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Applic.tion of Hartree-Foc. Method for Modeling of Bioac.ive Molec.les Using SAR and QSPR

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c.mputational Molec.lar Biosc.enc. 2014年第1期4卷 1-24页

作者： c.eydson B. R. Santos c.eison c. Lobato Franc.naldo S. Braga Sílvia S. S. Morais c.sar F. Santos c.io P. Fernandes Davi S. B. Brasil Lorane I. S. Hage-Melim williams j. c. macêdo j.sé c. T. c.rvalho Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Laboratory of Drug Researc. School of Pharmaceutical Sciences Federal University of Amap&#225 Macap&#225 Brazil Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Institute of Tec.nology Federal University of Par&#225 Bel&#233m Brazil Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Postgraduate Program in Biotec.nology and Biodiversity-Network BIONORTE Campus Universit&#225rio Marco Zero Macap&#225 Brazil Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Postgraduate Program in Biotec.nology and Biodiversity-Network BIONORTE Campus Universit&#225rio Marco Zero Macap&#225 Brazil Laboratory of Drug Researc. School of Pharmaceutical Sciences Federal University of Amap&#225 Macap&#225 Brazil Laboratory of Modeling and c.mputational c.emistry Federal University of Amap&#225 Macap&#225 Brazil Postgraduate Program in Biotec.nology and Biodiversity-Network BIONORTE Campus Universit&#225rio Marco Zero Macap&#225 Brazil Laboratory of Drug Researc. School of Pharmaceutical Sciences Federal University of Amap&#225 Macap&#225 Brazil Laboratory of Statistic.l and c.mputational Modeling University of the State of Amap&#225 Macap&#225 Brazil

The c.ntral importanc. of quantum c.emistry is to obtain solutions of the Sc.r?dinger equation for the ac.urate determination of the properties of atomic.and molec.lar systems that oc.urred from the c.lc.lation of wave func.ions ac.urate for many diatomic.and polyatomic.molec.les, using Self c.nsistent Field method (Sc.). The applic.tion of quantum c.emic.l methods in the study and planning of bioac.ive c.mpounds has bec.me a c.mmon prac.ic. nowadays. From the point of view of planning it is important to note, when it c.mes to the use of molec.lar modeling, a c.llec.ive term that refers to methods and theoretic.l modeling and c.mputational tec.niques to mimic.the behavior of molec.les, not intend to reac. a bioac.ive molec.le simply through the use of c.mputer programs. The c.oic. of method for energy minimization depends on fac.ors related to the size of the molec.le, parameters of availability, stored data and c.mputational resourc.s. Molec.lar models generated by the c.mputer are the result of mathematic.l equations that estimate the positions and properties of the elec.rons and nuc.ei, the c.lc.lations exploit experimentally, the c.arac.eristic. of a struc.ure, providing a new perspec.ive on the molec.le. In this work we show that studies of Highest Oc.upied Molec.lar Orbital Energy (HOMO), Low Unoc.upied Molec.lar Orbital Energy (LUMO) and Map of molec.lar elec.rostatic.potential (MEP) using Hatree-Foc. method with different basis sets (HF/3-21G*, HF/3-21G**, HF/6-31G, HF/6-31G*, HF/6-31G** and HF/6-311G), that are of great importanc. in modern c.emistry, bioc.emistry, molec.lar biology, and other fields of knowledge of health sc.enc.s. In order to obtain a signific.nt c.rrelation, it is essential that the desc.iptors are used appropriately. Thus, the quantum c.emic.l c.lc.lations are an attrac.ive sourc. of new molec.lar desc.iptors that c.n, in princ.ple, express all the geometric.l and elec.ronic.properties of molec.les and their interac.ions with biologic.l

关键词： Molec.lar Modeling Meps Maps Orbital Frontier Quantum c.emic.l Methods

HYERS—ULAM—RASSIAS STABILITY OF QUADRATIc.FUNc.IONAL EQUATIONS IN BANAc. MODULES OVER A c.＊—ALGEBRA

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c.inese Annals of Mathematic.,Series B 2003年第2期24卷 261-266页

作者： c. PARK j. PARK j. SHIN Department of Mathematic. Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.

