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Journal of Earth Science 2020年第3期31卷 596-610页

作者： mohammad Seraj Ali Faghih hossein Motamedi Bahman Soleimany Department of Earth Sciences、College of Sciences Shiraz UniversityShirazIran Exploration Directorate of the National Iranian Oil Company(NIOC) TehranIran Reaserch Institute of Petroleum Industry(RIPI) TehranIran

The Zagros fold-thrust belt(ZFTB)formed from the progressive collision between the African-Arabian and Eurasian *** study focuses on the major tectonic lineaments concerned with the distribution of oilfields in the southern Dezful Embayment as an extremely rich hydrocarbon province in the ZFTB,SW *** of surface,near-surface and sub-surface data(e.g.,remote sensing,overburden rocks,reservoir and aeromagnetic data)were used for locating major tectonic lineaments in the study *** results show that the southern Dezful Embayment area was influenced by tectonic lineaments oriented in the NW-SE,NE-SW,E-W and N-S trends,which are possible fault indicators corresponding to surface,shallow subsurface and basement *** dominant N-S and E-W tectonic lineaments possibly highlight the stress regime inherited from old structures in the Arabian Shield basement while the NE-SW,NW-SE trends are interpreted as effects of the Zagros ***,these tectonic lineaments influenced both the basement and sedimentary rocks and are used here to divide the belt into several faulted blocks with different structural frameworks.A clear picture of the tectonic trends influencing the Zagros fold-thrust belt oilfields as well as guidance for delineating hydrocarbon reservoirs in the future are presented.

关键词： aeromagnetic data remote sensing tectonic trend hydrocarbon Zagros Iran

Electrocatalytic oxidation of hydrazine with alizarin red S as a homogenous mediator on the glassy carbon electrode

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Science China Chemistry 2010年第5期53卷 1194-1200页

作者： mohammad Mazloum-Ardakani Roya Mazidi mohammad hossein Mashhadizadeh Parvanah Rahimi mohammad Ali Karimi Department of Chemistry Faculty of ScienceYazd University Department of Chemistry Payam Noor UniversityArdakan Center Department of Chemistry Faculty of ScienceTarbiat Moalem University Department of Chemistry Faculty of SciencePayam Noor UniversitySirjan Center

Electro-catalytic oxidation and detection of hydrazine on a glassy carbon electrode,at pH 6.0,was studied by using alizarin red S as a homogeneous *** overall number of electrons involved in the catalytic oxidation of hydrazine and that involved in the rate-determining step were four and one,*** interfering effect of some cations,anions and organic compounds were *** current for this process varied linearly with the square root of the scan *** kinetic parameters,such as the electron transfer coefficient(α) and catalytic rate constant(k) ,were determined using cyclic voltammetry,linear sweep voltammetry and *** electro-catalytic response was optimized with regards to the pH,scan rate,hydrazine concentration and other variables.

关键词： alizarin red S hydrazine glassy carbon electrode electro-catalytic oxidation voltammetry

Hydrodynamic mechanisms of aggressive collapse events in leading edge cavitation

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Journal of Hydrodynamics 2020年第1期32卷 6-19页

作者： mohammad hossein Arabnejad Ali Amini Mohamed Farhat Rickard EBensow Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden Laboratory for Hydraulic Machines EPFLLausanneSwitzerland

Transient cavities generated from unsteady leading-edge cavitation may undergo aggressive collapses which are responsible for cavitation *** this paper,we studied the hydrodynamic mechanisms of these events in the leading edge cavitation fonned over a modified NACA0009 hydrofoil using experimental and numerical *** the experimental investigation,high-speed visualization(HSV)and paint test are employed to study the behavior of the cavitating flow at σ=1.25,α=5°,U∞=20 m/*** the numerical part,the same cavitating flow is simulated using an inviscid density-based compressible solver with a barotropic cavitation *** numerical results are first compared with the experimental HSV to show that the simulation is able to reproduce the main features of the cavitating ***,as the compressible solver is capable of capturing the shock wave upon the collapse of cavities,the location of collapse events with high erosion potential are *** location of these collapse events are compared with the paint test results with a qualitatively good *** is clearly observed,in both the experiments and the numerical simulation,that there exists four distinct regions along the hydrofoil with higher risks of erosion:(1)A very narrow strip at the leading edge,(2)an area of accumulated collapses at around 60 percent of the sheet cavity maximum length,(3)an area around the closure line of the sheet cavity with the highest erosion damage,and(4)a wide area close to the trailing edge with dispersed collapse events.A combined analysis of the experimental and numerical results reveals that the small-scale structures generated by secondary shedding are more aggressive than the large-scale cloud cavities(primary shedding).It is also observed that the high risk of cavitation erosion in regions 2 and 3 is mainly due to the collapses of the small cavity structures that are formed around the sheet cavity closure line or the rolling cloud cavity.

