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Optimizing the Synthesis of Ethyl tert-Butyl Ether in Continuous Catalytic Distillation Column Using New Ion Exchange Resin Catalyst

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Chinese Journal of Chemical Engineering 2013年第10期21卷 1121-1128页

作者： Muhammad Umar yahia Abubakar AI-Hamed Abdulraheem AI-Zahrani Hisham Saeed Bamufleh Department of Chemical and Materials Engineering Faculty of Engineering King Abdul Aziz University Jeddah80204 Kingdom of Saudi Arabia

Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether （ETBE）, from etha-nol and tert-butyl alcohol （TBA） has been studied in catalytic distillation column （CDC） using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found：reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.

关键词： ethyl tert-butyl ether synthesis catalytic distillation ion exchange resin catalyst packed column mul-tiplicity

阿尔及利亚-欧盟联合协定对阿尔及利亚对外贸易的影响研究

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阿尔及利亚-欧盟联合协定对阿尔及利亚对外贸易的影响研究

作者： BABAAMER DJELMAM yahia 江西财经大学

学位级别：硕士

本文试图考察阿尔及利亚-欧洲联盟协会协议对阿尔及利亚对外贸易的影响。与欧洲联盟的伙伴关系协议是该组织呼吁欧洲联盟的巴塞罗那项目的一部分,该项目旨在发展与欧亚国家之间的合作关系。地中海南部,创造一个共同的长期繁荣区。该研... 详细信息

本文试图考察阿尔及利亚-欧洲联盟协会协议对阿尔及利亚对外贸易的影响。与欧洲联盟的伙伴关系协议是该组织呼吁欧洲联盟的巴塞罗那项目的一部分,该项目旨在发展与欧亚国家之间的合作关系。地中海南部,创造一个共同的长期繁荣区。该研究的重点是阿尔及利亚与欧盟之间的伙伴关系问题,因为它对扩大国际合作空间以实现可持续发展具有重大影响,因此被认为是重要的研究领域和专家课题之一。增加实现世界和平从而实现世界稳定的机会。该研究旨在试图解决欧洲伙伴关系的问题,其成因是什么,实现其对阿尔及利亚的经济和社会影响,其带来的好处发展和不利,以及如何从经验和知识转让中受益。技术,以及在过去十年中达到的另一种。在其中,我们讨论了自由贸易区及其法律地位,除了使海关制度适应《伙伴关系协定》,海关拆除对公共财政平衡和贸易平衡的影响之外,还讨论了目标,优势和劣势以及阿尔及利亚和欧洲联盟之间的伙伴关系对阿尔及利亚经济特别是对外贸易的影响通过这项研究,我们得出结论,欧洲联盟正在寻求与地中海国家建立伙伴关系,以扩大其全球影响力并巩固其市场地位,但是既定目标使地中海地区成为该伙伴关系的福利领域之一,研究还发现,阿尔及利亚和欧盟之间的伙伴关系不是战略选择,而是对世界经济转型和阿尔及利亚采用的贸易方式的一种反应。

关键词：阿尔及利亚-欧洲联盟协会自由贸易区一体化影响

Determination of the Activation Energy for Migration the Dislocation in 7075 Aircraft Material by Positron Annihilation Lifetime and Electrical Techniques

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材料科学与工程（中英文A版） 2011年第5X期1卷 711-716页

作者： Nasser Abdel-Azeem Kamel yahia A. Lotfy Physics Department Faculty of Science EI-Minia University Egypt

Positron annihilation lifetime (PAL) is one of the most important nuclear techniques used in material science. Electrical measurements are also used in material science. Samples of 25% deformation have been used for these studies. Both positron annihilation lifetime and electrical measurements were used to determine the activation energy of migration the dislocation in 7075 alloy. The isothermal annealing measurements were performed at 643, 663, 683 and 703 K. The activation energy of migration the dislocation is obtained as 1.35 ± 0.16 eV and 1.25 ± 0.05 eV for positron annihilation lifetime and electrical techniques, respectively.

