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SYNTHESIS,CHARACTERIZATION AND ENHANCED ELECTRICAL PROPERTIES OF CTAB-DIRECTED POLYANILINE NANOPARTICLES

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Chinese Journal of Polymer Science 2011年第2期29卷 181-190页

作者： Lal Said jan mohamed Ahmed Siddig Department of Physics Postgraduate College Mardan23200Khyber PakhtunkhwaPakistan School of Physics and Applied Physics Faculty of Science and TechnologyEL Neelain UniversityKhartoumSudan

Inverse microemulsion system of cetyltrimethylammonium bromide（CTAB） molecules is utilized for virtually monodispersed and controlled growth of HCl polyaniline（PANI） nanoparticles at room temperature（ca.300 K）.The templated electroconductive polymer reveals lamellar crystalline structure under X-ray diffraction signifying marked sub-chain alignment of the polymerized *** nanostructured polymer has spherically symmetric morphology in a size range of 2.0 nm to 6.0 nm under electron microscope *** permeation chromatography gives polydispersity index of 1.02 for nanostructured polymer in agreement with the size monodispersity transpired by electron *** *** conductivityσ_（dc） of PANI at room temperature is 10.11 S/cm whereas the variation of conductivity with temperature in the range 227-303 *** that the conducting mechanism can be considered as three-dimensional variable-range-hopping（3D-VRH）.UV-Vis spectrum indicates two broad absorption bands due to polaron formation that contributes to enhanced electrical conductivity of the *** fundamental absorption edge in the polymer is formed by direct allowed transitions to the extent that the optical band gap value was found to be 2.35 *** crystalline nanostructure and homogeneous doping attained in the cationic template of amphiphile are argued as contributing factors to the enhanced conductivity of the polymer.

关键词： Polyaniline Nanostructured Band gap energy Electrical conductivity

高温高压下Saraline基超轻完井液黏度预测模型优选

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石油勘探与开发 2016年第5期43卷 793-798页

作者： AMIR Zulhelmi jan badrul mohamed WAHAB Ahmad Khairi Abdul KHALIL Munawar ALI Brahim Si CHONG Wen Tong University of Malaya Center for Sustainable Infrastructure Development(CSID) University of Indonesia

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度... 详细信息

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度降幅较小,且黏度对压力变化不敏感。将实验测量数据与4个常用黏度-温度-压力模型进行拟合,发现利用改进型Mehrotra-Svreck模型和Ghaderi模型预测的黏度值与测量值吻合度较高,能够描述高温高压下Saraline基超轻完井液的黏度特性。与Sarapar基超轻完井液对比后发现,温度对Saraline基超轻完井液黏度的影响更小,压力对Saraline基超轻完井液黏度的影响可以忽略不计,改进型Mehrotra-Svreck模型和Ghaderi模型在各种温度和压力条件下对Saraline基超轻完井液的黏度预测精度优于对Sarapar基超轻完井液的黏度预测。

关键词：高温高压黏度预测超轻完井液 Saraline合成油欠平衡射孔

A Comparative Analysis of RAD and Agile Technique for Management of Computing Graduation Projects

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Computers, Materials & Continua 2020年第8期64卷 777-796页

作者： Fazal Qudus Khan Saim Rasheed Maged Alsheshtawi Tarig mohamed Ahmed Sadeeq jan Department of Information Technology FCITKing Abdulaziz UniversityJeddahSaudi Arabia University of Khartoum Department of Computer ScienceKhartoumSudan Department of Computer Science&IT University of Engineering and TechnologyPeshawarPakistan

Computing students face the problem with time and quality of the work while managing their graduation/senior *** Application Development(RAD)model is based on continual user involvement for the process of requirement gathering via *** each iteration,the developers can validate the requirements that are completed in the *** a project with RAD is easier but not *** the other hand,Agile project management techniques focus on flexibility,agility,teamwork and quality based on user *** user involvement is avoided,which requires extensive maintenance time for fixing iteration and release of the story *** also makes it necessary to provide onsite training to the users of the *** research provides the pros and cons of RAD and Agile project management techniques,to help students in deciding the best approach for managing their graduation *** the evaluation of these techniques,similar case studies were given to the senior project students(having similar CGPAs)for building similar functionality-based *** two projects“Life Organizer”developed and managed using RAD and“Smart Patient Assistant(SPA)”developed and managed through Agile methodology were evaluated against the quality assurance criteria for senior *** study found that the project developed with RAD methodology performed 13.33%better in providing extensive and elaborated documentation than the students following the Agile *** the other hand,SPA-Agile based project,due to teamwork had 2.5%better implementation than Life Organizer-RAD based project.

