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Chinese Chemical Letters 2015年第1期26卷 160-166页

作者： Mohammad hossein Mashhadizadeh Rasoul Pourtaghavi Talemi Faculty of Chemistry Kharazmi(Tarbiat Moallem)University

An effective procedure for constructing a DNA biosensor is developed based on covalent immobilization of NH2 labeled,single strand DNA（NH2-ssDNA） onto a self-assembled diazo-thiourea and gold nanoparticles modified Au electrode（diazo-thiourea/GNM/Au）.Gold nano-particles expand the electrode surface area and increase the amount of immobilized thiourea and single stranded DNA（ssDNA） onto the electrode ***-thiourea film provides a surface with high conductibility for electron transfer and a bed for the covalent coupling of NH2-ssDNA onto the electrode *** immobilization and hybridization of the probe DNA on the modified electrode is studied by differential pulse voltammetry（DPV） using methylene blue（MB） as a well-known electrochemical hybridization *** linear range for the determination of complementary target ssDNA is from 9.5（±0.1） × 10^-13 mol/L to1.2（±0.2） x 10^-9 mol/L with a detection limit of 1.2（±0.1）〉 10^-13 mol/L.

关键词： DNA biosensor Gold nano-particles Thiourea Methylene blue

New thermally stable polyesters based on 2,5-pyridinedicarbonyl dichloride and aromatic diols:Synthesis and characterization

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Chinese Chemical Letters 2009年第7期20卷 885-888页

作者： hossein Nasr Isfahani Khalil Faghihi Faculty of Chemistry Shahrood University of TechnologyShahroodIran Organic Polymer Chemistry Research Laboratory Department ofChemistryFaculty ofScienceArak UniversityArak 38156 Iran

Six new thermally stable polyesters （4a-f） were synthesized through the solution polycondensation reaction of 2,5-pyridine dicarbonyldichloride （2） with six aromatic diols in N,N＇-dimethyl acetamide （DMAc） solution and in the presence of pyridine as a base. The polycondensation reactions produce a series of new polyesters （4a-f） in high yields, and inherent viscosity between 0.30 and 0.55 dL/g. The resulting polyesters were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis （TGA and DTG）, solubility test, Fourier transform infrared （FT-IR） spectroscopy and gel permeation chromatography （GPC）. C 2009 Khalil Faghihi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： High performance polymers Polyesters Pyridyl moiety

Evaluating and modeling the spatiotemporal pattern of regional-scale salinized land expansion in highly sensitive shoreline landscape of southeastern Iran

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Journal of Arid Land 2018年第6期10卷 946-958页

作者： Mohammad SHAFIEZADEH hossein MORADI Sima FAKHERAN Department of Natural Resources Isfahan University of Technology

Taking an area of about 2.3×10~4 km~2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and 2015 were acquired as the main source of data. Radiometric, atmospheric and cutline blending methods were used to improve the quality of images and help better classify salinized land areas under the support vector machine method. A set of landscape metrics was also employed to detect the spatial pattern of salinized land expansion from 1986 to 2015. Four factors including distance to sea, distance to sea water channels, slope, and elevation were identified as the main contributing factors to land salinization. These factors were then integrated using the multi-criteria evaluation (MCE) procedure to generate land sensitivity map to salinization and also to calibrate the cellular-automata (CA) Markov chain (CA-Markov) model for simulation of salt-affected lands up to 2030, 2040 and 2050. The results of this study showed a dramatic dispersive expansion of salinized land from 7.7 % to 12.7% of the total study area from 1986 to 2015. The majority of areas prone to salinization and the highest sensitivity of land to salinization was found to be in the southeastern parts of the region. The result of the MCE-informed CA-Markov model revealed that 20.3% of the study area is likely to be converted to salinized lands by 2050. The findings of this research provided a view of the magnitude and direction of salinized land expansion in a past-to-future time period which should be considered in future land development strategies.

