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Spin-valley Hall conductivity of doped ferromagnetic silicene under strain

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Chinese Physics B 2017年第1期26卷 410-416页

作者： bahram Shirzadi Mohsen Yarmohamma.i Department of Physics Razi University Kermanshah Iran Young Researchers and Elite Club Kermanshah Branch Islamic Azad University Kermanshah Iran

The spin-valley Hall conductivity（SHC-VHC） of two-dimensional material ferromagnetic graphene＇s silicon analog,silicene, is investigated in the presence of strain within the Kubo formalism in the context of the Kane–Mele *** Dirac cone approximation has been used to investigate the dynamics of carriers under the strain along the armchair（AC） direction. In particular, we study the effect of external static electric field on these conductivities under the *** the presence of the strain, the carriers have a larger effective mass and the transport decreases. Our findings show that SHC changes with respect to the direction of the applied electric field symmetrically while VHC increases ***, the reflection symmetry of the structure has been broken with the electric field and a phase transition occurs to topological insulator for strained ferromagnetic silicene. A critical strain is found in the presence of the electric field around 45%. SHC（VHC） decreases（increases） for strains smaller than this value symmetrically while it increases（decreases） for strains larger than one.

关键词： ferromagnetic silicene Kubo formalism strain spin-valley conductivity

Determination of Vanadyl Porphyrins by Liquid-liquid Microextraction and Nano-baskets of p-tert-Calix[4]arene Bearing Di-[N-(X)sulfonye Carboxamide] and Di-(1-propoxy) in Ortho-cone Conformation

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Chemical Research in Chinese Universities 2012年第5期28卷 807-813页

作者： MOKHTARI bahram POURABDOLLAH Kobra Razi Chemistry Research Center(RCRC) Shahreza Branch Islamic Azad University

Dispersive liquid-liquid microextraction technique was introducd to remove the centrifuging step and conduct inclusion microextraction of charged porphyrins by nano-baskets. For nano-baskets of p-tert-calix[4]arene bearing di-[N-（X）sulfonyl carboxamide] and di-（1-propoxy） in ortho-cone conformation was synthesized and used. The related parameters including ligand concentration, the volume of water disperser, salt effect, and extraction time were optimized. The linear range, detection limit（S/N=3） and precision（RSD, n=6） were determined to be 0.2―50, 0.07 μg/L and 5.3%, respectively. The results reveal that the new approach is competitive analytical tool and an alternative of the traditional methods in the crude oil and related systems.

关键词： Nano-basket Dispersive liquid-liquid microextraction Vanadyl porphyrin Calixarene

Determination of Dioxins in Blood Using Nano-baskets Doped in Emulsion Liquid Membranes

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Chemical Research in Chinese Universities 2013年第1期29卷 30-36页

作者： MOKHTARI bahram POURABDOLLAH Kobra Razi Chemistry Research Center(RCRC) Shahreza Branch Islamic Azad University Shahreza Iran

Extraction of dioxins from blood samples was carried out by inclusion-facilitated emulsion liquid membrane process. The novelty of this work is the application of nano-baskets of calixarene and emulsion liquid membranes in the selective and efficient preconcentration of dioxin. For this aim, four derivatives ofp-tert-calix[4]arene bearing different sulfonamide moieties were synthesized and their inclusion-extraction parameters were optimized including the calixarene＇s scaffold and concentration（as the carrier/demulsifier）, the diluent type in membrane, the phase and the treat ratio, mixing speed, and initial solute concentration. Determinations were followed by a gas chromatograph and the results reveal that under the optimized operating conditions, the preconcentration of dioxins was improved and the method achieved lower limit of detections（LODs）. Under optimal conditions, the figures of merits were determined to be LOD 1.0 pg/L, dynamic range 0.6--112.0 pg/L, RSD 5.5%（n=5）, and the maximum enrichment factor and recovery were determined to be 3.3 and 99%, respectively.

