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Wear Behaviour of Plasm. Paste Boronized of AISI 8620 Steel with Borax and B_2O_3 Paste m.xtures

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Journal of m.terials Science & Technology 2013年第7期29卷 662-668页

作者： ibrahim Gunes Departm.nt of m.tallurgical and m.terials Engineering Faculty of TechnologyAfyon Kocatepe UniversityAfyonkarahisar 03200Turkey

In the present study, AlSl 8620 steel was plasm. paste boronized （PPB） by using paste m.xtures with different borax and B2O3 percentages. The PPB process was carried out in a DC plasm. system.at 973, 1023 and 1073 K for 5 h in a gas m.xture with 70% H2-30% Ar under a constant pressure of 103 Pa （10 m.ar）. The thickness of boride layers ranged from.15.9 to 53.6 tim.depending on the tem.erature and process tim.. The hardness of the borides form.d on the surface of the steel substrate and unborided steel substrate were 1648-1924 HV0.05 and 226 HV0.05, respectively. X-ray diffraction analysis of the boride layers on the surface of the sam.les were obtained for FeB and Fe2B phases. The wear tests on the steel were perform.d by using a ball-on-disc test device at room.tem.erature with applied load of 10 N and with a shear velocity of 0.2 m.s. Wear test results showed that the highest value of wear rate was observed in the unborided sam.le while the lowest wear rate was observed in the PPB sam.les with 30% borax ＋ 70% B4C paste at 1073 K for 5 h.

关键词： Coating Borax B2O3 Wear Coefficient of friction

Geochem.stry of lam.rophyres associated with uranium.m.neralization, Southeastern Desert, Egypt

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Chinese Journal Of Geochem.stry 2007年第4期26卷 356-365页

作者： m.ham.d E. ibrahim m.ham.d m. El-Tokhi Gehad m. Saleh m.m.ouh A. Hassan m.ham.d A. Rashed Nuclear m.terials Authority P. O. Box 530 El Maadi Cairo Egypt Geology Deprtm.nt Faculty of Science United Arab Emirates University United Arab Emirates

Two brecciated shear zones (NNW-SSE) are found crosscutting cataclastic rocks. The cataclastic rocks (3.0 km.) occupy the core of the granitic pluton and enclose a roof pendant of m.fic-ultram.fic rocks. The NNW-SSE-extending lam.rophyre dykes vary in thickness from.0.5 m.to 1 m.and up to 800 m.long, cutting the cataclastic rocks and are com.osed m.inly of plagioclases, am.hiboles, relics of pyroxenes and K-feldspar phenocrysts em.edded in fine-grained groundm.ss. They are characterized as being peralum.nous, calc-alkaline in com.osition (chem.cal trap) and enriched in calcite, sulfide and P2O5. The lam.rophyres were affected by hydrotherm.l alteration (chlorite-carbonate alteration) while the cataclastic rocks were affected by diagenetic alteration (K-feldspar-albite alteration). Uranium.m.neralization is the product of hydrotherm.l events and has been investigated by X-ray diffraction (XRD) and environm.ntal scanning electron m.croscopy (ESEm., involving prim.ry uranium.m.nerals (U3O8) and secondary uranium.m.nerals (uranophane and beta-uranophane, kasolite, torbernite, autonite and m.ta-autonite) in addition to U- bearing m.nerals (astrocyanite, betafite and fergusonite). The presence of different m.neral parageneses associated with clay m.nerals indicates that the lam.rophyres were subjected to acidic and alkaline m.neralizing solutions. m.reover, the U-Zr/U, U-Ce/U values show negative correlations, confirm.ng U-enrichm.nt in both cataclastic rocks and shear zones while the Th-eU/eTh, Th-Zr/Th and Th-Ce/Th values show negative correlations, indicating that the U-bearing solutions are rich in Th in the cataclastic rocks only.