关键词： Hydrodynamic mechanisms aggressive collapse events high-speed visualization(HSV) paint test compressible simulation of cavitating flows

Impacts of vegetation over bedforms on flow characteristics in gravel-bed rivers

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Journal of Hydrodynamics 2019年第5期31卷 986-998页

作者： hossein Afzalimehr mohammad Reza Maddahi Jueyi Sui Majid Rahimpour Department of Civil Engineering Iran University of Science and TechnologyTehranIran Department of Water Engineering Shahid Bahonar University of KermanKermanIran Environmental Engineering Program University of Northern British ColumbiaCanada

In the present study,among six gravel-bed river reaches,two natural gravel-bed river reaches with approximately similar bedforms and flow conditions have been found,one river reach with vegetation on bedforms and the other without vegetation on *** on field measurements,the impacts of vegetation over bedforms on flow characteristics have been *** velocity,Reynolds stress and turbulence intensity distributions over bedforms with vegetation have been compared with those over gravel bedforms without *** using the quadrant analysis,the dominant events of turbulent flow structures have been assessed for flows over gravel bedforms with vegetation and without *** show that the effect of vegetation enhances the anisotropy in turbulence and generates strong secondary currents,which lead to the occurrence of dip phenomenon at the stoss section and the crest of vegetated *** change of bed roughness from gravel bed to vegetated bed causes a development of a new boundary *** resulted in the different shape of velocity distributions over bedforms with vegetation from those over bedforms without vegetation,which can affect the lives of aquatic *** shear stress at downstream section of gravel bedform without vegetation is much higher than that of vegetated bedform,which shows that the erosion takes place from downstream of vegetated bedforms,while in the bare beds;the deposition is at downstream of *** is found that the presence of vegetation causes a chaotic distribution pattern of Reynolds shear stress,while it has more orderly pattern at the downstream section of gravel bedform without ***,the distribution of turbulence intensity in the lee side of vegetated bedform has a concave shape and in the stoss section,turbulence is generated in ejections and sweeps near the vegetation *** findings are significant to the practice of river ecological restoration.

关键词： Bedform Reynolds shear stress distribution turbulence intensity vegetation velocity profiles

Phase Stability in Mechanically Alloyed Mg–Ni System Studied by Experiments and Thermodynamic Calculations

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1002-1007页

作者： mohammad hossein Enayati Fathallah Karimzadeh Soheil Sabooni Majid Jafari Department of Materials Engineering Isfahan University of Technology

In this study, microstructural evolution of Mg–Ni alloy during mechanical alloying（MA） was ***, a thermodynamic approach was utilized to predict the most stable phases formed in Mg–Ni alloy after MA. The phase composition and microstructural properties of Mg–Ni alloy were assessed by X-ray diffractometry, high-resolution field emission scanning electron microscopy and high-resolution transmission electron microscopy. The results showed that ball milling of magnesium and nickel powder mixture for 70 h yields nanostructural Mg2Ni compound with an average grain size of ~20 nm. Thermodynamic calculations revealed that in the composition ranges of 0.0 ／ XMg／ 0.03（at.%）and 0.97 ／ XMg／ 1, there is no driving force for amorphous phase formation. In the composition range of 0.07 ／ XMg／ 0.93, the change of Gibbs free energy for amorphous phase formation was more negative than solid *** for XMg= 0.66（nominal composition of Mg2Ni intermetallic phase）, the change of Gibbs free energy for intermetallic phase was found to be more negative than both amorphous and solid solution phases indicating that Mg2Ni intermetallic compound is the most stable phase, in agreement with the experimental observations.

