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Chinese Chemical Letters 2008年第11期19卷 1301-1304页

作者： Ali Reza Kiasat rashid Badri Soheil Sayyahi Chemistry Department College of ScienceShahid Chamran UniversityAhvaz 61357-4-3169Iran

A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide （TBAB） as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification.

关键词： Alkyl thiocyanate Alkyl halide Tetrabutylammonium bromide Phase transfer catalyst Synthesis of alkyl thiocyanates

Shape Effect of Nanoparticles on Nanofluid Flow Containing Gyrotactic Microorganisms

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 483-494页

作者： Umair rashid Azhar Iqbal Abdullah M.Alsharif School of Mathematical Sciences Jiangsu UniversityZhenjiang212013China Department of Mathematics and Natural Sciences Prince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Department of Mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia

In this paper,we discussed the effect of nanoparticles shape on bioconvection nanofluid flow over the vertical cone in a permeable *** nanofluid contains water,Al2O3 nanoparticles with sphere(spherical)and lamina(non-spherical)shapes and motile *** phenomena of heat absorption/generation,Joule heating and thermal radiation with chemical reactions have been *** similarity transformations technique is used to transform a governing system of partial differential equations into ordinary differential *** numerical bvp4c MATLAB program is used to find the solution of ordinary differential *** interesting aspects of pertinent parameters on mass transfer,energy,concentration,and density of themotilemicroorganisms’profiles are computed and *** analysis depicts that the performance of sphere shape nanoparticles in the form of velocity distribution,temperature distribution,skin friction,Sherwood number and Motile density number is better than lamina(non-spherical)shapes nanoparticles.

关键词： Nanoparticle shape nanofluid numerical technique gyrotactic microorganisms magnetohydrodynamics

Reinforcement Learning-Based Optimization for Drone Mobility in 5G and Beyond Ultra-Dense Networks

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Computers, Materials & Continua 2021年第9期68卷 3807-3823页

作者： Jawad Tanveer Amir Haider rashid Ali Ajung Kim School of Optical Engineering Sejong UniversitySeoul05006Korea School of Intelligent Mechatronics Engineering Sejong UniversitySeoul05006Korea

Drone applications in 5th generation(5G)networks mainly focus on services and use cases such as providing connectivity during crowded events,human-instigated disasters,unmanned aerial vehicle traffic management,internet of things in the sky,and situation awareness.4G and 5G cellular networks face various challenges to ensure dynamic control and safe mobility of the drone when it is tasked with delivering these *** drone can fly in three-dimensional *** drone connectivity can suffer from increased handover cost due to several reasons,including variations in the received signal strength indicator,co-channel interference offered to the drone by neighboring cells,and abrupt drop in lobe edge signals due to antenna *** baseline greedy handover algorithm only ensures the strongest connection between the drone and small cells so that the drone may experience several *** for fast environment learning,machine learning techniques such as Q-learning help the drone fly with minimum handover cost along with robust *** this study,we propose a Q-learning-based approach evaluated in three different *** handover decision is optimized gradually using Q-learning to provide efficient mobility support with high data rate in time-sensitive applications,tactile internet,and haptics *** results demonstrate that the proposed algorithm can effectively minimize the handover cost in a learning *** work presents a notable contribution to determine the optimal route of drones for researchers who are exploring UAV use cases in cellular networks where a large testing site comprised of several cells with multiple UAVs is under consideration.

关键词： 5G dense network small cells mobility management reinforcement learning performance evaluation handover management

Impact of Nitrogen, Phosphorus and Potassium on Brown Planthopper and Tolerance of Its Host Rice Plants

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Rice science 2016年第3期23卷 119-131页

作者： Md Mamunur rashid Mahbuba JAHAN Khandakar Shariful ISLAM Plant Physiology Division Bangladesh Rice Research Institute Department of Entomology Bangladesh Agricultural University

The brown planthopper(BPH),Nilaparvata lugens(St?l),appeared as a devastating pest of rice in Asia. Experiments were conducted to study the effects of three nutrients,nitrogen(N),phosphorus(P) and potassium(K),on BPH and its host rice plants. Biochemical constituents of BPH and rice plants with varying nutrient levels at different growth stages,and changes in relative water content(RWC) of rice plants were determined in the laboratory. Feeding of BPH and the tolerance of rice plants to BPH with different nutrient levels were determined in the nethouse. Concentrations of N and P were found much higher in the BPH body than in its host rice plants,and this elemental mismatch is an inherent constraint on meeting nutritional requirements of BPH. Nitrogen was found as a more limiting element for BPH than other nutrients in rice plants. Application of N fertilizers to the rice plants increased the N concentrations both in rice plants and BPH while application of P and K fertilizers increased their concentrations in plant tissues only but not in BPH. Nitrogen application also increased the level of soluble proteins and decreased silicon content in rice plants,which resulted in increased feeding of BPH with sharp reduction of RWC in rice plants ultimately caused susceptible to the pest. P fertilization increased the concentration of P in rice plant tissues but not changed N,K,Si,free sugar and soluble protein contents,which indicated little importance of P to the feeding of BPH and tolerance of plant against BPH. K fertilization increased K content but reduced N,Si,free sugar and soluble protein contents in the plant tissues which resulted in the minimum reduction of RWC in rice plants after BPH feeding,thereby contributed to higher tolerance of rice plants to brown planthopper.

