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International Journal of minerals,metallurgy and materials 2015年第8期22卷 876-883页

作者： S.E.mousavi Ghahfarokhi S.Hosseini m.zargar shoushtari Department of physics Shahid Chamran University of Ahvaz

Sr Fe12-xNixO19 nanoparticles(x = 0–1) were synthesized by a combustion sol–gel method. Their structure, dielectric and magnetic properties were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEm), an LCR metry, and vibrating sample magnetometry(VSm).The results reveal that all samples of Ni doped compounds(Sr Fe12-xNixO19) with x magnetization and coercivity. In addition, Ni doping reduces the dielectric constant, dielectric loss, and alternating current(ac) electrical conductivity of the samples. The variation in ac conductivity(σac) with frequency shows that the electrical conductivity in these ferrites is mainly attributed to the electron hopping ***; all the single-phase Ni doped samples are suitable for use in magnetic recording media and microwave devices.

关键词： magnetic particles nanoparticles structure dielect

Validation of the Wiedemann–Franz law in a granular s-wave superconductor in the nanometer scale

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Chinese Physics B 2017年第3期26卷 506-514页

作者： A Yousefvand H Salehi m.zargar shoushtari Department of Physics Shahid Chamran University of Ahvaz Ahvaz Iran

The present study tries to evaluate the validity of the Wiedemann-Franz law in a granular s-wave superconductor in the presence of concentrated impurities. By using Green＇s function method and the Kubo formula technique, three distinct contributions of the Aslamazov-Larkin, the maid-Thompson and, the density of states are calculated for both the electrical conductivity and the thermal conductivity in a granular s-wave superconductor. It is demonstrated that these different con- tributions to the fluctuation conductivity depend differently on the tunneling because of their different natures. This study examines the transport in a granular superconductor system in three dimensions in the limit of large tunneling conductance, which makes it possible to ignore all localization effects and the Coulomb interaction. We find that the tunneling is efficient near the critical temperature and that there is a crossover to the characteristic behavior of a homogeneous system. When it is far from the critical temperature, the tunneling is not effective and the system behaves as an ensemble of real zero-dimensional grains. The results show that the Wiedemann-Franz law is violated in both temperature regions.

关键词： granular superconductor s-wave impurity vertex fluctuation propagator

Pretest analysis of shake table response of a two-span steel girder bridge incorporating accelerated bridge construction connections

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 169-184页

作者： Elmira shoushtari mSaiid SAIIDI Ahmad ITANI mohamed AmOUSTAFA Department of Civil and Environmental Engineering University of NevadaReno NV 89557USA

This paper presents pretest analysis of a shake table test model of a 0.35-scale,two-span,steel plate girder *** objective of pretest analysis was to obtain an insight on the seismic response of the bridge model during the shake table *** bridge included seat type abutments,full-depth precast deck panels,and a two-column bent in which columns were pinned to the footing and integral with *** accelerated bridge construction connections were incorporated in the bridge *** analytical model was developed in OpenSees and was subjected to ten input bi-directional earthquake motions including near-fault and far-field *** overall seismic response of the bridge was satisfactory for all the earthquake records at 100%,150%,and 200%design *** connections and capacity-protected components remained elastic,and the average ductility capacity surpassed the ductility demand even at 200%design *** experimental fragility curves developed for RC bridge columns,it was predicted that there was a probability of 45%that columns would undergo the imminent failure in the last run and a probability of 30%for their failure.

关键词： shake table test accelerated bridge construction steel girder bridge OpenSEES UHPC simple for dead continuous for live

Radical scavenging and antibacterial activity of Arnebia benthamii methanol extract

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Asian Pacific Journal of Tropical medicine 2012年第10期5卷 766-772页

作者： Showkat A Ganie Asima Jan Sabeera muzaffar Bilal A zargar Rabia Hamid m Afzal zargar Department of Biochemistry University of Kashmir Department of Food Science and Technology University of Kashmir Department of Pharmaceutical Sciences University of Kashmir

Objective:To evaluate in vitro antioxidant and antibacterial activity of methanolic extract of Arnebia benthamii（***） whole ***:Plasmid damage was analyzed by agarose gell *** thymus DNA was monitored by TBARS ***, reducing power and lipid peroxidation was evaluated by using standard *** assay was monitored by disc diffusion ***:DPPH radical scavenging and hydroxyl radical scavenging potential of the plant revealed that the extract to be active radical ***(Fe3+-Fe2+) power and lipid peroxidation inhibition efficiency（TBARS assay） of the extract was also evaluated and the extract showed promising activity in preventing lipid peroxidation and might prevent oxidative damages to *** extract offered a significant protection against plasmid and calf thymus UNA damage induced by hydroxyl radicals. The extract was also evaluated on different bacterial strains and the maximum antibacterial activity was exhibited against Escherichia coli（***） when compared with standard drug. Conclusions:These findings demonstrate that the methanol extract of *** has excellent anti-oxidant activities and could be considered as a potential source of lead molecules for pharmaceutical industries.