关键词： Mechanical alloying Nanocrystalline Hydrogen storage material Mg2Ni Thermodynamics

Green bio-synthesis of Ni/montmorillonite nanocomposite using extract of Allium jesdianum as the nano-catalyst for electrocatalytic oxidation of methanol

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2555-2565页

作者： mohammad hossein Sheikh-Mohseni Sajjad Sedaghat Pirouz Derakhshi Aliakbar Safekordi Department of Chemistry Science and Research BranchIslamic Azad UniversityTehranIran Department of Chemistry Shahr-e-Qods BranchIslamic Azad UniversityShahr-e-QodsIran Department of Chemistry North Tehran BranchIslamic Azad UniversityTehranIran

In this work,synthesis of Ni nanoparticles was carried out successfully by water extract of Allium jesdianum as a biochemical reducing agent in the presence of montmorillonite clay(MMT)as a natural solid support for the first *** the electrochemical activity of the synthesized nanocomposite was investigated in methanol electrocatalytic *** with high cation exchange capacity and nano layer structure was exposed to ion exchange conditions in nickel *** Ni^2+ion exchanged form was used in this process as a source of ions and also capping *** extract of Allium jesdianum used as a reducing agent due to abundant availability of phenolic and flavonoid *** synthesized Ni/MMT nanocomposite was characterized using UV–Vis spectroscopy(UV–Vis),Fourier Transform Infrared Spectroscopy(FT-IR),X-ray diffraction(XRD),Scanning Electron Microscopy(SEM),Transmission electron microscopy(TEM)and Energy-dispersive X-ray spectroscopy(EDX).The surface of prepared modified electrode has been characterized using SEM to evaluate the morphology,showing uniform dispersion of Ni nanoparticles with mean diameter of 12 to 20 *** modified carbon paste electrode was then used in methanol electrocatalytic oxidation *** oxidation on the proposed modified electrode surface occurs at 0.6 V and 0.3 V in alkaline and acidic medium ***,the results showed the better performance of modified electrode toward methanol electrocatalytic oxidation in comparison with carbon paste electrode that is modified by ion exchanged *** transfer coefficients and apparent charge transfer rate constant for the modified electrode in the absence of methanol in alkaline medium were respectively found as:αa=0.53,αc=0.37 and ks=1.6×10^-1 s^-***,the average value of catalytic rate constant for the electrocatalytic oxidation of methanol by the prepared nano-catalyst was estimated to be about 0.9 L·mol^-1·s^-1 by chronoamperometry *** prepare

关键词： Green biosynthesis Nanoparticles Montmorillonite Biocatalysis Methanol electrocatalytic oxidation Fuel cell

Histological and biochemical alterations in early-stage lobar ischemia-reperfusion in rat liver

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World Journal of Gastroenterology 2009年第16期15卷 1951-1957页

作者： hossein Ali Arab Farhang Sasani mohammad hossein Rafiee Ahmad Fatemi Abbas Javaheri Department of Pharmacology Faculty of Veterinary MedicineUniversity of Tehran Department of Pathology Faculty of Veterinary MedicineUniversity of Tehran Faculty of Veterinary Medicine University of Semnan

AIM： To investigate the structural and biochemical changes in the early stage of reperfusion in the rat livers exposed to lobar ischemia-reperfusion （IR）. METHODS： The median and left lobes of the liver were subjected to 60 min ischemia followed by 5, 10, 30, 45, 60 and 120 min reperfusion. Blood samples were taken at different time intervals to test enzyme activities and biochemical alterations induced by reperfusion. At the end of each reperfusion period, the animals were killed by euthanasia and tissue samples were taken for histological examination and immunohistochemistry. RESULTS： Cell vacuolation, bleb formation and focal hepatitis were the most important changes occur during ischemia. While some changes including bleb formation were removed during reperfusion, other alterations including portal hepatitis, inflammation and the induction of apoptosis were seen during this stage. The occurrence of apoptosis, as demonstrated by apoptotic cells and bodies, was the most important histological change during reperfusion. The severity of apoptosis was dependent on the time of reperfusion, and by increasing the time of reperfusion, the numbers of apoptotic bodies was significantly enhanced. The amounts of lactate dehydrogenase, alanine aminotransferase, aspartate aminotransfrase, creatinine and urea were significantly increased in serum obtained from animals exposed to hepatic IR. CONCLUSION： Inflammation and subsequent apoptotic cell death were the most important changes in early-stage hepatic reperfusion injury, and the number of apoptotic bodies increased with time of reperfusion.

