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EIS Study on Pitting Corrosion of AA5083-h321 Aluminum-Magnesium Alloy in Stagnant 3.5% NaCl Solution

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Journal of Materials Science & Technology 2008年第2期24卷 215-219页

作者： K.Jafarzadeh T.Shahrabi M.G.hosseini Corrosion Lab. Materials Eng.Dept.Tarbiat Modares Univ.TehranIran Dept.of Physical Chemistry Facul-ty of ChemistryTabriz Univ.TabrizIran

In this research, EIS （electrochemical impedance spectroscopy） technique was utilized to study the pitting corrosion behaviour of AA5083-h321 aluminum-magnesium alloy in 3.5% NaCl solution. Impedance spectra were obtained during 240 h of exposure of the sample to the test solution. The surface and cross-section of the samples were studied by scanning electron microscopy （SEM） and EDAX （energy dispersive analysis of X-ray） analysis. The results indicated that as the resistance of the passive layer on intermetallic particles is very small, this parameter on the sample surface layers is controlled by that of pure passive layer. however, the capacitors in the proposed equivalent circuit are replaced with the constant phase elements （CPE）, due to non-uniformity and occurrence of pitting corrosion on the surface. The outward diffusion of Al^＋3 ions through the passive layer and the thickening of this layer cause the impedance decrease in the first 24 h and increase afterwards. The detachment of intermetallic particles from some of pits and the accumulation of the corrosion products inside some others are factors that prevents the continuation of cathodic reactions on the top of the intermetallic particles.

关键词： Corrosion AA5083-h321 aluminum-magnesium alloy Impedance Pitting Intermetallic particle Passive layer

基于多阶人工神经网络的ECG信号诊断模型研究

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仪器仪表学报 2008年第1期29卷 27-32页

作者：骆德汉许广桂邹宇华 h.Gholam hosseini 广东工业大学中国广州510006 奥克兰工业大学工程学院新西兰奥克兰1142

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的... 详细信息

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的ECG信号辅助诊断系统。首先给出多个不同结构的神经网络,然后针对6种不同的心脏状况,比较这些神经网络之间的性能差异和辨别能力。网络的输入数据来自于M IT/B Ih数据库,包括12种ECG特征信号和相应的每次心脏搏动的13段压缩信号。通过研究测试发现,基于二阶神经网络的ECG模型识别率最高,正确率达到了90.57%。

关键词： ECG信号分类器人工神经网络(ANN) ECG信号诊断多阶前馈神经网络

PTCAP工艺生产的Al 5083薄壁管吸能能力的实验验证和数值计算

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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1238-1248页

作者： A.hosseini D.RAhMATABADI R.hAShEMI h.AKBARI School of Mechanical Engineering Iran University of Science and TechnologyTehranIran

对平行管角挤压(PTCAP)工艺生产的Al5083薄壁管的吸能能力进行评价。研究沿周向和轴向方向的显微结构、力学性能和各向异性系数。结果表明:能量吸收值随加工道次的增加而降低,未处理、第一道次和第二道次处理的样品的能量吸收值分别为16... 详细信息

对平行管角挤压(PTCAP)工艺生产的Al5083薄壁管的吸能能力进行评价。研究沿周向和轴向方向的显微结构、力学性能和各向异性系数。结果表明:能量吸收值随加工道次的增加而降低,未处理、第一道次和第二道次处理的样品的能量吸收值分别为167、161.4和160.7J。能量吸收值的数值模拟结果与未处理的、第一和第二道次PTCAP处理后样品之间的误差分别约为5%、10%和13%。吸能能力与各向异性系数和显微结构有关。结果表明,经过一道次和二道次PTCAP处理后,晶粒得到细化,极限抗拉强度和显微硬度均得到提高,但一道次处理后的提高幅度更大。此外,通过PTCAP处理,变形模式发生改变,退火后样品的变形模式非常对称且呈圆形,而第一和第二道次变形样品的变形模式为三叶和双叶钻石形状。退火管和PTCAP处理管变形模式的数值模拟结果与实验结果一致。总之,薄壁管的变形模式取决于其力学性能和PTCAP过程中力学性能的变化。

