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Tuning the electronic structure of the earth-abundant electrocatalysts for oxygen evolution reaction(OER)to achieve efficient alkaline water splitting-A review

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Journal of Energy Chemistry 2021年第5期30卷 299-342页

作者： mohammed-ibrahim Jamesh Moussab Harb Department of Physics and Materials Science City University of Hong KongTat Chee AvenueKowloonHong KongChina Applied and Plasma Physics School of Physics(A28)University of SydneySydneyNSW 2006Australia KAUST Catalysis Center(KCC) Physical Sciences and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Tuning the electronic structure of the electrocatalysts for oxygen evolution reaction(OER)is a promising way to achieve efficient alkaline water splitting for clean energy production(H2).At first,this paper introduces the significance of the tuning of electronic structure,where modifying the electronic structure of the electrocatalysts could generate active sites having optimal adsorption energy with OER intermediates,and that could diminish the energy barrier for OER,and that could improve the activity for ***,this paper reviews the tuning of electronic structure along with catalytic performances,synthetic methodologies,chemical properties,and DFT calculations on various nanostructured earth-abundant electrocatalysts for OER in alkaline ***,this review discusses the tuning of the electronic structure of the several nanostructured earth-abundant electrocatalysts including oxide,(oxy)hydroxide,layered double hydroxide,alloy,metal phosphide/phosphate,nitride,sulfide,selenide,carbon containing materials,MOF,core-shell/hetero/hollow structured materials,and materials with vacancies/defects for OER in alkaline environment(including activity:overpotential(η)of ≤200 mV at10 m A cm^(-2);stability:≥100 h;durability:≥5000 cycles).Then,this review discusses the robust stability of the electrocatalysts for OER towards practical ***,this review discusses the in situ formation of thin layer on the catalyst surface during *** addition,this review discusses the influence of the adsorption energy of the OER intermediates on OER performance of the ***,this review summarizes the various promising strategies for tuning the electronic structure of the electrocatalysts to achieve enhanced performance for OER in alkaline environment.

关键词： OER electrocatalyst Electrochemical water splitting Earth abundant electrocatalyst Hydrogen energy

Implementation Study of Dynamic Load Balancing Algorithm of Parallel Tree Computation 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： mohammed A.M. ibrahim M.SaifMokbel Faculty of Engineering Department of Software Engineering Taiz University Republic of Yemen Taiz city P. O.Box:6038

The rapid growth of interconnected high performance workstations has produced a new computing paradigm called clustered of workstations computing. In these systems load balance problem is a serious impediment to achieve good performance. The main concern of this paper is the implementation of dynamic load balancing algorithm, asynchronous Round Robin (ARR), for balancing workload of parallel tree computation depth-first-search algorithm on Cluster of Heterogeneous Workstations (COW) Many algorithms in artificial intelligence and other areas of computer science are based on depth first search in implicitty defined trees. For these algorithms a load-balancing scheme is required, which is able to evenly distribute parts of an irregularly shaped tree over the workstations with minimal interprocessor communication and without prior knowledge of the tree’s shape. For the (ARR) algorithm only minimal interprocessor communication is needed when necessary and it runs under the MPI (Message 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 computation dynamic load balancing performance metrics

Comparative assessment of agricultural technology generating practices in universities and research institutes in north central zone of Nigeria

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Information Processing in Agriculture 2017年第2期4卷 161-167页

作者： Gbolagade Benjamin Adesiji mohammed ibrahim Sola Emmanuel Komolafe Department of Agricultural Extension and Rural Development University of IlorinP.M.B.1515IlorinKwara StateNigeria Department of Agricultural Economics and Extension Technology Federal University of TechnologyMinnaNiger StateNigeria

