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Recalculate Structural, elastic, electronic, and Thermal Properties in LaAlO<sub>3</sub>Rhombohedral Perovskite

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Advances in Materials Physics and Chemistry 2013年第2期3卷 146-152页

作者： Abdelkader Boudali Fatiha Saadaoui Mostefa Zemouli mohamed Driss Khodja Kadda Amara Laboratory of Physico-chemical Studies University of Saida Saida Algeria

We study the structural, elastic and electronic properties of perovskite insulator LaAlO3 using two different methods: the full-potential linearized augmented plane wave method and the pseudo-potential plane wave scheme in the frame of generalized gradient approximation and local density approximation GGA + mBJ. We have evaluated the ground state quantities. Also, we have presented the results of the band structure and densities of states. These results are in favourable agreement with previous theoretical works and the existing experimental data. To complete the fundamental characteristics of this compound, we have analyzed the thermodynamic properties.

关键词： Ab-Initio Calculations elastic Properties electronic Structure Thermodynamic

Inhibitory activities of microalgal extracts against Epstein-Barr virus DNA release from lymphoblastoid cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第5期12卷 335-345页

作者： Yih-Yih KOK Wan-Loy CHU Siew-Moi PHANG Shar Mariam mohamed Rakesh NAIDU Pey-Jiun LAI Shui-Nyuk LING Joon-Wah MAK Patricia Kim-Chooi LIM Pauline BALRAJ Alan Soo-Beng KHOO Division of Human Biology International Medical University Institute of Biological Sciences Faculty of Scienceand Institute of Ocean and Earth Sciences(IOES)University of Malaya Faculty of Medicine University of Malaya School of Medicine and Health Sciences Monash University Molecular Pathology Unit Institute for Medical ResearchJalan Pahang

This study aimed to assess the inhibitory activities of methanol extracts from the microalgae Ankistrodesmus convolutus,Synechococcus elongatus,and Spirulina platensis against Epstein-Barr virus(EBV) in three Burkitt's lymphoma(BL) cell lines,namely Akata,B95-8,and *** antiviral activity was assessed by quantifying the cell-free EBV DNA using real-time polymerase chain reaction(PCR) *** methanol extracts from Ankistrodesmus convolutus and Synechococcus elongatus displayed low cytotoxicity and potent effect in re-ducing cell-free EBV DNA(EC5028 000).After fractionation by column chromatography,the fraction from Synechococcus elongatus(SEF1) reduced the cell-free EBV DNA most effectively(EC50=2.9 μg/ml,therapeutic index>69).Upon further fractionation by high performance liquid chromatography(HPLC),the sub-fraction SEF1'a was most active in reducing the cell-free EBV DNA(EC50=1.38 μg/ml,therapeutic index>14.5).This study suggests that microalgae could be a potential source of antiviral compounds that can be used against EBV.

关键词： Microalgae Ankistrodesmus convolutus Synechococcus elongatus Spirulina platensis Lymphoblastoid cells Epstein-Barr virus(EBV)

Newton-EGMSOR Methods for Solution of Second Order Two-Point Nonlinear Boundary Value Problems

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Journal of Mathematics and System Science 2012年第3期2卷 185-190页

作者： Jumat Sulaiman Mohd Khatim Hasan mohamed Othman Samsul Ariffin Abdul Karim School of Science and Technology Universiti Malaysia Sabah Kota Kinabalu 88400 Sabah Malaysia School of Information Technology Universiti Kebangsaan Malaysia UKM Bangi 43600 Selangor Malaysia Department of Communication Technology and Network Universiti Putra Malaysia UPM Serdang 43400 Selangor Malaysia Department of Fundamental and Applied Sciences Universiti Teknologi Petronas Tronoh 31750 Perak Darul Ridzuan Malaysia

The convergence results of block iterative schemes from the EG （Explicit Group） family have been shown to be one of efficient iterative methods in solving any linear systems generated from approximation equations. Apart from block iterative methods, the formulation of the MSOR （Modified Successive Over-Relaxation） method known as SOR method with red-black ordering strategy by using two accelerated parameters, ω and ω′, has also improved the convergence rate of the standard SOR method. Due to the effectiveness of these iterative methods, the primary goal of this paper is to examine the performance of the EG family without or with accelerated parameters in solving second order two-point nonlinear boundary value problems. In this work, the second order two-point nonlinear boundary value problems need to be discretized by using the second order central difference scheme in constructing a nonlinear finite difference approximation equation. Then this approximation equation leads to a nonlinear system. As well known that to linearize nonlinear systems, the Newton method has been proposed to transform the original system into the form of linear system. In addition to that, the basic formulation and implementation of 2 and 4-point EG iterative methods based on GS （Gauss-Seidel）, SOR and MSOR approaches, namely EGGS, EGSOR and EGMSOR respectively are also presented. Then, combinations between the EG family and Newton scheme are indicated as EGGS-Newton, EGSOR-Newton and EGMSOR-Newton methods respectively. For comparison purpose, several numerical experiments of three problems are conducted in examining the effectiveness of tested methods. Finally, it can be concluded that the 4-point EGMSOR-Newton method is more superior in accelerating the convergence rate compared with the tested methods.

