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Collisional Efect on Weibel Instability with Semi-Relativistic maxwellian Distribution Function

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Communications in Theoretical Physics 2014年第1期61卷 127-130页

作者： m.mahdavi H.Khanzadeh Physics Department Mazandaran University

In this paper, the Coulomb collisional effect of electron-ion on the growth rate of Weibel instability is investigated based on the semi-relativistic maxwellian distribution function in dense and unmagnetized plasma. An analytical expression was derived for the dispersion relation of Weibel instability for two limit cases [ξ = ω＇/k‖T‖ 〉〉 1 and ｜ξ｜〈〈 1. In limit ｜ξ｜〉〉 1 the dispersion relation only includes a real part and in limit ｜ξ｜〈〈 1 the imaginary part of the frequency of waves＇ instability plays a role in the dispersion relation. In limit ｜ξ｜〈〈 1, the two quantities μ and η, that are due to the relativistic and collisional effects, will appear in the growth rate of Weibel instability. The growth rate of Weible istability will be increased through decreasing the Coulomb collisional frequency and also increasing the temperature anisotropic parameter in strong relativistic limit.

关键词： Weibel instability Coulomb collisional growth rate semi-relativistic maxwellian distribution

Efective Parameters on Energy Losses of Fast Electron in Fusion mediums

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Communications in Theoretical Physics 2013年第10期60卷 491-495页

作者： m.mahdavi S.F.Ghazizadeh Physics Department Mazandaran University Physics Department Tehran Payam-e-Noor University

The stopping and scattering of fast electrons in a dense plasma relevant to inertial confinement fusion （ICF） are investigated numerically with the latest improved cross section equations. Binary and collective effects are considered to determine beam transport parameters such as range, penetration depth, spreading processes as straggling and blooming versus electron energy and plasma parameters. Blooming and straggling effects, which act as consequences of scattering with statistical assumption in collisions, lead to a non-uniform, extended region of energy deposition. Finally the mean angle of deflections is calculated for different plasma energies.

关键词： scattering stopping power ICF binary collisions collective effect straggling blooming

Ignition Conditions for Simulated Fuel Pellets in Degenerate Plasma

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Plasma Science and Technology 2013年第4期15卷 323-328页

作者： m. mahdavi A. GHOLAmI Physics Department Mazandaran University

A high-density, low-temperature plasma can be obtained during the compression phase in inertial confinement fusion. When high density and low temperature are reached in the plasma in the fast ignition approach, the plasma electrons can be degenerate. The electronic stopping of a slow ion is smaller than that given by the classical formula, because some transitions between the electron states are forbidden. In this case, bremsstrahlung emission is strongly sup- pressed and the ignition temperature becomes lower than that in classical plasma. The equations that predict the behavior of these plasmas are different from the classical ones, and this is the main factor in the process of decreasing the ignition temperature of the plasma. In this work, physical conditions of ignition are studied by calculating the effect of radiation loss on the ignition temperature for a simulated fuel pellet, （D/Tx/3Hey）, in degenerate plasma. In fast ignition, the energy needed for obtaining high densities is minimized and the gain can be increased considerably.

关键词： inertial fusion degenerate plasma ignition temperature bremsstrahlungemission

Influence of Aluminum Content on mechanical Properties and Cold Workability of Fe-33Ni-15Co Alloy

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Journal of Iron and Steel Research International 2012年第2期19卷 67-72页

作者： m Safavi S m Abbasi R mahdavi Department of materials Science and Engineering Semnan University Advanced materials Research Laboratory (AmRL) Department of Mechanical Engineering K.N. Toosi University of Technology Department of materials Science Azad University

The influence of 0.01% to 0. 25% of Aluminum content （in mass percent） on the mechanical properties and cold workability of low thermal expansion Fe-33Ni-15Co sheets in the annealed and hot rolled condition was investigated. Addition of Al up to 0.15 % resulted in the increase of ductility and tougianess and improvement of workability. Besides, achievement of fine grain structure and increase in the amount of annealing twins caused ductility to improve. Addition of Al higher than 0.15 % led to the increase in oxidation reaction during melting process and to refine under argon atmosphere. This caused the volume fraction of Al containing inclusions to increase and consequently the ductility and toughness to decrease.

