMP） procedure is one of the procedures that consider these effects. Also in previous studies the influence of soil-structure interaction （SSI） in pushover analysis is ignored. In this paper the CMP procedure is modified for one-way asymmetric plan mid and high-rise buildings considering $SI. The extended CMP （ECMP） procedure is proposed in order to overcome some limitations of the CMP procedure. In this regard, 10, 15 and 20 story buildings with asymmetric plan are studied considering SSI assuming three different soil conditions. Using nonlinear response history analysis under a set of bidirectional ground motion; the exact responses of these buildings are calculated. Then the ECMP procedure is evaluated by comparing the results of this procedure with nonlinear time history results as an exact solution as well as the modal pushover analysis procedure and FEMA 356 load patterns. The results demonstrate the accuracy of the ECMP procedure.

关键词： consecutive modal pushover procedure soil-structure interaction bidirectional ground motion tall buildings seismic demands engineering demand parameters

Normal Crossings Singularities for Symplectic Topology:Structures

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Acta Mathematica Sinica,English Series 2024年第1期40卷 107-160页

作者： mohammad FARAJZADEH-tehrani Mark MCLEAN Aleksey ZINGER The University of Iowa MacLean HallIowa CityIA 52241 Department of Mathematics Stony Brook UniversityStony BrookNY 11794

Our previous papers introduce topological notions of normal crossings symplectic divisor and variety,show that they are equivalent,in a suitable sense,to the corresponding geometric notions,and establish a topological smoothability criterion for normal crossings symplectic *** present paper constructs a blowup,a complex line bundle,and a logarithmic tangent bundle naturally associated with a normal crossings symplectic divisor and determines the Chern class of the last *** structures have applications in constructions and analysis of various moduli *** a corollary of the Chern class formula for the logarithmic tangent bundle,we refine Aluffi’s formula for the Chern class of the tangent bundle of the blowup at a complete intersection to account for the torsion and extend it to the blowup at the deepest stratum of an arbitrary normal crossings divisor.

关键词： Normal crossings divisor Chern class Logarithmic tangent bundle

Determination of Copper by Flame Atomic Absorption Spectrometry after Preconcentration with Activated Carbon Impregnated with a New Schiff Base

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Chinese Journal of Chemistry 2005年第10期23卷 1437-1442页

作者： SABER tehrani, mohammad RASTEGAR, Faramarz PARCHEHBAF, Ayob REZVANI, Zolfaghar Department of Chemistry Faculty of Science Science and Research Campus lslamic Azad University Tehran Iran Plate-Form Analitique lnorganique Lois Pasteur University Strasburg France Department of Chemistry Faculty of Science Azarbaijan Tarbiat Moallem University Tabriz Iran

A simple and reliable method for the extraction and determination of trace amounts of copper（Ⅱ） ions using activated carbon （AC） impregnated by a new Schiff base 5-[（4-heptyloxyphenyl）azo]-N-（4-propyloxyphenyl）-salicylaldimine （HPPS） and atomic absorption spectrometry is presented. Recovery efficiency and the influence of pH value, volume of sample solution, effect of different eluents, and interfering ions were evaluated. The limit of detection （3σ） was 2.62 ***^-1 and the relative standard deviation （n=10） was 1.5%. Under optimum conditions, the copper ions were concentrated 25 fold using 250 mL of sample solution and 10 mL of eluent. This procedure has been successfully applied to the determination of copper in different water samples.

关键词： preconcentration determination copper flame atomic absorption spectrometry activated carbon

Prevalence and risk factors of avian influenza H9N2 among backyard birds in Iran in 2015

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Asian Pacific Journal of Tropical Medicine 2019年第12期12卷 559-564页

作者： mohammad Hossein Fallah Mehrabadi Arash Ghalyanchilangeroudi mohammad Hasan Rabiee Farshad tehrani Razi Vaccine and Serum Research Institute Agricultural ResearchEducation and Extension Organization(AREEO)TehranIran Department of Microbiology and Immunology Faculty of Veterinary MedicineUniversity of TehranTehranIran Division of Epidemiology&Zoonosis Department of Food Hygiene&Quality ControlFaculty of Veterinary MedicineUniversity of TehranTehranIran Department of Health and Management of Poultry Diseases Iranian Veterinary OrganizationTehranIran

Objective: To investigate the prevalence and the risk factors of H9 N2 avian influenza among backyard birds in Iran between October and November 2015. Methods: In this study, a total of 15 500 blood samples and 2 884 cloacal swab samples of backyard birds were collected in villages of Iran between October and November 2015. Then, serum samples were examined with the hemagluttination inhibition test and cloacal swab samples were pooled together and examined by RT-PCR. The samples that had serological titer ≥ 4(log2) and villages that had at least one seropositive sample were considered ***: Out of 559 villages, 526(94.10%) were seropositive for the infection. Among 15 500 serum samples, 7 468(48.18%) samples were seropositive for the infection. The seroprevalence according to species was 54.02% among chickens, 17.59 % among ducks, 18.73% among turkeys, 84.21% among pigeons and 12.15% among ostriches, partridges and pheasants. Based on molecular test, 3.04% villages were positive. The seroprevalence in hot and humid area was less than that in cold and humid area(P<0.05).Conclusions: H9 N2 avian influenza has high seroprevalence among backyard birds of Iran. Therefore, preventive measures such as biosecurity Practices and monitoring should be applied to reduce the prevalence.

