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Chinese Journal of.Structural Chemistry 2007年第7期26卷 843-849页

作者：吉智 abraham f. jalbout 李俊篯 Department of.Chemistry Fuzhou University Fuzhou Institute of.Chemistry National Autonomous University of Mexico Mexico City MX

Density f.nctional theory periodic slab calculations were carded out f.r CO adsorption on a series of.Mo modif.ed Pt（111） surf.ces to provide an insight into the interaction between CO and doped metal surf.ce, an important issue in CO oxidation as well as in promotion and poisoning ef.ects of.catalysis. The modif.cation of.adsorption properties with respect to those of.adsorption on the pure Mo（110） and Pt（111） is described in terms of.changes in the adsorption energies, adsorption sites and vibrational properties occurring upon alloying. We believe that the present Df. calculations can provide important inf.rmation into optimal alloy composition f.r CO-tolerance, which is not easily obtained by experimental methods.

关键词： density f.nctional calculations adsorption molybdenum platinum carbon monoxide bimetallic surf.ces

Condensed Extended Hyper-Wiener Index

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Chinese Journal of.Structural Chemistry 2008年第9期27卷 1134-1140页

作者：李新华 abraham f.jalbout 吉智 College of.Chemistry and Materials Engineering Wenzhou University Instituto de Quimica Universidad Nacional Autonoma de MexicoMexico D.F Instituto de f.sica Universidad Nacional Autonoma de MexicoMexico D.F

According to the def.nitions of.molecular connectivity and hyper-Wiener index, a novel set of.hyper-Wiener indexes （Dn, ^mDn） were def.ned and named as condensed extended hyper-Wiener index, the potential usef.lness of.which in QSAR/QSPR is evaluated by its correlation with a number of.C3-C8 alkanes as well as by a f.vorable comparison with models based on molecular connectivity index and overall Wiener index.

关键词： hyper-Wiener index (R) condensed extended hyper-Wiener index molecular connectivity index

Theoretical Study of.the N-NO_2 Bond Dissociation Energies f.r Energetic Materials with Density f.nctional Theory

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Chinese Journal of.Structural Chemistry 2008年第6期27卷 677-682页

作者：李小红汤正新 abraham f.jalbout 张现周程新路 College of.Science Henan University of Science and Technology NASA Astrobiology Institute Department of.Chemistry The University of ArizonaTucsonAZ 5721 USA Department of.Physics Henan Normal University Institute of.Atomic and Molecular Physics Sichuan University

The N-NO2 bond dissociation energies （BDEs） f.r 7 energetic materials were computed by means of.accurate density f.nctional theory （B3LYP, B3PW91 and B3P86） with 6-31G＊＊ and 6-311G＊＊ basis sets. By comparing the computed energies and experimental results, we f.nd that the B3P86/6-311G＊＊ method can give good results of.BDE, which has the mean absolute deviation of.1.30kcal/mol. In addition, substituent ef.ects were also taken into account. It is noted that the Hammett constants of.substituent groups are related to the BDEs of.the N-NO2 bond and the bond dissociation energies of.the energetic materials studied decrease when increasing the number of.NO2 group.

关键词： density f.nctional theory bond dissociation energy energetic materials,substituent ef.ect

Inf.uences of.Temperature and Solvent Ions in Solution on States and Properties of.Deoxyribonucleic Acid （DNA）

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Communications in Theoretical Physics 2005年第6期43卷 1141-1152页

作者： PANGXiao-f.ng f.NGYuan-Ying ZHANGHuai-Wu A.f.jalbout DONGRui-Xin Instituteof.if.ScienceandTechnology UniversityofElectronicScienceandTechnologyofChinaChengdu610054China／／DepartmentofPhysicsNationalUniversityofSingaporeSingapore119260 Departmentof.hysics NationalUniversityofSingaporeSingapore119260 Collegeof.olid-StateElectronics UniversityofElectronicScienceandTechnologyofChinaChengdu610054China Departmentof.hysics DillardUniversityNewOrleansLA70112USA Instituteof.if.ScienceandTechnology UniversityofElectronicScienceandTechnologyofChinaChengdu610054China

We here study the inf.uences of.the temperature and solvent ions in solution on the states and properties of.DNA by a new dynamical model. This model admits three degrees of.f.eedom per base-pair: two displacement variables related to the vibrations of.the hydrogen atom in the hydrogen bonds and base (nucleotide), respectively, and an angular variable related to the rotation of.each base, which delineate dif.erent f.rms of.motion of.the hydrogen atom and bases and the relations among them. In this -model we stress specially the important role of.the hydrogen atom in the hydrogen bonds of.the bases in the dynamics of.DNA. According to their properties of.motion we give the Hamiltonian of.the system and the corresponding equations of.motion, and End out their soliton solutions. The solitons f.rmed by the displacements of.the hydrogen atoms and bases and their rotations are the excitation states arising f.om the energy absorbed by the DNA working at the biological temperature. We give f.rther the f.ee energy of.the thermal excitation state in DNA system by transf.r integral way and End out the corresponding specif.c heat. The specif.c heat increases with the increasing of.the temperature and concentration of.the solvent ions in the solution, but is not linear changes in the region of.high temperature. If.compared with experimental data, they are approximately consistent. Meanwhile we End that the solvent ion conceptration inf.uences seriously on the stability, states, and conf.gurations of.DNA.

关键词： dynamical property DNA nonlinearity soliton solvent ion specif.c heat