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Conversion of an atomic to a molecular argon ion and low pressure argon relaxation

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Chinese Physics B 2016年第1期25卷 697-705页

作者： m n Stankov A P Jovanovie V Lj markovic S n Stamenkovic Department of Physics Faculty of Sciences and MathematicsUniversity of Ni Viegradska 33Ni 18001Serbia

The dominant process in relaxation of DC glow discharge between two plane parallel electrodes in argon at pressure 200 Pa is analyzed by measuring the breakdown time delay and by analytical and n.m.rical models. By using the approx- imate analytical model it is found that the relaxation in a range from 20 to 60 ms in afterglow is dominated by Ar＋ ions, produced by atomic-to-molecular conversion of Ar＋ ions in the first several milliseconds after the cessation of the discharge. This conversion is confirmed by the presence of double-Gaussian distribution for the formative time delay, as well as con- version.m.xima in a set of memory curves measured in different conditions. Finally, the n.m.rical one-dimensional （1D） model for determining the n.m.er densities of dominant particles in stationary DC glow discharge and two-dimensional （2D） model for the relaxation are used to confirm the previous assumptions and to determine the corresponding collision and transport coefficients of dominant species and processes.

关键词： argon discharge afterglow relaxation fluid model plasma reactions

Computational Film Cooling Effectiveness of Dual Trench Configuration on Flat Plate at moderate Blowing Ratios

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Journal of marine Science and Application 2013年第2期12卷 208-218页

作者： Antar m.m. Abdala Qun Zheng Fifi n.m. Elwekeel Ping Dong Power and Energy Engineering Harbin Engineering University Harbin 150001 China

In the present work, computational simulations was made using AnSYS CFX to predict the improvements in film cooling performance with dual trench. Dual-trench confguradon consists of two trenches together, one wider trench and the other is narrow trench that extruded from the wider one. Several blowing ratios in the range （0.5：5） were investigated. The pitch-to-diameter ratio of 2.775 is used. By using the dual trench configuration, the coolant jet impacted the trench wall two times allowing increasing the spreading of coolant laterally in the trench, reducing jet velocity and jet completely covered on the surface. The results indicate that this configuration increased adiabatic effectiveness as blowing ratio increased. The spatially averaged adiabatic effectiveness reached 57.6% for at m= 2. no observed film blow-off at all blowing ratios. The adiabatic film effectiveness of dual trench case outperformed the narrow trench case, laidback fan-shaped hole, fan-shaped hole and cylinder hole at different blowing ratios.

关键词： gas turbine dual-trench film cooling adiabatic effectiveness jet interaction phen.m.na flat plate moderate blowing ratios

Insights from an academic endeavor into central nervous system drug discovery

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neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An.m.Voets Tim Vanmierlo Rudy Schreiber BIOmED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University mS Center(UmSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in.m.dern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(mazzucato,2013).

关键词： academic approval consequences

Lattice thermal conduction in cadmium arsenide

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Chinese Physics B 2022年第11期31卷 424-430页

作者： R F Chinnappagoudra m D Kamatagi n R Patil n S Sankeshwar Department of Physics S.S.Government First Grade CollegeNargund-582207KarnatakaIndia Research Resource Centre Visvesvaraya Technological UniversityBelagavi-590018KarnatakIndia Department of Physics B V B College of Engineering and TechnologyHubliKarnataka 80031India Department of Physics&Electronics CHRIST(Deemed to be University)Bangalore-560029KarnatakaIndia

Lattice thermal conductivity(LTC)of cadmium arsenide(Cd_(3)As_(2))is studied over a wide temperature range(1–400 K)by employing the Callaway *** acoustic phonons are considered to be the major carriers of heat and to be scattered by the sample boundaries,disorder,impurities,and other phonons via both Umklapp and normal phonon *** calculations of LTC of Cd_(3)As_(2)bring out the relative importance of the scattering *** systematic analysis of recent experimental data on thermal conductivity(TC)of Cd_(3)As_(2)samples of different groups,presented in terms of LTC,κL,using a nonlinear regression.m.thod,reveals good fits to the TC data of the samples considered for Tnd suggests a value of 0.2 for the Gruneisen *** is,however,found that for T>100 K the inclusion of the electronic component of TC,κe,incorporating contributions from relevant electron scattering mechanisms,is needed to obtain good agreement with the TC data over the wide temperature *** detailed investigations of TC of Cd_(3)As_(2)are required to better understand its suitability in thermoelectric and thermal management devices.

关键词： dirac semimetals Cd_(3)As_(2) thermal conductivity phonon scattering

A FLEXIBLE OBJECTIVE-COnSTRAInT APPROACH AnD A nEW ALGORITHm FOR COnSTRUCTInG THE PARETO FROnT OF mULTIOBJECTIVE OPTImIZATIOn PROBLEmS

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Acta mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR m.GHAZnAVI Faculty of mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given.m.ltiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Solar Radiation and Temperature measurement of Solar Dish Concentrator System

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Journal of Energy and Power Engineering 2010年第2期4卷 15-19页

作者： Y. Rafeeu m.Z.A.A. Kadir S.m. Abdulla n.m. Adam Department of Electrical and Electronic Engineering Universiti Putra Malaysia Serdang 43400 Malaysia Department of mechanical and manufacturing Engineering Universiti Putra Malaysia Serdang 43400 Malaysia

Concentrating solar power （CSP） technologies could be one of the major contributor to worlds future energy needs and which would be cheap and clean sources of energy. This would improve energy utilization, higher conversion efficiency with reliable and affordable supply of electricity to the public. The proposed approach is using 18 inch diameter of solar dish concentrator to measure the solar radiation using the aluminium foil as a reflector. In this paper, solar radiation is collected to investigate the solar fraction on incoming solar energy in wet climate.

