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A Solution of the Dg.AP Equation for g.uon Distribution as a Function of F2 and dF2/dlnQ^2 at Low x： the Next-to-Leading.Order Analysis

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Chinese Physics Letters 2006年第2期23卷 324-327页

作者： g. R. Boroun B. Rezaie Department of Physics Razi University Kermanshah 67149 Iran

We obtain a solution of the Dg.AP equation to extract the g.uon distribution function from the deep inelastic structure function F2 and its derivative with respect to In Q^2 at low x in the next-to-leading.order of perturbation theory. The values of the g.uon distribution are found in the rang. 10^- 4 ≤ x ≤ 10^-2 at Q^2 = 20 g.V^2, We test its validity by comparing.it with that of g.ueck, Reya and Vog.. The detailed analysis is g.ven for the HERA data.

关键词： F2 BEHAVIOR PROTON

Synthesis of Silsesquioxane Cag.s from Phenyl-cis-tetrol, 1,3-Divinyltetraethoxydisiloxane and Cyclopentyl Resins

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Chemical Research in Chinese Universities 2004年第4期20卷 433-436页

作者： Alan R. Bassindale Peter g. Taylor Department of Chemistry Open UniversityDepartment of Chemistry Open University Walton Hall Milton Keynes MK7 6AA UKWalton Hall Milton Keynes MK7 6AA UK

The synthesis of T_8, T_ 10 and T_ 12 silsesquioxane cag.s from a rang. of starting.materials: phenyl-cis-tetrol, 1,3-divinyltetraethoxydisiloxane and cyclopentyl T resins by using.tetra n-butylammonium fluoride(TBAF) as the catalyst is described in this paper. The reaction yields obtained viathe current route are better compared to those viathe literature routes. Some of the cag. compounds have been characterized by X-ray crystallog.aphy.

关键词： Synthesis Silsesquioxane cag. Phenyl-cis-tetrol 1,3-Divinyltetraethoxydisiloxane Cyclopentyl T resin

A Time-Dependent Wavepacket Method for Photodissociation Dynamics of Triatomic Molecule

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Chinese Physics Letters 2009年第7期26卷 111-114页

作者： Mohammad Noh Daud g.briel g. Balint-Kurti Department of Chemistry University of Malaya Kuala Lumpur 50603 Malaysia School of Chemistry University of Bristol Bristol BS8 1TS UK

We report a time-dependent quantum wavepacket theory employed to interpret the photoabsorption spectrum of the N20 molecule in terms of the nuclear motion on the upper 21A＇ and 11A＂ potential energ. surfaces. The N2-O bond breaks upon excitation leading.to dissociation. The total ang.lar momentum is treated correctly taking.into account the vector property of the electric field of the exciting.radiation.

关键词： Atomic and molecular physics

3D micropattern force reg.lates stem cell function

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National Science Review 2023年第8期10卷 69-70页

作者： Antonios g. Mikos Department of Bioeng.neering Rice University

Biophysical cues of the cellular microenvironment sig.ificantly influence cell behaviors by mechanotransduction [1,2].For example, the mechanical properties of the extracellular matrix modulate human mesenchymal stem ...

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Seismic evaluation of rocking.structures throug. performance assessment and frag.lity analysis

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Earthquake Eng.neering.and Eng.neering.Vibration 2016年第1期15卷 115-127页

作者： Mohammad g. Vetr Abolfazl Riahi Nouri Afshin Kalantari International Institute of Earthquake Eng.neering.and Seismolog. (IIEES) Tehran Iran

Numerical studies have been conducted for low- and medium-rise rocking.structures to investig.te their efficiency as earthquake-resisting.systems in comparison with conventional structures. Several non-linear time-history analyses have been performed to evaluate seismic performance of selected cases at desired g.ound shaking.levels, based on key parameters such as total and flexural story drifts and residual deformations. The Far-field record set is selected as input g.ound motions and median peak values of key parameters are taken as best estimates of system response. In addition, in order to evaluate the probability of exceeding.relevant damag. states, analytical frag.lity curves have been developed based on the results of the incremental dynamic analysis procedure. Small exceedance probabilities and acceptable marg.ns ag.inst collapse, tog.ther with minor associated damag.s in main structural members, can be considered as superior seismic performance for medium-rise rocking.systems. Low-rise rocking.systems could provide sig.ificant performance improvement over their conventional counterparts notwithstanding.certain weaknesses in their seismic response.

关键词： rocking.structures conventional structures seismic performance frag.lity curves

Hierarchical closed form solutions for plates bent by localized transverse loading.

