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Chinese Chemical Letters 2012年第8期23卷 883-886页

作者： Hassan Zare Mohammad Mehdi Ghanbari marzieh jamali Abdollah Aboodi Department of Chemistry Firoozabad BranchIslamic Azad UniversityFiroozabadIran Department of Chemistry Sarvestan BranchIslamic Azad UniversitySarvestanIran

We present an efficient, fast and simple strategy of generating the intermediate carbamoyl chlorides from secondary amines using stoichiometric amounts of bis（trichloromethyl）carbonate （BTC） in solution and solvent-free conditions with excellent yields. The results obtained showed the yield increasing on whether a base was used. Finally, an efficient and rapid synthesis of variety carbamate derivatives was developed by the reaction with a high variety of different alcohols, phenols, diols and this intermediate at room temperature with grinding and in solvent-free conditions under microwave irradiation. The presence of various safe bases is shown to be effective in reducing the reaction times, increasing the yields and easing purification. The present method does not involve any hazardous phosgene.

关键词： Bis(trichloromethyl)carbonate Carbamoyl chloride Carbamate Microwave irradiation Solvent-free Grinding

Prevalence of retinal pathologies in people over 60 years:the Tehran Geriatrics Eye Study

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 721-728页

作者： Abolghasem Mortazavi Alireza Hashemi Alirerza jamali Hassan Hashemi Mohammadreza Aghamirsalim Mehdi Khabazkhoob Department of Neurosurgery Sina HospitalTehran University of Medical SciencesTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Translational Ophthalmology Research Center Tehran University of Medical SciencesTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To determine the prevalence of some retinal pathologies in people over 60y and their association with demographic and ocular ***:A cross-sectional study was conducted in Tehran using multistage cluster *** selecting subjects aged 60 and over,optometric,and ophthalmic examinations were *** retinal examination,a 90 D lens was used and indirect ophthalmoscopy was performed after instilling tropicamide *** was done using the IOL Master for all ***:Of 3791 people that were invited through cluster sampling,3310 participated in the study(response rate=82%).The prevalence of retinal pigmented epithelium(RPE)change,drusen,geographic atrophy(GA),hypertensive retinopathy(HTR),nonproliferative diabetic retinopathy(NPDR),proliferative diabetic retinopathy(PDR),choroidal neovascularization(CNV),central retinal artery occlusion(CRAO),myopic retinopathy(MR),branch retinal vein occlusion(BRVO),and central retinal vein occlusion(CRVO)was 27.42%,11.08%,4.52%,3.03%,4.05%,0.54%,0.82%,0.39%,0.20%,0.49%,and 0.19%,*** removing the effect of age,the odds of NPDR were 1.68 times higher in women compared to men(P=0.014).After removing the effect of sex,the odds of drusen,RPE change,GA,CNV,BRVO,and CRVO increased with ***:There is a higher prevalence of RPE change,drusen,GA,CNV and a lower prevalence of MR and CRAO in the elderly population of Tehran aged over 60y compared to global average *** the correlation of most of the diseases with age and their effects on vision,attention should be paid to these diseases and the related screening programs to prevent vision impairment.

关键词： retinal pathologies cross-sectional study vision impairment

基于多方位采集激光诱导击穿光谱的高温合金判别分析方法

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分析试验室 2024年

作者：张梦阳付洪波王华东杨彦红 Saifullah jamali 张志荣中国科学技术大学研究生院科学岛分院中国科学院合肥物质科学研究院安徽光学精密机械研究所光子器件与材料安徽省重点实验室中国科学院金属研究所师昌绪先进材料创新中心中国科学院合肥物质科学研究院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室国防科技大学先进激光技术安徽省实验室

高温合金是指以铁、镍、钴为基体，能在600 ℃以上高温及一定应力作用下长期工作的一类金属材料，在航空航天和能源领域具有重要应用价值，高温合金的在线原位判别对质量控制、生产监管、回收利用等具有重要意义。本研究采用多方位采集... 详细信息

高温合金是指以铁、镍、钴为基体，能在600 ℃以上高温及一定应力作用下长期工作的一类金属材料，在航空航天和能源领域具有重要应用价值，高温合金的在线原位判别对质量控制、生产监管、回收利用等具有重要意义。本研究采用多方位采集优化的激光诱导击穿光谱（LIBS）技术结合机器学习算法，对GH625，GF718，GH738，GH907，GH4141，GH4378，GH5188等7类共72块高温合金样品进行快速分类。每个样品随机选择5个分析位置，每个分析位置通过多方位采集装置获取200幅光谱。运用异常值剔除、滤波降噪和标准正态变量变换（SNV）对LIBS光谱数据进行预处理，并选取经主成分分析（PCA）降维后的前5个主成分，作为线性判别分析（LDA）、K近邻（KNN）和支持向量机（SVM）等分类模型的输入。结果表明，PCA-SVM模型的分类性能最优，其训练集准确度达到了100%，测试集数据分类准确度为99.048%。LIBS技术与PCA-SVM方法相结合是一种很有前途的对不同牌号高温合金样品进行分类和鉴定的方法。