关键词： Nilaparvata lugens relative water content host tolerance nitrogen phosphorus potassium rice nutrient subsidy

Preparation and properties of chitosan–metal complex：Some factors influencing the adsorption capacity for dyes in aqueous solution

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Journal of Environmental Sciences 2018年第4期30卷 301-309页

作者： Sadia rashid Chensi Shen Jing Yang Jianshe Liu Jing Li College of Environmental Science and Engineering Donghua University Shanghai 201620 China State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry Shanghai 201620 China Beijing Enterprises Water Group (China) Investment Limited Beijing 100102 China

Chitosan–metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan–metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan–Fe（ Ⅲ） complex prepared by sulfate salts exhibited the best adsorption efficiency（100%） for various dyes in very short time duration（10 min）, and its maximum adsorption capacity achieved 349.22 mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan–metal complex. SO4^（2-） ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis ***, the p H sensitivity and the sensitivity of ionic environment for chitosan–metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan–metal complex can help not only in optimizing its use but also in designing new chitosan–metal based complexes.

关键词： Chitosan–metal complex Dye removal Coordination anion Adsorption optimization Crosslinking

Tanzania’s Foreign Policy Towards Kenya Since 2010

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Tanzania’s Foreign Policy Towards Kenya Since 2010

作者： rashid,rashid Moh’d 华中师范大学

学位级别：硕士

长期以来,坦桑尼亚一是东非外交事务的前沿阵地,并在非洲东部地区地区发挥了领导性作用。自2004年以来,坦桑尼亚的外交政策逐渐由解放外交转向经济外交。坦桑尼亚对肯尼亚的外交政策对两国人民生活的各个方面都产生了影响,其中包括政治... 详细信息

长期以来,坦桑尼亚一是东非外交事务的前沿阵地,并在非洲东部地区地区发挥了领导性作用。自2004年以来,坦桑尼亚的外交政策逐渐由解放外交转向经济外交。坦桑尼亚对肯尼亚的外交政策对两国人民生活的各个方面都产生了影响,其中包括政治影响、社会影响和经济影响。坦桑尼亚的外交政策主要体现在它会向肯尼亚公司的投资、贸易和安全做出指示。坦桑尼亚的外交政策为巩固睦邻政策、促进非洲统一、加快工业化进程与经济发展指明了方向。在东非国家中,肯尼亚是坦桑尼亚的重要合作伙伴之一,因为与其他东非国家相比,肯尼亚对坦桑尼亚的贸易额和投资额要高出许多。坦桑尼亚政府制定了法律和法规来规范与肯尼亚的跨境贸易,并为肯尼亚政府和私人投资者在坦桑尼亚的投资创造了有利的环境。坦赞两国政府都致力于解决其经济问题,进一步促进两国经济的发展。坦桑尼亚对肯尼亚的外交政策将东非地区的的工业化和区域建设作为重中之重。坦桑尼亚的外交政策积极解决了肯尼亚不安全的困境,并与肯尼亚携手共同解决与肯尼亚部落、野生生物走私和矿物开采问题有关的犯罪。因此,坦桑尼亚对肯尼亚的外交政策不仅为该地区的经济发展做出了巨大贡献,也为维护东非地区国家之间的团结、和平与安全做出了巨大贡献。

关键词：外教政策双边关系经济发展

Radio resource management in energy harvesting cooperative cognitive UAV assisted IoT networks:A multi-objective approach

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Digital Communications and Networks 2024年第4期10卷 1088-1102页

作者： Muhammad rashid Ramzan Muhammad Naeem Omer Chughtai Waleed Ejaz Mohammad Altaf Department of Electrical and Computer Engineering COMSATS University Islamabad(CUI)Wah CampusPakistan Department of Electrical Engineering Lakehead UniversityBarrieONL4M 3X9Canada

