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Chinese Journal of Structural Chemistry 2007年第12期26卷 1429-1434页

作者：胡学雷邱立赵元弟key laboratory of biomedical Photonics of Ministry of Education - Wuhan National laboratory for Optoelectronics - Hubei bioinformatics and molecular imaging key laboratory - key laboratory of molecular biophysics of the Ministry of Education Huazhong University of Science and Technology 潘志权 key laboratory of biomedical Photonics of Ministry of Education - Wuhan National laboratory for Optoelectronics - Hubei bioinformatics and molecular imaging key laboratory - key laboratory of molecular biophysics of the Ministry of Education Huazhong University of Science and Technology Hubei key laboratory of Novel Chemical Reactor and Green Chemical Technology Wuhan Institute of Technology

The title compound （13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo-[23.***.1.1^11.15]- triaconta-l（29）,2,9,11,13,15（30）,16,23,25,27-decaene-29,30-diol-N^3,N^6,N^9,O^29,O^30）-bis（nitrato-O,O＇）- holmium（m） nitrate hydrate has been prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structures were determined by X-ray diffraction methods. The crystal crystallizes in the monoclinic system, space group C2/c with a = 23.737（12）, b = 14.237（7）, c = 19.801（10） A, β = 91.36（1）^o, Mr = 831.57, V = 6690（6） A^3, Z = 8, Dc = 1.651 g/cm^3, F（000） = 3344, R = 0.0482 and wR = 0.0923. The holmium ion is located in one of the compartments of the macrocyclic ligand and presents a distorted tricapped trigonal prismatic coordination geometry. The macrocycle is coordinated with two oxygen and three nitrogen atoms. Two nitrates are chelated in the opposite positions of the macrocycle, and the third one is ionic.

关键词： crystal structure lanthanide macrocycle

Metal-amyloid-β peptide interactions: a preliminary investigation of molecular mechanisms for Alzheimer’s disease

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Science China Chemistry 2007年第4期50卷 453-467页

作者： JIAO Yong & YANG Pin key laboratory of Chemical biology and molecular Engineering of Ministry of Education, Institute of molecular Science, Shanxi University, Taiyuan 030006, China key laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan China

Although humans have spent exactly 100 years combating Alzheimer’s disease (AD), the molecular mechanisms of AD remain unclear. Owing to the rapid growth of the oldest age groups of the popula-tion and the continuous increase of the incidence of AD, it has become one of the crucial problems to modern sciences. It would be impossible to prevent or reverse AD at the root without elucidating its molecular mechanisms. From the point of view of metal-amyloid-β peptide (Aβ) interactions, we review the molecular mechanisms of AD, mainly including Cu2+ and Zn2+ inducing the aggregation of Aβ, cata-lysing the production of active oxygen species from Aβ, as well as interacting with the ion-channel-like structures of Aβ. Moreover, the development of therapeutic drugs on the basis of metal-Aβ interactions is also briefly introduced. With the increasingly rapid progress of the molecular mechanisms of AD, we are now entering a new dawn that promises the delivery of revolutionary developments for the control of dementias.

关键词： Alzheimer’s disease (AD) amyloid-β peptide Cu2+ Zn2+ molecular mechanisms aggregation active oxygen species ion channel

A scheme to implement the Deutsch-Josza algorithm on a superconducting charge-qubit quantum computer

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Progress in Natural Science:Materials International 2006年第6期16卷 594-599页

作者： HUO Wenyi and LONG Guilu (key laboratory for Quantum Information and Measurements, and Department of Physics, Tsinghua University, beijing 100084, China key laboratory for Atomic and molecular NanoSciences, Tsinghua University, beijing 100084, China) key laboratory for Quantum Information and Measurements and Department of Physics Tsinghua University Beijing 100084 China key laboratory for Atomic and molecular NanoSciences Tsinghua University Beijing 100084 China

We have studied the implementation of the Deutsch-Josza quantum algorithm in a superconducting charge-qubit quantum computer. Different from previous studies, we have used the inductance coupled system of You et al. The detailed pulse sequences have been designed for the four possible functions in a 2-qubit system. The result is generalized to an arbitrary n-qubit system. This scheme will be useful for practical implementation of the algorithm.

