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Inverse Stone-Thrower-Wales defect and transport properties of 9AGNR double-gate graphene nanoribbon FETs

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Journal of Central South University 2019年第11期26卷 2943-2952页

作者： Mohammad Bagher NASROLLAHNEJAD Parviz keshavarzi Electrical and Computer Engineering Department Semnan University

Defect-based engineering of carbon nanostructures is becoming an important and powerful method to modify the electron transport properties in graphene nanoribbon FETs. In this paper, the impact of the position and symmetry of the ISTW defect on the performance of low dimensional 9AGNR double-gate graphene nanoribbon FET (DG-GNRFET) is investigated. Analyzing the transmission spectra, density of states and current-voltage characteristics shows that the defect effect on the electron transport is considerably varied depending on the positions and the orientations (the symmetric and asymmetric configuration) of the ISTW defect in the channel length. Based on the results, the asymmetric ISTW defect leads to a more controllability of the gate voltages over drain current, and drain current increases more than 5 times. The results have also con rmed the ISTW defect engineering potential on controlling the channel electrical current of DG-AGNR FET.

关键词： inverse Stone-Thrower-Wales defect electronic transport properties graphene nanoribbon tight binding NEGF formalism

Nonlinear vibration analysis of a rotor supported by magnetic bearings using homotopy perturbation method

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Propulsion and Power Research 2017年第3期6卷 223-232页

作者： Aboozar Heydari Mina Mirparizi Farshad Shakeriaski Farhad Sheykh Samani Mohamadreza keshavarzi National Iranian Oil Company Iran Shahid Bahonar University of Kerman KermanIran University of Yazd YazdIran University of Sistan and Baluchestan ZahedanIran

In this paper,the effects of nonlinear forces due to the electromagnetic field of bearing and the unbalancing force on nonlinear vibration behavior of a rotor is *** rotor is modeled as a rigid body that is supported by two magnetic bearings with eightpolar *** governing dynamics equations of the system that are coupled nonlinear second order ordinary differential equations(ODEs)are derived,and for solving these equations,the homotopy perturbation method(HPM)is *** applying HPM,the possibility of presenting a harmonic semi-analytical solution,is *** fact,with equality the coefficient of auxiliary parameter(p),the system of coupled nonlinear second order and non-homogenous differential equations are obtained so that consists of unbalancing *** considering some initial condition for displacement and velocity in the horizontal and vertical directions,free vibration analysis is done and next,the forced vibration analysis under the effect of harmonic forces also is ***,various parameters on the vibration behavior of rotor are *** in amplitude and response phase per excitation frequency are *** show that by increasing excitation frequency,the motion amplitude is also increases and by passing the critical speed,it *** it shows that the magnetic bearing system performance is in stable maintenance of *** parameters affecting on vibration behavior,has been studied and by comparison the results with the other references,which have a good precision up to 2nd order of embedding parameter,it implies the accuracy of this method in current research.

关键词： Nonlinear vibration behavior Rotor Magnetic bearing Unbalancing force Coupled nonlinear second order equations homotopy perturbation

Using fuzzy-AHP and parametric technique to assess soil fertility status in Northeast of Iran

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Journal of Mountain Science 2020年第4期17卷 931-948页

作者： Ali keshavarzi Henry Oppong TUFFOUR Ali BAGHERZADEH Leo Paapa TATTRAH Vinod KUMAR Amin GHOLIZADEH Jesús RODRIGO-COMINO Laboratory of Remote Sensing and GIS Department of Soil ScienceUniversity of TehranKaraj 31587-77871Iran Department of Mining Engineering Hacettepe University06800 BeytepeAnkaraTurkey Department of Crop and Soil Sciences Kwame Nkrumah University of Science and TechnologyKumasi 00233Ghana Department of Agriculture Islamic Azad UniversityMashhad BranchP.O.Box:91735-413Mashhad 91735-413Iran Department of Computer Science Kumasi Technical UniversityKumasi 00233Ghana Government Degree College Ramban-182144 Jammu and KashmirIndia Physical Geography Trier University54286 TrierGermany Soil Erosion and Degradation Research Group.Department of Geography Valencia UniversityBlasco Ibànez2846010 ValenciaSpain