关键词： Explicit group MSOR iteration second order scheme two-point nonlinear boundary value problem.

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苏丹学生汉语被字句习得偏误分析及教学对策

苏丹学生汉语被字句习得偏误分析及教学对策

作者：穆罕默德（mohamed Rabei）西北师范大学

学位级别：硕士

被字句是汉语语法中的一种重要句型,是汉语作为第二语言教学的重点与难点,也是研究者和学者考察的重点。本文通过对苏丹学生进行的调查,从句法、语用这两方面出发,总结苏丹学生学习汉语被字句时经常出现的错误并进行偏误分析。本文对被... 详细信息

被字句是汉语语法中的一种重要句型,是汉语作为第二语言教学的重点与难点,也是研究者和学者考察的重点。本文通过对苏丹学生进行的调查,从句法、语用这两方面出发,总结苏丹学生学习汉语被字句时经常出现的错误并进行偏误分析。本文对被字句教学提出一些意见与看法,有助于我日后从事汉语作为第二语言的教学,也有利于苏丹学生学习汉语“被”字句研究。本文共七章,第一章绪论,介绍现代汉语“被”字句研究综述和本文的选题目的和意义、研究的创新点、采用的研究方法;第二章介绍汉语被字句的特征。第三章介绍问卷统计及调查结果第四章介绍被字句偏误与偏误类型;第五章介绍偏误的形式原因六章对教材编写和教学提出意见。第七章结语,对本文的研究内容进行概括总结,指出本文研究的创新之处以及不足之处,以待更深入地研究。

关键词：被字句汉语作为第二语言教学偏误分析教学对策

Radial heat transport in packed beds-I： Experimental investigation of heat transfer coefficients of pellets and monolith catalysts at atmospheric and high pressures

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Journal of Chemistry and Chemical Engineering 2009年第6期3卷 1-14页

作者： mohamed A. Al-Meshragi Hadi A. elakrami Hesham G. Ibrahim Chemical Engineering Department Faculty of Engineering Al-Fatah University Tripoli Libya Chemical Engineering Department Faculty of Engineering Al-Mergheb University Al-Khoms 40161 Libya

The effect of operating pressure on the radial heat transfer coefficients, in a non-adiabatic fixed packed bed was studied at atmospheric and higher pressures, The study was concerned with investigating the effect of the pressure on the radial thermal conductivity （K^r） and wall heat transfer coefficient （h~） for both pellets and monolith catalysts. The study included beds that were packed with pellets and monoliths, separately. The radial temperature distribution was measured at different beds heights and feed flow rates for both types of packing. Steady-state temperatures were measured using nine chromel-alumel thermocouples arranged on a stainless steel-cross. After temperatures were collected, the radial thermal conductivity and wall heat transfer coefficient were calculated using a two-dimensional pseudo-homogeneous model. The results showed that, the radial temperature profile at the entrance of the heating section was nearly even, and a constant temperature along the radius （0F/0r=0） taken as a boundary condition to solve the partial differential equation controlling the heat transfer. Temperature profiles obtained at elevated pressures were smoother at the center of the reactor and increased sharply near the wall, than profiles at atmospheric pressure. It could also be observed, that the radial temperature profiles in the center of the reactor using a monolith catalyst at elevated pressure were more even and smoother than those of pellets. Temperature profiles in fixed beds were found to be very sensitive to Ker and hw. In pressures between atmospheric and 10 bars, there was no change in the effective heat transport parameters （i.e. they are independent of pressure in this range）. Both parameters were strongly affected by the pressure changes, above 10 bars. For the same Reynolds number （Ker） increased by 27% and 53% at 11 and 20 bars, respectively, in pellets catalyst. And they increased by factors of 2.3 and 4, when the pressure increased to the same press

关键词： heat transfer packed beds pseudo-homogeneous model pressure effect

Semi-Conducting Behavior of Plio-Quaternary Basaltic Lava Flows from Hemat Madam Volcano, Sana’a-Amran Volcanic Field, Yemen

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Journal of Applied Mathematics and Physics 2015年第12期3卷 1610-1618页

作者： M. R. Eraky mohamed Th. S. Heikal Physics Department Faculty of Science Kafelsheikh University Kafr El-Sheikh Egypt Geology Department Faculty of Science Tanta University Tanta Egypt

electric DC and AC measurements and dielectric investigations have been carried out on some Plio-Qaternary basalt of Hemat Madam volcano from Sana’a-Amran volcanic field (SAVF). In this article we focus primarily on the field aspects and the main characteristic mineralogical and petrographic features of this inactive volcano. Using DC and AC experimental arrangements we discovered excellent electrical characteristics for this inactive volcano. The results of DC electrical resistivity versus a temperature reveal that all the samples have semiconductor characters. Moreover, the measurements showed that these samples have high resistive extrinsic semiconductors (ρDC ~ 109 Ω·m). AC and dielectric measurements were ensured the semi-conductivity and normal dielectric behavior of these samples. AC measurements reveal that the classical barrier hopping model (CBH) is the predominant conduction mechanism, while at low temperature region small polarons may contribute to the conduction in the samples. The samples have low values for dielectric constant ε' and low loss factor tanδ (ε' ~ 27 and tanδ ~ 0.7 at 200 Hz for the sample BA7). Then, the semicodutor behavior, the high values of DC/AC resistivity and low loss dissipation factor considered a very good characterization for magnetic semiconductor materials. So, we can predict that, the studied natural materials represent newborn promising material sciences for many more technological applications.