To understand the technology generating practices among universities and research institutes in north central zone of Nigeria,this study examined sources of funds for technology generating activities,compared agro-technology generating practices and identified constraining factors hindering technology generating *** hundred and fifty-two academic staff were randomly selected from universities and one hundred and thirty-six respondents were drawn from research *** questionnaires with reliability coefficient of r=0.92 were used to elicit *** were analyzed using descriptive statistics,Likert-scale,T-test and Factor ***(93.4%)of universities’respondents used their personal funds to generate new technology compared to their counterparts in research *** most widely employed mechanism for generating agricultural technologies was joint radio programmes(mean=3.38)while the least was biotechnology(mean=2.57).Major areas of differences in technology generation between the two institutions were the physical distance(t=13.54;P<0.05),farmers participation in field research trials(t=8.50;P<0.05),farmers co-finance of adaptive research trials(t=3.77;P<0.05)and adequate research facilities and incentives to workers(t=2.05;P<0.05).Factors constraining technology generation for universities were poor access to knowledge and information on new innovation(r=0.815)while for research institutes it was limited physical resources(ICT,Telephone)(r=0.801).It was recommended therefore that respondents should look into options of writing alternate fund proposals and submitting to a wider range of funding *** of innovation could be strengthened through the formation of a formal technological linkage advisory council.

关键词： Technology Constraining factor Linkage practice Funding sources

Synthesis of activated carbon from spent tea leaves for aspirin removal

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1003-1011页

作者： Syieluing Wong Yowjeng Lee Norzita Ngadi ibrahim mohammed Inuwa Nurul Balqis Mohamed Department of Chemical Engineering Faculty of Chemical and Energy Engineering Universiti Teknologi Malaysia Malaysia Department of Industrial Chemistry Kaduna State University Kaduna Nigeria

Adsorption capacity of activated carbon prepared from spent tea leaves （STL-AC） for the removal of aspirin from aqueous solution was investigated in this study. Preliminary studies have shown that treatment with phosphoric acid （H3PO4） increased removal efficiency of STL-AC. Characterizations on STL-AC revealed excellent textural properties （1200 m2.g-1, 51% mesoporosity）, as well as distinctive surface chemistry （1.08 mmol.g-1 and 0.54 mmol.g-1 for acidic and basic oxygenated groups, pHpzc = 2.02）. Maximum removal efficiency of aspirin observed was 94.28% after 60 rain when the initial concentration was 100 mg.L-1, 0.5 g of adsorbent used, pH 3 and at a temperature of 30 ℃. The adsorption data were well fitted to the Freundlich isotherm model and obeyed the pseudo-second order kinetics model. The adsorption of aspirin onto STL-AC was exothermic in nature （△H = - 13.808 ***-1） and had a negative entropy change, △S （-41.444 ***-1）. A negative Gibbs free energy, △G was obtained indicating feasibility and spontaneity of the adsorption process. The adsorp- tion capacity of △C-STL （178.57 mg.g-1） is considerably high compared to most adsorbents synthesized from various sources, due to the well-defined textural properties coupled with surface chemistry of STL-AC which fa- vors aspirin adsorption. The results demonstrate the potential of STL-AC as aspirin adsorbent.

关键词： Activated carbon Spent tea leaves Aspirin Adsorption Kinetics Isotherm

Applying Swarm Intelligence Algorithms in Wireless Sensor Networks Energy Optimization

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Applying Swarm Intelligence Algorithms in Wireless Sensor Ne...

作者： Esraa mohammed mohammed ibrahim 湖南大学

学位级别：硕士

无线传感器网络(WSNs)是目前新兴技术之一。这是因为其在环境监测,结构监测,医疗保健和灾害管理方面的潜在应用。目前,研究人员所面临的突出挑战之一就是无线传感器网络的寿命。近年来,无线传感器网络得到了世界范围内的广泛关注,首先... 详细信息

