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Analytical study of Cattaneo–Christov heat flux model for a boundary layer flow of Oldroyd-B fluid

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Chinese Physics B 2016年第1期25卷 657-662页

作者： F m Abbasi m mustafa S A Shehzad m S Alhuthali t Hayat Department of mathematics Comsats Institute of lnformaHon TechnologyIslamabad 44000Pakistan School of Natural Sciences(SNS) National University of Science and Technology(NUST)Islamabad 44000Pakistan Department of mathematics Comsats Institute of/nformation TechnologySahiwa157000Pakistan NAAm Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan

We investigate the Cattaneo-Christov heat flux model for a two-dimensional laminar boundary layer flow of an incompressible Oldroyd-B fluid over a linearly stretching sheet. mathematical formulation of the boundary layer problems is given. the nonlinear partial differential equations are converted into the ordinary differential equations using similarity transformatioris. the dimensionless velocity and temperature profiles are obtained through optimal homotopy analysis method （OHAm）. the influences of the physical parameters on the velocity and the temperature are pointed out. the results show that the temperature and the thermal boundary layer thickness are smaller in the Cattaneo-Christov heat flux model than those in the Fourier＇s law of heat conduction.

关键词： Oldroyd-B fluid Cattaneo-Christov heat flux nonlinear analysis

Schwarzschild microscopes in vacuum ultraviolet and soft X-ray regions

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Nuclear Science and techniques 2005年第3期16卷 129-138页

作者： m.WAtANABE m.YANAGIHARA t.EJImA m.tOYODA Y.KONDO t.HAtANO t.tSURU m.YAmAmOtO Institute of multidisciplinary Research for Advanced materials Tohoku University2-1-1 KatahiraAobakuSendai 980-8577Japan

microscopes in vacuum ultraviolet and soft X-ray regions using a normal incidence type of Schwarzschild objective are reviewed. the objective consists of a concave mirror and a convex mirror coated with a high reflectance multilayer,having a large numerical aperture comparing with other objectives. the microscopes have been used to diagnose inertia-confinement-fusion plasmas,and to investigate small samples or microstructures of in- organic and organic materials by imaging them using laboratory light sources. Synchrotron radiation has been also used to obtain a microbeam for a photoelectron scanning microscope with a spatial resolution of 0.1 μm. the struc- ture and performance of two laboratory microscopes developed at tohoku University are demonstrated. One of them is a soft X-ray emission imaging microscope. An image of an artificial pattern made of W and SiO2 on Si wafer by focusing Si L emission was presented. the other is an ultraviolet photoelectron scanning microscope using a He (he- lium) gas discharge lamp. the valence band spectra of a microcrystal of FeWO4 were presented. Furthermore other applications such as demagnifying optics for lithography and optics to gather fluorescence for emission spectroscopy are introduced.

关键词：施瓦兹希尔物镜真空紫外线辐射软X-射线显微镜光电子

Evolution of plant reproduction:From fusion and dispersal to interaction and communication

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Chinese Science Bulletin 2009年第14期54卷 2390-2403页

作者： WILLEmSE michiel t m Laboratory of Plant Cytology and morphology Wageningen University6717LM EdeThe Netherlands

