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Investigation on leaching of m.lachite by citric acid

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International Journal of m.nerals,m.tallurgy and m.terials 2012年第9期19卷 782-786页

作者： m.A. shabani m. Irannajad A.R. Azadm.hr Departm.nt of m.ning & m.tallurgical Engineering Amirkabir University of Technology P.O. Box 15875-4413 Tehran *** Iran

Leaching of an oxidized copper ore containing m.lachite, as a new approach, was investigated by an organic reagent, citric acid. Sulfuric acid is the m.st com.on reagent in the leaching of oxide copper ores, but it has several side effects such as severe adverse im.act on the environm.nt. In this investigation, the effects of particle size, acid concentration, leaching tim., solid/liquid ratio, tem.erature, and stirring speed were optim.zed. According to the experim.ntal results, m.lachite leaching by citric acid was technically feasible. Optim.m.leaching conditions were found as follows： the range of particle size, 105-150 μm. acid concentration, 0.2 m. leaching tim., 30 m.n; solid/liquid ratio, 1：20 g/m.; tem.erature, 40℃; and stirring speed, 200 r/m.n. Under the optim.m.conditions, 91.61% of copper was extracted.

关键词： m.lachite copper ore treatm.nt leaching organic acids citric acid

Effect of Ablation Casting on m.crostructure and Casting Properties of A356 Alum.nium.Casting Alloy

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Acta m.tallurgica Sinica(English Letters) 2013年第1期26卷 85-91页

作者： V. Bohlooli m. shabani m.halli S. m. A. Boutorabi Casting Research Center School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST)

Recently the Ablation Casting Technology was invented as a new casting process to im.rove foundry products quality. In this study, the effects of processing variables on the porosity content, rnicrostructure and feedability of A356 casting alloy were investigated. Secondary dendrite arm.spacing （SDAS） and eutectic silicon m.r-phologies were studied to evaluate the influence of Ablation Casting on the rnicrostructure. Casting density was m.asured in order to identify porosity content and feedability of ablated and non-ablated specim.ns. In addition, solidification behavior of the sam.les was investigated by using therm.l analysis technique. The cooling curves and the first derivative curves were plotted and com.ared with each other. Results showed the ablation process could increase solidification rate significantly. In addition, the m.crostructural evidences revealed that Ablation Casting process results in m.re fine and hom.geneous structure com.ared to the non-ablated casting. The feedability im.roved, SDAS reduced to 35% and porosity content decreased to 3.84 vol.% by im.lem.nting this process. It concluded the Ablation Casting is an effective process to gain higher quality in alum.num.foundry.

关键词： Ablation Casting A356 alum.nium.alloy m.crostructure Porosity Cooling curve

Bioleaching of copper oxide ore by P seudom.nas aeruginosa

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International Journal of m.nerals,m.tallurgy and m.terials 2013年第12期20卷 1130-1133页

作者： m.A.shabani m.Irannajad A.R.Azadm.hr m.m.shkini Departm.nt of m.ning & m.tallurgical Engineering Amirkabir University of Technology Iranian Academ.c Center for Education Culture and Research (ACECR)Branch of Amirkabir

Bioleaching is an environm.ntally friendly m.thod for extraction of m.tal from.ores. In this study, bioleaching of copper oxide ore by Pseudom.nas aeruginosa was investigated. Pseudom.nas aeruginosa is a heterotrophic bacterm. that can produce various organic acids in an appropriate culture m.dium. and these acids can operate as leaching agents. The param.ters, such as particle size, glucose percentage in the culture m.dium. bioleaching tim., and solid/liquid ratio were optim.zed. Optim.m.bioleaching conditions were found as follows： particle size of 150-177 μm. glucose percentage of 6%, bioleaching tim. of 8 d, and solid/liquid ratio of 1：80. Under these conditions, 53% of copper was extracted.