无线传感器网络(WSNs)是目前新兴技术之一。这是因为其在环境监测,结构监测,医疗保健和灾害管理方面的潜在应用。目前,研究人员所面临的突出挑战之一就是无线传感器网络的寿命。近年来,无线传感器网络得到了世界范围内的广泛关注,首先从微电子机械系统技术(MEMS)得到了关注。微电子机械系统技术促进了小型传感器的发展,而这些传感器很小,并且它们的处理资源和计算资源都是有限的。传感器网络是一种无线自组织网络,在这个网络中,各个传感器独自地收集、处理物理环境中的数据,并且同外部基站进行数据交流。无线传感器网络由大量传感器节点组成,这些节点通过无线的方式相互通信它们的电量供应有限,由一个或者多个传感器、一个处理器、内存、电池、一个收音机和执行器组成。目前,许多可行的应用已经被提出来,例如：工业传感器网络、火山监控网络、生态监控网络等等。在无线传感器网络中,集群是通过在簇头进行数据汇总以进行能源管理的技术之一。通过集群方式降低了通信开销,减少传感器节点之间的接口,从而降低能源消耗。因为其网络可扩展性,节能特性和网络拓扑稳定的特点而广泛使用于无线传感器网络中。无线传感器的聚类技术是一种通过在类头中进行数据聚合而对能力进行高效管理的技术,聚类减少了通信的管理,即减少了能量的消耗。无线传感器网络之所以采用这种技术是因为网络的可扩展性、节能的属性和网络拓扑结构的稳定性。在这种技术中,传感器节点被聚类成了若干个不相交的集合,各个集合通过一个类头进行管理,这个类头也属于这个集合。集合中的成员把它们收集到的数据发送给它们的类头,而这些类头又把数据传给外部基站,这种技术对节省网络的能量很有帮助,因此应该努力地提高聚类网络的处理能力,而优化方法就是一种能延长网络使用寿命的技术。群智能算法是一种基于分散的自组织系统群聚行为的一种人工智能算法,由Gerardo Beni和Jing Wang于1989年提出。很久以前人们就发现了许多有趣的昆虫或动物行为,例如蚂蚁觅食、鸟群觅食等等,这些行为被称作群体行为。群智能系统一般由一些简单的agent组成,这些agents遵循很少的一些规则,开且系统没有控制中心。有名的群智能算法包括蚁群算法,鸟群算法等。无线传感器网络的聚类经常被公式化为一个优化问题,所以这篇文章提出了一种新的粒子群智能算法(IMOL),用于延长聚类无线传感器网络的使用寿命。IMOL是MOL的改进,而MOL是由PSO算法简化而来。在IMOL中,cosine法则被用来控制权重,它逐步地非线性地减小权重。通过对权重的控制,算法的全家搜索能力得到了提高。IMOL使得网络的聚类距离达到最小而且使得类头的分布得到了理想的优化。从实验结果可以看出,在种群大小和迭代次数都相同的情况下,IMOL比PSO收敛更快并且能搜索到更优的全局最优解。不仅如此,比起PSO、K-means、LEACH和LEACH-C这些算法,IMOL更能延长传感器网络的使用寿命并且传递给外部基站更多的数据。结果也证明,比起K-means算法,IMOL和PSO使得无线传感器网络的聚类更加理想。综上所述,使用IMOL的以聚类为基础的协议有更高的效率而且能够网络的使用寿命更长。

关键词：无线传感器网络集群算法群体智能技术

Is political business cycle an enemy to human development?Empirical evidence from Africa

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Economic and Political Studies 2019年第3期7卷 337-351页

作者： Abdul Ganiyu Iddrisu Jabir ibrahim mohammed Department of Economics University of GhanaLegonGhana Business School University of GhanaLegonGhana

Extant literature has argued that,with major extension of democracy since the 1990s,political business cycle has become more intense and has made African political systems more *** light of this,this paper examines both the existence of African political business cycles and their impact on human *** confirms the existence of political business cycles in *** of a panel fixed effects and system-GMM regression techniques for 38 African countries from 1990 to 2015 also suggest that such cycles worsen human development in African *** finding is consistent if we limit our analysis to various sub-regions of Africa,and also at two different income levels.

关键词： Political business cycle human development Africa

Secure Communication Scheme based on A New Hyperchaotic System

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Computers, Materials & Continua 2022年第10期73卷 1019-1035页

作者： Khaled Benkouider Aceng Sambas ibrahim mohammed Sulaiman Mustafa Mamat Kottakkaran Sooppy Nisar Non Destructive Testing Laboratory Automatic DepartmentJijel UniversityBP.9818000JijelAlgeria Department of Mechanical Engineering Universitas Muhammadiyah TasikmalayaTasikmalayaWest Java46196Indonesia School of Quantitative Sciences College of Art and SciencesUniversiti Utara MalaysiaSintok06010KedahMalaysia Faculty of Informatics and Computing Universiti Sultan Zainal AbidinBesut Campus22200Kuala BesutTerengganuMalaysia Department of Mathematics College of Arts and SciencesPrince Sattam bin Abdulaziz UniversityWadi Aldawaser11991Saudi Arabia

