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Nonlinear beam formulation incorporating surface energy and size effect:application in nano-bridges

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Applied Mathematics and Mechanics(English Edition) 2016年第5期37卷 583-600页

作者： A.KOOCHI H.hosseini-TOUDESHKY M.ABADYAN Department of Aerospace Engineering Amirkabir University of TechnologyTehran 15875-4413Iran Mechanical Engineering Group Shahrekord BranchIslamic Azad UniversityShahrekord ***Iran

A nonlinear beam formulation is presented based on the Gurtin-Murdoch surface elasticity and the modified couple stress theory. The developed model theoretically takes into account coupled effects of the energy of surface layer and microstructures size- dependency. The mid-plane stretching of a beam is incorporated using von-Karman nonlinear strains. Hamilton＇s principle is used to determine the nonlinear governing equation of motion and the corresponding boundary conditions. As a case study, pull-in instability of an electromechanical nano-bridge structure is studied using the proposed formulation. The nonlinear governing equation is solved by the analytical reduced order method （ROM） as well as the numerical solution. Effects of various parameters including surface layer, size dependency, dispersion forces, and structural damping on the pull- in parameters of the nano-bridges are discussed. Comparison of the results with the literature reveals capability of the present model in demonstrating the impact of nano- scale phenomena on the pull-in threshold of the nano-bridges.

关键词： surface energy size effect nonlinear beam formulation electromechanicalnano-bridge pull-in instability

Corrosion Protection of Electro-Galvanized Steel by Green Conversion Coatings

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Journal of Rare Earths 2007年第5期25卷 537-543页

作者： Mirghasem hosseini Habib Ashassi-Sorkhabi Heshmat Allah Yaghobkhani Ghiasvand Electrochemistry Research Laboratory Physical Chemistry Department Chemistry Faculty University of Tabriz

A A cerium-based chemical conversion process was studied. First, zinc coating obtained from a free-cyanide alkaline bath, with derivative of imidazol with new brightener, was investigated, zinc-plated steel specimens were treated with a solution of 50 mmol· L^-1 Ce（NO3 ）3 The corrosion behavior of bare and treated mild galvanized steel was evaluated during exposure to 0.5 mol · L^-1 NaCl for different immersion time, using Tafel polarization curves and electrochemical impedance spectroscopy （EIS） measurements. The surface morphology of the coating was studied using scanning electron microscopy （SEM）. The composition and chemical percent of the coating were examined by X-ray dispersion energy （EDAX）. The results of these measurements showed that the newly developed cerium-based conversion coating process was a promising candidate for replacing the conventional chromate treatments used at present for galvanized steel.

关键词： green coating free-cyanide alkaline bath EIS electro-galvanized rare earths

Application of CFD technique to simulate enhanced oil recovery processes:current status and future opportunities

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Petroleum Science 2020年第2期17卷 434-456页

作者： Arezou Jafari Mohammadreza Hasani Mostafa hosseini Reza Gharibshahi Faculty of Chemical Engineering Tarbiat Modares UniversityTehranIran

Nowadays,because of the reduction in oil resources and the passage of the first and second life period of current reservoirs,using enhanced oil recovery(EOR)methods is of great *** recent years,due to the developments in technology and the advent of powerful computers,using simulation methods in enhanced oil recovery processes is on the *** computational fluid dynamics(CFD)method,as a branch of fluid mechanics,is a suitable method for studying and simulating EOR *** this study,a review was done on the application of CFD studies for simulating EOR ***,potentials for future studies and the challenges researchers may face in this method were *** using this method in enhanced oil recovery processes has recently started,different areas for more studies still *** optimize the usage of this method in future studies,the necessity of multiphase models and solution methods development,as well as considering all microscopic parameters such as interfacial tension and viscosity in investigating oil recovery factor is of great importance.