关键词：激光诱导击穿光谱高温合金机器学习判别分析

硅胶键合的N-丙基三亚乙基四胺氨基磺酸作为可回收固体酸催化剂催化合成2-氨基-4,6-二芳基烟腈(英文)

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催化学报 2012年第8期33卷 1312-1317页

作者： Khodabakhsh NIKNAM Abbas jamali marzieh TAJADDOD Abdollah DERIS Department of Chemistry Faculty of SciencesPersian Gulf UniversityBushehr 75169Iran

A simple and efficient procedure for the preparation of silica-bound N-propyl triethylenetetramine sulfamic acid(SBPTETSA) by the reaction of silica-bound N-propyl triethylenetetramine(SBPTET) with chlorosulfonic acid in chloroform is ***-bound N-propyl triethylenetetramine sulfamic acid was employed as a recyclable catalyst for the synthesis of 2-amino-4,6-diarylnicotinonitriles from the multi-component reaction of an acetophenone derivative,an aromatic aldehyde,malononitrile,and ammonium acetate under solvent-free conditions at 100 °*** heterogeneous catalyst was recycled for five consecutive runs in the optimized multi-component reaction of 4-chloroacetophenone,4-chloroenzaldehyde,malononitrile,and ammonium acetate without significant loses to its catalytic activity.

关键词：三乙烯四胺固体酸催化剂氨基磺酸氧化硅可回收丙基合成苯乙酮衍生物

Optimal selection of annulus radius ratio to enhance heat transfer with minimum entropy generation in developing laminar forced convection of water-Al2O3 nanofluid flow

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Journal of Central South University 2017年第8期24卷 1850-1865页

作者： Siavashi Majid jamali Mohammad Applied Multi-Phase Fluid Dynamics Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran

Heat transfer and entropy generation of developing laminar forced convection flow of water-Al_2O_3 nanofluid in a concentric annulus with constant heat flux on the walls is investigated numerically. In order to determine entropy generation of fully developed flow, two approaches are employed and it is shown that only one of these methods can provide appropriate results for flow inside annuli. The effects of concentration of nanoparticles, Reynolds number and thermal boundaries on heat transfer enhancement and entropy generation of developing laminar flow inside annuli with different radius ratios and same cross sectional areas are studied. The results show that radius ratio is a very important decision parameter of an annular heat exchanger such that in each Re, there is an optimum radius ratio to maximize Nu and minimize entropy generation. Moreover, the effect of nanoparticles concentration on heat transfer enhancement and minimizing entropy generation is stronger at higher Reynolds.

关键词： nanofluid heat transfer enhancement forced convection entropy generation annulus radius ratio

A wavelet packet based method for adaptive single-pole auto-reclosing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 1016-1024页

作者： Sadegh jamali Navid GHAFFARZADEH Centre of Excellence in Power Systems Automation and Operation Iran University of Science and Technology Tehran Iran

We present a new algorithm for adaptive single-pole auto-reclosing of power transmission lines using wavelet packet transform. The db8 wavelet packet decomposes the faulted phase voltage waveform to obtain the coefficients of the nodes 257, 259 to 262. An index is then defined from the sum of the energy coefficients of these nodes. By evaluating the index, transient and permanent faults, as well as the secondary arc extinction instant, can be identified. The significant advantage of the proposed algorithm is that it does not need a threshold level and therefore its performance is independent of fault location, line parameters, and operating conditions. Moreover, it can be used in transmission lines with reactor compensation. The proposed method has been successfully tested under a variety of fault conditions on a 400 kV overhead line of the Iranian National Grid using the Electro-Magnetic Transient Program (EMTP). The test results validated the algorithm’s ability in distinguishing between transient arcing and permanent faults and determining the instant of secondary arc extinction.