关键词：正电子湮没寿命电气技术活化能飞机材料错位移民测定电气测量

The Arab Turmoil:An Exploratory Interpretation

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The Arab Turmoil:An Exploratory Interpretation

Medical influences,surgical outcomes: Role of common medications on the risk of perforation from untreated diverticular disease

北京论坛（2011）文明的和谐与共同繁荣--传统与现代、变革与转型

作者： yahia H.Zoubir International Relations & International Management

Introduction The uprisings in the Arab world are a remarkable phenomenon. Whatever the end-result might be, the reality in most countries of the region will never be the same. The Arab regimes have managed to escape the third wave of democratization in the world of which Eastern Europe was the best example. Arab regimes, including Egypt, Algeria, and Tunisia, have managed to create an"electoral authoritarianism 1 ";a democratic appearance that was nothing but a new form

关键词： The Arab Turmoil:An Exploratory Interpretation

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World Journal of Gastroenterology 2013年第36期19卷 5947-5952页

作者： Gianpiero Gravante Shuker yahia Department of Colorectal SurgeryGeorge Eliot Hospital

Numerous drugs,largely used in the wards or at home,have a significant influence on patients with untreated diverticular *** consequences can be disastrous,may require an emergency operation,postoperative intensive care,and overall influence the patient’s length of stay and the final *** these considerations in mind the routine or chronic administration of pain-killers,steroids and non-steroidal anti-inflammatory should be balanced in patients with known diverticular disease as it normally happens with other conditions potentially affected by these drugs(i.e.,peptic ulcer disease or chronic obstructive pulmonary disease).This is even more important in the old and frail patient where an eventual surgical treatment may not always be possible.

关键词： Perforation Diverticular disease Medications Drugs Risk factor

角膜胶原蛋白交联术在圆锥角膜及其他眼部疾病中的应用

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角膜胶原蛋白交联术在圆锥角膜及其他眼部疾病中的应用

作者： Adel yahia alhayek 苏州大学

学位级别：硕士

圆锥角膜是由于角膜的生物力学不稳定,角膜中央变薄向前突出,呈圆锥形改变为特征的一种眼病,表现为持续进展的不规则的散光,不伴有炎症。角膜胶原蛋白交联术是一种联合运用感光剂核黄素和紫外线照射来加强角膜组织硬度,增加胶原纤维的... 详细信息

圆锥角膜是由于角膜的生物力学不稳定,角膜中央变薄向前突出,呈圆锥形改变为特征的一种眼病,表现为持续进展的不规则的散光,不伴有炎症。角膜胶原蛋白交联术是一种联合运用感光剂核黄素和紫外线照射来加强角膜组织硬度,增加胶原纤维的机械强度达到抵抗角膜扩张的一种新技术。既往的研究表明,在运用角膜胶原蛋白交联术后四年内,能够有效地阻止圆锥角膜的进一步发展。此外,研究还发现角膜胶原蛋白交联术至少能够降低2D的屈光度,等效球镜度数下降1D。目前,角膜胶原蛋白交联术主要运用于角膜变形类疾病以及预防过度激光消融所导致的医源性的角膜扩张。此外,这种治疗也被用于治疗感染性的角膜溃疡。但是角膜胶原蛋白交联术也存在一些长期和短期并发症。由于需要清除患者角膜上皮以及接触镜头,会造成继续感染,形成角膜斑翳、疤痕、内皮损伤、治疗失败、大疱性及疱疹病毒性角膜病等并发症。作为一种微创手术,角膜胶原蛋白交联术通过加强基质胶原蛋白的强度来稳定潜在的角膜扩张,延缓或者避免角膜移植。本综述的目的主要是明确角膜胶原蛋白交联术在治疗角膜扩张类疾病中的有效性和安全性。

关键词：圆锥角膜角膜胶原蛋白角膜病变

Statistical Studies of the Physicochemical Analytic Results of a Series of Synthetic Calcium Hydroxyapatite Containing Carbonate and Sodium

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American Journal of Analytical Chemistry 2014年第5期5卷 343-357页

作者： Faouzia Rockh B. Hadj yahia Ismail Khattech Faculty of Science Chemistry Department Applied Thermodynamics Laboratory Tunis El Manar Tunisia

The objective of this study is to present a simple method of statistical calculation that allowed us to determine the relationship between the different data obtained from the characterization of the synthetic carbonated apatites containing sodium, in order to find the fundamental substitution mechanism(s) for incorporation of Na+ and?CO32- and to establish the general formula. For that, a series of hydroxyapatites containing carbonate and sodium (Na-CO3HAps) has been obtained by the precipitation method. All the compounds were characterized by infrared spectra (IR), powder X-ray diffraction (PXRD) and elemental analysis. The statistical treatment of the experiment result allows us to determine the relationship between one variable and the change in the other and to found the fundamental substitution mechanism(s) for incorporation of Na+ and?CO32- . Analysis of variance (ANOVA) allows us to test the models proposed.