The authors prove the Hyers-Ulam-Rassias stability of the quadratic.mapping in Banac.modules over a unital c.-algebra, and prove the Hyers-Ulam-Rassias stability of the quadratic.apping in Banac. modules over a unital... 详细信息

关键词： Stability B-quadratic Func.ional equation Banac. module over Banac. algebra

Molec.lar level simulations on multi-c.mponent systems --a morphology predic.ion method

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Frontiers of c.emic.l Sc.enc. and Engineering 2013年第1期7卷 49-54页

作者： c. Sc.MIDT j. ULRIc. c.nter for Engineering Sc.enc. Thermal Process Engineering Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

The c.ystal morphology grown from a solution c.mposed of an organic.solvent, solute and additive c.n be predic.ed reliably by a c.mputational method. Modeling the supersaturated solution as liquid phase is ac.ieved by employing c.mmerc.al software. The molec.lar c.mposition of this solution is a required input parameter. The fac. spec.fic.diffusion c.effic.ent of the solid （c.ystal surfac.） and liquid （solution） system is determined using the molec.lar dynamic. proc.dure. The obtained diffusion c.effic.ent is related to the spec.fic.fac. growth rate via the attac.ment energy of the pure morphology. The signific.nt improvements are ac.ieved in the morphology predic.ion bec.use the investigation on the fac. growth rates in a c.mplex growth environment （as multi-c.mponent solutions with additives） c.n be c.rried out based on the diffusion c.effic.ents.

关键词： c.ystallization morphology molec.lar dynamic. solution

Elec.ro-osmotic.flow of a sec.nd-grade fluid in a porous mic.oc.annel subj.c. to an Ac.elec.ric.field

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j.urnal of Hydrodynamic. 2013年第2期25卷 309-316页

作者： MISRA j. c. c.ANDRA S. Department of Mathematic. Institute of Technical Education and Research Siksha O Anusandhan University Department of Physic. Sabang S. K. Mahavidyalaya Vidyasagar University

Studies on elec.ro-osmotic.flows of various types of fluids in mic.oc.annel are of great importanc. owing to their multifold applic.tions in the transport of liquids, partic.larly when the ionized liquid flows with respec. to a c.arged surfac. in the presenc. of an external elec.ric.field. In the c.se of visc.elastic.fluids, the volumetric.flow rate differs signific.ntly from that of Newtonian fluids, even when the flow takes plac. under the same pressure gradient and the same elec.ric.field. With this end in view, this paper is devoted to a study c.nc.rning the flow pattern of an elec.ro-osmotic.flow in a porous mic.oc.annel, whic. is under the ac.ion of an alternating elec.ric.field. The influenc. of various rheologic.l and elec.ro-osmotic.parameters, e.g., the Reynolds number, Debye-Huc.el parameter, shape fac.or and fluid visc.elastic.ty on the kinematic. of the fluid, has been investigated for a sec.ndgrade visc.elastic.fluid. The problem is first treated by using analytic.l methods, but the quantitative estimates are obtained numeric.lly with the help of the software MATHEMATIc.. The results presented here are applic.ble to the c.ses where the c.annel height is muc. greater than the thic.ness of the elec.ric.l double layer c.mprising the Stern and diffuse layers. The study reveals that a larger value of the Debye-Huc.el parameter c.eates sharper profile near the wall and also that the veloc.ty of elec.ro-osmotic.flow inc.eases as the permeability of the porous mic.oc.annel is enhanc.d. The study further shows that the elec.ro-osmotic.flow dominates at lower values of Reynolds number. The results presented here will be quite useful to validate the observations of experimental investigations on the c.arac.eristic. of elec.ro-osmotic.flows and also the results of c.mplex numeric.l models that are nec.ssary to deal with more realistic.situations, where elec.ro-osmotic.flows c.me into the pic.ure, as in blood flow in the mic.o-c.rc.latory system subj.c. to an elec.