Based on the existing data concerning the evolution of the sexual reproduction, it is argued that the processes of sex differentiation and interactions play a key role in evolution. From the beginning environment and organism are unified. In a changing dynamic environment life originates and the interaction between life and environment develops from simple to more complex organisms. Sexual reproduction is introduced after the origin of meiosis and is a key process in evolution. the asexual reproduction process prepares to dispersal. Sexual reproduction process adds the genome renewal and the gamete-gamete interaction. Reproduction and dispersal are connected and the process of reproduction has similarities between asexual and sexual reproduction. Unicellular algae develop the physiological and morphological sex differentiation. Sex differentiation is connected with the way of dispersal. the step to multicellular plants introduces cell isolation after meiosis and by the stay on the mother plant within a cell or organ, plant-cell apoplastic interaction originates and by prolonged stay the plant-plant interaction. this stay influences the type of dispersal. A life cycle with alternation of generations and two moments of dispersal permits plants to go on land. In ferns a shift in the moment of sex differentiation to meiospore happens and the stay of the macrospore leads to the seed plants. In water all types of sexual reproduction, interactions and the alternation of generations are prepared and these are used to conquest land. On land the biotic dispersal is realized. the phylogeny of sexual reproduction reveals that the sex differentiation and interaction are the main causes in the evolution of sexual reproduction. Sexual reproduction shows interactions during gamete fusion, between organism and environment and in multicellular plants between organisms. With respect to other types of interaction as in symbiosis or the nutrient chain, interaction is considered as an im

关键词：基因组蕨类植物植物细胞有性生殖

Optimization of Cu content for the development of high-performance t5-treated thixo-cast Al-7Si-0.5mg-Cu(wt.%)alloy

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Journal of materials Science & technology 2021年第34期93卷 178-190页

作者： K.Yamamoto m.takahashi Y.Kamikubo Y.Sugiura S.Iwasawa t.Nakata S.Kamado Nagaoka University of technology NagaokaJapan Asanuma Giken Co. Ltd.HamamatsuJapa Industrial Research Institute of Shizuoka Prefecture ShizuokaJapan

Cu content has been successfully optimized in a thixo-cast and directly aged(t5-treatment)Al-7 Si-0.5 mg(wt.%)*** after the 0.5%Cu addition,plate-like Al_(2)Cu(θ’)phases,which contribute to high strengths and large plasticity,are *** formation of a large fraction of Cu-containing brittle phases could be suppressed as ***,the Al-7Si-0.5mg-0.5Cu alloy exhibits high ultimate tensile strength,0.2%proof stress,and elongation to failure of 296 mPa,209 mPa,and 8.8%,*** results in a high quality index similar to that of solution-treated and subsequently aged(t6-treated)Al-7 Si-mg alloys.A Cu addition over 1.0%further improves the strengths;however,this leads to poor ductility because of the high fraction of Cu-containing brittle phases.

关键词： Al-Si-mg-Cu alloy thixo-casting t5-treatment mechanical property microstructure

Quantal studies of sodium 3p ← 3s photoabsorption spectra perturbed by ground lithium atoms

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Chinese Physics B 2019年第6期28卷 146-154页

作者： N Lamoudi F talbi m t Bouazza m Bouledroua K Alioua Badji mokhtar University B.P.12 AnnabaAlgeria Laboratoire LESImS Laboratoire de Physique des Rayonnements Laboratoire LAmA Souk-Ahras University Souk-Ahras 41000Algeria

the pressure broadening in the far wings, where the sodium Na(3 p ← 3 s) resonance line is perturbed by ground lithium Li(2 s) atoms, has been theoretically analyzed. the NaLi potential–energy curves and the transition dipole moments are constructed by using a reliable ab initio data points to carry out the reduced-absorption coefficients k_r(ν, t). this quantum-mechanical investigation have demonstrated that the NaLi profile spectra show a satellite future in the red wing at wavelength λ = 685 nm in the temperature range 4000 K–1.8 × 10~4 K. the computation could also exhibit a second satellite, in the blue wing, near the wavelength λ = 574 nm beyond 6000 K and a third peak located at λ = 490 nm which begins to appear at 1.8 × 10~4 K.

关键词： pressure broadening absorption coefficient satellite structure radiative lifetime

treating wastewater under zero waste principle using wetland mesocosms

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 155-168页

作者： Safaa m.Ezzat mohammed t.moustafa microbiology Deptartment Central Laboratory for Environmental Quality Monitoring(CLEQM)National Water Research Center(NWRC)CairoEgypt

the present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating *** system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence *** removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and *** bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste *** treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil *** zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).the harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive *** could certainly offset part of the operation and maintenance costs and optimize the system implementation *** the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.