关键词： Adaptive auto-reclosing Arcing faults Permanent faults Transmission lines Wavelet packet transform

Microstructure and mechanical properties of AA6063 aluminum alloy wire fabricated by friction stir back extrusion(FSBE) process

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International Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 1005-1012页

作者： Ghasem jamali Salman Nourouzi Roohollah Jamaati Department of Materials Engineering Babol Noshirvani University of Technology

In the present work,the friction stir back extrusion(FSBE)process was used as a novel method for the fabrication of AA6063 aluminum alloy *** electron microscopy(SEM)equipped with energy dispersive spectroscopy(EDS),tensile and hardness tests were *** FSBE via the rotational speed of 475 r/min resulted in fine equiaxed grains,and the mean grain size decreased from 179.0μm to 15.5μm due to the occurrence of dynamic recrystallization(DRX).Heat generated by the FSBE changed the size and volume fraction of the Mg2Si precipitated *** minimum particle size and maximum volume fraction obtained in the sample were processed by rotational speeds of 475 and 600 r/min,*** 475-r/min sample had the maximum hardness value due to having the lowest grain size(i.e.,15.5μm)and the presence of many fine Mg2Si precipitates in the aluminum *** increasing rotational speed up to 600 r/min,the hardness decreased,owing to the growth of both grains and *** FSBE process with a rotational speed of 475 r/min increased the tensile strength(from 150 to 209 MPa)and ductility(from 21.0%to 30.2%)simultaneously.

关键词： aluminum alloys friction stir back extrusion microstructure mechanical properties

Experimental evaluation and modeling of liquid jet penetration to estimate droplet size in a three-phase riser reactor

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Chinese Journal of Chemical Engineering 2016年第2期24卷 293-309页

作者： Ali Akbar jamali Shahrokh Shahhosseini Yaghoub Behjat School of Chemical Engineering Iran University of Science and Technology (IUST) Process Development and Equipment Technology Division Research Institute of Petroleum Industry

In this work, the effects of injecting an evaporating liquid jet into solid-gas flow are experimentally investigated. A new model （SHED model） and a supplementary model （spray model） have also been proposed to investigate some flow-field characteristics in three-phase fluidized bed with the mean relative error 4.3% between model and measured results. Some experiments were conducted to study the influences of flow-field parameters such as liquid volumetric flow rate, injection velocity, jet angle and gas superficial velocity as well as solid mass flux on the jet penetration depth （JPD）. In addition, independent variables were experimentally employed to propose two empirical correlations for JPD by using multiple regression method and spray cone angle （SCA） by using dimensional analysis technique. The mean relative errors between the JPD and SCA correlations versus ex- perimental data were 7.5% and 3.9%, respectively. In addition, in order to identify the variable effect, a parametric study was carried out. Applying the proposed model can avoid direct use of expensive devices to measureJPD and to nredict dronlet size.

关键词： FC-C riser reactor Hydrod ynamics Heterogeneous vaporization Jet penetration depth (JPD) Spray cone angle (SCA)

Hybrid classifier for fault location in active distribution networks

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Protection and Control of Modern Power Systems 2020年第1期5卷 194-202页

作者： Sadegh jamali Alireza Bahmanyar Siavash Ranjbar Centre of Excellence for Power System Automation and Operation School of Electrical EngineeringIran University of Science and TechnologyP.O.Box:16846-13114TehranIran

This paper presents a fast hybrid fault location method for active distribution networks with distributed generation(DG)and *** method uses the voltage and current data from the measurement points at the main substation,and the connection points of DG and *** data is used in a single feedforward artificial neural network(ANN)to estimate the distances to fault from all the measuring points.A k-nearest neighbors(KNN)classifier then interprets the ANN outputs and estimates a single fault *** results validate the accuracy of the fault location method under different fault conditions including fault types,fault points,and fault *** performance is also validated for non-synchronized measurements and measurement errors.

关键词： Artificial neural networks Distributed generation Distribution networks Fault location K-nearest neighbors

Survivability evaluation for networks carrying complex traffic flows

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Digital Communications and Networks 2023年第2期9卷 534-544页

作者： Amin jamali Mehdi Berenjkoub Hossein Saidi Behrouz Shahgholi Ghahfarokhi Faculty of Computer Engineering University of IsfahanIsfahan***Iran Department of Electrical and Computer Engineering Isfahan University of TechnologyIsfahan***Iran

The capability of a system to fulfill its mission promptly in the presence of attacks,failures,or accidents is one of the qualitative definitions of *** this paper,we propose a model for survivability quantification,which is acceptable for networks carrying complex traffic *** network traffic is considered as general multi-rate,heterogeneous traffic,where the individual bandwidth demands may aggregate in complex,nonlinear *** probability is the chosen measure for survivability *** study an arbitrary topology and some other known topologies for the *** and dependent failure scenarios as well as deterministic and random traffic models are ***,we provide survivability evaluation results for different network *** results show that by using about 50%of the link capacity in networks with a relatively high number of links,the blocking probability remains near zero in the case of a limited number of failures.

关键词： Blocking probability Complex traffic Link failure Network survivability Disaster recovery Information assurance