关键词：吸能 Al 5083 超细晶铝合金薄壁管大塑性变形各向异性系数

A new multilevel voltage source inverter configuration with minimum number of circuit elements

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Journal of Central South University 2017年第4期24卷 912-920页

作者： Mohammad Reza Jannati Oskuee Masoumeh Karimi Yahya Naderi Sajad Najafi Ravadanegh Seyyed hossein hosseini Smart Distribution Grid Research Lab. Electrical Engineering Department Azarbaijan Shahid Madani University Tabriz Iran Faculty of Electrical and Computer Engineering University of Tabriz Tabriz Iran

An advanced configuration for multilevel voltage source converters is proposed. The proposed converter is able to apply asymmetrical DC sources. The configuration of the proposed inverter is well designed in order to provide the maximum number of voltage levels in output terminals using lower number of circuit devices. The authority of the proposed inverter versus the conventional h-bridge cascaded inverter and the most recently introduced ones, is verified with a provided comparison study. The proposed inverter is able to generate the desired voltage levels using a lower number of circuit devices including power semi-conductor switches, IGBTs, diodes, related gate driver circuits of switches and DC voltage sources. As a result, the total cost and installation area are considerably reduced and the control scheme gets simpler. To confirm the feasibility of the proposed multilevel structure, both the simulation and experimental results are provided and compared which shows good agreements.

关键词： multilevel voltage source inverter reduction of circuit components symmetric inverter asymmetric inverter

Structure-activity relationship of pyrazol-4-ylpyridine derivatives and identification of a radiofluorinated probe for imaging the muscarinic acetylcholine receptor M4

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Acta Pharmaceutica Sinica B 2023年第1期13卷 213-226页

作者： Ahmed haider Xiaoyun Deng Olivia Mastromihalis Stefanie K.Pfister Troels E.Jeppesen Zhiwei Xiao Vi Pham Shaofa Sun Jian Rong Chunyu Zhao Jiahui Chen Yinlong Li Theresa R.Connors April T.Davenport James B.Daunais Vahid hosseini Wenqing Ran Arthur Christopoulos Lu Wang Celine Valant Steven h.Liang Department of Radiology Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical SchoolBostonMA 02114USA Department of Nuclear Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Drug Discovery Biology Monash Institute of Pharmaceutical SciencesMonash UniversityParkvilleVIC 3052Australia Neuromedicines Discovery Centre Monash Institute of Pharmaceutical SciencesMonash UniversityParkvilleVIC 3052Australia hubei Collaborative Innovation Centre for Non-power Nuclear Technology College of Nuclear Technology&Chemistry and BiologyHubei University of Science and TechnologyXianning 437100China Department of Neurology Massachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA Department of Physiology and Pharmacology Wake Forest School of MedicineWinston SalemNC 27157USA Terasaki Institute for Biomedical Innovation(TIBI) Los AngelesCA 90024USA Center of Cyclotron and PET Radiopharmaceuticals Department of Nuclear Medicine and PET/CT-MRI Centerthe First Affiliated Hospital of Jinan UniversityGuangzhou 510630China

