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Comparative Larvicidal Property of Leaf Extract of Chromolaena odorata L (Composidae) and Chlopyrifos (Organophosphorus Compound) on Simulium Larvae

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biomedical and Environmental Sciences 2007年第4期20卷 313-316页

作者： b.m.m.TUR b.J.DAVOU University of Abuja Department of Biological Sciences P.M.B117AbujaNigeria

To assess the phytochemical properties of Chromoleana odorata in the control of blackflies to help check the problem of environmental pollution from the use of chemical insecticides. methods Dried pulverized leaves of Chromolaena odorata （100 g） were soaked in distilled water for 24 hours and the extract was filtered, marc pressed and evaporated over water bath. Stock solution of the dried mass （1 g） was concentrated by dissolving in 100 mL of water. Serial dilutions （100 mg/mL, 10 mg/mL, 1 mg/mL, 0.1 mg/mL, 0.01 mg/L, and 0.001 mg/mL） of both the extract and Chlopyrifos （organo phosphorus） were prepared and toxicity was tested on the larvae of Simulium species. Results The chemical compound recorded 100% larval mortality at all concentrations while the plant extract recorded 100% larval mortality in three （100, 10, and 1 mg/mL） of its diluent concentration. The percentage of larval mortality by chemical compound and plant extract was statistically insignificant （t = 0.2456, P〉0.05）, but the mortality rate was significant within 30 rain interval of exposure time （t= 3.756, P〈0.05）. The LCs0 of the plant extract was determined at about 0.001 mg/mL concentration. This showed that the plant extract had an appreciable larvicidal property close to that of the chemical compound. Conclusion This result indicates the usefulness of plant materials in the control of obnoxious insect vectors of mn. It also opens additional approach to the management of environment from toxic chemicals that are non-biodegradable and cause environmental imbalance in the ecosystem.

关键词： Chromolaena odorata Chlopyrifos Larvicidal property Simulium species

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Hybrid reinforced thermoset polymer composite in energy absorption tube application:A review

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Defence Technology（防务技术） 2018年第4期14卷 291-305页

作者： A.b.m.Supian S.m.Sapuan m.Y.m.Zuhri E.S.Zainudin H.H.Ya Department of mechanical and manufacturing Engineering Universiti Putra Malaysia Laboratory of bio Composite Technology Institute of Tropical Forestry and Research Products (INTROP)Universiti Putra Malaysia Department of mechanical Engineering Universiti Teknologi Petronas

The custom of hybridization fibre composite in energy absorption tube application has gained the attention of structural crashworthiness in composite material industry. Thus, the approach of this review is to understand the effect in hybridization within metal/synthetic fibre composite, synthetic/synthetic fibre composite and nature/synthetic fibre composite as energy absorption tube, which reflects on the energy absorption characteristics and crashworthiness behaviors in previous the study. by way of instance, a wide range of methodology and particular parameter in previous study such as the effect in fibre arrangement, matrix polymer, technique of fabrication, fibre treatment(natural fibre), design in geometry/cross-section and others mechanism of hybrid fibre composite tube are highlighted which to comprehend the capability of the mechanical performance and collapsible behavior as sacrificial structure in high-performance structure applications. moreover, in the recently studies there have been many of the research regarding structural materials as energy absorption tube has been introduced such as metal/matrix composites, new alloy metals and polymer composites which intended to evaluate the performance of these materials into circumstance in loading and impact characteristic. Therefore, this review article is trying to explore the research articles related to the effect of hybridization fibres and thermoset polymer as reinforcement for energy absorption tube research and expected would provide an information and idea which to expend the knowledge in future study of hybridization effect for energy absorption tube, moreover the development for future potential as new hybrid composite fibre materials from the natural/synthetic fibres reinforced composite material in employing of high-performance energy absorption tube application is still less discover and highlighted.