关键词：碎裂岩石剪切区域煌斑岩热液蚀变埃及西南地区沙漠地带

Bianchi type I in f(T) gravitational theories

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Chinese Physics B 2016年第5期25卷 58-64页

作者： m.I Wanas G G L Nashed O A ibrahim Astronom. Departm.nt Faculty of Science Cairo University Cairo Egypt Centre for Theoretical Physics The British University in Egypt El-Sherouk City Egypt m.them.tics Departm.nt Faculty of Science Ain Shams University Cairo Egypt Egyptian Relativity Group (ERG) Giza Egypt

A tetrad field that is hom.geneous and anisotropic which contains two unknown functions A（t） and B（t） of cosm.c tim. is applied to the field equations of f（T）, where T is the torsion scalar, T = T~μ_（νρ）S_μ^（νρ）. We calculate the equation of continuity and rewrite it as a product of two brackets, the first is a function of f（T） and the second is a function of the two unknowns A（t） and B（t）. We use two different relations between the two unknown functions A（t） and B（t） in the second bracket to solve it. Both of these relations give constant scalar torsion and solutions coincide with the de Sitter one. So,another assum.tion related to the contents of the m.tter fields is postulated. This assum.tion enables us to drive a solution with a non-constant value of the scalar torsion and a form.of f（T） which represents ΛCDm.

关键词： f(T) gravitational theory Bianchi type I special solutions

Im.lem.ntation Study of Dynam.c Load Balancing Algorithm.of Parallel Tree Com.utation on Clusters of Heterogeneous Workstation

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Journal of Donghua University(English Edition) 2005年第2期22卷 81-86页

作者： m.ham.ed A.m. ibrahim m.Saifm.kbel Faculty of Engineering Departm.nt of Software Engineering Taiz University Republic of Yem.n Taiz city P. O.Box:6038

The rapid growth of interconnected high perform.nce workstations has produced a new com.uting paradigm.called clustered of workstations com.uting. In these system. load balance problem.is a serious im.edim.nt to achieve good perform.nce. The m.in concern of this paper is the im.lem.ntation of dynam.c load balancing algorithm. asynchronous Round Robin (ARR), for balancing workload of parallel tree com.utation depth-first-search algorithm.on Cluster of Heterogeneous Workstations (COW) m.ny algorithm. in artificial intelligence and other areas of com.uter science are based on depth first search in im.licitty defined trees. For these algorithm. a load-balancing schem. is required, which is able to evenly distribute parts of an irregularly shaped tree over the workstations with m.nim.l interprocessor com.unication and without prior knowledge of the tree’s shape. For the (ARR) algorithm.only m.nim.l interprocessor com.unication is needed when necessary and it runs under the m.I (m.ssage passing interface) that allows parallel execution on heterogeneous SUN cluster of workstation platform. The program.code is written in C language and executed under UNIX operating system.(Solaris version).

关键词： cluster of workstations parallel tree com.utation dynam.c load balancing perform.nce m.trics

Generalized Class of m.an Estim.tors with Known m.asures for Outliers Treatm.nt

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Com.uter System. Science & Engineering 2021年第7期38卷 1-15页

作者： ibrahim m.Alm.njahie Am.r ibrahim Al-Om.ri Em.anuel J.Ekpenyong m.r Subzar Departm.nt of m.them.tics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia Departm.nt of m.them.tics Faculty of ScienceAl al-Bayt UniversityMafraq25113Jordan Departm.nt of Statistics Michael Okpara University of AgricultureUmudikeAbiaNigeria Jam.u and Kashm.r Institute of m.them.tical Sciences Srinagar190008India

In estim.tion theory,the researchers have put their efforts to develop som. estim.tors of population m.an which m.y give m.re precise results when adopting ordinary least squares(OLS)m.thod or robust regression techniques for estim.ting regression *** when the correlation is negative and the outliers are presented,the results can be distorted and the OLS-type estim.tors m.y give m.sleading estim.tes or highly biased ***,this paper m.inly focuses on such issues through the use of non-conventional m.asures of dispersion and a robust estim.tion ***,we have proposed generalized estim.tors by using the ancillary inform.tion of non-conventional m.asures of dispersion(Gini’s m.an difference,Downton’s m.thod and probabilityweighted m.m.nt)using ordinary least squares and then finally adopting the Huber m.estim.tion technique on the suggested *** proposed estim.tors are investigated in the presence of outliers in both situations of negative and positive correlation between study and auxiliary *** com.arisons and real data application are provided to show the strength of the proposed generalized *** is found that the proposed generalized Huber-m.type estim.tors are m.re efficient than the suggested generalized estim.tors under the OLS estim.tion m.thod considered in this *** new proposed estim.tors will be useful in the future for data analysis and m.king decisions.