There is an accumulating body of evidence implicating the muscarinic acetylcholine receptor4(M4)in schizophrenia and dementia with Lewy bodies,however,a clinically validated M4positron emission tomography(PET)radioligand is currently *** such,the aim of this study was to develop a suitable M4PET ligand that allows the non-invasive visualization of M4in the ***-activity relationship studies of pyrazol-4-yl-pyridine derivates led to the discovery of target compound 12—a subtype-selective positive allosteric modulator(PAM).The radiofluorinated analogue,[18F]12,was synthesized in 28±10%radiochemical yield,>37 GBq/μmol and an excellent radiochemical purity>99%.Initial in vitro autoradiograms on rodent brain sections were performed in the absence of carbachol and showed moderate specificity as well as a low selectivity of[18F]12 for the M4-rich ***,in the presence of carbachol,a significant increase in tracer binding was observed in the rat striatum,which was reduced by>60%under blocking conditions,thus indicating that orthosteric ligand interaction is required for efficient binding o f[18F]12 to the allosteric ***,however,the presence of carbachol was not required for high specific binding in the non-human primate(NhP)and human striatum,and did not further improve the specificity and selectivity of[18F]12 in higher *** results pointed towards significant species-differences and paved the way for a preliminary PET study in NhP,where peak brain uptake of[18F]12 was found in the putamen and temporal *** conclusion,we report on the identification and preclinical development of the first radiofluorinated M4PET radioligand with promising *** availability of a clinically validated M4PET radioligand harbors potential to facilitate drug development and provide a useful diagnostic tool for non-invasive imaging.

关键词： Muscarinicacetylcholine receptor Positronemission tomography Neuroimaging Neuropharmacology Neurological disorders

Role of Chloride Ion and Dissolved Oxygen in Electrochemical Corrosion of AA5083-h321 Aluminum-Magnesium Alloy in NaCl Solutions under Flow Conditions

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Journal of Materials Science & Technology 2007年第5期23卷 623-628页

作者： K.Jafarzadeh T.Shahrabi S.M.M.hadavi M.G.hosseini Department of Materials Engineering.Tarbiat Modares University TehranIran Faculty of Material Engineering Malek Ashtar UniversityTehranIran Electrochemistry Research Lab. Chemistry FacultyTabriz UniversityTabrizDan

Flow-induced corrosion consists electrochemical and mechanical components. The present paper has to assessed the role of chloride ion and dissolved oxygen in the electrochemical component of flow induced corrosion for AA5083-h321 aluminum-magnesium alloy which is extensively used in the construction of high-speed boats, submarines, hovercrafts, and desalination systems, in NaCI solutions. Electrochemical tests were carried out at flow velocities of 0, ：2, 5, 7 and 10 m/s, in aerated and deaerated NaCI solutions with different sodium chloride concentrations. The results showed that the high rate of oxygen reduction under hydrodynamic conditions causes an increase in the density of pits on the surface. The increase of chloride ions concentration under flow conditions accelerates the rate of anodic reactions, but have no influence on the cathodic reactions. Thus, in the current work, it was found that under flow conditions, due to the elimination of corrosion products inside the pits, corrosion resistance of the alloy is increased.

关键词： Corrosion Flow NaCl solution AA5083-h321 aluminum-magnesium alloy Chloride ion Oxygen

On the evaluation of steam assisted gravity drainage in naturally fractured oil reservoirs

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Petroleum 2017年第2期3卷 273-279页

作者： Seyed Morteza Tohidi hosseini Shayan Esfahani Mehran hashemi Doulatabadi Abdolhossein hemmati Sarapardeh Amir h.Mohammadi Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Institut de Recherche en Genie Chimique et Petrolier(IRGCP) Paris CedexFrance Thermodynamics Research Unit School of EngineeringUniversity of KwaZulu-NatalHoward College CampusKing George V AvenueDurban 4041South Africa Departement de Genie des Mines de la Metallurgie et des MateriauxFaculte des Sciences et de GenieUniversite LavalQuebec(QC)G1V 0A6Canada

