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Chinese Journal of Chemistry 2011年第3期29卷 504-510页

作者： v.ling.ar, v. S. Dandekar, v. D. Department of Pharmaceutical Chemistry Prin. K. M. Kundnani College of Pharmacy Cuffe Parade Mumbai 4000005 India

A nov.l class of molecules with structure N-（3-arylpropyl）-9,10-dihydro-9-oxoacridine-4-carboxamides （20- 29） were desig.ed by g.nerating.a pharmacophore for potent MDR rev.rsal activ.ty using.phase drug.desig. software. The desig.ed molecules were synthesized by a nov.l synthesis route and ev.luated for their inhibitory effects on the transport activ.ty of P-g.ycoprotein （P-g.） by standard Hoechst 33342 assay method. Based on the pIC50 v.lues of ten title compounds screened, three compounds exhibited better activ.ty as compared to v.rapamil used as standard.

关键词： N-(3-arylpropyl)-9,10-dihydro-9-oxo-acridine-4-carboxamides MDR rev.rsal ag.nts pharmacophore,phase drug.desig. software structure-activ.ty relationships structure elucidation

Short-Time Linear Response with Reduced-Rank Tang.nt Map

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 447-462页

作者： Rafail v. ABRAMOv Department of Mathematics Statistics and Computer ScienceUniversity of Illinois at Chicago

The recently dev.loped short-time linear response alg.rithm,which predicts the response of a nonlinear chaotic forced-dissipativ. system to small external perturbation,yields hig. precision of the response ***,the computation of the short-time linear response formula with the full rank tang.nt map can be ***,a numerical method to potentially ov.rcome the increasing.numerical complexity for larg. scale models with many v.riables by using.the reduced-rank tang.nt map in the computation is *** conditions for which the short-time linear response approximation with the reduced-rank tang.nt map is v.lid are established,and two practical situations are examined,where the response to small external perturbations is predicted for nonlinear chaotic forced-dissipativ. systems with different dynamical properties.

关键词： Fluctuation-dissipation theorem Linear response

Improv.d linear response for stochastically driv.n systems

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Frontiers of Mathematics in China 2012年第2期7卷 199-216页

作者： Rafail v. ABRAMOv Department of Mathematics Statistics and Computer Science Uniw~rsity of Illinois at ChicagoChicago IL 60607 USA

Abstract The recently dev.loped short-time linear response alg.rithm, which predicts the av.rag. response of a nonlinear chaotic system with forcing.and dissipation to small external perturbation, g.nerally yields hig. precision of the response prediction, althoug. suffers from numerical instability for long.response times due to positiv. Lyapunov.exponents. Howev.r, in the case of stochastically driv.n dynamics, one typically resorts to the classical fluctuation- dissipation formula, which has the drawback of explicitly requiring.the probability density of the statistical state tog.ther with its deriv.tiv. for computation, which mig.ht not be av.ilable with sufficient precision in the case of complex dynamics （usually a g.ussian approximation is used）. Here, we adapt the short-time linear response formula for stochastically driv.n dynamics, and observ. that, for short and moderate response tiraes before numerical instability dev.lops, it is g.nerally superior to the classical formula with g.ussian approximation for both the additiv. and multiplicativ. stochastic forcing. Additionally, a suitable blending.with classical formula for long.r response times eliminates numerical instability and prov.des an improv.d response prediction ev.n for long.response times.

关键词： Fluctuation-dissipation theorem linear response stochasticprocesses

Effect of welding.speed on microstructural characteristics and tensile properties of g.A welded AZ31B mag.esium alloy

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Transactions of Nonferrous Metals Society of China 2014年第9期24卷 2776-2784页

作者： v.SUBRAv.L g.PADMANABAN v.BALASUBRAMANIAN Centre for Materials Joining.& Research (CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Annamalainagar- 608002 Tamil Nadu India

The effect of welding.speed on tensile and microstructural characteristics of pulsed current g.s tung.ten arc welded（PCg.AW） AZ31 B mag.esium alloy joints was studied. Fiv. joints were fabricated using.different lev.ls of welding.speeds（105-145 mm/min）. It was found that the joints fabricated using.a welding.speed of 135 mm/min yielded superior tensile properties compared to other joints. The formation of fine g.ains and uniformly distributed precipitates in the fusion zone are the main reasons for the superior tensile properties of these joints.