关键词： Free radicals Lipid peroxidation DPPH TBARS DNA damage Antibacterial activity Arnebia benthamii

Relative Canonical modules and Some Duality Results

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Algebra Colloquium 2019年第2期26卷 351-360页

作者： majid Rahro zargar Department of Engineering Sciences Faculty of Advanced Technologies University of Mohaghegh Ardabili Namin Ardabil Iran Department of Engineering Sciences Faculty of Advanced Technologies Sabalan University of Advanced technologies (SUAT) Namin Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM)

Let (R, m) be a relative Cohen–macaulay local ring with respect to an ideal a of R and set c to be ht a. We investigate some properties of the matlis dual of the R-module H^ca(R), and we show that such modules behave like canonical modules over Cohen–macaulay local rings. moreover, we provide some duality and equivalence results with respect to the module H^ca(R)^∨, and these results lead us to achieve generalizations of some known results, such as the local duality theorem, which have been provided over a Cohen–macaulay local ring admiting a canonical R-module.

关键词： local cohomology canonical module complex relative Cohen-macaulay module

THERmALLY STABLE POLYmERS CONTAINING 1,3,4-OXADIAZOLE UNITS OBTAINED FROm HUISGEN REACTION

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Chinese Journal of Polymer Science 2012年第1期30卷 36-44页

作者： Y.mansoori G.Barghian B.Koohi-zargar Gh.Imanzadeh m.Zamanloo Department of Applied Chemistry College of Science University of Mohaghegh ArdabiliArdabil 56199-11367Iran

Thermally stable polymers containing 1,3,4-oxadiazole units have been synthesized through Huisgen reaction of the aromatic/aliphatic bis-tetrazole compounds with the aromatic/aliphatic bis-acid chlorides in pyridine as *** obtained polymers are insoluble or slightly soluble even in polar aprotic solvents such as DmSO and *** high inherent viscosity values（0.61-1.33 dL/g,in 0.125%H_2SO_4 at 25℃） were observed for these *** analyses of the polymers using DSC and TGA techniques showed that the polymers have improved thermal *** glass transition temperature has not been observed in the fully aromatic polymers,but the polymers obtained from 5-[6-（1H-tetrazol -5-yl）hexyl]-lH-tetrazole（Ⅳ） showed very clear T_g.A model reaction was also investigated and the resulting bis-1,3,4-oxadiazole compound was characterized by conventional spectroscopy methods.

关键词： 1 3 4-Oxadiazole Thermally stable polymers Bis-tetrazole Huisgen reaction

POLYAmIDES WITH PENDANT 1,3,4-OXADIAZOLE AND PYRIDINE mOIETIES

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Chinese Journal of Polymer Science 2012年第1期30卷 112-121页

作者： Yagoub mansoori Behzad Koohi-zargar Hemayat Shekaari mohammad Reza Zamanloo Gholam Hassan Imanzadeh Department of Applied Chemistry College of Science University of Mohaghegh ArdabiliArdabil56199-11367Iran

A novel aromatic diamine,2-（5-（3,5-diaminophenyl）-l,3,4-oxadiazole-2-yl）pyridine（POBD）,containing a pyridine ring and a 1,3,4-oxadiazole moiety,was *** was used in a polycondensation with various aromatic and aliphatic diacid chlorides to generate a series of new aromatic polyamides with pendant 1,3,4-oxadiazole *** prepared polyamides were characterized by IR,elemental analysis and through the synthesis of model *** properties of the synthesized polyamides have been studied by DSC,TGA and inherent viscosity measurements. Relatively high inherent viscosity values（0.76-1.62 dL/g,in 0.125%H_2SO_4 at 25℃） were observed for these compounds. Number average molecular weight（m_n） of the polymers was measured by vapor phase osmometry（VPO）.The introduction of bulky side chains in the structure of aromatic polyamides led to increased solubility of these polymers in common polar and aprotic solvents,such as DmF,DmSO,NmP and DmAc,which allowed thin films to be cast from polymer solutions. The highest molecular weight（m_n = 51190） was observed for polymer（DC）,which was prepared from pyridine-2,6-dichlorocarbonyl.