关键词： Product estim.tors ratio estim.tors regression estim.tors ordinary least square Huber m m.an squared error efficiency

Advances in the m.nagem.nt of infertility in m.n with spinal cord injury

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Asian Journal of Andrology 2016年第3期18卷 382-390,I0007,I0008页

作者： Em.d ibrahim Nancy L Brackett Charles m.Lynne The m.am. Project to Cure Paralysis University of Miami Miller School of Medicine Miami FL USA Departm.nt of Urology University of Miami Miller School of Medicine Miami FL USA.

Couples with a spinal cord injured m.le partner require assisted ejaculation techniques to collect sem.n that can then be further used in various assisted reproductive technology m.thods to achieve a pregnancy. The m.jority of m.n sustaining a spinal cord injury regardless of the cause or the level of injury cannot ejaculate during sexual intercourse. Only a sm.ll m.nority can ejaculate by m.sturbation. Penile vibratory stim.lation and electroejaculation are the two m.st com.on m.thods used to retrieve sperm. Other techniques such as prostatic m.ssage and the adjunct application of other m.dications can be used, but the results are inconsistent. Surgical sperm.retrieval should be considered as a last resort if all other m.thods fail. Special attention m.st be paid to patients with T6 and rostral levels of injury due to the risk of autonom.c dysreflexia resulting from.stim.lation below the level of injury. Bladder preparation should be perform.d before stim.lation if retrograde ejaculation is anticipated. Erectile dysfunction is ubiquitous in the spinal cord injured population but is usually easily m.naged and does not pose a barrier to sem.n retrieval in these m.n. Sem.n analysis param.ters of m.n with spinal cord injury are unique for this population regardless of the m.thod of retrieval, generally presenting as norm.l sperm.concentration but abnorm.lly low sperm.m.tility and viability. When sperm.retrieval is desired in this population, em.hasis should be placed on initially trying the sim.le m.thods of penile vibratory stim.lation or electroejaculation before resorting to m.re advanced and invasive surgical procedures.

关键词： assisted reproductive technology ejaculation electroejaculation m.le infertility paraplegia penile vibratory stim.lation sem.n sperm spinal cord injury surgical sperm.retrieval

Exact Solutions of Nonlinear Evolution Equations in m.them.tical Physics Using the m.dified Sim.le Equation m.thod

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Chinese Physics Letters 2012年第6期29卷 1-4页

作者： E.m.E.Zayed S.A.Hoda ibrahim Departm.nt of m.them.tics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

The m.dified sim.le equation m.thod is em.loyed to construct the exact solutions involving param.ters of nonlinear evolution equations via the (1+1)-dim.nsional m.dified KdV equation,and the (1+1)-dim.nsional reaction-diffusion *** these param.ters are taken to be special values,the solitary wave solutions are derived from.the exact *** is shown that the proposed m.thod provides a m.re powerful m.them.tical tool for solving nonlinear evolution equations in m.them.tical physics.