关键词： superconducting quantum computer Deutsch-Josza algorithm.

Effects of La^(3+) and Eu^(3+) on outward potassium channels in Vicia guard cells

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Science China Chemistry 2009年第11期52卷 1821-1824页

作者： XUE ShaoWu & YANG Pin key laboratory of Chemical biology and molecular Engineering of Ministry of Education,Institute of molecular Science,Shanxi University,Taiyuan 030006,China key laboratory of Chemical biology and molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan China

Effects of La3+ and Eu3+ on outward potassium channels(K+out) in Vicia guard cells have been studied by patch clamping *** La3+ inhibited K+out currents with a half-inhibition concentration(IC50) of 81 μmol·***,intracellular La3+ activated K+out currents at a free concentration of 1.13 × 10-14 mol·L-1,and inhibited K+out currents at a free concentration of 5.86 × 10-14 mol·*** Eu3+ also activated K+out currents at concentrations of 10 μmol·L-1 and 50 μmol·L-1,and inhibited K+out currents at concentrations of more than 1 mmol·*** effects of La3+ and Eu3+ on K+out currents may contribute to regulation of the plant water status,which may be one of the mechanisms of the biological effect of rare earth elements.

关键词： rare earth elements stomata guard cell outward potassium channel

SILICA-SUPPORTED NICKEL AND ZIRCONIUM CATALYSTS FOR bRANCHED POLYETHYLENE

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Chinese Journal of Polymer Science 2003年第4期21卷 453-458页

作者：孙文华 State key laboratory of Engineering Plastics The Center for molecular Sciences Institute of Chemistry Chinese Academy of Sciences beijing 100080 China State key laboratory of Engineering Plastics The Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

8-Aminoquinoline nickel dichloride and bis(cyclopentadienyl)zirconium dichloride (Cp_2ZrCl_2) were supportedsimultaneously on silica to produce branched polyethylene successfully by combined polymerization. The supportedpolymerization results showed that the molecular weight of polyethylene increased while the molecular weight distributionbecame wider and the molecular chains of oligomers remaning in the final solution became shorter as compared to theoligomers obtained in polymerization processes with pure 8-aminoquinoline nickel dichloride catalysis, as well as theCp_2ZrCl_2 and nickel combination system. With decreasing amount of Ni catalyst in the supported catalyst, the molecular chains of oligomers in the resulting solution became shorter, while α-olefin selectivity increased.

关键词： 8-Aminoquinoline nickel dichloride, Cp_2ZrCl_2 Silica supported catalysts branched polyethylene

Magnetism induced by nonmagnetic dopants in zinc-blende SiC: First-principle calculations

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 1-10页

作者： LIU ZhaoQing & NI Jun Department of Physics and key laboratory of Atomic and molecular Nanoscience (Ministry of Education), Tsinghua University, beijing 100084, China Tsinghua University Department of Physics and Key Laboratory of Atomic and Molecular Nanoscience (Ministry of Education) Beijing China (GRID:grid.12527.33) (ISNI:***)

Magnetism induced by the nonmagnetic dopants in the zinc-blende SiC (3C-SiC) is investigated by first-principle calculations. The atoms of the first 20 elements in the periodic table except inert gas are used to replace either Si or C atoms as dopants. We find that some nonmagnetic substitutional dopants (mainly the Group IA, Group IIA, Group IIIb, and Group VIIb elements) prefer the spin-polarized ground states with local magnetic moments. In general, the condition for obtaining the local magnetic moments and the magnetic ground state requires that the dopants are p-type and have large electronegativity difference from the neighboring host atoms. The magnetic moments can be tuned over a range between 1 μ b and 3 μ b by doping with the nonmagnetic elements. The nearest-neighbor exchange couplings J 0 between the local magnetic moments are quite large and the codoping method is proposed to increase the dopant concentration. These imply that the nonmagnetic doping in SiC may exhibit collective magnetism. Moreover, the Group IIA Mg and Ca atoms substituting the preferred Si atoms favor the ferromagnetic ground states with the half-metallic electronic properties, which suggests that Mg or Ca substitutional doping on the Si sites in SiC could be a potential route to fabricating the diluted magnetic semiconductors.