关键词： Enhanced oil recovery Computational fluid dynamics Oil recovery factor Thermal methods Chemical methods Flooding methods

Protective efficacy of dark chocolate in letrozole-induced ovary toxicity model rats: hormonal, biochemical, and histopathological investigation

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Journal of Traditional Chinese Medicine 2022年第5期42卷 741-748页

作者： Naser Mirazi Sheida Hesami Alireza Nourian Abdolkarim hosseini Department of Biology Faculty of Basic SciencesBu-Ali Sina UniversityHamedan ***Iran Department of Pathobiology Faculty of Veterinary ScienceBu-Ali Sina UniversityHamedan ***Iran Department of Animal Sciences and Biotechnology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran

OBJECTIVE: To assess the protective effect of dark chocolate(DC) on the letrozole-induced rat model of polycystic ovary syndrome(PCOS). METHODS: In this experimental study, 32 female Wistar rats, weighing(200 ± 20) g, were randomly categorized into 4 groups including control, letrozole(1 mg·kg-1·d-1), metformin(500 mg·kg-1·d-1) along with letrozole, and DC(500 mg·kg-1·d-1) along with letrozole for 28 d by oral gavage. Twenty-four hours after the last supplementation, direct blood sampling was taken from the heart to obtain blood serum for evaluation of sex hormones and gonadotropins, oxidative parameters, inflammatory cytokines, and ovarian tissue was examined for histology. RESULTS: The DC treatment significantly improved PCOS signs, as demonstrated by the significant restoration of ovarian morphology and physiological functions as compared with the letrozole group. DC treatment also decreased ovarian interleukin-1β and tumor necrosis factor-α levels and improved total oxidative/antioxidative status as compared with the letrozole group. CONCLUSIONS: Treating the animals with DC could alleviate the PCOS symptoms and reduced the toxic effects of letrozole in the ovary. This effect may mediate through antioxidant and antiinflammatory properties.

关键词： chocolate letrozole metformin polycystic ovary syndrome antioxidants anti-inflammatory agents

Numerical study of aerosol particle deposition in simple and converging-diverging micro-channels with a slip boundary condition at the wall

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Particuology 2014年第2期12卷 100-105页

作者： Seyed Mohammad Javad hosseini Ataallah Soltani Goharrizi Bahador Abolpour Department of Chemical Engineering Faculty of EngineeringShahid Bahonar University of Kerman

The design of micro-devices involving aerosol transport requires the study of the deposition of aerosols in micro-channels. In this study, the slip and no-slip boundary conditions for the gas flow regime were applied to the Navier-Stokes equations to obtain the particle deposition in simple and converging-diverging micro-channels. The equation of particle motion included inertial, viscous, Brownian, and gravity terms. It was found that the ratio of gravity to inertial effects controls the deposition of particles with diameters of 0.1-1 μm, and the ratio of diffusion to inertial effects controls the deposition of particles with diameters of 0.01-0.001 i^m. Comparison between the no-slip and slip flow regimes showed that the deposition of 0.1- to 1-μm-diameter particles was less and the deposition of 0.01- to 0.001-1μm-diameter particles was greater for the slip flow regime. There was no significant difference between slip and no-slip flow regimes for the deposition of 0.01- to 0.1-μm-diameter particles. Finally, it was shown that the stagnated gas in the corners of the converging-diverging micro-channel produced similar gas velocity profiles under the slip and no-slip flow regimes.

关键词： Aerosol depositionMicro-channelConverging-diverging micro-channelSlip boundary condition

URANS simulations for a free-running container ship:Part 2. Added power

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Journal of Hydrodynamics 2021年第3期33卷 448-467页

作者： Dong-Hwan Kim Yugo Sanada Hamid Sadat-hosseini Frederick Stern IIHR-Hydroscience and Engineering The University of IowaIowa CityUSA Costal Development and Ocean Energy Research Center Korea Institute of Ocean Science and TechnologyBusanKorea Mechanical Engineering University of North TexasDentonUSA

