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Chinese Journal of Chemical Physics 2018年第4期31卷 446-456,614页

作者： Haobin Wang Xinzijian Liu Jian Liu Department of chemistry University of Colorado DenverDenver CO 80217-3364USA Beijing National Laboratory for Molecular Sciences Institute of Theoretical and Computational ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBelling 100871China

An efficient and accurate method for computing the equilibriurn reduced density matrix is presented for treating open quantum systems characterized by the systern-bath model. The method employs the rnultilayer nmlticonfiguration tirne-dependent Hartree theory for imag- inary time propagation and an importance sampling procedure for calculating the quantum mechanical trace. The method is applied to the spin-boson Harniltonian, which leads to ac- curate results in agreement with those produced by the rnulti-electronic-state path integral molecular dynamics method.

关键词： Multilayer multiconfiguration time-dependent Hartree Path integral riurn reduced density matrix Imaginary time propagation

ELECTRONIC ENERGY BAND STRUCTURE OF MOLECULAR CRYSTAL TTF-TCNQ——CHANGE OF ENERGY BAND STRUCTURE DURING PEIERLS PHASE TRANSITION

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Science China chemistry 1986年第7期29卷 698-708页

作者：严继民张启元刘津琨 institute of chemistry Academia. Sinica Beijing

In this paper, the electronic energy bands of the molecular crystal TTF-TCNQ have been calculated. The results demonstrate that the positions and the widths of the energy bands of this crystal conform to the rules given by our previous paper exactly, i.e. the positions of the energy bands of crystal orbitals are determined by the energy levels of corresponding molecular orbitals of the isolated molecules, and the widths of the energy bands are determined by the interaction between the molecular orbitals belonging to different molecules in the crystal. The results also demonstrate that the dimerization which appears after Peierls phase transition has a considerable effect on band widths. The dimerization causes the band widths of TTF and TCNQ columns to become narrow sharply. According to the relationship between the mobility of charge carriers and the band width given by Frhlich and Sewell, the sharp change of electrical conductivity of *** crystal during Peierls phase transition can be explained p

关键词： TTF CHANGE OF ENERGY BAND STRUCTURE DURING PEIERLS PHASE TRANSITION TCNQ

IONIC CONDUCTIVITY OF METHYLSILOXANE TERMINATED POLYETHYLENE OXIDE WITH LITHIUM PERCHLORATE NETWORK FILMS

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Chinese Journal of Polymer Science 1988年第4期6卷 332-336页

作者：李永军付英文方世璧江英彦 institute of chemistry Academia Sinica Academia Sinica Beijing

Complex films of crosslinked poly（methylsiloxane-co-ethylene oxide） and lithium perchlorate were prepared. These solid state polymeric electrolytes show a markedly higher ionic conductivity, and excellent flexibility. The ionic conductivity of the network films closed to 10-5 Scm-1 at room temperature. The effects of Li+ content, species and contents of crosslinking agents, molecular weight of poly（ethylene oxide） and temperature on the ionic conductivity of the network films were also investigated.

关键词： Poly (methylsiloxane-co-ethylene oxide) Polymeric solid electrolyte Network complex film

A Bidenate Amide Bonded Stationary Phase for HPLC

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Chinese Chemical Letters 2003年第8期14卷 820-823页

作者： Yan Shun MA Yuan De LONG Yong Liang DING Tian Bao HUANG Chengdu institute of Organic chemistry Chinese Academy of SciencesChengdu 610041

A novel bonded stationary phase, bidenate amide bonded stationary phase (BABSP), was prepared by reacting YWG silica gel firstly with 3-aminopropyltrimethoxysilane, then with diacid chloride. Hydrophobicity, selectivity, and especially silanophilic activity of BABSP were evaluated. The stationary phase exhibited good column efficiency and peak shape for separation of some basic solutes.

关键词： High performance liquid chromatography stationary phase silanophilic activity hydrophobicity.

Mangiferin,a natural xanthone,accelerates gastrointestinal transit in mice involving cholinergic mechanism

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World Journal of Gastroenterology 2012年第25期18卷 3207-3214页

作者： Talita Cavalcante Morais Synara Cavalcante Lopes Karine Maria Martins Bezerra Carvalho Bruno Rodrigues Arruda Francisco Thiago Correia de Souza Maria Teresa Salles Trevisan Vietla Satyanarayana Rao Flávia Almeida Santos Department of Physiology and Pharmacology Brazilian SemiArid Institute of BiomedicineFaculty of MedicineFederal University of CearáFortaleza 60430-270Brazil Post-Graduate Programme in Medical Sciences Faculty of MedicineFederal University of CearáFortaleza 60430-140Brazil Department of Organic and inorganic chemistry Federal University of CearáFortaleza 60451-970Brazil