关键词： copper ore treatm.nt copper oxides bioleaching organic acids heterotrophic bacteria Pseudom.nas aeruginosa

Num.rical and experim.ntal investigations of weld pool geom.try in GTA welding of pure alum.num

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Journal of Central South University 2014年第1期21卷 20-26页

作者： A.H.Faraji A.Bahm.ni m.Goodarzi S.H.Seyedein m.O.shabani Young Researchers Club Varamin-Pishva BranchIslamic Azad University m.terilal Science and Engineering Departm.nt Sharif University of Technology Departm.nt of m.tallurgy and m.terials Engineering Iran University of Science and Technology m.terials and Energy Research Center (m.RC)

A 2-D num.rical m.del was developed to predict the shape of weld pool in stationary GTA welding of com.ercial pure alum.nium. without considering fluid flow in the weld pool. A Gaussian current density and heat input distribution on the surface of the workpiece were considered. The param.ters of Gaussian distribution were m.dified by com.aring calculated results with experim.ntal ones. It was found that these distribution param.ters are fim.tions of applied current and arc length. Effects of arc length, applied current and welding tim. on the geom.try of the weld pool were investigated. To check the validity of the m.del, a series of experim.nts were also conducted. In general, the agreem.nt between calculated overall shape of the weld pool and the experim.ntal one was acceptable, especially in low applied currents. Therefore, it can be concluded that in pure alum.nium. the heat conduction is dom.nant m.chanism.of heat transfer in the weld pool.

关键词： num.rical m.del GTA welding pure alum.nium weld pool

REE Tetrad Effects in Rare-m.tal Granites

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Chinese Journal Of Geochem.stry 1993年第3期12卷 206-219页

作者：赵振华 AKIm.SA m.SUDA m.B.shabani nstitute of Geochem.stry(Guangzhou Branch) Academia SinicaGuangzhou510640 The present address:Departm.nt of Chem.stry The University of Electro-communicationsTokyoJapan Chem.stry Departm.nt Faculty of SciencesTokyo UniversityJapan

Described in this paper are the characteristics of tetrad effects of REE in rare-m.tal *** on the analytical data and experim.ntal geochem.cal data available,it is pointed out that the tetrad effects of REE in the granites are produced in the m.tal-fluid *** fractional crystallization of granitic m.lt(containing REE accessary m.nerals)and its interaction with volatile-rich(F,Cl)fluid are the m.jor factors leading to the tetrad effects of *** this,this paper presents a com.osite genetic m.del for high-degree fractional crystallization-volatile-rich fluid m.tasom.tism.of rare-m.tal *** the m.del,quantitative calculations have been ***,it is pointed out that the tetrad effects of REE can be used as an im.ortant indicator to distinguish m.neralized granites from.barren ones.

关键词：花岗岩稀土元素氟氯成因

Interevent tim.s estim.tion of m.jor and continuous earthquakes in Horm.zgan region based on radial basis function neural network

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Geodesy and Geodynam.cs 2016年第1期7卷 64-75页

作者： m.R.m.savi m.Kavei m.shabani Y.Hatem.Khani Departm.nt of Electrical Engineering Iran University of Science and Technology Departm.nt of Physics University of Hormozgan Departm.nt of Electrical Engineering University of Imam Khomeini Marine Sciences

This paper presents a new m.thod to estim.te the tim. of im.ortant earthquakes in Horm.zgan region with m.gnitude greater than 5.5 based on the Radial Basis Function （RBF） Neural Network （NN） m.dels. Input vector to the network is com.osed of different seisrnicity rates between m.in events that are calculated in convenient and reliable way to create optim.zed training m.thods. It helps network with a lim.ted num.er of training data to estim.tion. It is com.on for earthquakes m.deling by data-driven m.thods in this case. In addition, the proposed m.thod is com.ined with Rosenberg cluster m.thod to rem.ve aftershocks events from.the history of catalog for NN to better process the data. The results show that created RBF m.del successfully estim.tes the interevent tim.s between large and sequence earthquakes that can be used as a tool to predict earthquake, so that com.arison with other NN structure, for exam.le m.lti- Layer Perceptron （m.P） NN, reveals the superiority of the proposed m.thod. Because of superiority proposed m.thod has higher accuracy, lower costs and sim.ler network structure.

关键词： Interevent tim.sRadial basis functionNeural networksEarthquakes

Photoregulated or Energy Dependent Process of Horm.gonia Differentiation in Nostoc sphaeroides Kutzing （Cyanobacterium.

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Journal of Integrative Plant Biology 2005年第6期47卷 709-716页

作者： Dun-halli Lan-ZhouCHEN Gen-BaoLI Gao-HongWANG Li-RongSONG Yong-DingLIU StateKeyLaboratoryofFreshwaterEcologyandBiotechnology InstituteofHydrobiologytheChineseAcademyofSciencesWuhan430072China SchoolofResourceandEnvironm.ntSciences WuhanUniversityWuhan430072China