Steam Assisted Gravity Drainage(SAGD)as a successful enhanced oil recovery(EOR)process has been applied to extract heavy and extra heavy *** amount of global heavy oil resources exists in carbonate reservoirs which are mostly naturally fractured *** clastic reservoirs,few studies were carried out to determine the performance of SAGD in carbonate *** though SAGD is a highly promising technique,several uncertainties and unanswered questions still exist and they should be clarified for expansion of SAGD methods to world wide applications especially in naturally fractured *** this communication,the effects of some operational and reservoir parameters on SAGD processes were investigated in a naturally fractured reservoir with oil wet rock using CMG-STARS thermal *** purpose of this study was to investigate the role of fracture properties including fracture orientation,fracture spacing and fracture permeability on the SAGD performance in naturally fractured ***,one operational parameter was also studied;one new well configuration,staggered well pair was *** indicated that fracture orientation influences steam expansion and oil production from the horizontal well *** was also found that horizontal fractures have unfavorable effects on oil production,while vertical fractures increase the production rate for the horizontal ***,an increase in fracture spacing results in more oil production,because in higher fracture spacing model,steam will have more time to diffuse into matrices and heat up the entire ***,an increase in fracture permeability results in process enhancement and ultimate recovery ***,diagonal change in the location of injection wells(staggered model)increases the recovery efficiency in long-term production plan.

关键词： SAGD EOR Naturally fractured reservoir Operational parameters

An ionic 2D inorganic-organic hybrid of tris[((1h-tetrazol-5-yl)methyl)morpholine] dodecatungstophosphate(Ⅴ) pentahydrate:Synthesis X-ray crystal structure and spectroscopic characterizations

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Chinese Chemical Letters 2010年第4期21卷 501-505页

作者： Mohsen Nikpour hossein Eshtiagh.hosseini Masoud Mirzaei Amir Aghaei Kaju Soroush Zarinabadi Department of Chemistry School of SciencesIslamic Azad UniversityAhvaz BranchAhvaz 61349-68875Iran Department of Chemistry School of SciencesFerdowsi University of MashhadMashhadP.O.Box 917791436Iran Department of Chemistry Khorassan Science & Technology ParkMashhadP.O.Box 91735139Iran

A unique ionic hybrid material[C_6h_(12)N_5O]_3[(PO_4)W__(12)O_(36)]·5h_2O has been synthesized from the reaction of((1h-tetrazole-5- yl)methyl)morpholine andα-h_3[(PO_4)W_(12)O_(36)]·21h_*** has successfully been characterized by elemental analysis,IR and ~1h NMR spectroscopies,TGA and single-crystal X-ray diffraction *** title compound is constructed from the three [C_6h_(12)N_5O]^+ cations andα-Keggin[(PO_4)W_(12)O_(36)]^(3-) *** most remarkable structural feature of this hybrid can...

关键词： Polyoxometalate Inorganic-organic hybrid Morpholine Dodecatungstophosphate Crystal structure

非对称N-(亚水杨基)二亚乙基三胺铜(Ⅱ)配合物的合成、结构分析和催化活性评价(英文)

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催化学报 2013年第7期34卷 1456-1461页

作者： hassan hosseini-MONFARED Sohaila ALAVI Milosz SICZEK Department of Chemistry University of Zanjan Faculty of Chemistry University of Wroclaw

A new copper(Ⅱ) complex of a non‐symmetric Schiff base, [CuII(saldien)(h2O)]+(1), has been synthesized and characterized by elemental analysis and several other spectroscopic methods (hsaldien = N‐(salicylidene)diethylenetriamine). The crystal structure of 1 has also been determined by X‐ray crystallography. The geometry of the complex cation in 1 was found to be distorted square pyramidal with the mononegative Schiff base coordinating to the copper in a tetradentate mode via the O,N,N', and N''‐donor atoms. The remaining coordination site was occupied by the O atom of a h2O molecule in the axial position. The catalytic potential of 1 was tested in the oxidation reactions of cyclooctene and cyclohexene with aqueous 30% h2O2/NahCO3 in acetonitrile. These reactions proceeded smoothly to give the corresponding epoxides with selectivity levels greater than 99%. This catalytic system also showed high levels of activity and selectivity towards the oxidation of cyclohexane (i.e., cyclohexanol 37% and cyclohexanone 54%) in comparison with most of the other Cu‐based systems reported in the literature.

关键词：三胺配合物催化活性亚水杨基非对称结构分析合成 Schiff碱亚乙基