关键词： Influenza H9N2 Iran Backyard birds

Determination of Pb（Ⅱ） and Cu（Ⅱ） by Electrothermal Atomic Absorption Spectrometry after Preconcentration by a Schiff Base Adsorbed on Surfactant Coated Alumina

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Chinese Journal of Chemistry 2006年第6期24卷 765-769页

作者： SABER tehrani, mohammad RASTEGAR, Faramarz PARCHEHBAF, Ayob KHATAMIAN, Masoomeh Department of Chemistry Science and Research Campus Islamic Azad University Tehran Iran Plate-Form Inorganic Analytical Chemistry Louis Pasteur University Strasbourg France Department of Inorganic Chemistry Faculty of Chemistry University of Tabriz Tabriz Iran

1,2-Bis（salicylidenamino）ethane loaded onto sodium dodecyl sulfate-coated alumina was used as a new chelating sorbent for the preconcentration of traces of Pb（Ⅱ） and Cu（Ⅱ） prior to atomic absorption spectrometric determination. The influence of pH, flow rates of sample and eluent solutions, and foreign ions on the recovery of Pb（Ⅱ） and Cu（Ⅱ） by this sorbent has been studied. The retained ions were eluted with 4 mol·L nitric acid and determined by electrothermal atomic absorption spectrometry （ETAAS）. The data of limit of detection （3σ） for Pb（Ⅱ） and Cu（Ⅱ） were found to be 8.57 and 2.69 ng·L^-1 respectively, while the enrichment factor for both ions was 100. The proposed method was successfully applied to determination of lead and copper in different water samples.

关键词： determination of lead and copper preconcentration 1,2-bis(salicylidenamino)ethane ETAAS

Preconcentration and Determination of Chromium Species Using Octadecyl Silica Membrane Disks and Flame Atomic Absorption Spectrometry

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Chinese Journal of Chemistry 2007年第12期25卷 1859-1865页

作者： MOGHIMI, Ali SABER-tehrani, mohammad WAQIF-HUSAIN, Syed mohammadHOSSEINI, Majid Department of Chemistry Islamic Azad University Varamin Campus Varamin Iran Department of Chem stry Faculty of Scence Scence and Research Campus lslamic Azad Universty Tehran Iran Department of Chemistry Islamic Azad University of Shahrood Shahrood Iran

A novel and selective method for the fast determination of trace amounts of chromium species in water samples has been developed. The procedure is based on the selective formation of chromium diethyldithiocarbamate complexes at different pH in the presence of Mn（Ⅱ） as an enhancement agent of chromium signals followed by elution with organic eluents and determination by atomic flame absorption spectrometry. The maximum capacity of the employed disks was found to be （396±3） pg and （376±2） pg for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The detection limit of the proposed method is 49 and 43 ng·L^-1 for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The proposed method was successfully applied for determination of chromium species Cr（Ⅲ） and Cr（Ⅵ） in different water samples.

关键词： solid phase extraction sodium diethyldithiocarbamate flame atomic absorption spectrometry octadecyl silica membrane disk

Deactivation studies of bifunctional Fe-HZSM5 catalyst in Fischer-Tropsch process

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Journal of Natural Gas Chemistry 2008年第3期17卷 242-248页

作者： Ali Nakhaei Pour Seyed Mehdi Kamali Shahri Yahya Zamani mohammad Irani Shohreh tehrani Research Institute of Petroleum Industry National Iranian Oil Company

A physical mixture of alkali-promoted iron catalyst with binder based on Fischer-Tropsch synthesis and an acidic co-catalyst （HZSM5） for syngas conversion to hydrocarbons was studied in a fixed bed micro reactor. Deactivation data were obtained during the synthesis over a 1400 h period. The deactivation studies on iron catalyst showed that this trend followed the phase transformation Fe2.2C （ ε′） → Fe5C2 （χ） → Fe3C （θ）, and the final predominant phase of the catalyst was Fe3C （θ）. Deactivation of zeolite component in bifunctional catalyst may be caused by coking over the zeolitic component, dealumination of zeolite crystals, and migration of alkali promoters from iron catalyst under synthesis conditions. The deactivation rate of iron catalyst was also obtained.