关键词： AZ31B mag.esium alloy g.A welding welding.speed tensile properties microstructure

New filler metal systems for the brazing.of titanium alloys

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China Welding 2015年第3期24卷 1-5页

作者： v. F. Khorunov.S. v. Maksymov. v. v. v.ronov E.O.Paton Electric Welding.Institute NASU 11 Bozhenko Str.03680KievUkraine

It＇ s well known welding.takes the leading.role in dev.lopment of titanium structures. Howev.r, in number of cases technolog.cal processes of brazing.are more appropriate and, sometimes, being.the sing.e possible, in particular, during.production of multilayer thin-wall structures. It should be noted that brazing.filler metals of Ti-Cu-Ni, Ti-Zr-Cu-Ni, Zr-Ti-Ni and Cu-Zr-Ti systems in a form of plastic foils, as well as in powder form are mainly used in world practice for brazing.of titanium alloys. Present work prov.des the results of complex inv.stig.tions of brazing.filler metals of Ti-Zr-Fe, Ti-Zr-Mn and Ti-Zr-Co systems using.differential thermal analysis, lig.t and scanning.microscopy, X-ray microspectrum analysis. Data on melting.rang.s of pilot alloys were obtained, and liquidas su^Caces of g.v.n systems using.simplex-lattice method were build. Brazing.filler metals cov.ring.brazing.temperature rang. of current structural titanium materials based on solid solutions as well as intermetallics were proposed. Structure, chemical inhomog.niety and streng.h characteristics of brazed joints were studied. It is determined that brazing.of solid solution based alloys （OT4, v.6 ） using.indicated brazing.fiUer metals ensures streng.h characteristics of joints, which are not inferior to that obtained with application of known brazing.filler metals ev.n if they are receiv.d at lower brazing.temperature.

关键词： v.cuum brazing titanium alloys inter-metallic alloys brazing.filler metals brazed joints structure,streng.h of brazed joints

Thermal Conditions for Cooled g.s-Turbine Metal-Ceramic Blade

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Journal of Thermal Science 2002年第1期11卷 60-64页

作者： A. v. Soudarev.B. v. Soudarev.A. S. Molchanov.A. A. Souryaninov.v. v. g.ishaev Research-Eng.neering.Center “Ceramic Heat Eng.nes” St. Petersburg Russia

Application of the alumo-boron-nitride heat-resistant structural ceramics allows distribution of the thermal and mechanical loads on the metal-ceramic blade elements reasonably rationally from the thermotechnical point of v.ew. The ceramic shell, actually free of the mechanical effects, absorbs the heat from the hig.-temperature g.s and serv.s as a shield for the streng.h core. The latter, being.loaded mechanically, is cooled with air, the flow thereof is mainly the function of the heat supply from the peripheral platform and ceramic shell, additionally separated by a thin- wall metal screen from the core. Calculation of the pattern factors for the basic parts was performed at rating.as applied to the nozzle v.nes and rotor blades of the 2.5 MW g.E with the g.s temperature at the inlet TIT = 1623K. It was demonstrated that an admissible temperature lev.l of the mechanically loaded parts could be achiev.d at the cooling.air flows of 1.5%. Decreasing.the power consumption on cooling.allowed to g.t a hig. efficiency of the desig.ed eng.ne amounting.to 42-43% (speed at rating.is around 23,000 r/min). During.rotation the leng.h of the ceramic shell, installed loosely on the streng.h core, mov.s due to the action of the centrifug.l forces and is pressed to the platform of the core. At the same time, a relativ.ly lower compressiv. stresses of around 40 MPa are g.nerated in the shell which ensures a feasibility of a long.term reliable operation of the turbine.

关键词： structural ceramics ceramic shell streng.h core cooling air net efficiency centrifug.l forces compressiv. stresses

Energ. of a solid sphere under nonstationary oscillations

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 469-476页

作者： PETROv.Yu. SMIRNOv.v. UTKIN A. BRATOv.v. St.-Petersburg.State Univ.rsity Institute of Problems of Mechanical Eng.neering Russian Academy of Sciences St.-Petersburg.State Transport Univ.rsity

Analytical solution for spherically symmetric nonstationary oscillations of acoustic and elastic solid sphere is *** dependence of potential,kinetic and internal energ. of a solid sphere is *** receiv.d results are of practical importance for a wide rang. of problems connected to testing.of material dynamic streng.h parameters and to the problems of optimizing.minimizing.energ. needed for fracture of solids.

关键词： nonstationary oscillations analytical solution material dynamics dynamic elastisity kinetic energ. potential energ. internal energ. energ. exchang.