关键词： Lobar ischemia Liver Reperfusion injury Apoptosis Immunohistochemistry

Mg-P/c-SWCNT Bone Cement: The Effect of Filler on Setting Behavior,Compressive Strength and Biocompatibility

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Journal of Bionic Engineering 2020年第1期17卷 100-112页

作者： mohammad hossein Esnaashary Alireza Khavandi Hamid Reza Rezaie Jafar Javadpour School of Metallurgical and Materials Engineering Iran University of Science and TechnologyNarmakTehran 16844Iran

Improving the strength of bone cement is one of the critical goals in cement designing to maintain their integrity and stabilize connection between the cement and their surrounding tissue during the time that the cement has been replaced by matured bone *** this aim,the authors decided to evaluate setting behavior and compressive strength of Magnesium Phosphate Cement(MPC)by adding carboxylated Single-Walled Carbon Nanotubes(c-SWCNTs)and assess the biocompatibility of the composite *** containing 0 wt%to 0.5 wt% of c-SWCNTs at the Powder to Liquid Ratio(PLR)of 1 g·mL^-1 to 2 g·mL^-1 were *** c-SWCNTs to MPC postponed the setting time of the cement at the beginning of the cementation process and preserved the reaction with a high rate for a longer *** addition,the compressive strength of MPC was enhanced to 28 MPa by adding 0.2 wt%c-SWCNTs because of producing cement with compact and uniform *** addition,cell behavior on MPC with/without c-SWCNTs indicated no cytotoxic effect alongside a suitable adhesion and proliferation of them.

关键词： magnesium phosphate cement carbon nanotube compressive strength MTT bone cement biocompatibility

Computational analysis of neutronic effects of ThO_2 rods loaded in CANDU 6 fuel assemblies

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Nuclear Science and Techniques 2016年第4期27卷 14-20页

作者： Seyed mohammad Mirvakili Zohreh Gholamzadeh Seyed Amir hossein Feghhi Reactor Research School Nuclear Science and Technology Research Institute Department of Radiation Application Shahid Beheshti UniversityG.C

Thorium as a suitable fertile with higher natural resources in comparison with uranium resources has been remarkably considered by different nuclear energy user countries in the last decades. Its prominent features such as suitable possibility for power flattening of a nuclear reactor, applicable breeder blanket to produce^(233)U fissile as well as neutron leakage prevention from a nuclear core has caused its application as power flatter, breeder material or other aimed utilizations be evaluated by the researches. In the present study, neutronics of a modeled CANDU 6loaded with Th O_2 and UO_2fuel rods have been computationally studied. The study aimed at reprocessing of burned Th O_2 seeds at CANDU 6 reactor to recover the total produced uranium, which is to be going under another compound fuel cycle. The obtained results showed all the core reactivity coefficients are sufficiently negative. The modeled core 949 GWd burn-up concluding in 99.99 %depletion of^(235)U initial loads. 18.38 kg of^(233) U was produced in the burnt Th O_2 fuel after 1-year burn-up time. In addition, 31.84 kg of^(239) Pu was produced in the UO_2 spent fuel rods after the burn-up time. After a proposed cooling time, about 50.01 kg of^(233)U will be available in the spent Th O_2 fuel.

关键词： CANDU堆中子泄漏燃料组件稳定杆计算核反应堆燃烧时间自然资源

A Wide-Neighborhood Predictor-Corrector Interior-Point Algorithm for Linear Complementarity Problems

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Journal of the Operations Research Society of China 2018年第4期6卷 529-543页

作者： mohammad Pirhaji hossein Mansouri Maryam Zangiabadi Department of Applied Mathematics Faculty of Mathematical SciencesShahrekord UniversityShahrekordIran

In this paper,a wide-neighborhood predictor-corrector feasible interiorpoint algorithm for linear complementarity problems is *** algorithm is based on using the classical affine scaling direction as a part in a corrector step,not in a predictor *** convergence analysis of the algorithm is shown,and it is proved that the algorithm has the polynomial complexity O(√n logε^(−1))which coincides with the best known iteration bound for this class of mathematical *** numerical results indicate the efficiency of the algorithm.

关键词： Linear complementarity problems Predictor-corrector algorithm Polynomial complexity