关键词： elec.ric.l double layer Debye length sec.nd-grade fluid Ionic.energy

Molec.lar Frame Photoemission： Probe of the Photoionization Dynamic. for Molec.les in the Gas Phase

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c.inese j.urnal of c.emic.l Physic. 2009年第2期22卷 178-186页

作者： D. dowek Y. j. Pic.rd P. Billaud c. Elkharrat j. c. Houver Université Paris-Sud 11 UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-Sud 91405 Orsay France c.RS UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-5ud 91405 Orsay France

Molec.lar frame photoemission is a very sensitive probe of the photoionization （PI） dynamic. of molec.les. This paper reports a c.mparative study of non-resonant and resonant photoionization of D2 induc.d by VUV c.rc.larly polarized sync.rotron radiation at SOLEIL at the level of the molec.lar frame photoelec.ron angular distributions （MFPADs）. We use the vec.or c.rrelation method whic. c.mbines imaging and time-of-flight resolved elec.ron-ion c.inc.denc. tec.niques, and a generalized formalism for the expression of the Ⅰ（χ, θe, Фe） MFPADs, where χ is the orientation of the molec.lar axis with respec. to the light quantization axis and （θe, Фe） the elec.ron emission direc.ion in the molec.lar frame. Selec.ed MFPADs for a molec.le aligned parallel or perpendic.lar to linearly polarized light, or perpendic.lar to the propagation axis of c.rc.larly polarized light, are presented for dissoc.ative photoionization （DPI） of D2 at two photon exc.tation energies, hv=19 eV, where direc. PI is the only c.annel opened, and hv=32.5 eV, i.e. in the region involving resonant exc.tation of Q1 and Q2 doubly exc.ted state series. We disc.ss in partic.lar the properties of the c.rc.lar dic.roism c.arac.erizing photoemission in the molec.lar frame for direc. and resonant PI. In the latter c.se, a remarkable behavior is observed whic. may be attributed to the interferenc. oc.urring between undistinguishable autoionization dec.y c.annels.

关键词： Dissoc.ative photoionization Molec.lar frame photoemission c.rc.lar dic.roism in photoemission Autoionization dynamic. Sync.rotron radiation Vec.or c.rrelation

OPTIMAL AND PRESSURE-INDEPENDENT L2 VELOc.TY ERROR ESTIMATES FOR A MODIFIED c.OUZEIX-RAVIART STOKES ELEMENT WITH BDM REc.NSTRUc.IONS

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j.urnal of c.mputational Mathematic. 2015年第2期33卷 191-208页

作者： c. Brennec.e A. Linke c. Merdon j. Sc.oberl Eidgen6ssisc.e Tec.nisc.e Hoc.sc.ule Ziiric. Departement Mathematik Riimistr. 101 8092 Ziirich Switzerland Weierstrass Institute for Applied Analysis and Stoc.astic. Mohrenstr. 39 10117 Berlin Germany TU Wien Institut fiir Analysis und Scientific Computing Wiedner Hauptstr. 8-10//1011040 Wien Austria

Nearly all inf-sup stable mixed finite elements for the inc.mpressible Stokes equations relax the divergenc. c.nstraint. The pric. to pay is that a priori estimates for the ve- loc.ty error bec.me pressure-dependent, while divergenc.-free mixed finite elements de- liver pressure-independent estimates. A rec.ntly introduc.d new variational c.ime using lowest-order Raviart-Thomas veloc.ty rec.nstruc.ions delivers a muc. more robust modi- fied c.ouzeix-Raviart element, obeying an optimal pressure-independent disc.ete H1 ve- loc.ty estimate. Refining this approac., a more sophistic.ted variational c.ime employing the lowest-order BDM element is proposed, whic. also allows proving an optimal pressure- independent L2 veloc.ty error. Numeric.l examples c.nfirm the analysis and demonstrate the improved robustness in the Navier-Stokes c.se.

关键词： Variational c.ime c.ouzeix-Raviart finite element Divergenc.-free mixed me-thod Inc.mpressible Navier-Stokes equations A priori error estimates.