关键词： Fe-33Ni-15Co alloy A1 content mechanical property cold workability

Application of digital techniques to identify aquifer artificial recharge sites in GIS environment

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International Journal of Digital Earth 2013年第6期6卷 589-609页

作者： A.mahdavi S.H.Tabatabaei R.mahdavi m.R.Nouri Emamzadei Department of Water Engineering Shahrekord UniversityShahrekordIran Department of Natural Resources Engineering Hormozgan UniversityBandar AbbasIran

Because the groundwater is considered as the major source of 99%of all retrievable fresh water,optimization of its usage would be very ***water artificial recharge(GAR)using surface water is the recommended solution because that increases the aquifer *** of aquifer storage site is the first step in designing GAR *** main objective of this research is the identification of suitable GAR sites scattered in the Shahrekord plain,Chaharmahal-va-Bakhtiari province of Iran,using Boolean and Fuzzy *** affecting GAR including ground surface slope,soil infiltration rate,vadoze zone thickness,electrical conductivity of the surface water,land-use,and stream network were *** provision of digital maps,they were classified,weighted,and integrated through Boolean and Fuzzy *** result revealed almost 4.25%of the whole plain area is appropriate for GAR based on ***,4.79 and 17.94%of the plain area are suitable and rather favorable,respectively,based on ***,34 locations were introduced with priorities A,B,and AB as being potentially suitable for *** relationship between geomorphology and suitable areas for GAR based on Boolean and Fuzzy method indicated that the majority of these areas were located on colluvial fans units.

关键词： groundwater artificial recharge Fuzzy and Boolean logic geomorphology Shahrekord plain

Existence of Nonabelian Free Subgroups in the maximal Subgroups of GLn（D）

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Algebra Colloquium 2014年第3期21卷 483-496页

作者： H.R. Dorbidi R. Fallah-moghaddam m. mahdavi-Hezavehi Department of mathematical Sciences Sharif University of 3bchnology P.O. Box 11155-3415 Tehran Iran

Given a non-commutative finite dimensional F-central division algebra D, we study conditions under which every non-abelian maximal subgroup m of CLn （D） contains a non-cyclic free subgroup. In general, it is shown that either m contains a non-cyclic free subgroup or there exists a unique maximal subfield K of mn（D） such that NCLn（D）（K＊） = m, K＊ △ m, K/F is Galois with Gal（K/F） ≌ m/K＊, and F[m] = in（D）. In particular, when F is global or local, it is proved that if （[D ： F], Char（F）） = 1, then every non- abelian maximal subgroup of GL1 （D） contains a non-cyclic free subgroup. Furthermore, it is also shown that GLn（F） contains no solvable maximal subgroups provided that F is local or global and n ≥ 5.

关键词： free subgroup maximal subgroup central simple algebralotion

Porous solid inspired hyper-crosslinked polymer liquids with highly efficient regeneration for gas purification

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Science China materials 2022年第7期65卷 1937-1942页

作者： Stefan J.D.Smith Colin D.Wood Paul H.m.Feron Hamidreza mahdavi Roger J.mulder Cara m.Doherty matthew R.Hill Xavier mulet CSIRO manufacturing Private Bag 10Clayton SouthVIC 3169Australia Department of Chemical Engineering Monash UniversityClaytonVIC 3800Australia Australian Resources Research Centre KensingtonWA 6155Australia CSIRO Energy P.O.Box 330NewcastleNSW 2300Australia

Separation media that combine the desired material properties within a single material for a given process remain an ongoing challenge for the gas separations in *** integration of porous solid adsorbents is difficult due to their limited volumetric capacity,whereas issues of volatility and high regeneration temperatures exist for liquid amines and physical ***,we report a family of polymer liquids inspired by hyper-crosslinked polymers(HCPs),a class of highly swellable network *** with a chemically similar porous solid,the HCP-liquids demonstrate good volumetric capacity and improved selectivity of carbon dioxide over *** appears to be enhanced by intramolecular swelling of the HCP-liquids at elevated pressures,while guests are strongly rejected from the HCP-liquids at slightly elevated temperatures,leading to highly efficient *** of adsorption and specific heat capacity of the HCP-liquids are also low,further suggesting favourable process *** being easily prepared at scale,the presented HCP-liquids represent a promising step towards a material with the requisite properties to replace conventional scrubbing solvents to drastically reduce the footprint and energy needs of gas separations.