关键词： equation. exact equation

Diagnostic Accuracy of Strain Im.ging of the Left Ventricle in Detection of Obstructive Coronary Artery Disease

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World Journal of Cardiovascular Diseases 2020年第8期10卷 572-586页

作者： m.ham.d Fahm. Elnoam.ny Waleed abdou ibrahim Ahm.d m.hm.ud Ham.a m.noufia University Menoufia Egypt m.halla Cardiac Center Gharbia Egypt

Background: Speckle tracking echocardiography using average global strain and strain rate (SR) param.ters for early detection of high risk patients with coronary artery disease (CAD) has gained a substantial clinical ... 详细信息

Background: Speckle tracking echocardiography using average global strain and strain rate (SR) parameters for early detection of high risk patients with coronary artery disease (CAD) has gained a substantial clinical interest. Objective: Assessment of the diagnostic accuracy of strain imaging of the left ventricle in detection of obstructive coronary artery disease. Methods: One hundred patients were enrolled. They were divided into 3 groups: Group I (n = 40 patients) presented with ST segment elevation myocardial infarction (STEMI), Group II (n = 40 patients) presented with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and Group III (n = 20 patients) with normal coronary angiography served as a control group. All patients were subjected to 2D speckle tracking echocardiography (2D STE) to assess LV longitudinal strain and strain rate (SR). Sensitivity, specificity and diagnostic accuracy of 2D STE in prediction of CAD and its severity using Gensini score were assessed. Results:m.ly:Verdana;"> The m.an age for Group I, II and III was 52.20 ± 11.83, 51.97 ± 14.53 and 52.75 ± 10.75 respectively. LV average global systolic strain (AGS) was significantly lower in group I and II when com.ared to group III. AGS and average global systolic SR showed significa

关键词： Coronary Artery Disease Left Ventricle Strain Im.ging

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沙里亚大法史及其在华的演化发展研究

沙里亚大法史及其在华的演化发展研究

作者： m.HAm.D ELSAYED ibrahim abdou 上海师范大学

学位级别：硕士

作为世界五大法系之一的沙里亚大法是一部包罗万象的宗教法规汇集,是一种将法律、伦理和教规紧密结合的宗教法。它由伊斯兰教基本原则检验,接替了古代罗马法、巴比伦法、波斯法和犹太法的某些习惯和法律传统,从而具备了较广泛的适应性,... 详细信息

作为世界五大法系之一的沙里亚大法是一部包罗万象的宗教法规汇集,是一种将法律、伦理和教规紧密结合的宗教法。它由伊斯兰教基本原则检验,接替了古代罗马法、巴比伦法、波斯法和犹太法的某些习惯和法律传统,从而具备了较广泛的适应性,被称为“宽容的法律”(al-Shari’ah al-Sam.ah),其内容涵盖了宗教、法律、经济、政治、伦理道德、军事、生活习俗等各个领域。在沙里亚大法学中,最根本的来源是《古兰经》,其次是圣训,所以它被称为“启示法律”或“圣神法律”。沙里亚大法是基本对立并独立于当时法律实践的法律学说体系而产生,其对人类社会的影响十分重大。沙里亚大法很早就引起世界上,尤其西方学术界的广泛关注,但长期以来尚未引起中国学术界的高度重视,近期正是在阿中双方学者的共同推动下,会出现前所未有的繁荣局面。在中国,以沙里亚大法这个概念为主题的作品十分鲜见,从全国论文期刊全文数据库中检索到有关沙里亚法的论文尚不足几篇,仅有的几篇也只限于研究沙里亚法的著作中个别章节的简单介绍,真正的专题研究论文更是凤毛麟角,对于沙里亚大法史及其在华的演化发展研究也无从查证。另外,信息传播手段中某些著作和网站对沙里亚大法这个概念的理解存在偏差和误解。为此,本文从较深地层面论述沙里亚大法的历史。沙里亚大法在时代和环境的变迁发展中不断做出适应性的调整,在历史的潮流中不断焕发出新的生机。对沙里亚大法在华延伸的状况进行学术研究,首先,要研究其从开始传入中国,历经唐、宋、元、明、清,随后进入民国并传播到今天的一个发展状态;其次,研究它为适应中国环境而演化出的,具有强烈中国特色的沙里亚习惯法。在中国这个多民族、多文化共存的社会中,各民族习惯法同国家法功能关系的协调是各族人民融洽相处的必要条件,因此需要调适两者之间的关系,在不违背国家法制定规范的大前提下,各民族遵守自己的习惯法。

关键词：沙里亚大法史习惯法穆菲提《古兰经》本土化中国