This study introduces a new continuous time differential system,which contains ten terms with three quadratic *** new system can demonstrate hyperchaotic,chaotic,quasi-periodic,and periodic behaviors for its different parameter *** theoretical and numerical analysis are investigated to confirm the complex hyperchaotic behavior of our proposed model using many tools that include Kaplan-Yorke dimension,equilibrium points stability,bifurcation diagrams,and Lyapunov *** means of Multisim software,the authors also designed an electronic circuit to confirm our proposed systems’physical *** and Multisim simulation results excellently agree with each other,which validate the feasibility of our new ten terms hyperchaotic system and make it very desirable to use in different domains especially in chaotic-based ***,by employing the drive response synchronisation,we developed a secure communication strategy for the proposed *** from the proposed scheme show that the proposed approach was successful in completing the encryption and decryption procedure.

关键词： Hyperchaotic system synchronization circuit design secure communication system

Chemically Radiative MHD Flow of a Micropolar Nanofluid over a Stretching/ Shrinking Sheet with a Heat Source or Sink

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Fluid Dynamics & Materials Processing 2024年第2期20卷 257-274页

作者： Parakapali Roja Shaik mohammed ibrahim Thummala Sankar Reddy Giulio Lorenzini Department of Mathematics Annamacharya Institute of Technology and SciencesKadapa516126India Department of Engineering Mathematics College of EngineeringKoneru Lakshmaiah Education FoundationVaddeswaram522302India Department of Mathematics Annamacharya Institute of Technology and SciencesKadapa516003India Department of Engineering and Architecture University of ParmaParma43124Italy

This study examines the behavior of a micropolar nanoﬂuidﬂowing over a sheet in the presence of a transverse magneticﬁeld and thermal *** addition,chemical(ﬁrst-order homogeneous)reactions are taken into account.A similarity transformation is used to reduce the system of governing coupled non-linear partial differ-ential equations(PDEs),which account for the transport of mass,momentum,angular momentum,energy and species,to a set of non-linear ordinary differential equations(ODEs).The Runge-Kutta method along with shoot-ing method is used to solve *** impact of several parameters is *** is shown that the micro-rota-tional velocity of theﬂuid rises with the micropolar ***,the radiation parameter can have a remarkable inﬂuence on theﬂow and temperature proﬁles and on the angular momentum distribution.

关键词： Chemical(ﬁrst order homogeneous)reaction magnetohydrodynamics micropolar nanoﬂuid stretching/shrinking sheet heat source

Influence of Thermophoresis and Brownian Motion of Nanoparticles on Radiative Chemically-Reacting MHD Hiemenz Flow over a Nonlinear Stretching Sheet with Heat Generation

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Fluid Dynamics & Materials Processing 2023年第4期19卷 855-868页

作者： S.mohammed ibrahim P.Vijaya Kumar G.Lorenzini Department of Engineering Mathematics College of EngineeringKoneru Lakshmaiah Education FoundationVaddeswaramAndhra Pradesh522302India Department of Mathematics GITAM(Deemed to be University)VisakhapatnamAndhra Pradesh530045India Department of Industrial Engineering University of Parma-Parco Area Delle ScienzeParma43124Italy

In this study,a radiative MHD stagnation point flow over a nonlinear stretching sheet incorporating thermophoresis and Brownian motion is *** a similarity method to reshape the underlying Partial differential equations into a set of ordinary differential equations(ODEs),the implications of heat generation,and chemical reaction on the flow field are described in *** a Homotopy analysis method(HAM)is used to interpret the related *** is found that an increase in the magnetic and velocity exponent parameters can damp the fluid velocity,while thermophoresis and Brownian motion promote specific thermal *** results also demonstrate that as the Brownian motion parameter is increased,the concentration values become smaller.

关键词： Hiemenz flow MHD thermal radiation nonlinear stretching chemical reaction HAM