关键词： Rapid application development prototyping agile project management smart application development graduation project thesis

Traffic Queuing Management in the Internet of Things: An Optimized RED Algorithm Based Approach

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Computers, Materials & Continua 2021年第1期66卷 359-372页

作者： Abdul Waheed Naila Habib Khan Mahdi Zareei Shahab Ul Islam Latif jan Arif Iqbal Umar Ehab Mahmoud mohamed Department of Information Technology Hazara UniversityMansehra21120Pakistan School of Electrical and Computer Engineering Seoul National UniversitySeoul08826Korea Department of Computer Science Institute of Management SciencesPeshawar25000Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Computer Science IQRA National UniversityPeshawar25124Pakistan Department of Electrical Engineering University of Engineering TechnologyPeshawar25120Pakistan Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringAswan UniversityAswan81542Egypt

Congestion control is one of the main obstacles in cyberspace *** in internet traffic may cause several problems;such as high packet hold-up,high packet dropping,and low packet *** the course of data transmission for various applications in the Internet of things,such problems are usually generated relative to the *** tackle such problems,this paper presents an analytical model using an optimized Random Early Detection(RED)algorithm-based approach for internet traffic *** validity of the proposed model is checked through extensive simulation-based *** analysis is observed for different functions on internet *** performance metrics are taken into consideration,namely,the possibility of packet loss,throughput,mean queue length and mean queue *** sets of experiments are observed with varying simulation *** experiments are thoroughly analyzed and the best packet dropping operation with minimum packet loss is identified using the proposed model.

关键词： Random early detection(RED) active queue management(AQM) quality of service(QOS) throughput

A GIS-based approach for identifying potential sites for harvesting rainwater in the Western Desert of Iraq

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International Soil and Water Conservation Research 2018年第4期6卷 297-304页

作者： Ammar Adham Khamis Naba Sayl Rasha Abed mohamed Arbi Abdeladhim jan GWesseling Michel Riksen Luuk Fleskens Usama Karim Coen JRitsema Wageningen University Soil Physics and Land Management GroupP.O.Box476700AA Wageningenthe Netherlands Department of Civil and Structural Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600UKM BangiSe-langor Darul EhsanMalaysia Department of Dams and Water Resources Engineering CollegeUniversity of AnbarRamadiIraq Department of Civil Engineering Engineering CollegeUniversity of AnbarRamadiIraq Department of Civil Engineering and Management University of TwenteP.O.Box2177500AE Enschedethe Netherlands

People living in arid and semi-arid areas with highly variable rainfall and unforeseeable periods of droughts or floods are severely affected by water shortages and often have insecure livelihoods. The construction of dams in wadies to harvest rainwater from small watersheds and to induce artificial groundwater recharge is one of the solutions available to overcome water shortages in the Western Desert of Iraq. The success of rainwater harvesting (RWH) systems depends heavily on their technical design and on the identification of suitable sites. Our main goal was to identify suitable sites for dams using a suitability model created with ModelBuilder in ArcGIS 10.2. The model combined various biophysical factors: slope, runoff depth, land use, soil texture, and stream order. The suitability map should be useful to hydrologists, decision-makers, and planners for quickly identifying areas with the highest potential for harvesting rainwater. The implementation of this method should also support any policy shifts towards the widespread adoption of RWH.

关键词： GIS Rainwater harvesting Iraq's western desert Suitability map

An Infinite Elastic Plate Weakened by a Generalized Curvilinear Hole and Goursat Functions

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Applied Mathematics 2014年第4期5卷 728-743页

作者： mohamed Abdellah Abdou Azhar Rashad jan Department of Mathematics Alexandria University Alexandria Egypt Department of Mathematics Umm Al-Qura University Mecca KSA

Complex variables method has been used to solve the first and second fundamental problems for an infinite plate weakened by a generalized curvilinear hole C. The curvilinear hole is conformally mapped on the domain outside or inside a unit circle γ using a general rational mapping function with complex constants. Many special and new cases are derived from this work. Some of the work of the previous authors in this domain will be considered as special cases of this paper. Also the interesting cases when the shape of the hole takes different famous shapes are included. The components of stresses for some examples are obtained.