关键词： Hemat Madam Volcano Semiconductor Basaltic Rocks electrical Properties

Postoperative Use of Dopamine Agonist in Controlling the Residual Mass in Non Functioning Pituitary Adenoma

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Open Journal of Modern Neurosurgery 2020年第2期10卷 267-274页

作者： mohamed Mahmoud Ahmad A. Moussa Ahmad elsayed Abokresha Hazem A. Yousef Department of Neurosurgery Assiut University Hospital Assiut Egypt Department of Neurosurgery Queen Elizabeth Hospital Birmingham UK Department of Radiology Assiut University Hospital Assiut Egypt

Background: Non-functioning pituitary adenoma (NFPA) is a challenging tumor. It is usually reached to a large size before it is clinically manifested. Operative interference is the first option in treatment of large NFPA causing compressive manifestations but with frequent postoperative residual masses that is usually required additional treatment. Postoperative radiotherapy carried frequent side effects which open the door for postoperative medical treatment with dopamine agonist (DA) drugs based on the fact that these tumors have a variable amount of dopamine receptors. Lack of randomized, placebo-controlled trials prevents any conclusion on the efficacy of this drug. Its role in controlling postoperative proliferation and decreasing the rate of recurrence of NFPA is still questionable. Objective: Efficacy of bromocriptine (dopamine agonist (DA) drug) in reducing or preventing the re-growth of non-functioning pituitary adenoma NFPA after surgery. Methods: In this study, we examined the outcome of treating NFPA after surgery, with bromocriptine (dopamine agonists drug). This study was a retrospective review of consecutive patients that were treated by the authors at Assiut University Hospital between 2012-2018. All patients had postoperative Bromocriptine in a dose of 2.5 mg twice daily. Results: Thirty two patients were included in this study after they had surgery for NFPA. All patients had a residual mass documented by the immediate post operative MRI. After 6 months of postoperative bromocriptine treatment, and with comparing to immediate post operative images, eleven patients (34%) had mass reduction, thirteen patients (41%) of their residual masses remained unchanged and eight patients (25%) of the mass showed slight increase in size but not required re-surgery. After two years and throughout the follow up period, seven patients (22%) (all were males) had complete disappearance of the mass;ten patients (31%) had more reduction of the size of the mass (two of

关键词： Dopamine Agonists (DA) Non-Functioning Pituitary Adenoma (NFPA)

Effect of Plastic Deformation on Microstructure, Hardness and electrical Properties of 3003 Aluminum Alloys

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材料科学与工程（中英文B版） 2012年第8期2卷 458-463页

作者： mohamed Osman Abdel-Hamed Nasser Abdel-Azeem Kamel Safwat Ahmed Aly Faculty of Science Physics Department El-Minia University Egypt

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马里棉花在国际市场出口贸易竞争力研究

马里棉花在国际市场出口贸易竞争力研究

作者：托里（TOURE mohamed）华中农业大学

学位级别：硕士

马里种植的棉花是该国的重要经济资源。而且,它也为不同数量的家庭创造了收入。本研究的主要目的是调查2000-2013年期间马里棉花出口(MCE)在国际贸易市场的表现。使用竞争地位进行定量分析,采用简单的线性回归来衡量实际和估计的数量和... 详细信息

马里种植的棉花是该国的重要经济资源。而且,它也为不同数量的家庭创造了收入。本研究的主要目的是调查2000-2013年期间马里棉花出口(MCE)在国际贸易市场的表现。使用竞争地位进行定量分析,采用简单的线性回归来衡量实际和估计的数量和价格。而重力模型则用于衡量经济总体。国际市场对MCE竞争力的研究表明,2013年和2000年的马里棉出口分别占出口总额的1.7%和2.9%,平均增长率为-41.38%。据报,2001年马里的棉花出口量最大,占世界棉花出口量的3.4%。MCE在世界市场的竞争不依赖价格、生产或质量,而是由于国际市场贸易政策的波动。结果显示,在主要进口国家中,与其他竞争对手相比马里的棉花进口数量较少。线性回归表明:马里对美国出口的棉花价格变动的比率和贸易额之间存在着负相关但显着的联系。随着比例的上升(1%),马里棉花出口量的下降幅度接近14220吨。回归结果也显示,马里出口价格的正相关程度和显着影响。去年由于价格上涨,该国取得了西非国家主要生产国的地位。竞争分析也表明了在法国、西班牙、中国、印度、德国和葡萄牙市场,MCE能力有所增加。这项研究证明了将马里棉花困难增加到比利时市场。

关键词：马里棉花出口贸易业绩世界市场不稳定系数重力模型