Horm.gonium. which was thought to play an im.ortant role in the dispersal and survival of these m.croorganism. in their natural habitats, is a distinguishable developm.ntal stage of heterocystous cyanobacteria. The present study exam.ned the effects of different light conditions and sugars on the differentiation ofNostoc sphaeroides Kiitzing to the horm.gonia stage. Results showed that differentiation of horm.gonia was light dependent in the absence of sugar, but that close to 100% of cyanobacteria differentiated to horm.gonia in the presence of glucose or sucrose, irrespective of the light conditions. This differentiation was inhibited, even in the presence of sugars, upon application of an inhibitor of respiration. Following the testing of different sugars, the effects of different lights were exam.ned. It was found that 5-10μm.l·m.-2·s^-1 photon flux density was optim.l for horm.gonia differentiation. One hundred percent differentiation was obtained with white light irradiation, in contrast with irradiation with green light (80% differentiation) and red light (0-10% differentiation). Although they showed different efficiencies in inducing horm.gonia differentiation in N. sphaeroides, the green and red radiation did not display antagonistic effects. When the additional aspect of tim. dependence was investigated through the application of different fight radiations and an inhibitor of protein synthesis, it was found that the initial 6 h of the differentiation process was crucial for horm.gonia differentiation. Taken together, these results show that horm.gonia differentiation in N. sphaeroides is either a photoregulated or an energy deoendent orocess.

关键词： cyanobacterium energy-dependent horm.gonia differentiation Nostoc sphaeroides Kützing photoregulation.

Application of a characterized difference-frequency laser source to carbon m.noxide trace detection

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Chinese Physics B 2012年第6期21卷 257-263页

作者： Alireza Khorsandi Zahra shabani m.nireh Ranjbar S. Ali Hoseinzadeh Salati Departm.nt of Physics University of Isfahan81746-73441 IsfahanIran

A tunable continuous wave（cw） m.d-infrared（m.R） laser based on difference-frequency generation（DFG） in a 1.5-cm.long AgGaS2 nonlinear crystal for trace gas detection is *** visible and near-infrared diode lasers were used as pum. and signal *** m.R-DFG laser was tunable in a wavelength range of 4.75 μm.4.88 μ*** phase-m.tching（Pm. condition was non-critically achieved by adjusting the tem.erature of the crystal for fixed pairs of input pum. and signal *** required Pm.tem.eratures of the generated m.R-DFG wavelengths have been calculated by using three sets of recent Sellm.ier equations and the tem.erature-dispersion equations of AgGaS2 given by Willer U,et al.（Willer U,Blanke T and Schade W 2001 ***.40 5439）.Then the calculated Pm.tem.eratures are com.ared with the experim.ntal *** perform.nce of the m.R-DFG laser is shown by the trace detection of the P（16） carbon m.noxide（12C16O） absorption line in a laboratory-fabricated absorption *** enhanced sensitivity of about 0.6×10 4 was obtained through the long path absorption provided by consecutive reflections between coated cylindrical m.rrors of a constructed cell.

关键词： difference-frequency generation AgGaS2 crystal m.lti-pass cell

Geant4 Com.arative Study of Affecting Different Param.ters on Optical Photons Related to the Plastic Scintillation Detector

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Journal of Physical Science and Application 2017年第6期7卷 43-50页

作者： m. Ebrahim. Shohani S. m. Golgoun m. Am.nipour A. shabani A. R. m.zoochi R. m.ghsoudi A. Olfateh S. m. Taheri m. R. Davarpanah Pars Isotope Com.any P. O. Box 14376-63181 Tehran Iran Radiation Application Research School Nuclear Science and Technology Research Institute P.O. Box 11365-3486 Tehran 1ran

In this research, different param.ters of plastic scintillator detector were investigated by Geant4 sim.lation toolkit. These param.ters consisted of radius, length and position of Pm. as well as surface reflective type and finish options. Furtherm.re, response tim. distributions of two organic plastic m.terials were studied. The results indicated that collecting optical photons has a linear relationship with Pm. radius head. Also, the vertical location of Pm. has a non-linear relationship with the optical photons collection. However, the collection decreased by increasing Pm. length or m.ving Pm. head horizontal position. The response functions of two plastic scintillator m.terials were in good agreem.nt with experim.ntal published results. Also, Geant4 radiation transport code can sim.late incident radiation photon and predict subsequent events to the Pm. head very well. The results indicated that BC-404 has faster scintillation properties versus BC-400 organic scintillator m.terials. Com.arison between Geant4 outputs illustrates that the best reflector m.terial and surface finish type for optical photons is ground TiO2.

关键词： Geant4 m.nte Carlo Code optical photon collection plastic scintillator reflector m.terial surface finish.