关键词： Nano-basket Dioxin Inclusion Calixarene Emulsion liquid membrane

Power systems wide-area voltage stability assessment considering dissimilar load variations and credible contingencies

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 78-87页

作者： bahram SHAKERIGHADI Farrokh AMINIFAR Saeed AFSHARNIA School of Electrical and Computer Engineering College of Engineering University of Tehran

This paper reveals that the existing techniques have some deficiencies in the proper estimation of voltage stability margin(VSM) when applied to a power system with different load change *** problem gets worse when credible contingencies *** paper proposes a real-time wide-area approach to estimate VSM of power systems with different possible load change scenarios under normal and contingency operating *** new method is based on an artificial neural network(ANN) whose inputs are bus voltage phasors captured by phasor measurement units(PMUs) and rates of change of active power loads.A new input feature is also accommodated to overcome the inability of trained ANN in prediction of VSM under N-1 and N-2 *** a new algorithm, the number of contingencies is reduced for the effective training of *** of the proposed technique is assured through adding a random noise to input *** deal with systems with a limited number of PMUs, a search algorithm is accomplished to identify the optimal placement of *** proposed method is examined on the IEEE 6-bus and the New England 39-bus test *** show that the VSM could be predicted with less than 1% error.

关键词： Artificial neural network(ANN) Phasor measurement unit(PMU) Voltage stability margin(VSM)

Separation of Salbutamol by Nano-baskets of Calix[4]arene Bearing Sulfonyl-carboxamides in Partial-cone Conformation

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Chemical Research in Chinese Universities 2012年第6期28卷 1112-1118页

作者： MOKHTARI bahram POURABDOLLAH Kobra Razi Chemistry Research Center(RCRC) Shahreza BranchIslamic Azad University

Salbutamol,which increases the muscle mass and decreases the adipose tissue,is misused as nutrient repartitioning agent in the *** novelty of this work is the determination of salbutamol in the livestock meat via new bonded-phases bearing eight derivatives of p-tert-calix[4]arene in partial-cone *** new synthesized bonded-phases were characterized and *** bonding interactions of solute and stationary-phases were examined and the main interactions were *** salbutamol levels in six samples of livestock meat were analyzed and the results reveal that for the best bonded-phases,the limit of detection（LOD） and limit of quantitation（LOQ） were 0.02 and 0.06 μg/mL,respectively.

关键词： Nano-basket Bonded-phase Partial-cone conformation Calixarene Salbutamol

Influence of random heterogeneity of shear wave velocity on sliding mass response and seismic deformations of earth slopes

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 269-287页

作者： Pourya Kazemi Esfeh bahram Nadi Nicholas Fantuzzi Department of Civil ChemicalEnvironmentaland Materials EngineeringUniversity of BolognaItaly Department of Civil Engineering Azad University of NajafabadIran

Soil shear wave velocity has been recognized as a governing parameter in the assessment of the seismic response of *** spatial variability of soil shear wave velocity can influence the seismic response of sliding mass and seismic ***,most analyses of sliding mass response have been carried out by deterministic *** paper stochastically investigates the effect of random heterogeneity of shear wave velocity of soil on the dynamic response of sliding mass using the correlation matrix decomposition method and Monte Carlo simulation(MCS).The software FLAC 7.0 along with a Matlab code has been utilized for this *** influence of statistical parameters on the seismic response of sliding mass and seismic displacements in earth slopes with different inclinations and stiffnesses subject to various earthquake shakings was *** results indicated that,in general,the random heterogeneity of soil shear modulus can have a notable impact on the sliding mass response and that neglecting this phenomenon could lead to underestimation of sliding deformations.