关键词： hyper-crosslinked polymers swellable network efficient regeneration porous liquids gas sorption

Biomass and carbon stocks in three types of Persian oak(Quercus brantii ***)of Zagros forests in a semi-arid area,Iran

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Journal of Arid Land 2020年第5期12卷 766-774页

作者： Ali mahdavi Soghra SAIDI Yaghob IRANmANESH mostafa NADERI Faculty of Agriculture and Natural Resources Ilam UniversityIlam 69315516Iran Research Division of Natural Resources Chaharmahal and Bakhtiari Agricultural and Natural Resources Research and Education CenterAREEOShahrekord ***Iran

Persian oak(Quercus brantii ***)is a dominant tree species of Zagros forests in a semi-arid area,western ***,the capacity of biomass and carbon stocks of these forests is not well *** selected three types of oak,i.e.,seed-originated oak,coppice oak and mixed(seed-originated and coppice)oak of Zagros forests in Dalab valley,Ilam Province,Iran to survey the capacity of biomass and carbon stocks in *** plots with an area of 1000 m2 were systematically and randomly assigned to each type of *** characteristics of trees,such as diameter at breast height(DBH),height,crown diameter and the number of sprouts in each plot were ***,aboveground biomass(AGB),belowground biomass(BGB),aboveground carbon stock(AGCS)and belowground carbon stock(BGCS)of each tree in plots were calculated using allometric *** litterfall biomass(LFB)and litterfall carbon stock(LFCS)were measured in a quadrat with 1 m×1 m in each ***-way analysis of variance and Duncan's test were performed to detect the differences in biomass and carbon stocks among three types of *** showed that AGB,BGB and BGCS were significantly different among three types of *** highest values of AGB,AGCS,BGB and BGCS in seed-originated oak were 76,043.25,14,725.55,36,737.79 and 7362.77 kg/hm2,***,the highest values of LFB and LFCS in seed-originated oak were 3298.33 and 1520.48 kg/hm2,respectively,which were significantly higher than those of the other two types of *** results imply the significant role of seed-originated oak for the regeneration of Zagros *** conservation strategy of seed-originated oak is an important step in the sustainable management of Zagros forests in Iran.

关键词： biomass carbon stock seed-originated forest coppice forest Zagros forest

Underlying solvent-based factors that influence permanent porosity in porous liquids

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Nano Research 2022年第4期15卷 3533-3538页

作者： Hamidreza mahdavi Huacheng Zhang Lauren K.macreadie Cara m.Doherty Durga Acharya Stefan J.DSmith Xavier mulet matthew R.Hill Department of Chemical Engineering Monash UniversityClaytonVIC 3800Australia CSIRO manufacturing Private Bag 10Clayton SouthVIC 3169Australia School of Chemistry University of SydneySydney 2006Australia

Porous liquids(PLs)offer the potential to combine the ready handling and mature industry status of liquid absorbents,with the high permanent porosity of metal organic *** be functional,these nanocomposites need to satisfy a number of performance parameters,such as stability and viscosity of the porogen-solvent combination,avoiding solvent penetration into metal organic framework(mOF)pores,suitable capacities,and kinetics for gas *** this work,we systematically investigate the component materials to elucidate the parametric space where stable photoluminescence(PL)can be *** this situation,deeper conclusions were able to be drawn with regard to the influence of hydrophobicity/philicity on the properties of the resulting *** imidazolate frameworks(ZIFs)were combined with a range of solvents varying in steric bulk,to deliver CO_(2)sorption capacities as high as 4.2 mmol·g^(-1)at 10 *** findings may have broader implications for future investigations of this tantalising field of nanocomposites.

关键词： zeolitic imidazolate frameworks porous liquids permanent porosity gas sorption