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Nuclear Science and Techniques 2018年第10期29卷 221-228页

作者： M.R.pahlavani p.mehdipour Department of physics Faculty of Basic Science University of Mazandaran

photofission fragments mass yield for^(232)Th,^(234;238) U,^(237) Np, and^(239;240;242) pu isotopes are *** calculations are done using a developed approach based on Gorodisskiy's phenomenological formalism. The Gorodisskiy's method is developed to be applied for the neutron-induced fission. Here we revised it for application to photofission. The effect of emitted neutron prior to fission on the fission fragment mass yields has also been studied. The peak-to-valley ratio is extracted for the240 pu isotope as a function of energy. Obtained results of the present formalism are compared with the available experimental data. Satisfactory agreement is achieved between the results of present approach and the experimental data.

关键词： Fission fragments Fragment mass yield photofission Neutron fission Heavy nuclei peak-to-valley

Kinetic energy distribution for neutron-induced fission of neptunium isotopes

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Chinese physics C 2021年第2期45卷 502-508页

作者： p.mehdipour Kaldiani Department of physics Naragh BranchIslamic Azad UniversityNaraghIran

The mean total kinetic energy as a function of fission fragments,thedistribution,is presented for neutron-induced fission of ^(235-239)Np using the scission point *** calculated results offor neutron-induced fission of ^(237,238) Np are compared with the available experimental data to obtain the deformation parameters in the scission point *** deformation parameters of fission fragments are discussed at the scission *** calculated results are also compared with the results from other methods and with experimental *** behavior of thedistribution is then studied for the neutron-induced fission of *** indicates that thevalues for neutron-induced fission of actinides with odd mass numbers are greater than for those with even mass numbers.

关键词： scission point model total kinetic energy neutron-induced fission fission fragments deformation parameters

Deformation parameter changes in fission mass yields within the systematic statistical scission-point model

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Communications in Theoretical physics 2021年第7期73卷 95-105页

作者： payam mehdipour Kaldiani Department of physics Naragh BranchIslamic Azad UniversityNaraghIran

The fission fragment mass-yields are evaluated for pre-actinide and actinide isotopes using a systematic statistical scission point *** total potential energy of the fissioning systems at the scission point is presented in approximate relations as functions of mass numbers,deformation parameters and the temperature of complementary fission *** collective temperature,Tcoll,and the temperature of fission fragments,Ti,are separated and the effect of collective temperature on mass yields results is *** fragment temperature has been calculated with the generalized superfluid *** sum of deformation parameters of complementary fission fragments has been obtained by fitting the calculated results with the experimental *** investigate the transitions between symmetric and asymmetric modes mass yields for pre-actinide and heavy actinides are calculated with this *** transition from asymmetric to symmetric fission is well reproduced using this systematic statistical scission point *** calculated results are in good agreement with the experimental data with Tcoll=2 Me V at intermediate excitation energy and with T_(coll)=1MeV for spontaneous *** the Langevin model,in the scission point model,a constraint on the deformation parameters of fission fragments has little effect on the results of the mass yield.

关键词： mass yields deformation parameters statistical scission point model symmetric and asymmetric modes fission fragments

Influence of glycine additive on corrosion and wear performance of electroplated trivalent chromium coating

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 544-554页

作者： Navid mehdipour Milad Rezaei Zeynab Mahidashti Department of Materials and Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)Hafez Ave.P.O.Box 15875-4413TehranIran

The aim of this study is to evaluate the effect of various molar ratios of glycine to chromium salt(Gly:Cr)and different current densities on the corrosion and wear behaviors of Cr(III)electroplated *** morphology and thickness of the coatings were investigated by scanning electron *** wear properties of the coatings were studied using pin on disk and hardness tests,while corrosion behavior of the coatings was identified using linear polarization,small amplitude cyclic voltammetry,and electrochemical impedance spectroscopy *** increasing the glycine concentration,a structure with low crack density was *** all molar ratios,maximum thickness and current efficiency was observed at a current density of 150 mA·cm?*** the electrochemical methods had a consistent result,and maximum corrosion resistance of approximately 16000Ω·cm2 was obtained in the case of Gly:Cr=3:1 and current density of 200 mA·cm?2.

关键词： electrodeposition trivalent chromium glycine corrosion resistance

HEAT-RESISTANT,pYRIDINE-BASED pOLYAMIDES CONTAINING ETHER AND ESTER UNITS WITH IMpROVED SOLUBILITY

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Chinese Journal of polymer Science 2010年第1期28卷 29-37页

作者： Hassan Ebadi Shahram mehdipour-Ataei Islamic Azad University of Shahreza P.O.Box 81145-311 ShahrezaIsfahanIran Iran polymer and petrochemical Institute P.O.Box 14965/115 TehranIran

A diamine containing ether and ester units, as basic monomer for the preparation of polyamides, was prepared via three consecutive reactions. Nucleophilic substitution reaction of 1,4-dihydroxy benzene with 4-nitrobenzoyl chloride produced 4-hydroxyphenyl 4-nitrobenzoate （HpNB）. Reduction of nitro groups to amino groups using Fe and HC1 resulted in preparation of 4-hydroxyphenyl 4-aminobenzoate （HpAB）. The diamine was synthesized through nucleophilic substitution reaction of HpAB with 2,6-dichloropyridine. The precursors and diamine were fully characterized by common methods, and the diamine was polycondensed with different diacid chlorides in the presence of an acid scavenger to prepare new polyamides. The polyamides were characterized, and their physical properties including thermal stability and behavior, inherent viscosity and solubility were studied.