关键词： catalyst deactivation Fischer-Tropsch synthesis iron catalyst HZSM5 zeolite

Wavelet-based power management for hybrid energy storage system

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 779-790页

作者： Masoud MASIH-tehrani mohammad Reza HA’IRI YAZDI Vahid ESFAHANIAN Masoud DAHMARDEH Hassan NEHZATI Vehicle Dynamical Systems Research Laboratory School of Automotive EngineeringIran University of Science and TechnologyTehranIran School of Mechanical Engineering College of EngineeringUniversity of TehranTehranIran School of Automotive Engineering Iran University of Science and TechnologyTehranIran Vehicle Fuel and Environment Research Institute University of TehranTehranIran

A wavelet-based power management system is proposed in this paper with a combination of the battery and ultracapacitor(UC)hybrid energy storage system(HESS).The wavelet filter serves as a frequency-based filter for distributing the power between the battery and *** order to determine the optimal level of wavelet decomposition as well as the optimal activation power of the wavelet controller,an optimization procedure is *** proposed frequency-based power management system moderates the usage of battery current,consequently improving its *** with the conventional threshold-based power management systems,the proposed system has the advantage of enhanced battery and UC power management.A LiFePO4 battery is considered and its life loss is *** a case study,an electric motorcycle is evaluated in the federal test procedure(FTP)driving *** with a conventional energy storage system(ESS)and a state of available power(SoP)management systems,the results show an improvement for the battery lifetime by 115%and 3%,*** number of battery replacements is increased,and the energy recovery is *** 10-year overall costs of the proposed HESS strategy using wavelet are1500 dollars lower,compared with the ESS.

关键词： Wavelet filter Hybrid energy storage system(HESS) Power management system Ultracapacitor(UC) Lithium life loss model Battery Energy storage cost

The research and development on the antioxidants in prevention of diabetic complications

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Asian Pacific Journal of Tropical Medicine 2016年第9期9卷 801-808页

作者： mohammad Rahimi-Madiseh Afsaneh Malekpour-tehrani Mahmoud Bahmani Mahmud Rafieian-kopaei Medical Plants Research Center Shahrekord University of Medical Sciences Department of Social Medicine Shahrekord University of Medical Sciences Faculty of Medicine and Clinical Microbiology Research Center

Diabetes mellitus can damage the eyes,kidneys,nerves and *** and macrovascular disorders are the leading causes of morbidity and mortality in diabetic *** can increase the indicators of lipid peroxidation and oxidative stress in which free radicals have the main role in the pathogenesis of these ***,antioxidants which combat oxidative stress should be able to prevent and repair free radicals induced *** free radicals contribute to kidney damage,atherosclerosis,diabetes,heart disease,nephrotoxicity and hepatotoxicity; however,clinical trials do not uniquely confirm a substantial impact on diabetic *** seems that antioxidants in vegetables,fruits and grains help preventing diabetes complications; however,there is little evidence that taking single antioxidants such as vitamin E or vitamin C protect these *** findings about combination antioxidants are also complicated and not entirely *** this review paper we tried to present the role of oxidative stress on microvascular complications of type2 diabetes *** objective of this paper is to review the new findings about the role of various antioxidants on prevention and treatment of diabetes mellitus as well as its complications including retinopathy,nephropathy and neuropathy.

关键词： Diabetic Nephropathy Natural antioxidants Diabetes complications Nephropathy Neuropathy Retinopathy

Synthesis and antibacterial activity of Schiff bases of 5-substituted isatins

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Chinese Chemical Letters 2016年第2期27卷 221-225页

作者： Kamaleddin Haj mohammad Ebrahim tehrani Maryam Hashemi Maryam Hassan Farzad Kobarfard Shohreh Mohebbi Department of Medicinal Chemistry School of PharmacyZanjan University of Medical SciencesZanjanlran Department of Pharmaceutical Biotechnology School of PharmacyZanjan University of Medical SciencesZanjanIran Department of Medicinal Chemistry School of PharmacyShahid Beheshti University of Medical SciencesTehranIran Phytochemistry Research Center Shahid Beheshti University of Medical SciencesTehranIran

Based on the existing reports on the bioactive isatin derivatives, a number of Schiff bases were synthesized by reacting 5-substituted isatins with bioactive amines/hydrazides and their structures were confirmed using spectroscopic methods such as NMR, IR and mass spectrometry. Furthermore, Nbenzylation of isatin followed by the Schiff base formation furnished a new series of compounds（11a-13c） which allowed the analysis of the effect of isatin N-substitution on the bioactivity of the resulting compounds. The antibacterial activity of the synthesized derivatives was evaluated using a microtiter plate method on a series of gram positive and gram negative bacterial strains. Compounds 2d, 3b, 5c and 6a were among the most potent derivatives against Pseudomonas aeruginosa（MIC = 6.25 μg/m L）.Analysis of the structure-activity relationship showed that the incorporation of（thio）urea-based Schiff bases lead to more potent derivatives with a broader spectrum of antibacterial activity. In addition,highly lipophilic compounds such as 11a-12c did not show any measurable antibacterial activity, which implies that an optimal lipophilicity might be an important requirement for the antibacterial activity of the studied isatins. Finally, the finding that hydantoin derivatives of N-benzylisatins（13a-13c） still exhibit some antibacterial activity prompted us to consider exploring the bioactivity of more diverse derivatives of isatin-aminohydantoin Schiff bases（compounds 1a-1d） in our future studies.

关键词： Synthesis Isatin Schiff base Hydantoin Antibacterial