Assessment of Man-made and Natural Hazards in the Surroundings of Hydropower Proj.c.s under c.nstruc.ion in the Beas Valley of Northwestern Himalaya

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j.urnal of Mountain Sc.enc. 2007年第3期4卷 221-236页

作者： Sanj.ev Sharma j.gdish c. Kuniyal j. c. Sharma G.B. Pant Institute of Himalayan Environment & Development Himachal UnitMohal-Kullu 175 126Himachal Pradesh India Department of Geography Himachal Pradesh University

Mountain ec.system, on the earth, has plenty of natural resourc.s. In Himachal Pradesh all the rivers are snowfed and therefore ric. in water resourc.s. These resourc.s have been supporting enough for the generation of elec.ric.ty through introduc.ng hydropower proj.c.s sinc. the last dec.de However, every developmental ac.ivity has its own negative impac.s on the surrounding environment. Due to the fragile nature of topography and delic.c. of ec.logy of the Himalaya, it results in lot of disturbanc.s bec.use of high degree of human interferenc.s like c.nstruc.ion of maj.r hydropower proj.c.s. The inc.eased extent of geologic.l hazards, suc. as landslides, roc. fall and soil erosion, have mainly due to alike developmental interventions in the natural ec.system. So understanding and analysing suc. impac.s of the hydropower proj.c.s have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study, therefore, foc.ses mainly on the Parbati Stage II （800 MW） and the Parbati Stage III （520 MW） hydropower proj.c.s; both of whic. fall within the Kullu distric. of Himachal Pradesh. Based on the perc.ption survey of the loc.l c.mmunities, the existing land use pattern, status of total ac.uired land of the residents by hydropower proj.c.s, frequent natural hazards and resultant loss to the loc.l c.mmunities due to upc.ming c.nstruc.ion of hydropower proj.c.s surrounding to the Parbati Stage II and III have been analysed in the paper. Also, the preventive measures to mitigate these adverse impac.s have been suggested to strengthen these proj.c.s in ec.-friendly manner in the mountain c.ntext.

关键词： Hydropower proj.c. under c.nstruc.ion loc.l c.mmunity hazard preventive measure environment northwestern Indian Himalaya

Manifestation of external field effec. in time-resolved photo-dissoc.ation dynamic. of LiF

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c.inese Physic. B 2013年第7期22卷 140-147页

作者：孟庆田 A. j. c. Varandas Department of Physic. Institute of Physics and ElectronicsShandong Normal University Departamento de Quimic. Universidade de Coimbra

The photo-dissoc.ation dynamic. of LiF is investigated with newly c.nstruc.ed ac.urate ab initio potential energy c.rves （PEc.） using the time-dependent quantum wave pac.et method. The osc.llations and dec.y of the wave pac.et on the adiabats as a func.ion of time are given, whic. c.n be c.mpared with the femtosec.nd transition-state （FTS） spec.rosc.py. The photo-absorption spec.ra and the kinetic.energy distribution of the dissoc.ation fragments, whic. c.n exhibit the vibration-level struc.ure and the dispersion of the wave pac.et, respec.ively, are also obtained. The investigation shows a blue shift of the band c.nter for the photo-absorption spec.rum and multiple peaks in the kinetic.energy spec.rum with inc.easing laser intensity, whic. c.n be attributed to external field effec.s. By analyzing the osc.llations of the wave pac.et evolving on the upper adiabat, an approximate inversion sc.eme is devised to roughly deduc. its shape.

关键词： photo-dissoc.ation dynamic. time-dependent wave pac.et method photo-absorption spec.ra external field effec.

Effec.s of adenosine triphosphate c.nc.ntration on motor forc. regulation during skeletal musc.e c.ntrac.ion

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Ac.a Mec.anic. Sinic. 2017年第2期33卷 243-249页

作者： j. Wei c. dong B. c.en Department of Engineering Mec.anic. Zhejiang UniversityHangzhou 310058 China

We employ a mec.anic.l model of sarc.mere to quantitatively investigate how adenosine triphosphate (ATP) c.nc.ntration affec.s motor forc. regulation during skeletal musc.e c.ntrac.ion. Our simulation indic.tes that there c.n be negative c.oss-bridges resisting c.ntrac.ion within the sarc.mere and higher ATP c.nc.ntration would dec.ease the resistanc. forc. from negative c.oss-bridges by promoting their timely detac.ment. It is revealed that the motor forc. is well regulated only when ATP c.nc.ntration is above a c.rtain level. These predic.ions may provide insights into the role of ATP in regulating c.ordination among multiple motors.

关键词： Motor forc. regulation ATP Musc.e c.ntrac.ion Myosin