A good understanding of the levels and distribution patterns of soil properties and/or quality indicators is a prerequisite for developing sustainable agricultural land management programs. Traditional assessments of these parameters of soil fertility status are somewhat costly, in both economics and time aspects. Different modelling techniques have been proposed as a useful tool for determination of soil quality indicators and development of soil fertility maps, but to what extent these results are reliable remains under-quantified in many regions worldwide. To address this uncertainty, Fuzzy-Analytical Hierarchy Process(Fuzzy-AHP) and Parametric analyses were conducted to ascertain the soil fertility status of a semiarid region in the Northeast of Iran for some selected crops: alfalfa, corn silage, potato, sugar beet, tomato and wheat. The Fuzzy-AHP and Parametric techniques using soil suitability indices were estimated for each crop and each soil delineation was achieved by Ordinary Kriging. The Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS) was used as a compensatory method to allow tradeoffs among the selected criteria. Our results demonstrated that from the Fuzzy-AHP analysis, the soil fertility indices ranged from moderate to high for production of alfalfa;from low to high for production of corn silage and sugar beet;moderate to high for production of potato and tomato;and from low to moderate for production of wheat. However, the parametric analysis showed soil fertility classes ranging from very low to high for production of all the selected crops. High correlations were also observed between soil fertility indices predicted by both models. Similarly, the capacities of both models to predict soil fertility status for production of the selected crops were also highly correlated. The preference for the cultivation of the selected crops based on the Fuzzy-AHP analysis was sugar beet > corn silage > wheat > alfalfa > tomato > potato.

关键词： Soil fertility Agricultural land management Parametric model Geographic information systems Analytic Hierarchy Process

Radiolabeled FMLF a Valuable Peptide for Diagnostic Imaging

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Journal of Pharmacy and Pharmacology 2014年第1期2卷 70-78页

作者： Fatemeh keshavarzi Parviz Ashtari Department of Biology Sanandaj Branch Islamic Azad University Sanandaj Kurdistan 66169-35391 lran Radiation Application Research School Nuclear Science & Technology Research Institute Tehran 14399-51113 Iran

Molecular imaging techniques are increasingly being used in the localization of disease, the staging of disease and for therapy control. The objective of current study focused on the optimization of synthesis, quality control, in vitro and in vivo evaluation of 123I radiopharmaceuticals based on the chemotactic peptide N-formyl-Met-Leu-Phe. Labeling studies were done both by direct method using chloramine-Y according to Khawli （1989） and indirect method using [125I and 131I] S1B according to Zalutsky （1987）. Then, biodistribution studies were performed both in normal mice and the one bearing 50 laL turpentine for 24h, promoted inflammation in right leg. Furthermore, the ability of the labeled peptide conjugate to bind to human polymorph nuclear leukocytes was determined using in vitro assay. With increasing in pl-l, yield of labeled FMLF （N-formyl-Met-Leu-Phe） decreased perhaps because of interaction OH to carboxyl group of SIB. The maximum activity was observed in the right leg which injected with turpentine due to infection and increase in blood circulation. Also, this peptide was conjugated to PMN （Poly morph nuclear） specifically and maximum activity was 66%. The highest absorption of FLMF was seen in kidney, liver, stomach and gut. The small size of this protein causes passing through the glomerular of kidney, so high activity was observed in urine and bladder.

关键词： Molecular imaging FLMF radiolabeled peptide.

Misleading Communication VS. Effective Aviation Management

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Intelligent Information Management 2011年第6期3卷 240-243页

作者： keshavarzi Zahra 不详

In this paper some of the important problems and issues such as human and communication errors in safety and civil aviation management are presented. The problems arise from misleading information from different sources. To avoid the above problems, a centralization of the information is proposed here. To centralize the information for Air Traffic Management (ATM), a mining data routing system called SCADA (Supervisory Control and Data Acquisition) system is suggested in this study. The utilization of SCADA system will helps to capture air traffic information and aircraft data via satellite technology and transfer it to data mining center and then to central organization. The stored digital data will exchange the information between different organizations and will be used by management systems. The stored reliable information helps to make an appropriate decision in the Air Traffic Management system.

关键词： Communication Errors Civil Aviation Civil Aviation Management SCADA System

Total phenolic,chromium contents and antioxidant activity of raw and processed sugars

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Information Processing in Agriculture 2017年第1期4卷 83-89页

作者： Munawar Iqbal MAfzal Qamar Tanveer H.Bokhari Mazhar Abbas Fida Hussain Nasir Masood Ali keshavarzi Naseem Qureshih Arif Nazir Department of Chemistry The University of LahoreLahorePakistan Government Postgraduate College Samanabad FaisalabadPakistan Department of Chemistry Government College UniversityFaisalabad 38000Pakistan Institute of Molecular Biology and Biotechnology The University of LahoreLahorePakistan Department of Botany Qurtuba University of Science and Information TechnologyPeshawar 25100Pakistan Department of Environmental Sciences COMSATS Institute of Information TechnologyVehari 61100Pakistan Laboratory of Remote Sensing and GIS Department of Soil Science EngineeringUniversity of TehranKaraj 31587-77871Iran Department of Chemistry Karakoram International UniversityGilgit 15100Pakistan