Cooperative communication through energy harvested relays in Cognitive Internet of Things(CIoT)has been envisioned as a promising solution to support massive connectivity of Cognitive Radio(CR)based IoT devices and to achieve maximal energy and spectral efficiency in upcoming wireless *** this work,a cooperative CIoT system is contemplated,in which a source acts as a satellite,communicating with multiple CIoT devices over numerous *** Aerial Vehicles(UAVs)are used as relays,which are equipped with onboard Energy Harvesting(EH)*** adopted a Power Splitting(PS)method for EH at relays,which are harvested from the Radio frequency(RF)*** conjunction with this,the Decode and Forward(DF)relaying strategy is used at UAV relays to transmit the messages from the satellite source to the CIoT *** developed a Multi-Objective Optimization(MOO)framework for joint optimization of source power allocation,CIoT device selection,UAV relay assignment,and PS ratio *** formulated three objectives:maximizing the sum rate and the number of admitted CIoT in the network and minimizing the carbon dioxide *** MOO formulation is a Mixed-Integer Non-Linear Programming(MINLP)problem,which is challenging to *** address the joint optimization problem for an epsilon optimal solution,an Outer Approximation Algorithm(OAA)is proposed with reduced *** simulation results show that the proposed OAA is superior in terms of CIoT device selection and network utility maximization when compared to those obtained using the Nonlinear Optimization with Mesh Adaptive Direct-search(NOMAD)algorithm.

关键词： Cooperative communication Energy harvesting Power splitting Unmanned aerial vehicles Cognitive radio Internet of things Multi-objective optimization Relay assignment Power allocation

MotViz: A Tool for Sequence Motif Prediction in Parallel to Structural Visualization and Analyses

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Genomics, Proteomics & Bioinformatics 2012年第1期10卷 35-43页

作者： Muhammad Sulaman Nawaz Sajid rashid National Center for Bioinformatics Quaid-i-Azam University Islamabad 44000 Pakistan

Linking similar proteins structurally is a challenging task that may help in finding the novel members of a protein family. In this respect, identification of conserved sequence can facilitate understanding and classifying the exact role of proteins. However, the exact role of these conserved elements cannot be elucidated without structural and physiochemical information. In this work, we present a novel desktop application MotViz designed for searching and analyzing the conserved sequence segments within protein structure. With MotViz, the user can extract a complete list of sequence motifs from loaded 3D structures, annotate the motifs structurally and analyze their physiochemical properties. The conservation value calculated for an individual motif can be visualized graphically. To check the efficiency, predicted motifs from the data sets of 9 protein families were analyzed and Mot^z algorithm was more efficient in comparison to other online motif prediction tools. Furthermore, a database was also integrated for storing, retrieving and performing the detailed functional annotation studies. In summary, MotViz effectively predicts motifs with high sensitivity and simultaneously visualizes them into 3D strucures. Moreover, Mot- V/z is user-friendly with optimized graphical parameters and better processing speed due to the inclusion of a database at the back end. MotViz is available at http：//***/***.

关键词： MotViz sequence motif structural visualization algorithm bioinformatics

Modernity in tradition： Reflections on building design and technology in the Asian vernacular

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Frontiers of Architectural Research 2015年第1期4卷 46-55页

作者： Mamun rashid Dilshad Rahat Ara Department of Architectural Engineering (AE) University of Shauah PO BOX 27272 Sharjah United Arab Emirates Department of Architectural Engineering (AE) United Arab Emirates University (UAEU) PO BOX 15551 AlAin United Arab Emirates

Vernacular buildings across the globe provide instructive examples of sustainable solutions to building problems. Yet, these solutions are assumed to be inapplicable to modern buildings. Despite some views to the contrary, there continues to be a tendency to consider innovative building technology as the hallmark of modern architecture because tradition is commonly viewed as the antonym of modernity. The problem is addressed by practical exercises and fieldwork studies in the application of vernacular traditions to current problems. This study investigates some aspects of mainstream modernist design solutions and concepts inherent in the vernacular of Asia, particularly that of the Chittagong Hill Tracts （CHT）. This work hinges on such ideas and practices as ecological design, modular and incremental design, standardization, and flexible and temporal concepts in the design of spaces. The blurred edges between the traditional and modern technical aspects of building design, as addressed by both vernacular builders and modern architects, are explored.

关键词： Building technotogy Tradition-modernity Innovation Vernaculararchitecture

Early-onset colorectal cancer:Current insights and future directions

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World Journal of Gastrointestinal Oncology 2022年第1期14卷 230-241页

作者： Claudia Wing-Kwan Wu rashid N Lui Division of Gastroenterology and Hepatology Department of Medicine and TherapeuticsThe Chinese University of Hong KongHong KongChina Department of Clinical Oncology The Chinese University of Hong KongHong KongChina

Early-onset colorectal cancer(EOCRC)has seen an alarming rise worldwide over the past two *** reason for this global trend is poorly *** appears to have its own unique clinical and molecular features when compared with late-onset colorectal *** patients appear to have more distal or rectal disease,a more advanced stage of disease at presentation,and more unfavorable histological *** risk factors for EOCRC is the first step in mitigating the rising burden of this *** we summarize several noteworthy biological factors and environmental exposures that are postulated to be responsible *** can hopefully translate in clinical practice to the development of better risk stratification tool for identifying highrisk individuals for early colorectal cancer screening,and identifying areas needed for further research to curb this rising trend.

关键词： Early-onset colorectal cancer Young-onset colorectal cancer Risk factors Environmental exposures Microbiome Genetics