关键词： soil salinization remote sensing CA-Markov salt land expansion southeastern Iran

GIS-based ordered weighted averaging and Dempster-Shafer methods for landslide susceptibility mapping in the Urmia Lake Basin, Iran

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International Journal of Digital Earth 2014年第8期7卷 688-708页

作者： Bakhtiar Feizizadeh Thomas Blaschke hossein Nazmfar Department of Physical Geography Centre for Remote Sensing and GISUniversity of TabrizTabrizIran Department of Geoinformatics(Z_GIS) University of SalzburgSalzburgAustria Department of Geography and Urban Planning University of Mohaghegh ArdabiliArdabilIran

In this paper,GIS-based ordered weighted averaging(OWA)is applied to landslide susceptibility mapping(LSM)for the Urmia Lake Basin in northwest *** landslide causal factors were used,whereby the respective parameters were extracted from an associated spatial *** factors were evaluated,and then the respective factor weight and class weight were assigned to each of the associated factors using analytic hierarchy process(AHP).A landslide suscept-ibility map was produced based on OWA multicriteria decision *** order to validate the result,the outcome of the OWA method was qualitatively evaluated based on an existing inventory of known ***,an uncertainty analysis was carried out using the Dempster-Shafer *** on the results,very strong support was determined for the high susceptibility category of the landslide susceptibility map,while strong support was received for the areas with moderate *** this paper,we discuss in which respect these results are useful for an improved understanding of the effectiveness of OWA in LSM,and how the landslide prediction map can be used for spatial planning tasks and for the mitigation of future hazards in the study area.

关键词： GIS-multicriteria decision analysis OWA uncertainty analysis belief landslide susceptibility mapping Urmia Lake Basin

How much would silica nanoparticles enhance the performance of low-salinity water flooding?

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Petroleum Science 2019年第3期16卷 591-605页

作者： Amir hossein Saeedi Dehaghani Reza Daneshfar Department of Petroleum Engineering Faculty of Chemical Engineering Tarbiat Modares University Jalal Ale Ahmad Highway Gisha Bridge Tehran Iran Department of Petroleum Engineering Ahwaz Faculty of Petroleum Engineering Petroleum University of Technology (PUT) Ahwaz Iran

Nanofluids and low-salinity water(LSW)flooding are two novel techniques for enhanced oil *** some efforts on investigating benefits of each method,the pros and cons of their combined application need to be *** work sheds light on performance of LSW augmented with nanoparticles through examining wettability alteration and the amount of incremental oil recovery during the displacement *** this end,nanofluids were prepared by dispersing silica nanoparticles(0.1 wt%,0.25 wt%,0.5 wt% and 0.75 wt%)in 2,10,20 and 100 times diluted samples of Persian Gulf *** angle measurements revealed a crucial role of temperature,where no wettability alteration occurred up to 80 ℃.Also,an optimum wettability state(with contact angle 22°)was detected with a 20 times diluted sample of seawater augmented with 0.25 wt% silica ***,extreme dilution(herein 100 times)will be of no *** micromodel flooding,it was found that in an oil-wet condition,a combination of silica nanoparticles dispersed in 20 times diluted brine had the highest displacement efficiency compared to silica nanofluids prepared with deionized ***,by comparing oil recoveries in both water-and oil-wet micromodels,it was concluded that nanoparticles could enhance applicability of LSW via strengthening wettability alteration toward a favorable state and improving the sweep efficiency.

关键词： Low-salinity water Silica nanoparticles Low-salinity nanofluid Micromodel Enhanced oil recovery Wettability alteration

Probing the Lambda-DGP Braneworld model

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Research in Astronomy and Astrophysics 2016年第9期16卷 31-38页

作者： Arvin Ravanpak hossein Faraiollahi Golnaz Fadakar Department of Physics Vali-e-Asr University Rafsanjan Iran Department of Physics University of Guilan Rasht Iran School of Physics University of New South Wales Sydney NSW 2052 Australia

We study cosmic dynamics in the context of the normal branch of the DGP braneworld model. Using current Planck data, we find the best fitting model and associated cosmological parameters in non-fiat ADGP. With the transition redshift as a basic variable and statefinder parameters, our result shows that the Universe starts its accelerated expansion phase slightly earlier than expected in ACDM cosmology. The result also alleviates the coincidence problem of the ACDM model.