关键词： Energy absorption tube Hybrid composites Collapse behavior Crashworthiness

Conceptual design of irradiation device for silicon neutron transmutation doping around Es-Salam research reactor

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Nuclear Science and Techniques 2020年第4期31卷 69-78页

作者： m.Salhi b.mohammedi S.Laouar m.Dougdag m.Touiza m.Abbaci m.moughari Centre de Recherche Nucle′aire de birine 17200 Ain OusseraAlgeria Institut Alge′rien de formation en Ge′nie Nucle′aire 16050 DrariaAlgerAlge′rie

Silicon neutron transmutation doping remains one of the most viable nuclear applications for research *** this kind of product involves an irradiation method capable of fulfilling the quality requirements of doping and alleviating the challenges related to the design and safety of the irradiation *** this paper,we propose an irradiation device prototype for neutron transmutation doping of silicon ingots with diameters of 2 to 3 *** on the Es-Salam research *** thermal hydraulic analysis of the proposed irradiation device was performed to determine the optimum conditions for *** effect of the mechanical vibrations induced by the circulation of coolant in the device was quantified via experimental measurements under different flow *** results show that the maximum temperature reached by the silicon ingots is below the temperature limit,effectively validating the design of the irradiation *** investigations are prospected to further optimize the design and the irradiation *** irradiation of silicon ingots with a large diameter will be considered.

关键词： Irradiation device prototype Es-Salam research reactor NTD-Si Irradiation temperature CFD method

User scheduling and power allocation for downlink multi-cell multi-carrier NOmA systems

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Digital Communications and Networks 2023年第1期9卷 252-263页

作者： Abuzar b.m.Adam Xiaoyu Wan Zhengqiang Wang School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

In Non-Orthogonal multiple Access(NOmA),the best way to fully exploit the benefits of the system is the efficient resource *** the NOmA power domain,the allocation of power and spectrum require solving the mixed-integer nonlinear programming NP-hard *** this paper,we investigate user scheduling and power allocation in multi-Cell multi-Carrier NOmA(mCmC-NOmA)*** achieve that,we consider Weighted Sum Rate maximization(WSRm)and Weighted Sum Energy Efficiency maximization(WSEEm)***,we tackle the problem of user scheduling for fixed power using Fractional Programming(FP),the Lagrange dual method,and the decomposition ***,we consider Successive Pseudo-Convex Approximation(SPCA)to deal with the WSRm ***,for the WSEEm problem,SPCA is utilized to convert the problem into separable scalar problems,which can be parallelly ***,the Dinkelbach algorithm and constraints relaxation are used to characterize the closed-form solution for power *** simulations have been implemented to show the efficiency of the proposed framework and its superiority over other existing schemes.

关键词： Weighted sum rate Weighted energy efficiency Non-orthogonal multiple access Successive pseudo-convex approximation Fractional programming

Tie-line Power Flow Control method for Gridconnected microgrids with SmES based on Optimization and Fuzzy Logic

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Journal of modern Power Systems and Clean Energy 2020年第5期8卷 941-950页

作者： Sayed m.Said Abdelfatah Ali bálint Hartmann Department of Electrical Engineering Aswan University81542 AswanEgypt Department of Electric Power Engineering Budapest University of Technology and Economics1111 BudapestHungary Department of Electrical Engineering South Valley University83523 QenaEgypt

In an active distribution grid,renewable energy sources(RESs)such as photovoltaic(PV)and energy storage systems(e.g.,superconducting magnetic energy storage(SmES))can be combined with consumers to compose a microgrid(mG).The high penetration of PV causes high fluctuations of tie-line power flow and highly affects power system *** can lead to several technical problems such as voltage fluctuations and excessive power *** this paper,a fuzzy logic control based SmES method(FSm)and an optimized fuzzy logic control based SmES method(OFSm)are proposed for minimizing the tie-line power ***,the fluctuations and transmission power losses are *** FSm,SmES is used with a robust fuzzy logic controller(FLC)for controlling the tie-line power *** optimization model is employed in OFSm to simultaneously optimize the input parameters of the FLC and the reactive power of the voltage source converter(VSC)of *** objective function of minimizing the tieline power flow is incorporated into the optimization *** swarm optimization(PSO)algorithm is utilized to solve the optimization problem while the constraints of the utility power grid,VSC,and SmES are *** simulation results demonstrate the effectiveness and robustness of the proposed methods.