关键词： Concentrating solar power solar energy olar fraction.

Weathering reflected by the chemical composition of alluvial soils from the Zeya and Selemdzha river valleys

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Science China Earth Sciences 2018年第5期61卷 604-613页

作者： O.A.SOROKInA m.n.GYSEV Institute of Geology and nature management Far East Branch Russian Academy of Sciences

The paper examines the chemical composition of alluvial soils from the Zeya and Selemdzha River valleys, one of the branch rivers in the Amur River basin. It has been established that the compositions of these soils are characterized by a relative shortage of practically all analyzed macro-and microelements as compared with UCC(upper continental crust) and PAAS(postArhean Australian average shale) compositions. The chemical composition of alluvial soils approximates that of the soils in nE China and Korea due to similar climatic and geographic conditions. On the basis of relationships between.m.jor and trace elements and peculiarities of trace elements concentration it is shown that the alluvial soils in the middle reaches of the Zeya River were formed by the sources largely transformed by chemical weathering processes. By comparison, the soils in the Selemdzha River and lower reaches of the Zeya River(below the Selemdzha River mouth) are dominated by material to a large degree reworked by the physical processes rather than chemical ones. This inference conforms with specific geological settings of the water-collector.

关键词： Alluvial soils Weathering indices Amur Zeya

Three-dimensional free vibration analysis of multi-directional functionally graded piezoelectric annular plates on elastic foundations via state space based differential quadrature method

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Applied mathematics and mechanics(English Edition) 2015年第4期36卷 439-464页

作者： m.H.YAS n.m.LOUDI Department of mechanical Engineering Razi University

The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric （FGP） annular plate resting on two parameter （Pasternak） elastic foundations is investigated under different boundary conditions. The material properties are assumed to vary continuously along the radial and thickness directions and have exponent-law distribution. A semi-analytical approach n.m.d the state space based differential quadrature method （SSDQm） is used to provide an analytical solution along the thickness using the state space method （SSm） and an approximate solution along the radial direction using the one-dimensional differential quadrature method （DQm）. The influence of the Winkler and shear stiffness of the foundation~ the material property graded variations, and the circumferential wave n.m.er on the n.m.imensional natural frequency of multi-directional FGP annular plates is studied.

关键词： multi-directional functionally graded piezoelectric annular plate freevibration

Ameliorating the re/dehydrogenation behaviour of mgH2 by zinc titanate addition

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Journal of magnesium and Alloys 2023年第6期11卷 2205-2215页

作者： n.A.Ali n.A.Sazelee m.F.md Din.m.m.nasef A.A.Jalil Haizen Liu m.Ismail Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Electrical and Electronic Engineering Faculty of EngineeringNational Defence University of MalaysiaKem Sungai BesiKuala LumpurMalaysia Center of Hydrogen Energy Institute of Future EnergyUniversiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Department of Chemical and Environmental Engineering Malaysia Japan International Institute of TechnologyUniversiti Teknologi MalaysiaJalan Sultan Yahya PetraKuala Lumpur 54100Malaysia Faculty of Chemical and Energy Engineering Universiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Guangxi novel Battery materials Research Center of Engineering Technology State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key Laboratory of Featured metal materials and Life-cycle Safety for Composite Structures Nanning 530004China

magnesium hydride(mgH_(2))is the most feasible and effective solid-state hydrogen storage material,which has excellent reversibility but initiates decomposing at high temperatures and has slow kinetics ***,zinc titanate(Zn_(2)TiO_(4))synthesised by the solid-state method was used as an additive to lower the initial temperature for dehydrogenation and enhance the re/dehydrogenation behaviour of mgH_(2).With the presence of Zn_(2)TiO_(4),the starting temperature for the dehydrogenation of mgH_(2)was remarkably lowered to around 290℃–305℃.In addition,within 300 s,the mgH_(2)–Zn_(2)TiO_(4)sample absorbed 5.0 wt.%of H_(2)and 2.2–3.6 wt.%H_(2)was liberated from the composite sample in 30 min,which is faster by 22–36 times than as-milled mgH_(2).The activation energy of the mgH_(2)for the dehydrogenation process was also downshifted to 105.5 k J/mol with the addition of Zn_(2)TiO_(4)indicating a decrease of 22%than as-milled mgH_(2).The superior behaviour of mgH_(2)was due to the formation of mg Zn_(2),mgO and mgTiO_(3),which are responsible for ameliorating the re/dehydrogenation behaviour of mgH_(2).These findings provide a new understanding of the hydrogen storage behaviour of the catalysed-mgH_(2)system.

关键词： Hydrogen storage Solid-state storage mgH_(2) Additive Zn_(2)TiO_(4)