关键词： (cosmology:) cosmological parameters -- observations -- theory -- dark energy -- methods numerical

Computation of the structure of a magnetized strange quark star

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Research in Astronomy and Astrophysics 2011年第7期11卷 851-862页

作者： Gholam hossein Bordbar Ali Reza Peivand Department of Physics Shiraz University Research Institute for Astronomy and Astrophysics of Maragha Department of Physics Tafresh University

We have calculated some properties of spin polarized strange quark matter（SQM） in a strong magnetic field at zero temperature using the MIT bag *** showed that the equation of state of spin polarized SQM is stiffer than that for unpolarized *** have also computed the structural properties of a spin polarized strange quark star（SQS） and found that the presence of a magnetic field leads to a more stable SQS when compared to the structural properties of an unpolarized SQS.

关键词： dense matter—equation of state—magnetic field

Optimization of the fully grouted rock bolts for load transfer enhancement

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International Journal of Mining Science and Technology 2015年第5期25卷 707-712页

作者： Ghadimi Mostafa Shahriar Korosh Jalalifar hossein Department of Mining Engineering Tehran Science and Research BranchIslamic Azad University Faculty of Mining Metallurgy and Petroleum EngineeringAmir Kabir University of Technology Department of Petroleum and Mining Engineering Environmental and Energy Research CenterShahidBahonar University of Kerman

The purpose of this study is to investigate the role of bolt profile configuration in load transfer capacity between the bolt and ***,five types of rock bolts are used with different *** rock bolts are modeled by ANSYS *** show that profile rock bolt T_3 and T_ with load capacity 180 and 195 kN in the jointed rocks,are the optimum ***,the performances of the selected profiles are examined in Tabas Coal Mine by FLAC *** is good subscription between the results of numerical modeling and instrumentation reading such as tells tale,sonic extensometer and strain gauge rock *** to the finding of this study,the proposed pattern of rock bolts,on 7 + 6 patterns per meter with 2 flexi bolt(4 m) for support gate road.

关键词： Fully grouted rock bolts Numerical modeling Load transfer Bolt profile

QUASI-PERMUTATION REPRESENTATIONS OF ALTERNATING AND SYMMETRIC GROUPS

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Acta Mathematica Scientia 2007年第2期27卷 297-300页

作者： Houshang Behravesh Mohammad hossein Jafari Department of Mathematics University of Urmia UrmiaIran Department of Mathematics University of Tabriz TabrizIran

The quantities c（G）, q（G） and p（G） for finite groups were defined by H. Behravesh. In this article, these quantities for the alternating group An and the symmetric group Sn are calculated. It is shown that c（G... 详细信息

关键词： Quasi-permutation representations alternating groups symmetric groups character theory

Parametric Study of Hip Fracture Risk Using QCT-Based Finite Element Analysis

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Computers, Materials & Continua 2022年第4期71卷 1349-1369页

作者： hossein Bisheh Yunhua Luo Timon Rabczuk Department of Mechanical Engineering University of ManitobaWinnipegR3T 5V6Canada Institute of Structural Mechanics Bauhaus-Universität WeimarWeimar99423Germany Department of Biomedical Engineering University of ManitobaWinnipegR3T 5V6Canada

Various parameters such as age,height,weight,and body mass index(BMI)influence the hip fracture risk in the elderly which is the most common injury during the sideways *** paper presents a parametric study of hip fracture risk based on the gender,age,height,weight,and BMI of subjects using the subject-specific QCT-based finite element modelling and simulation of single-leg stance and sideways fall *** fracture risk is estimated using the strain energy failure criterion as a combination of bone stresses and strains leading to more accurate and reasonable results based on the bone failure *** the effects of various parameters on hip fracture risk can help to prescribe more accurate preventive and treatment plans for a community based on the gender,age,height,weight,and BMI of the *** of this study show an increase in hip fracture risk with the increase of age,body height,weight,and BMI in both women and men under the single-leg stance and the sideways fall configurations.

关键词： Hip fracture risk finite element model strain energy parametric study