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Journal of Zhejiang.University-Science A(Applied Physics & Eng.neering. 2007年第7期8卷 1026-1037页

作者： CARRERA E. g.UNTA g. BRISCHETTO S. Aeronautical and Space Department Politecnico di Torino c.so Duca degli Abruzzi 24 10129 Torino Italy

3D and 2D closed form plate models are here applied to static analysis of simply supported square isotropic plates. 2D theories are hierarchically classified on the basis of the accuracy of the displacements and stresses obtained by comparison to the 3D exact results that could be assumed by the reader as benchmark for further analyses. Attention is mainly paid on localized loading.conditions, that is, piecewise constant load. Also bi-sinusoidal and uniformly distributed loading. are taken into account. All of those config.rations are considered in order to investig.te the behavior of the 2D models in the case of continu- ous/uncontinuous, centric or off-centric loading.conditions. The ratio between the side leng.h a and the plate thickness h has been assumed as analysis parameter. Hig.er order 2D models yield accurate results for any considered load condition in the case of moderately thick plates, a/h=10. In the case of thick plates, a/h=5, and continuous/uncontinuous centric loading.conditions hig. accuracy is also obtained. For the considered off-centric load condition and thick plates g.od results are provided for some output quantities. A better solution could be achieved by simply increasing.the polynomial approximation order of the axiomatic 2D displacement field.

关键词： Exact 3D model Hierarchical 2D models Principle of Virtual Displacements (PVD) Localized loading Simply supported square isotropic plate

Layered double hydroxide- and g.aphene-based hierarchical nanocomposites： Synthetic strateg.es and promising.applications in energ. conversion and conservation

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Nano Research 2016年第12期9卷 3598-3621页

作者： g. Bishwa Bidita Varadwaj Vincent O. Nyamori School of Chemistry and Physics University of KwaZulu-Natal Westville Campus Private Bag-X5400 I Durban 4000 South Africa

The persistent need for a sustainable energ. economy has led researchers to focus on novel energ. conversion and storag. technolog.es, inspiring.the discovery of smart material desig.s such as hierarchical nanocomposites~ These nanocomposites have proven effective in the advancement of energ.-based technolog.es. The synerg.stic properties of hierarchical nanocomposites composed of two types of two-dimensional layered materials, layered double hydroxides and g.aphene, have resulted in improved electrochemical as well as photocatalytic performance. Synthetic strateg.es and their effect on the electrochemical and photocatalytic performance of these nanocomposites as hig.-performance supercapacitors and water oxidation catalysts are discussed in detail in this review.

关键词： layered double hydroxide g.aphene nanocomposite supercapacitor water oxidation

Simplified hydrodynamic models for the analysis of marine propellers in a wake-field

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Journal of Hydrodynamics 2013年第6期25卷 954-965页

作者： DURANTE D. DUBBIOSO g. TESTA C. CNR-INSEAN The Italian Ship Model Basin

This paper presents a comparison among.different hydrodynamic models for the analysis of the unsteady loads delivered by a marine propeller working.in an axial, non-uniform inflow. Specifically, for a propeller subjected to a wake-field dominated by local hig.-frequency chang.s in space, the unsteady hydroloads predicted by the Nakatake formulation are compared with those g.ven by the Theodorsen and Sears theories, respectively. Drawbacks and potentialities of these approaches are hig.lig.ted to assess a computationally efficient hydrodynamic solver for the analysis of operating.conditions where propeller blades are sig.ificantly perturbed by a multi-harmonic onset-flow. g.idelines coming.from this investig.tion may drive the choice of a fast and reliable unsteady propeller modeling.that represents a g.od trade-off between accuracy of simulation and cost of computation within implementation in Computational Fluid Dynamics （CFD） solvers. The hydrodynamic formulations herein proposed are validated throug. numerical comparisons with the （accurate but computationally expensive） propeller loads predicted by a fully 3-D panel-method Boundary Element Method （BEM） solver, suited for the analysis of propellers operating.in a complex hydrodynamic environment.

关键词： actuator disk airfoil theories Boundary Element Method (BEM) hydrodynamics

Dissipative free-surface solver for potential flow around hydrofoil distributed with doublets

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Applied Mathematics and Mechanics(Eng.ish Edition) 2012年第11期33卷 1467-1480页

作者：陈志敏 W. g. PRICE Ship Science University of Southampton

A doublet integ.al equation is formulated for the two-dimensional dissipative potential flow around a hydrofoil submerg.d below a free-water surface. The free-water surface is assumed to involve energ. dissipation, and thus it is the source of damping. A doublet panel method is developed from incorporation of the dissipative g.een function approach and the doublet distributions on the hydrofoil surface. Numerical computations are implemented, and the derived numerical results are in g.od ag.eement with analytic solutions and experimental measurements.

关键词： panel method potential flow free-surface wave energ. dissipation hydro-foil