Part 2 reports the validation,local force and local flow study results for the free-running added power simulations whose conditions are the same as the self-propulsion test except for the increased propeller rotational speed and the presence of *** targeting the same mean Froude number in the wave condition,the propeller requires the increased propeller rotational speed for the operation at the low advance ratio due to the added *** test is performed at five different wavelengths in head waves and four different headings in the oblique *** the validation study,the time series of the validation variables is decomposed with discrete Fourier transform to extract the harmonic *** variables are global parameters,including motions,propeller thrust,and torque coefficients,added power variables,and self-propulsion factors which show reasonable agreement against the experiment results and produces a similar error from the self-propulsion *** local force study shows that the added resistance mostly appears at the bow due to the bow plunging during the short head wave and resonance *** contributions of the gravitational force and the buoyant force are found to increase as the stern motion exceeds the bow motion during the long head wave *** oscillation of the propeller performances shows correlation with the first harmonic amplitude of the propeller ***,pitch,and roll decay tests are performed prior to the main test to assess the natural frequencies of the *** as Part 1,a discretized propeller is used.

关键词： Added power unsteady Reynolds-averaged Navier-Stokes(URANS) KRISO Container Ship(KCS) CFDShip-IOWA

Impacts of COVID-19 Pandemic on Italian Electricity Demand and Markets

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 824-827页

作者： Mahmood hosseini Imani Ettore Bompard Pietro Colella Tao Huang Politecnico di Torino Dipartimento EnergiaTurin10129Italy

In this paper,the short-,medium-,and long-term effects of the COVID-19 pandemic on the Italian power system,particularly electricity consumption behavior and electricity market prices,are investigated by defining various *** investigation reveals that COVID-19 lockdown caused a drop in load consumption and,consequently,a decrement in day-ahead market prices and an increase in ancillary service prices.

关键词： Ancillary service market price COVID-19 day-ahead market price Italian electricity markets load consumption

Matching user identities across social networks with limited profile data

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Frontiers of Computer Science 2020年第6期14卷 171-184页

作者： Ildar NURGALIEV Qiang QU Seyed Mojtaba hosseini BAMAKAN Muhammad MUZAMMAL Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Sberbank Moscow 121170Russia Department of Management Yazd UniversityYazd 89195-741Iran Department of Computer Science Bahria UniversityIslamabad 44000Pakistan

Privacy preservation is a primary concern in social networks which employ a variety of privacy preservations mechanisms to preserve and protect sensitive user information including age,location,education,interests,and *** task of matching user identities across different social networks is considered a challenging *** this work,we propose an algorithm to reveal user identities as a set of linked accounts from different social networks using limited user profile data,i.e,user-name and ***,we propose a framework,ExpandUIL,that includes three standalone al-gorithms based on(i)the percolation graph matching in Ex-pand FullName algorithm,(i)a supervised machine learning algorithm that works with the graph embedding,and(ii)a combination of the two,ExpandUserLinkage *** proposed framework as a set of algorithms is significant as,(i)it is based on the network topology and requires only name feature of the nodes,(i)it requires a considerably low initial seed,as low as one initial seed suffices,(ii)it is iterative and scalable with applicability to online incoming stream graphs,and(iv)it has an experimental proof of stability over a real ground-truth *** on real datasets,Instagram and VK social networks,show upto 75%recall for linked ac-counts with 96%accuracy using only one given seed pair.

关键词： social networks user identity linkage graph structure learning,maximum subgraph matching graph percolation

Solvent-free Knoevenagel Condensations over TiO2

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Chinese Journal of Chemistry 2007年第10期25卷 1563-1567页

作者： hosseini-SARVARI, Mona SHARGHI, Hashem ETEMAD, Samane Department of Chemistry Faculty of Science Shiraz University Shiraz 71454 Iran

A study involving the scope of substrates in the Knoevenagel reaction under SFC has been conducted. Reactivity trends favored formation of the condensation product using both electron deficient and rich aryl aldehydes. A recycling study confirmed that the reaction medium could be used multiple times affording, with each run, the desired condensation product in excess of 95% conversion.

关键词： titanium dioxide aldehyde malononitrile Knoevenagel condensation solvent-free