关键词： Wastewater Dynamic roughing filter Cyperus papyrus(L.) Zeolite Zero waste

Oscillatory Couette flow of rotating Sisko fluid

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Applied mathematics and mechanics(English Edition) 2014年第10期35卷 1301-1310页

作者： t.HAYAt S.ABELmAN m.HAmESE Department of mathematics Quaid-i-Azam University Department of mathematics Faculty of Science King Abdulaziz University Centre for Differential Equations Continuum Mechanics and Applications School of Computational and Applied Mathematics University of the Witwatersrand

the oscillatory Couette flow of a magnetohydrodynamic （mHD） Sisko fluid between two infinite non-conducting parallel plates is explored in a rotating frame. the lower plate is fixed, and the upper plate is oscillating in its own plane. Using mAtLAB, a numerical solution to the resulting nonlinear system is presented. the influence of the physical parameters on the velocity components is analyzed. It is found that the effect of rotation on the primary velocity is more significant than that on the secondary velocity. Further, the oscillatory character in the flow is also induced by rotation. the considered flow situation behaves inertialess when the Reynolds number is small.

关键词： Couette flow Sisko fluid numerical solution oscillatory flow

An ab initio investigation of vibrational, thermodynamic, and optical properties of Sc_2AlC mAX compound

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Chinese Physics B 2016年第10期25卷 103-108页

作者： m A Ali m t Nasir m R Khatun A K m A Islam S H Naqib Department of Physics Chittagong University of Engineering and Technology Department of Arts & Sciences Bangladesh Army University of Science and Technology Department of Physics University of Rajshahi International Islamic University Chittagong

the structural vibrational, thermodynamical, and optical properties of potentially technologically important, weakly coupled mAX compound, Sc2 Al C are calculated using density functional theory(DFt). the structural properties of ScAlC are compared with the results reported earlier. the vibrational, thermodynamical, and optical properties are theoretically estimated for the first time. the phonon dispersion curve is calculated and the dynamical stability of this compound is investigated. the optical and acoustic modes are observed clearly. We calculate the Helmholtz free energy(F), internal energy(E), entropy(S), and specific heat capacity(Cv) from the phonon density of states. Various optical parameters are also calculated. the reflectance spectrum shows that this compound has the potential to be used as an efficient solar reflector.

关键词： mAX compound phonon dispersion thermodynamical properties optical properties

Reliability analysis of earth dams using direct coupling

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Journal of Rock mechanics and Geotechnical Engineering 2020年第2期12卷 366-380页

作者： A.t.Siacara G.F.Napa-García A.t.Beck m.m.Futai Department of civil engineering university of sao paulosao paulobrazil Research group geoinfrausp university of sao paulosao paulobrazil Instituto tecnológico vale ouro pretominas geraisbrazil

Numerical methods are helpful for understanding the behaviors of geotechnical ***,the computational cost sometimes may become prohibitive when structural reliability analysis is performed,due to repetitive calls to the deterministic *** this paper,we show how accurate and efficient reliability analyses of geotechnical installations can be performed by directly coupling geotechnical software with a reliability *** earth dam is used as the study object under different operating *** limit equilibrium method of morgenstern-Price is used to calculate factors of safety and find the critical slip *** conmercial software packages Seep/W and Slope/W are coupled with StRAnD structural reliability *** indices of critical probabilistic surfaces are evaluated by the first-and second-order structural reliability methods(FORm and SORm),as well as by importance sampling monte Carlo(ISmC)*** means of sensitivity analysis,the effective friction angle(φ′)is found to be the most relevant uncertain geotechnical parameter for dam *** correlations between different geotechnical properties are shown to be relevant in terms of equilibrium reliability ***,it is shown herein that a critical slip surface,identified in terms of the minimum factor of safety(FS),is not the critical surface in terms of the reliability index.

关键词： Earth dam Geotechnical parameters Reliability analysis Water level