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Petroleum Science 2024年第2期21卷 951-961页

作者： amir Mohammad Zamani Ashkan Moslemi Kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

Cesium carbonate supported on hydroxyapatite coated Ni_(0.5)Zn_(0.5)Fe_2O_4 magnetic nanoparticles as an efficient and green catalyst for the synthesis of pyrano[2,3-c]pyrazoles

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Chinese Chemical Letters 2015年第5期26卷 575-579页

作者： Farid Moeinpour amir Khojastehnezhad Department of Chemistry Bandar Abbas BranchIslamic Azad University Young Researchers and Elite Club Mashhad BranchIslamic Azad University

Cesium carbonate supported on hydroxyapatite coated ***2O4 magnetic nanoparticles （***2O4@Hap-Cs2CO3） was found to be magnetically separable, highly efficient, green and recyclable heterogeneous catalyst. The synthesized nanocatalyst has been characterized with several methods （FT-IR, SEM, TEM, XRD and XRF） and these analyzes confirmed which the cesium carbonate is well supported to catalyst surface. After full characterization, its catalytic activity was investigated in the synthesis of pyranopyrazole derivatives and the reactions were carried out at room temperature in 50：50 water/ethanol with excellent yields （88-95%）. More importantly, the ***204@Hap-Cs2CO3 was easily separated from the reaction mixture by external magnetic field and efficiently reused at least six runs without any loss of its catalytic activity. Thus, the developed nanomagnetic base catalyst is potentially useful for the green and economic production of organic compounds.

关键词： Cesium carbonate Catalysis Pyranopyrazoles Magnetic nanoparticles Hydroxyapatite

Effect of Intermediate Annealing Temperature on Response of Repressing to Densification of Pre-Alloyed Cr-Mo Steel

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Journal of Iron and Steel Research International 2011年第2期18卷 52-56页

作者： amir Kalantari Maziyar Azadbeh Department of Materials Engineering Sahand University of Technology

Increasing density is one of the important factors for producing high quality powder metallurgy （PM） parts, which has beneficial effect on mechanical properties. One of the common techniques for achieving this goal is double compacting, which seems to be a potentially attractive method in PM route, also for Cr-Mo alloyed-steels. The objective of this research was to investigate the effect of first compacting pressure and intermediate annealing temperature on attaining higher densities and minimum interconnected porosity for Cr-Mo pre-alloyed steel. The effect of mentioned parameters was studied by measuring density, transverse rupture strength and macrohardness of repressed samples. The results show that for each first compacting pressure, the density range of repressed samples increases with the increasing annealing temperature up to a certain limit, due to C dissolution which causes free porosity and further densifieation. Annealing temperatures higher than optimum one should be avoided, since too much carbon dissolution results in harder and less deformable compacts. On the other hand, with regard to repressed density and other resulted properties, the amount of first compacting pressure offers considerable advantage in obtaining higher level of density and consequently improved mechanical properties.

关键词： double compacting repressed density repressed transverse rupture strength intermediate annealing temperature

Exact Solutions of Schrdinger Equation for the Position-Dependent Effective Mass Harmonic Oscillator

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Communications in Theoretical Physics 2014年第12期61卷 790-794页

作者： Naila amir Shahid Iqbal School of Natural Sciences National University of Sciences and Technology

A one-dimensional harmonic oscillator with position-dependent effective mass is studied. We quantize the oscillator to obtain a quantum Hamiltonian, which is manifestly Hermitian in configuration space, and the exact solutions to the corresponding Schr¨odinger equation are obtained analytically in terms of modified Hermite *** is shown that the obtained solutions reduce to those of simple harmonic oscillator as the position dependence of the mass vanishes.

关键词： nonlinear harmonic oscillator position-dependent effective mass system Schr¨odinger equation modified Hermite polynomials

On the Finiteness Dimension of Local Cohomology Modules

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Algebra Colloquium 2014年第3期21卷 517-520页

作者： Hero Saremi amir Marl Department of Mathematics Sanandaj Branch Islamic Azad University Sanandaj Iran Department of Mathematics University of Kurdistan Pasdaran St. P.O. Box 416 Sanandaj Iran

Let R be a commutative Noetherian ring, α an ideal of R, and M a non-zero finitely generated R-module. Let t be a non-negative integer. In this paper, it is shown that dim Supp Hi a（M） ≤ 1 for all i 〈 t if and only if there exists an ideal b of R such that dimR/b ≤ 1 and Hia（M） ≌ Hi b（M） for all i 〈 t. Moreover, we prove that dimSuppHia（M）〈≤dim M - i for all i.