关键词： nonmagnetic dopant magnetism SiC diluted magnetic semiconductor first-principle calculation

The design and synthesis of fused thiophenes and their applications in organic field-effect transistors

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Science China Chemistry 2010年第4期53卷 779-791页

作者： LIU Ying, YU Gui & LIU YunQi beijing National laboratory for molecular Sciences, key laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, beijing 100190, China beijing National laboratory for molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing China

Fused thiophenes refer to oligothienoacenes in which several thiophenes are coupled together via twoor multi-positions and their derivatives. The synthesized organic semiconductors based on fused thiophenes exhibit excellent field effect properties due to their efficient intermolecular S…S interactions and π…π stacking. The performances of organic field-effect transistors (OFETs) depend not only on the materials but also on the devices. Such factors which influence the device performances as device structures, fabrication technologies and interface engineering are extensively investigated based on the fused thiophenes. Searching for new organic semiconductors and improving the device fabrication technologies are two major issues in the development of OFETs.

关键词： fused thiophenes oligothienoacenes organic field-effect transistors device performance

High-resolution photofragment translational spectro- scopy for the UV photodissociation of C_2H_5I

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Science China Chemistry 2007年第4期50卷 476-482页

作者： bI Weibin, XU XiLing, HUANG JianGou, XIAO DaoQing & ZHU QiHe beijing National laboratory for molecular Sciences, State key laboratory of molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, China beijing National laboratory for molecular Sciences State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The photodissociation of ethyl iodide at 279.71, 281.73, 304.02 and 304.67 nm has been studied on our new mini-photofragment translational spectrometer with a total flight path of only 5 cm. Some vibra-tional peaks are firstly resolved in the TOF spectra of I*(2P1/2) and I(2P3/2) channels. These vibrational peaks are assigned to the excitation states (ν2 = 0, 1, 2,…) of the umbrella mode (ν2, 540 cm-1) of the photofragment C2H5, and the distribution of the vibrational states is obtained. The dissociation energy has been determined to be D0(C-I)=2.314 ± 0.03 eV. The energy partitioning of the available energy (Eavl=ET+Eint=ET+EV,R) calculated from our experimental data E int /E avl= 22.1% at 281.73 nm, 22.4% at 304.02 nm for the I* channel, and E int /E avl= 25.2% at 279.71 nm, 25.9% at 304.67 nm for the I channel, seem to be more reliable.

关键词： photofragment translational spectroscopy C_2H_5I photodissociation vibrational state distribution energy partitioning dissociation energy

Dynamic Monte Carlo simulation of chain growth polymerization and its concentration effect

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Science China Chemistry 2005年第5期48卷 459-465页

作者： Lü Wenqi & DING Jiandong key laboratory of molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China key laboratory of molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai China

Free radical polymerization and living ion polymerization have been simulated via the dynamic Monte Carlo method with the bond-fluctuation model in this paper. The polymeriza-tion-related parameters such as conversion of monomers, degree of polymerization, average molecular weight and its distribution are obtained by statistics. The simulation outputs are con-sistent with the corresponding theoretical predictions. The scaling relationships of the coil size versus chain length are also confirmed at different volume fractions. Furthermore, the effect of diffusion on polymerization is revealed preliminarily in our simulation. Hence the simulation ap-proach has been proven to be feasible to investigate polymerization reactions with the advan-tages that configuration and diffusion of polymer chains can be examined together with polym-erization kinetics.

关键词： living ion polymerization free radical polymerization concentration effect configuration Monte Carlo simulation.