关键词： polyamide polycondensation Diamine Ester Ether.

HEAT-RESISTANT pYRIDINE-BASED pOLY(ETHER-ESTER)S: SYNTHESIS, CHARACTERIZATION AND pROpERTIES

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Chinese Journal of polymer Science 2013年第1期31卷 171-178页

作者： Shahram mehdipour-Ataei Ali Mahmoodi Department of Chemistry Islamic Azad University

A pyridine-based diacid was synthesized via nucleophilic substitution reaction of 4-hydroxy benzoic acid with 2,6- dichloropyridine in the presence of potassium carbonate. The diacid was characterized using FT-IR and 1H-NMR spectroscopic methods and also with elemental analysis. polycondensation reaction of the diacid with different diols including 1,4-dihydroxy benzene, 1,5-dihydroxy naphthalene, bis-phenol A and bis-phenol-p resulted in preparation of pyridine-based poly（ether-ester）s. The polymers were characterized and their physical and thermal properties including inherent viscosity, molecular weight, solubility, thermal stability, thermal behavior and crystallinity were studied. They revealed high heat-resistance and improved solubility in polar solvents. Structure-property relations for the prepared polyester were also studied.

关键词： polyester polymer synthesis and characterization Thermal properties Structure-property relations.

SOLUBLE pOLYIMIDES FROM A SEMI-ALIpHATIC DIAMINE CONTAINING ESTER,AMIDE AND ETHER GROUpS

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Chinese Journal of polymer Science 2011年第1期29卷 93-100页

作者： Shahram mehdipour-Ataei Leila Akbarian-Feizi Iran polymer and petrochemical Institute P.O.Box 14965/115TehranIran

A diamine was synthesized by two successive reactions. Nucleophilic reaction of 4-hydroxybenzoic acid with terephthaloyl chloride yielded terephthaloyl bis（4-oxybenzoic） acid. Then reaction of this compound with 1,8-diamino-3,6- dioxaoctane via Yamazaki method resulted in preparation of diamine named terephthalic acid bis（4-{2-[2-（2-amino ethoxy）ethoxy]ethyl carbamoyl}phenyl） ester. After fully characterization it was used to prepare new polyimides through polycondensation with different dianhydrides using trimethylchlorosilane. Characterization of polymers was achieved by common methods and their physical properties including inherent viscosity, thermal behavior, thermal stability, crystallinity and solubility were studied. prepared polyimides showed improved solubility and good thermal stability.

关键词： polyimide polycondensation Synthesis Thermal properties

Noncommutative Singular Black Holes

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Communications in Theoretical physics 2010年第11期54卷 845-848页

作者： S.Hamid mehdipour Islamic Azad University Lahijan Branch

In this paper, applying the method of coordinate coherent states to describe a noncommutative model of Vaidya black holes leads to an exact （t - r） dependence of solution in terms of the noncommutative parameter σ.... 详细信息

关键词： Vaidya black hole noncommutative gravity black hole remnant

ATM in breast and brain tumors:a comprehensive review

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Cancer Biology & Medicine 2018年第3期15卷 210-227页

作者： Mehrdad Asghari Estiar parvin mehdipour Department of Medical Genetics School of Medicine Tehran University of Medical Sciences

The ATM gene is mutated in the syndrome,ataxia-telangiectasia(AT),which is characterized by predisposition to *** with AT have an elevated risk of breast and brain tumors Carrying mutations in ATM,patients with AT have an elevated risk of breast and brain *** increased frequency of ATM mutations has also been reported in patients with breast and brain tumors;however,the magnitude of this risk remains *** the exception of a few common mutations,the spectrum of ATM alterations is heterogeneous in diverse populations,and appears to be remarkably dependent on the ethnicity of *** review aims to provide an easily accessible summary of common variants in different populations which could be useful in ATM screening *** addition,we have summarized previous research on ATM,including its molecular *** attempt to demonstrate the significance of ATM in exploration of breast and brain tumors and its potential as a therapeutic target.

关键词： Breast cancer brain tumor DNA damage DNA repair

Noncommutative Inspired Reissner-Nordstrm Black Holes in Large Extra Dimensions

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Communications in Theoretical physics 2010年第3期53卷 503-513页

作者： Kourosh Nozari S.Hamid mehdipour Department of physics Faculty of Basic SciencesUniversity of Mazandaran Babolsar IRAN Research Institute for Astronomy and Astrophysics of Maragha Islamic Azad University Lahijan Branch

Recently, a new noncommutative geometry inspired solution of the coupled Einstein Maxwell field equations including black holes in 4-dimension is found. In this paper, we generalize some aspects of this model to the Reissner Nordstrom （RN） like geometries with large extra dimensions. We discuss Hawking radiation process based on noncommutative inspired solutions. In this framework, existence of black hole remnant and possibility of its detection in LHC are investigated.

关键词： quantum gravity black hole thermodynamics noncommutative spacetime large extra dimensions