关键词： local cohomology modules cofinite modules finiteness dimension

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 mild and highly efficient one-pot three-component reaction for carbon-sulfur bond formation catalyzed by potassium tert-butoxide

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Chinese Chemical Letters 2011年第10期22卷 1179-1182页

作者： Barahman Movassagh amir Rakhshani Department of Chemistry K.N.Toosi University of TechnologyP.O.Box 16315-1618TehranIran

Potassium tert-butoxide has been found to be a highly efficient catalyst for one-pot,three-component reaction of aryl aldehydes, acetophenones,and thiols via Claisen-Schmidt/Michael addition reactions for the synthesis of thia-Michael adducts in high yields. The reactions are best carried out in tert-butyl alcohol at room temperature.

关键词： Potassium tert-butoxide Thia-Michael adduct Three-component reaction C-S bond formation Thiols

On Non-standard Hilbert Functions

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Algebra Colloquium 2018年第1期25卷 71-80页

作者： amir Bagheri Rahim Rahmati-Asghar Marand Technical Coflege University of Tabriz Tabriz Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM) Department of Mathematics Faculty of Basic Sciences University of Maragheh

. Let S = k[x1,..., xn] be a non-standard polynomial ring over a field k and let M be a finitely generated graded S-module. In this paper, we investigate the behaviour of Hilbert function of M and its relations with lattice point counting. More precisely, by using combinatorial tools, we prove that there exists a polytope such that the image of Hilbert function in some degree is equal to the number of lattice points of this polytope.

关键词： polynomial ring non-standard Hilbert function Hermite normal form

Semi-active fuzzy control of Lali Cable-Stayed Bridge using MR dampers under seismic excitation

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 706-721页

作者： Sajad JAVADINASAB HORMOZABAD amir K GHORBANI-TANHA School of Civil Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Seismic control of cable-stayed bridges is of paramount importance due to their complex dynamic behavior,high flexibility,and low structural *** the present study,several semi-active Fuzzy Control Algorithms(FCAs)for vibration mitigation of Lali Cable-Stayed Bridge are *** demonstrate the efficiency of the algorithms,a comprehensive nonlinear 3-D model of the bridge is created using *** efficient method for connecting MATLAB and OpenSees is devised for applying FCAs to the structural model of the *** innovative fuzzy rulebases are introduced.A total of six different fiuzzy rule-bases are *** efficiency of the FCAs is evaluated in a comparative *** performance of fuzzy control systems is also compared with a sky-hook and a passive-on ***,the sensitivity of efficiency of control systems to the peak ground acceleration is evaluated *** addition,the effect of time lag is also *** study thoroughly examines the efficiency of the FCAs in different ***,the results can be regarded as a general guide to design semi-active fuzzy control systems for vibration mitigation of cable-stayed bridges.

关键词： semi-active control Fuzzy Control Algorithm cable-stayed bridge MR damper Lali Bridge

Toxoplasma, testosterone, and behavior manipulation： the role of parasite strain, host variations, and intensity of infection

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Frontiers in Biology 2014年第2期9卷 151-160页

作者： amir ABDOLI Department of Parasitology Faculty of Medical Sciences Kashan University of Medical Sciences Kashan lran Department Of Parasitology Faculty of Medical Sciences Tarbiat Modares ~Uni'versity Tehran Iran

Toxoplasma gondii is an intracellular parasite involved in the etiology of various behavioral and hormonal alterations in humans and rodents. Various mechanisms, including induction changes of testosterone production, have been proposed in the etiology of behavioral alterations during T. gondii infection. However, controversy remains about the effects of T. gondii infection on testosterone production; in some studies, increased levels of testosterone were reported, whereas other studies reported decreased levels. This is a significant point, because testosterone has been shown to play important roles in various processes, from reproduction to fear and behavior. This contradiction seems to indicate that different factors--primarily parasite strains and host variations--have diverse effects on the intensity of T. gondii infection, which consequently has diverse effects on testosterone production and behavioral alterations. This paper reviews the role of parasite strains, host variations, and intensity of T. gondii infection on behavioral alterations and testosterone production, as well as the role of testosterone in the etiology of these alterations during toxoplasmosis.

关键词： Toxoplasma gondii testosterone behavior manipulation parasite strain host variations intensity of infection,neurologic and psychiatric disorders