AIM： To investigate the effects of mangiferin on gas- trointestinal transit （GIT） in normal and constipated mice, together with the possible ***： Intragastrically-administered charcoal mealwas used to measure GIT in overnight starved Swiss mice. In the first experiments, mangiferin （3 mg/kg, 10 mg/kg, 30 mg/kg, and 100 mg/kg, po） or tegaserod （1 mg/kg, ip） were administered 30 min before the char- coal meal to study their effects on normal transit. In the second series, mangiferin （30 mg/kg） was tested on delayed GIT induced by several different pharma- cological agonists （morphine, clonidine, capsaicin） or antagonists （ondansetron, verapamil, and atropine） whereas in the third series, mangiferin （30 mg/kg, 100 mg/kg and 300 mg/kg） or tegaserod （1 mg/kg） were tested on 6 h fecal pellets outputted by freely fed mice. The ratio of wet to dry weight was calculated and used as a marker of fecal water content. RESULTS： Mangiferin administered orally significantly （P 〈 0.05） accelerated GIT at 30 mg/kg and 100 mg/kg （89% and 93%, respectively）, similarly to 5-hydroxytrypta- mine4 （5-H%） agonist tegaserod （81%） when compared to vehicle-treated control （63%）. Co-administered man- giferin （30 mg/kg） totally reversed the inhibitory effect of opioid agonist morphine, 5-HT3-receptor antagonist ondansetron and transient receptor potential vanilloid-1 receptor agonist capsaicin on GIT, but only to a partial extent with the GIT-delay induced by ~2-adrenoceptor agonist clonidine, and calcium antagonist verapamil. However, co-administered atropine completely blocked the stimulant effect of mangiferin on GIT, suggesting the involvement of muscarinic acetylcholine receptor activation. Although mangiferin significantly enhanced the 6 h fecal output at higher doses （245.5±10.43 mg vs 161.9±10.82 mg and 227.1±20.11 mg vs 161.9±10.82 mg of vehicle-treated control, at 30 and 100 mg/ kg, P 〈 0.05, respectively）, the effect of tegaserod was more potent （297.4±7.42 mg vs 161.9±1

关键词： Mangiferin Glucosylxanthone Gastrointes-tinal transit Prokinetic action Cholinergic mechanism

Molecular modeling of rice Rubisco

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Chinese Journal of chemistry 1997年第4期15卷 353-360页

作者： Dai, WW Jiang, GF He, YN Xia, ZX Shanghai institute of Organic chemistry Chinese Academy of Sciences Shanghai 200032 China

Molecular model of rice Rubisco has been constructed by molecular modelling method on a computer graphics workstation using graphics software TOM-FRODO and QUANTA/CHARMm, based on the three-dimensional structure of spinach Rubisco. The molecular modelling was carried out in the following procedure: amino-acid sequence substitution; manual adjustment of the initial model; and energy minimization. The three-dimensional structure of the quaternary complex Rubisco CO2 . Mg2+. CABP of rice Rubisco has also been modelled and optimized using the program package XPLOR. The main-chain structure of rice Rubisco does not show obvious difference from that of spinach Rubisco, and the side-chains are located in the most favorable positions and orientations. The active-site structures are basically the same for the two species. The mutant Leu335-->Arg of rice Rubisco has been designed using the graphics software TURBO-FRODO and the program package XPLOR. Energy computation suggests that this mutation might increase the carboxylation activity.

关键词： rice Rubisco molecular modeling energy minimization mutant design

DELAYED FLUORESCENCE OF HYPOCRELLIN A AND ABSORPTION SPECTRA OF ISOMERS

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Chinese Science Bulletin 1989年第17期34卷 1442-1448页

作者：马俊宁蒋丽金张曼华虞群 institute of Photographic chemistry Academia Sinica Beijing

Hypocrellin A (abbreviated as HA )is not only an effective phototherapeutic agent, but also a good sensitizer. The absorption and fluorescence spectra of HA have been preliminarily investigated. Research on properties of the excited triplet state of HA has not yet been seen. In this note, the lifetime of phosphorescence was determined and the ex-

关键词： Hypocrellin A delayed fluorescence excited triplet state absorption spectrum

Synthesis and Characterization of Lanthanide Complexes Involving Cyclopentadienyl and Benzohydroximic Acid Ligand

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Journal of Rare Earths 2000年第4期18卷 315-317页

作者：王修然万玉保胡继萍 institute of Organic chemistry Anhui Normal University Wuhu 241000 China

By the reaction of Cp 3Ln with HL(Cp=η 5 C 5H 5, cyclopentadienyl; Ln=Yb, Tm, Er, Ho, Dy, Gd, Pr; HL=benzohydroximic acid), seven new complexes of the general formula Cp 2LnL were synthesized. All the complexes were characterized by elemental analysis, infrared spectra, and mass spectra. Based on these data, the probable structure was proposed.

关键词： rare earths benzohydroximic acid lanthanide complexes synthesis

Morphology of Branch Chain in Copolymer Surfactants on Interface

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Chinese Chemical Letters 1996年第10期7卷 948-950页

作者： Jian XU Liang He SHI Mei Ling YE(Polymer Physics Laboratory,institute of chemistry, Academia Sinica, Beijing 100080) Polymer Physics Laboratory Institute of Chemistry Academia Sinica Beijing 100080

The conformation of amphiphilic branch chain in acrylamide-poly(oxyethylene alkyl ether) acrylate copolymers on interface was investigated by static laser light scattering amid X-ray photoelectron spectroscopy. The re...

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Sterically Stabilized Poly(3, 4-ethylenedioxythiophene) Colloidal Dispersions Doped with Different Sulfonic Acids

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Chinese Chemical Letters 2006年第10期17卷 1391-1393页

作者： Tie Jun WANG Ping CHEN Xiu Jie HU Shu Yun ZHOU Technical institute of Physics and chemistry Chinese Academy of Science Beijing 100080

The preparation of sterically stabilized poly（3, 4-ethylenedioxythiophene）（PEDOT） colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesulfonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm^-1

关键词： PEDOT sulfonic acid colloidal particles polymeric stabilizer conductivity