Processing improves the visual quality of food;however,the ingredient and nutritional values may *** present study,the sugar samples(refined,raw,gur(Jaggery/jaggeree)and molasses)were collected from 20 different agro-climatic regions of Pakistan and analyzed for the chromium concentration,total phenolic and antioxidant activity,in order to evaluate the processing *** concentration of Cr was determined by digestion method using atomic absorption spectrophotometer,while antioxidant activity was determined by DPPH(1,1-diphenyl-2-picrylhydrazyl)and reducing *** was observed that chromium content in Jaggery was 74%higher than raw sugar,while molasses showed 21.27%higher concentration versus *** total phenolic contents were found considerably higher in molasses(3751 lg GAE/g)followed by Jaggery(3285 lg GAE/g),raw sugar(27.75 lg GAE/g)and refined sugar(23.81 lg GAE/g).The DPPH scavenging activity and reducing power was also found dependent to sugar *** results,it can be concluded that processing significantly affected the chromium contents,total phenolics and antioxidant activity.

关键词： Processing effect Sugars Total phenolics Antioxidant activity Chromium contents Diabetes mellitus

THE EFFECT OF STRENGTHENING EXERCISE ON DOMINANT AND NONDOMINANT LEG

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THE EFFECT OF STRENGTHENING EXERCISE ON DOMINANT AND NONDOMI...

Wafer-level vapor cells filled with laser-actuated hermetic seals for integrated atomic devices

The 2004 Pre-Olympic Congress

作者： keshavarzi Hamidreza Islamic Azad University Eslamshahr Iran

＜正＞Introduction purpose Physical reconditioning is thought to be an important treatment modality for athletes with lower extermity injuries particulary reconditioning of specific atrophied *** lower extermities are subject to atrophied muscles secondary to avoiding physical activity in an attempt to decrease their ***,in turn,results in more,

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Microsystems & Nanoengineering 2022年第6期8卷 225-235页

作者： Vincent Maurice Clément Carlé Shervin keshavarzi Ravinder Chutani Samuel Queste Ludovic Gauthier-Manuel Jean-Marc Cote Rémy Vicarini Moustafa Abdel Hafiz Rodolphe Boudot Nicolas Passilly IEMN-Institut d’Electronique de Microélectronique et de Nanotechnologie UMR8520 CNRSUniversitéLilleCentrale LilleF-59000 LilleFrance FEMTO-ST Institute UMR6174 CNRSUniversitéBourgogne Franche-ComtéF-25030 BesançonFrance

Atomic devices such as atomic clocks and optically-pumped magnetometers rely on the interrogation of atoms contained in a cell whose inner content has to meet high standards of purity and ***-blowing techniques and craftsmanship have evolved over many decades to achieve such standards in macroscopic vapor *** the emergence of chip-scale atomic devices,the need for miniaturization and mass fabrication has led to the adoption of microfabrication techniques to make millimeter-scale vapor ***,many shortcomings remain and no process has been able to match the quality and versatility of glass-blown ***,we introduce a novel approach to structure,fill and seal microfabricated vapor cells inspired from the century-old approach of glass-blowing,through opening and closing single-use zero-leak microfabricated *** valves are actuated exclusively by laser,and operate in the same way as the“make-seals”and“break-seals”found in the filling apparatus of traditional *** structures are employed to fill cesium vapor cells at the *** make-seal structure consists of a glass membrane that can be locally heated and deflected to seal a *** break-seal is obtained by breaching a silicon wall between *** new approach allows adapting processes previously restricted to glass-blown *** can also be extended to vacuum microelectronics and vacuum-packaging of micro-electro-mechanical systems(MEMS)devices.

关键词： filled vacuum heated

Experimental Study of the Effects of Submerged Dikes on the Energy and Momentum Coefficients in Compound Channel

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Engineering（科研） 2010年第11期2卷 855-862页

作者： Alireza keshavarzi Mehdi Valizadeh James Ball 不详

This paper aims to understand the flow structure around submerged dike in the main channel and flood plain of a compound cross section. The study undertaken to develop this understanding was carried out in a laboratory flume using a submerged vane installed at a 90 degree angle to the bank. In order to study the flow structures, the flow velocity was measured using a three-dimensional Acoustic Doppler Velocity meter (micro-ADV) with data collection rate of 50 Hz. These flow velocity measurements were taken at 500 points on a regular grid. As the tests were undertaken with turbulent flow, these conditions were subcritical. Furthermore, all the tests were undertaken using a fixed bed. The results obtained showed that the momentum transfer and the kinetic energy reduced in two directions. Also the energy and momentum coefficients decreased significantly with the installation of the submerged vane inside the main channel. Finally, streamlines were found to deviate from the side walls of channel into the main channel.

关键词： Submerged Vane Flow Structure Compound Channel Velocity Meter (Micro-ADV)