关键词： Polyamide 1 3 4-Oxadiazole Inherent viscosity Vapor phase osmometry Polycondensation

maximum modulus of Polynomials

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Analysis in Theory and Applications 2017年第2期33卷 110-117页

作者： B.A.zargar Bashir Shaista Department of mathematics University of KashmirSrinagar190006Jammu&KashmirIndia

The result is best possible. In this paper we shall present a refinement of this result and some other related results.

关键词： maximum modulus growth of polynomial derivative.

Experimental investigation into L-Arg and L-Cys eco-friendly surfactants in enhanced oil recovery by considering IFT reduction and wettability alteration

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Petroleum Science 2020年第1期17卷 105-117页

作者： Hamed Foroughi Asl Ghasem.zargar Abbas Khaksar manshad mohammad Ali Takassi Jagar A.Ali Alireza Keshavarz Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AbadanIran Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AhwazIran Department of Petroleum Engineering Faculty of EngineeringSoran UniversitySoranKurdistan RegionIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilKurdistan RegionIraq School of Engineering Edith Cowan UniversityJoondalupWA 6027Australia

Surfactant flooding is an important technique used to improve oil recovery from mature oil reservoirs due to minimizing the interfacial tension(IFT)between oil and water and/or altering the rock wettability toward water-wet using various surfactant agents including cationic,anionic,non-ionic,and amphoteric *** this study,two amino-acid based surfactants,named lauroyl arginine(L-Arg)and lauroyl cysteine(L-Cys),were synthesized and used to reduce the IFT of oil–water systems and alter the wettability of carbonate rocks,thus improving oil recovery from oil-wet carbonate *** synthesized surfactants were characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses,and the critical micelle concentration(CmC)of surfactant solutions was determined using conductivity,pH,and turbidity *** results showed that the CmCs of L-Arg and L-Cys solutions were 2000 and 4500 ppm,*** was found that using L-Arg and L-Cys solutions at their CmCs,the IFT and contact angle were reduced from 34.5 to 18.0 and15.4 mN/m,and from 144°to 78°and 75°,***,the L-Arg and L-Cys solutions enabled approximately 11.9%and 8.9%additional recovery of OOIP(original oil in place).It was identified that both amino-acid surfactants can be used to improve oil recovery due to their desirable effects on the EOR mechanisms at their CmC ranges.

关键词： Chemical EOR Amino-acid surfactant IFT Wettability Coreflooding

The effect of administrating hyoscine bromide on pregnancy rate before embryo transfer in ART cycles

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Open Journal of Obstetrics and Gynecology 2013年第7期3卷 586-592页

作者： mahvash zargar Shiva Kajbaf masoud Hemadi Fertility Infertilty and Perinatology Research Center School of Medicine Ahvaz Jundishapur University of Medical Sciences Ah- vaz Iran

Assisted reproductive technology methods i.e., IVF and ICSI were extensively used for treatment of infertility. Although, these methods have many advantages but ART pregnancy rate remains low (30% - 35%). It seems that uterine peristalsis occurred after rhCG administration in turn resulting to impair implantation of the transferred embryos. Therefore this study was conducted to possess of whether hyoscine bromide can effectively alleviate uterine contraction and then have any effect on the reproductive outcome. Healthy women who underwent IVF or ICSI cycles (n = 142) were randomly assigned to one of two groups at the start of the cycle. Group control (n = 71) without applied hyoscine and group experiment (n = 71) applied hyoscine (25 mg). Controlled ovarian hyperstimulation was induced with follicle stimulating hormone (FSH). Sperm preparation and ovarian puncture for in vitro maturation and fertilization (IVF) of oocyte were carried out for 42 hours after rhCG injection. Two weeks after rhCG injection, bhCG pregnancy test to determine pregnancy outcome in both groups was done and the outcome results, along with other information were recorded separately. The pregnancy rate in experimental group was significantly higher than that of control group. when all of the cycles with or without giving 25 mg of hyosine were stratified by the mean total follicles (more/less than 2 follicles) and embryos (more/less than25 kg/m2), the Patients’ age, the quality grade of embryos and infertility duration (more/less than 5 years), the reproductive outcome, in overall, in the subjects with more than 10 oocytes, 5 embryos, more than quality A and B grades of embryos, less than 35 years age and also less than 5 years infertility duration was more pronounced than the other patients. But the other parameter was not affected by the reproductive outcome. Clinical or statistical improvement of the reproductive outcome could be demonstrated in the hyosine treated group especially with incre

关键词： Assisted Reproductive Technology (ART) Hyoscine Pregnancy Embryo Transfer