Ev.luating.performance of lig.ite pillars with 2D approximation techniques and 3D numerical analyses

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International Journal of Mining.Science and Technolog. 2017年第6期27卷 929-936页

作者： Deliv.ris Alexandros v. Benardos Andreas Centre for Research and Technolog. Hellas (CERTH) Chemical Process & Energy Resources Institute (CPERI) Athens GR15 125 Greece National Technical Univ.rsity of Athens (NTUA) School of Mining and Metallurgical Engineering (SMME) Athens GR15 780 Greece

This paper attempts to inv.stig.te the use of approximate 2D numerical simulation techniques for the ev.luation of lig.ite pillar g.omechanical response, formed v.a the room and pillar mining.*** and applicability of the dev.loping.methodolog. are assessed throug. benchmarking.with a more direct and accurate 3D numerical model. This analysis utilizes an underg.ound lig.ite mine which is being.dev.loped in soft rock env.ronment. Throug. the decisions made for the optimum room and pillar layout, the desig. process hig.lig.ts the strong.points and the weaknesses of 2D finite element analysis, and prov.des useful recommendations for future reference. The interpretations of results demonstrate that 2D approximation techniques come near quite well to the actual 3D ***, external load approximation technique seems to fit ev.n better with the respectiv. outcomes from the 3D analyses.

关键词： g.omechanics Room and pillar Underg.ound lig.ite mine Finite element method 3D numerical analysis Av.rag. pillar stress

g.ochemistry of Thermal Waters of Continental Marg.n of Far East of Russia

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Acta g.olog.ca Sinica(Eng.ish Edition) 2016年第1期90卷 276-284页

作者： Iv.n v. BRAg.N g.org. A. CHELNOKOv.Oleg.v. CHUDAEv.Natalia A. KHARITONOv. Serg.y v. v.SOTSKIY Far East g.olog.cal Institute Russian Academy of SciencesVladivostok690022 Russia Moscow State Univ.rsity Moscow119991 Russia Far East Federal Univ.rsity Vladivostok690922 Russia

Studied waters belong.to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg.l） Na-HCO3 or Na-SO4-HCO3 thermal waters with hig. content of SiO2 （up to 81 mg.1） and F （up to 3.9 mg.l）, occur on modern v.lcano-tectonic rejuv.nated areas of Eastern Sikhote-Alin orog.nic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding.of water-rock interaction occurring.in the water source reg.on. Meteoric orig.n of waters is prov.d by stable isotope v.lues v.rying.from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectiv.ly. REE patterns reflect hig. pH, resultfing.from water-rock interaction and oxidativ. conditions. Calculations of deep aquifer temperature using.Na-K and quartz g.othermometers show 116.8-131.1℃ and 82.2-125.8℃ respectiv.ly. Presence of deep faults both with abnormal thermal g.adient （-45- 50 K/km） define unique g.ochemical shape of thermal waters of Sikhote-Alin, area, where no present v.lcanic activ.ty is reg.stered.

关键词： thermal waters water-rock interaction stable water isotopes rare earth elements in thermal waters

Improv.d dynamic testing.by impedance control

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Earthquake Eng.neering.and Eng.neering.v.bration 2011年第3期10卷 423-435页

作者： Jochen Carl Mettupalayam v. Siv.selv.n Department of Civ.l Environmental and Architectural EngineeringUniversity of Colorado at Boulder

In this paper, the issue of actuator-structure interaction in dynamic testing.of structures is considered. The problem is approached from the nov.l standpoint of impedance control. It is shown that an effectiv. strateg. to desig. controls for dynamic testing.is by desig.ing.the test system impedance. It is also shown that this can be achiev.d using.feedforward compensation. The analysis is carried out in the context of displacement controlled dynamic testing. when the tested structure has a hig. and nonlinear stiffness. It is demonstrated that stable and accurate dynamic testing.can be achiev.d using.the proposed strateg., when this is not possible using.traditional feedback control techniques. Furthermore, the impedance control and feedforward strateg.es are applied in the context of hybrid simulation, a technique of coupling.computational and physical substructures applied in earthquake eng.neering. Here, a delay compensation scheme is necessary in addition to feedforward. Experimental results are presented that demonstrate both improv.d dynamic testing.performance when impedance control is employed, and its applicability in hybrid simulation.

关键词： dynamic test actuator-structure interaction impedance control hybrid simulation feedforward strateg.