关键词： Goursat Functions Conformal Mapping Curvilinear Hole Stress Components

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高活度废放射源危险放射源的共同解决方法

国际原子能机构通报 2007年第2期 56-58页

作者： jan-Marie Potier mohamed Al-Mughrabi 国际原子能机构核燃料循环和废物技术处

移动式"热室"帮助各国保证高活度废放射源安全和安全地贮存它们。最近几年,对可能恶意使用放射性材料及其给人与环境带来的相关后果的担心显著地增加。有关核安全和核保安的故事经常成为世界媒体的头条新闻,所以政府和公众都自然比较容... 详细信息

移动式"热室"帮助各国保证高活度废放射源安全和安全地贮存它们。最近几年,对可能恶意使用放射性材料及其给人与环境带来的相关后果的担心显著地增加。有关核安全和核保安的故事经常成为世界媒体的头条新闻,所以政府和公众都自然比较容易接受确保放射性材料安全问题,无论这些材料可能出现在哪儿。于是,伴随着这种日益担心,全球开始增加对放射源的控制、衡算和保安,也就不足为奇了。

关键词：活度放射性材料核保安放射源安全恶意使用射源装置国际原子能机构世界媒体屏蔽体头条新闻

New Insight in the Assessment of Left Ventricular Function in Paradoxical Low Flow Aortic Stenosis Patients with Normal Left Ventricular Ejection Fraction: A Mini-Review

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World Journal of Cardiovascular Surgery 2020年第12期10卷 264-270页

作者： Sherif Baath Allah Enrico Mangieri jan Fedacko Petras Lohana Mohammed Elmahal Amena Elsaady Madian Abdelrahman Jaipaul Singh mohamed Khorshid Ram B. Singh Galaleldin Nagib Elkilany RAK Medical and Health Science University Masafi Hospital Masafi UAE Cardiac Catheterization Department Sapienza University Rome Italy Internal Medicine Department Pavol Jozef Safárik University Kosice Slovakia Internal Medicine Department Masafi Hospital Fujairah UAE London University London UK Masafi Hospital Masafi UAE Oslo University Oslo Norway School of Natural Sciences University of Central Lancashire Preston UK Faculty of Medicine Zagazig University Zagazig Egypt Halberg Hospital and Research Institute Moradabad India Gulf Medical University Ajman UAE ARE AMMC Tanta University Dubai UAE

Paradoxical valvular aortic stenosis (VAS) is a challenging area of clinical cardiology for the practitioners. It involves a small aortic valve area, low flow rate and mean pressure gradient although there is normal left ventricular ejection fraction. The aim of this study was to assess left ventricular (LV) dysfunction in a symptomatic severe aortic valve stenosis which is of crucial importance in identifying patients at risk of heart failure, postoperative complications and increased mortality. There are new insights which are involved in assessment of LV myocardial function including global longitudinal strain (GLS) by two-dimensional speckle tracking echocardiography (2D STE), myocardial performance index (MPI) and maximum rate of LV pressure rise (+dP/dt) during isovolumetric contraction time of the LV. This information can provide both diagnostic and prognostic information in addition to standard echocardiographic and clinical parameters. However, a profound understanding of the complex interaction between loading conditions, chamber geometry and contractility is necessary for the correct interpretation of myocardial deformation in order to draw appropriate conclusions in patients with aortic valve disease. This mini review is related to new and novel insights into the assessment of left ventricular function (LVF) in paradoxical low flow aortic stenosis patients with normal left ventricular ejection fraction (LVEF).

关键词： Aortic Stenosis LVEF Aortic Valve Myocardial Function Global Longitudinal Stain Echocardiography

Surgical Treatment of Gynaecomastia: A Prospective Study in 75 Patients

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Surgical Science 2015年第11期6卷 506-517页

作者： Adel M. Tolba mohamed Nasr Plastic Surgery Unit General Surgery Zagazig University Zagazig Egypt

Introduction: Gynaecomastia is a benign enlargement of male breast;many techniques have been described for management but none have gained universal acceptance. We discuss the outcomes of the surgical management of gynaecomastia and assess the morbidity and complication rates associated with the procedure to determine whether certain surgical techniques produce better outcomes. Materials and Methods: 75 patients with gynaecomastia were operated in our hospital during the period from jan. 2009 to jan. 2015. Results: A total of 140 breasts were operated on during the study period. Patients underwent either liposuction alone (20 breasts), excision alone (70 breasts), both excision and liposuction (36 breast) or skin reduction procedure (14 breasts). 19 operated breasts (13.4%) experienced some form of complications. Minor complications included seroma (4 patients), superficial wound dehiscence (3 patients) and two patients developed haematomas requiring evacuation in theatre. Unsatisfactory cosmotic result was present in 10 breasts and surgical revision was done in 5 breasts. Simon grade 111 breasts experienced the highest complication rate. Conclusion: The study has found that moderate sized gynaecomastia whether true or pseudo gynaecomastia with mild to moderate breast redundancy can be managed easily and effectively by liposuction alone or combined with glandular resection while the conventional infraareolar subcutaneous mastectomy still gives satisfactory results and with no need to remove extra skin. On the other hand, large gynaecomastia with severe breast redundancy can be treated effectively by the inferior pedicle technique without vertical scar.

关键词： Gynaecomastia Male Breast Surgical Management