关键词： random heterogeneity random fields Monte Carlo simulation sliding mass response seismic deformations

ANALYTICAL ANALYSIS OF MEMS CAPACITIVE PRESSURE SENSOR WITH CIRCULAR DIAPHRAGM UNDER DYNAMIC LOAD USING DIFFERENTIAL TRANSFORMATION METHOD(DTM)

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Acta Mechanica Solida Sinica 2015年第4期28卷 400-408页

作者： Marzieh Molla-Alipour bahram Azizollah Ganji Department of Engineering South Tehran Branch Islamic Azad University Department of Electrical Engineering Babol University of Technology

In this paper, first a circular diaphragm is modeled using the classical plate theory. An analytical solution based on differential transformation method （DTM） and Runge-Kutta method is employed for solving the governing differential equation for the first time. Then the influences of various parameters on central deflection of the diaphragm, stress distribution and capacitance of pressure sensor with a time-dependent pressure are examined. Several case studies are compared with simulations to confirm the proposed method. The analytical results compared with ABAQUS simulation show excellent agreement with the simulation results. This method is very promising for time saving in calculating micro-device characteristics.

关键词： MEMS capacitive pressure sensor circular diaphragm deflection analytical model,theoretical analysis

Estimation of froth flotation recovery and collision probability based on operational parameters using an artificial neural network

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 526-534页

作者： Saeed Chehreh Chelgani Behzad Shahbazi bahram Rezai Surface Science Western Research Park University of Western Ontario Mining Engineering Department Science and Research Branch Islamic Azad University Amirkabir University of Technology

An artificial neural network and regression procedures were used to predict the recovery and collision probability of quartz flotation concentrate in different operational conditions. Flotation parameters, such as dimensionless numbers （Froude, Reynolds, and Weber）, particle size, air flow rate, bubble diameter, and bubble rise velocity, were used as inputs to both methods. The linear regression method shows that the relationships between flotation parameters and the recovery and collision probability of flotation can achieve correlation coefficients （R2） of 0.54 and 0.87, respectively. A feed-forward artificial neural network with 3-3-3-2 arrangement is able to simultaneously estimate the recovery and collision probability as the outputs. In testing stages, the quite satisfactory correlation coefficient of 0.98 was achieved for both outputs. It shows that the proposed neural network models can be used to determine the most advantageous operational conditions for the expected recovery and collision probability in the froth flotation process.

关键词： flotation recovery collision probability neural networks

Hydrological alteration and biodiversity change along the river network caused by anthropogenic activities and climate variability

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Ecological Processes 2022年第1期11卷 189-205页

作者： Farshid Zolfagharpour bahram Saghafian Majid Delavar Department of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Water Resources Engineering Tarbiat Modares UniversityTehranIran

Background:Population growth and intensified human activities in conjunction with climate variability continue to affect the hydrologic cycle,aquatic and terrestrial flora and *** this regard,understanding interactions among ecosystem functions,impacts of anthropogenic interventions and those of climate variability is vital for projecting future ecosystem responses to human activities and climate *** objectives of this study are to determine the ecological flow state via eco-flow index based on discharge hydrograph,to model the ecological diversity through the Shannon diversity index,and to assess the degree of hydrologic alteration using indicators of hydrologic alteration and range of variability approach in six hydrometric stations along the Zayandeh-Rud River in central *** river drains into Gavkhuni ***,the streamflow-induced potential changes for Capoeta damascina(a cyprinid fish species of the genus Capoeta),Petroleuciscus esfahani(a small cyprinid fish)and Aphanius isfahanensis(a Cyprinodontid fish)are *** outcome is expected to assist managers with understanding the effects of anthropogenic activities and climate variability on Gavkhuni aquatic ecosystems so that management options that enhance species resilience and adaptability are ***:Human activities,a primary factor influencing the natural flow regime,caused a significant increase in the minimum flow,July to March streamflow,low pulse number,and the number of reversals in most studied *** the contrary,some other hydrologic indices declined in *** impoundment,the most prominent factor among human interventions,resulted in an overall alteration degree of 74.8%in *** variability impacted the natural flow regime in the range of low degree hydrologic alteration(27.3%).In addition,the biodiversity of the study basin,as modeled by the Shannon diversity index,had strong relevance to the annual eco-surplus and was more sensitive

关键词： Eco-flow Shannon diversity index Human activity Indicators of hydrologic alteration Natural flow regime Range of variability Zayandeh-Rud River