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Usage of Iranian scoria for copper and cadmium removal from aqueous solutions

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Journal of Central South University 2015年第10期22卷 3760-3769页

作者： Sara Seyfi amir reza azadmehr Mahdi Gharabaghi Abbas Maghsoudi Department of Mining & Metallurgical Engineering Amirkabir University of Technology School of Mining Engineering College of Engineering University of Tehran

The competitive removal of copper and cadmium from aqueous solutions using scoria has been investigated. Scoria was characterized by various methods, such as XRD, XRF, FT-IR and SEM. The results show that scoria sample contained augite, enstatite, diopside, and olivine. These minerals were separated from each other and each mineral was then subjected to the adsorption experiments. It was found that the main absorbent constituent in scoria was augite. Finally, statistical experimental method was used to optimization of adsorption conditions（Initial concentration of copper and cadmium ions, the amount of scoria and temperature） for removal of Cu（II） and Cd（II） ions from solution in optimum conditions. The optimum conditions are obtained as follows： concentrations of Cu（II） and Cd（II） of 400×10-6 and 554×10-6, respectively; amount of scoria of 7 g; temperature of 38 ℃. Under these conditions Cu（II） and Cd（II） ions are absorbed onto the scoria more than 79% and 16%, respectively.

关键词： scoria adsorption removal factorial design

Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-ANN approach

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 428-443页

作者： Hedye JALALI reza YEGANEH KHAKSAR Danial MOHAMMADZADEH S. Nader KARBALLAEEZADEH amir H.GANDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this study,the complex behavior of soil and a buried pipeline system subjected to a normal fault is analyzed by using an artificial neural network(ANN)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the ANN includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on biases and weights of the ANN *** results show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

Limb Lengthening and Reconstruction Society orthopedic surgeons in the United States:An analysis of geographical distribution,academic,leadership,and demographic characteristics

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World Journal of Orthopedics 2024年第2期15卷 147-155页

作者： amir Human Hoveidaei reza Niakan Seyed Hossein Hosseini-Asl Abijith Annasamudram Janet D Conway International Center for Limb Lengthening Rubin Institute for Advanced OrthopedicsSinai Hospital of BaltimoreBaltimoreMD 21215United States Student Research Committee Shiraz University of Medical SciencesShiraz 73Iran Students’Scientific Research Center Tehran University of Medical SciencesTehran ***Iran

BACKGROUND The Limb Lengthening and Reconstruction Society(LLRS)is a premier orthopedic specialty organization that promotes limb reconstruction for all *** membership characteristics,however,are poorly *** study delineates orthopedic surgeon LLRS members’demographic traits,academic achievement,leadership attainment,and geographical distribution across the United *** To inform aspiring orthopedic professionals,as well as to promote growth and diversity in both the LLRS organization and overarching *** This cross-sectional study examined United States LLRS members’academic,leadership,demographic,and geographical *** reviewing the 2023 LLRS member directory,Google search results were matched to the listings and appended to the compiled *** and ethnicity were evaluated visually utilizing retrieved *** Hirsch index(H-index)of academic activity,residency and fellowship training,other graduate degrees,leadership positions,practice type(academic or non-academic),and spoken languages were *** members per state and capita determined geographic *** Mann Whitney U test was applied to compare H-index between males and females,as well as to assess member differences pertaining to affiliation with academic vs non-academic practice *** The study included 101 orthopedic surgeons,78(77.23%)Caucasian and 23(22.77%)non-Caucasian,79(78.22%)male and 22(21.78%)*** with DO degrees comprised only 3.96%(4)of the cohort,while the vast majority held MDs[96.04%(97)].Mean H-index was 10.55,with male surgeons having a significantly higher score(P=0.002).Most orthopedic surgeons(88.12%,)practiced in academic *** those professionals who occupied leadership positions,14%were women,while 86%were ***,19(37.25%)United States regions and the District of Columbia lacked an LLRS-member orthopedic *** per capita rate across the United States was 0.30 LLRS orthopedic

关键词： Limb lengthening and reconstruction Orthopedic surgeon demographics Orthopedic surgeon societal membership Orthopedic fellowships

Comparative and Competitive Adsorption of Cu（II） and Cd（II） Using Scoria： Equilibrium, Kinetic and Thermodynamic Studies

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Chemical Research in Chinese Universities 2017年第3期33卷 471-478页

作者： SEYFI Sara azadmehr amir reza MAGHSOUDI Abbas Department of Mining & Metallurgical Engineering Amirkabir University of Technology Tehran *** Iran

Heavy metals, such as Cu（Ⅱ） and Cd（Ⅱ） are among the hazardous pollutants that lead to severe ecological problems and have a toxic effect on living organisms. This study was carried out on adsorption of Cu（Ⅱ） and Cd（Ⅱ） from single-and multi-component aqueous solutions with Iranian scoria. Two- and three-parameter isotherm models, such as Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Khan and Toth have been studied for single and bi- nary adsorption of Cu（Ⅱ） and Cd（Ⅱ） onto scoria. The best result was attained from Langmuir model for Cu（Ⅱ） and Cd（Ⅱ） ions in single and binary solution. Therefore, homogenous adsorption is dominated, which was emphasized by three-parameter isotherm models. Based on the value of the free energy of adsorption for Cu（Ⅱ） and Cd（Ⅱ）, the inte-raction between these ions and scoria is a physical adsorption. In order to investigate competitive adsorption behavior, modified and extended Langmuir and Freundlich models have been studied, which indicated that adsorption of Cu（Ⅱ） and Cd（Ⅱ） on scoria has synergistic behavior. Extended Freundlich model and modified Langmuir model described Cu（Ⅱ） and Cd（Ⅱ） adsorption onto scoria, respectively.