关键词： Carbonated Calcium Hydroxyapatite Containing Sodium Na-CO3HAps Statistical Studies Multiple Linear Regression Analysis of Variance (ANOVA)

New Decision-Making Technique Based on Hurwicz Criteria for Fuzzy Ranking

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Computers, Materials & Continua 2022年第12期73卷 4595-4609页

作者： Deepak Sukheja Javaid Ahmad Shah G.Madhu K.Sandeep Kautish Fahad A.Alghamdi Ibrahim.S.yahia El-Sayed M.El-Kenawy Ali Wagdy Mohamed Department of Computer Science and Engineering VNR Vignana Jyothi Institute of Engineering and TechnologyHyderabadIndia Department of Mathematics Dr.APJ Abdul Kalam University Indore(M.P)India Department of Information Technology VNR Vignana Jyothi Institute of Engineering and TechnologyHyderabadIndia LBEF Campus Kathmandu44600Nepal Department of Management Information Systems College of Applied Studies and Community ServiceImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Laboratory of Nano-Smart Materials for Science and Technology(LNSMST) Department of PhysicsFaculty of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Nanoscience Laboratory for Environmental and Biomedical Applications(NLEBA) Semiconductor Lab.Department of PhysicsFaculty of EducationAin Shams UniversityRoxyCairo 11757Egypt Department of Communications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Operations Research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Department of Mathematics and Actuarial Science School of Sciences Engineering The American University in CairoEgypt

Efficient decision-making remains an open challenge in the research community,and many researchers are working to improve accuracy through the use of various computational *** this case,the fuzzification and defuzzification processes can be very *** is an effective process to get a single number from the output of a fuzzy *** defuzzification as a center point of this research paper,to analyze and understand the effect of different types of vehicles according to their *** this paper,the multi-criteria decision-making(MCDM)process under uncertainty and defuzzification is discussed by using the center of the area(COA)or ***,to find the best solution,Hurwicz criteria are used on the defuzzified ***-making technique is proposed using Hurwicz criteria for triangular and trapezoidal fuzzy *** proposed technique considers all types of decision makers’perspectives such as optimistic,neutral,and pessimistic which is crucial in solving decisionmaking problems.A simple case study is used to demonstrate and discuss the Centroid Method and Hurwicz Criteria for measuring risk attitudes among *** significance of the proposed defuzzification method is demonstrated by comparing it to previous defuzzification procedures with its application.

关键词： Defuzzification decision-making fuzzy numbers Hurwicz multicriteria decision-making ranking order

Determination of the Optical Properties of Basal Cancer Using OCT System

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Open Journal of Biophysics 2019年第2期9卷 88-97页

作者： Sohad Elwakeel Nafie Almuslet yahia Badr Aldeen Khalid Haroun Institute of Laser Sudan University of Science and Technology Khartoum Sudan National Institute of Laser Enhanced Science Cairo University Cairo Egypt Facility of Radiobiological and Imagine Science Alzaaim Alazahari University Khartoum Sudan

The objective of this work is to determinate the optical properties of basal cancer cells using an optical coherence tomography (OCT). OCT system with He-Ne & diode laser was used to make interference pattern for the basal cancer, then the output was displayed by optical detector, information of an electrical signal passed to the digital oscilloscope to give the object information after Fourier transform processing for that signal, then PC and CCD were used to display FFT signal. Finally many steps were done to determine the optical properties for the basal cancer. The intensity of the signals was plotted against scanning distance;the obtained graphs were used to determine the penetration depth and absorption coefficient.

关键词： Optical Imaging Resolution FT Cancer Cell Optical Properties