关键词： Utility power grid microgrid photovoltaic(PV) superconducting magnetic energy storage(SmES) tie-line power fuzzy logic control(FLC)

Suboptimal Auditory Dominance in Audiovisual Integration of Temporal Cues

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Tsinghua Science and Technology 2011年第2期16卷 121-132页

作者： m maiworm b Rder biological Psychology and Neuropsychology University of Hamburg

The present study examined whether audiovisual integration of temporal stimulus features in humans can be predicted by the maximum likelihood estimation （mLE） model which is based on the weighting of unisensory cues by their relative reliabilities. In an audiovisual temporal order judgment paradigm, the reliability of the auditory signal was manipulated by Gaussian volume envelopes, introducing varying degrees of temporal uncertainty. While statistically optimal weighting according to the mLE rule was found in half of the participants, the other half consistently overweighted the auditory signal. The results are discussed in terms of a general auditory bias in time perception, interindividual differences, as well as in terms of the conditions and limits of statistically optimal multisensory integration.

关键词： audiovisual integration statistically optimal behavior temporal perception

Structural, elastic and electronic properties for m_2 XC (m=Ti and Cr, X=Ga and Al) phases from ab initio calculations

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Acta metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： b. Ghebouli m.A. Ghebouli m. Fatmi N. bouarissa m. benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids materials Department of Physics Faculty of Science University of Setif Department of Physics University Center Research Unit on Emerging materials Ferhat Abbas University of Setif Department of Physics Faculty of Sciences King Khalid University Central metallurgical Research and Development Institute P.O. box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m2XC phases depending on the type of m transition metal （m are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave approach in both the local density and generalized gradient approximations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, Debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m elements on the machinability indices of the material have been examined. The electronic properties have been discussed in terms of chemical bonding showing that bonding is due to md-Cp and md-Xp hybridizations. m-C bonds are stiffer than m-X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m-X and m-C bonds increases with increasing the number of VEC.

关键词： m2XC phases ab initio Pressure effect band structures

multidimensional modeling of the stenosed carotid artery: A novel CAD approach accompanied by an extensive lumped model

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Acta mechanica Sinica 2014年第2期30卷 259-273页

作者： A.Kashefi m.mahdinia b.Firoozabadi m.Amirkhosravi G.Ahmadi m.S.Saidi Department of mechanical Engineering Sharif University of Technology Department of mechanical Engineering University of California Berkeley Faculty of Engineering Department of Mechanical EngineeringSharif University of Technology Faculty of Engineering Department of Mechanical and Aeronautical EngineeringClarkson University

This study describes a multidimensional 3D/lumped parameter（LP） model which contains appropriate inflow/outflow boundary conditions in order to model the entire human arterial trees. A new extensive LP model of the entire arterial network（48 arteries） was developed including the effect of vessel diameter tapering and the parameterization of resistance, conductor and inductor variables. A computer aided-design（CAD） algorithm was proposed to effciently handle the coupling of two or more 3D models with the LP model, and substantially lessen the coupling processing time. Realistic boundary conditions and Navier-Stokes equations in healthy and stenosed models of carotid artery bifurcation（CAb） were used to investigate the unsteady Newtonian blood flow velocity distribution in the internal carotid artery（ICA）. The present simulation results agree well with previous experimental and numerical studies. The outcomes of a pure LP model and those of the coupled 3D healthy model were found to be nearly the same in both cases. Concerning the various analyzed 3D zones, the stenosis growth in the ICA was not found as a crucial factor in determining the absorbing boundary *** paper demonstrates the advantages of coupling local and systemic models to comprehend physiological diseases of the cardiovascular system.

关键词： Hemodynamic 3D/LP coupling CAD Realis-tic boundary conditions Carotid artery bifurcation Stenosis