关键词： Adsorption Individual isotherm Multi-component isotherm Kinetics Thermodynamic

Effect of synthesis solution pH of Co/γ-Al_2O_3 catalyst on its catalytic properties for methane conversion to syngas

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燃料化学学报 2018年第3期46卷 311-318页

作者： amir Mosayebi reza Abedini Department of Chemical Engineering Tafresh University Faculty of Chemical Engineering Babol Noshirvani University of Technology

The cobalt nanoparticles over γ-Al_2O_3 support were prepared via chemical reduction of CoCl_2·6H_2O using NaBH_4 with various values of pH in the range of 11. 92-13. 80. Synthesized catalysts were studied through X-ray diffraction( XRD),N_2 adsorption/desorption( BET),H_2-temperature programmed reduction( H_2-TPR),H_2-chemisorption,O_2 pulse titration and temperature programmed oxidation( TPO) methods. Obtained results exhibited the synthesis solution pH showed a significant influence on the activity and selectivity in partial oxidation of methane reaction. The methane conversion,CO selectivity and H_2 yield were enhanced by increasing of the synthesis solution pH. Compared to other catalysts,the catalyst that synthesized at pH of 13.80,showed a superior ability in syngas production with a H_2/CO ratio of near 2 and also a proper stability against deactivation during the partial oxidation of methane.

关键词：部分氧化 Co/-Al 2 O 3 nanoparticles 选择 pH 价值

3D numerical parametric study of the influence of open-pit mining sequence on existing tunnels

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International Journal of Mining Science and Technology 2017年第3期27卷 459-466页

作者： Beyabanaki amir reza Gall Vojtech McMillen Jacobs Associates San Francisco CA 94105 USA Gall Zeidler Consultants Ashburn VA 20147 USA

The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence on existing tunnels such as displacements of the lining and additional loads on the lining. In this paper, three-dimensional numerical parametric study is performed to explore this complex interaction. This study investigates the effects of different parameters that may affect the tunnel response. These parameters are： excavation sequence method, horizontal/vertical stress ratio, slope angle, and tunnel diameter. This study shows that the mining sequence affects the stability of the tunnels. The open-pit mining activities lead to both higher axial forces in rock bolts and normal forces and bending moments in the lining. The results of the analysis also demonstrate that the mining sequence causes tunnel heave and significant tensile forces in the lining. Based on the study in this paper a better understanding of the interaction between oDen-oit minin~ seouence and tunnels will he ohtained

关键词： Three-dimensionalNumerical parametric studyExisting tunnelOpen-pit mining sequenceModeling

CHARACTEIZATIONS OF WOVEN g-FRAMES AND WEAVING g-FRAMES IN HILBERT SPACES AND C*-MODULES

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Acta Mathematica Scientia 2023年第6期43卷 2471-2482页

作者： amir KHOSRAVI Mohammad reza FARMANI Faculty of Mathematical Sciences and Computer Kharazmi University

In this paper,using Parseval frames we generalize Sun’s results to g-frames in Hilbert C*-***,for g-frames in Hilbert spaces,we present some characterizations in terms of a family of frames,not only for orthonormal ***,we have a note about a comment and a relation in the proof of Proposition 5.3 in [*** et al.,On weaving g-frames for Hilbert spaces,Complex Analysis and Operator Theory,2020].Finally,we have some results for g-Riesz bases,woven and P-woven g-frames.

关键词： g-frame fusion frame woven frame Riesz basis g-Riesz basis 46L99 42C15 46H25

Evaluation on the Two Filling Functions for the Recovery of Forest Information in Mountainous Shadows on Landsat ETM + Image

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Journal of Mountain Science 2011年第3期8卷 414-426页

作者： SHAHTAHMASSEBI amir reza MOORE Nathan Institute of Agriculture Remote Sensing and Information Technology Zhejiang University Key Laboratory of Agricultural Remote Sensing and Information System of Zhejiang Province Department of Geography Michigan State University

In general,topographic shadow may reduce performance of forest mapping over mountainous regions in remotely sensed *** this paper,information in shadow was synthesized by using two filling techniques,namely,roifill and imfill,in order to improve the accuracy of forest mapping over mountainous *** two methods were applied to Landsat Enhanced Thematic Mapper (ETM +) multispectral image from Dong Yang County,Zhejiang Province,*** performance of these methods was compared with two conventional techniques,including cosine correction and multisource *** results showed that by applying filling approaches,average overall accuracy of classification was improved by 14 ***,through conventional methods this value increased only by 9 *** results also revealed that estimated forest area on the basis of shadow-corrected images by 'roifill' technique was much closer to the survey data compared to traditional *** from this finding,our finding indicated that topographic shadow was an accentuated problem in medium resolution images such as Landsat ETM+ over mountainous regions.

关键词： Shadow Imfill: Roifill: Landsat ETM+

A 3D analytical model for vortex velocity field based on spiral streamline pattern

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Water Science and Engineering 2019年第3期12卷 244-252页

作者： Maryam Azarpira amir reza Zarrati Department of Civil and Environmental Engineering Amirkabir University of Technology

Vortices that develop over intakes are a hazardous hydraulic *** this study, a 3D model was developed to study the flow field in air-core *** model is based on the spiral pattern of streamlines and the analytical solution of the momentum and continuity equations for deriving the three components of *** model provides equations for free surface profiles and 3D patterns of the ***, a new relationship was suggested for calculating effective viscosity and its distribution across the vortex flow *** performance of the proposed analytical model was compared with existing experimental data and the results of previous analytical *** outcomes indicated that the proposed model could predict characteristics of the vortex flow with good accuracy.

关键词： Air-core vortices Analytical model Velocity distribution Spiral streamlines Free surface profile