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Study of association of alcohols in aprotic solvents by multinuclear NMR

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chinese Journal of Chemistry 1993年第4期11卷 299-307页

作者： YAN,Xian-Zhong XUE,Yi DU,You-Ru state key {2. of magnetic resonance and atomic and molecular Physics,wuhan institute of Physics,chinese academy of sciences,wuhan 430071 state key {2. of Mognetto resonance and atomic and molecular Physics Wuhan Institute of Physics Chinese Academy of Sciences Wuhan 430071

Binary mixtures of alcohols(ethyl,n-butyl and n-amyl)with several aprotic sol- vents,such as acetone,dioxane,THF,DMSO and DMF have been studied systematically by ~1H,^(13)C,^(15)N and ^(17)O NMR *** concentration dependence of chemical shift of the solvent was used to evaluate equilibrium constants of the complexation of alcohols with the solvents.A relationship between the proton shift of alcohol uncombined with the solvent and its concentration was found,and the fraction of unassociated hydroxyl groups was thus quantitatively *** effect of solvent on self association and complexation of the alcohol is discussed on the basis of the electron donicity of the solvents.

关键词： vent Study of association of alcohols in aprotic solvents by multinuclear NMR

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary laboratory, Zhejiang University, Hangzhou 310027,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, wuhan 430030, china 2institute of High Energy Physics and key laboratory of Nuclear Analysis Techniques, chinese academy of sciences, P.O. Box 918, Beijing 100039, china 3wuhan institute of Physics and mathematics, state key laboratory of magnetic resonance and atomic and molecular Physics, chinese academy of sciences, wuhan 430071, china Department of Physics and Bio-X disciplinary laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China wuhan institute of Physics and {2. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of High Energy Physics and key {2. of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2. signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2. signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser2.2.was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2. An AD-like spatial memory retention disturbance was induced at 2. h after isoproterenol injection. (3) A sensitivity threshold of resting T2. signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2. signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

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chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2. WEI ZhengRong1,2. CAO ZhenZhou1,2. ZHANG ChangHua1,2.& ZHANG Bing1,2.1 state key {2. of magnetic resonance and atomic and molecular Physics, wuhan institute of Physics and mathematics, chinese academy of sciences, wuhan 430071, {12. 2.Graduate University of chinese academy of sciences, Beijing 100039, {12. state key {2. of magnetic resonance and atomic and molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Graduate University of chinese academy of sciences Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2.rCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2.rCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2.l^+ and CH_2.r^+) and the parent ion (CH_2.rCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2.l^+ and CH_2.r^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2., respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

Quantum states of neutral atoms bound in the magnetic field of a Kepler-guide

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原子与分子物理学报 2003年第3期20卷 369-372页

作者： HE Ming, WANG Jin, ZHAN Ming sheng (state key {2. of magnetic resonance and atomic and molecular Physics, wuhan institute of Physics and mathematics, chinese academy of sciences, wuhan 430071, P.R.{12.) wuhan institute of Physics and {2. Chinese Academy of Sciences State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics CAS Wuhan 430071

The spectrum and the wave function of neutral atoms in the magnetic field of a Kepler guide are presented by reducing a two dimensional stationary Schrdinger equation to a one dimensional hydrogen atom in Rydberg states. In addition, we set the scale for the {2. orbits and binding energy in the quantum regime, and compare it with the outcome of the experiment. At the same time, we find that reducing the current and radius of the wire properly will increase the loading efficiency of the Kepler guide.

关键词：量子态中性原子开普勒波导磁性

Spectral decomposition at a complex laser polarization configuration

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chinese Physics B 2013年第5期22卷 263-266页

作者：杨海峰高伟成红刘红平 state key {2. of magnetic resonance and atomic and molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences

We study the role of laser polarization in the diamagnetic spectrum for the transition from the ground state to the highly excited Rydberg states through a single photon absorption. For simplicity, one usually polarizes the irradiation laser to the selected main quantum axis, which is along the applied external electric or magnetic field. The transition selection rule is simply expressed as Am = O, which corresponds to the π transition. When the polarization is circularly polarized around the main axis, the σ＋ or σ- transition occurs, corresponding to the selection rule of △m = 1 or △m = - 1, respectively. A slightly more complex case is that the laser is linearly polarized perpendicular to the main axis. The numerical calculation shows that we can decompose the transition into the sum of σ＋ and σ- transitions, it is noted as the σ transition. For the more complex case in which the laser is linearly polarized with an arbitrary angle with respect to the main axis, we have to decompose the polarization into one along the main axis and the other one perpendicular to the main axis. They correspond to π and σ transitions, respectively. We demonstrate that these transitions in the diamagnetic spectrum and the above spectral decomposition well explain the experimentally observed spectra.

关键词： diamagnetic spectrum Rydberg atoms laser polarization

A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2.,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2.,ZENG Bin 1,2.,CHU Wei 1,2.,CHENG Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 state key {2. of High Field Laser Physics,Shanghai institute of Optics and Fine Mechanics,chinese academy of sciences,Shanghai 2.1800,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3 state key {2. of magnetic {12. and atomic and molecular Physics,wuhan institute of Physics and mathematics,chinese academy of sciences,wuhan 430071,china 4 institute of Applied Physics and Computational mathematics,Beijing 100088,china 5 Center for Applied Physics and Technology,Peking University,Beijing 100084,china state key {2. of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China Graduate University of chinese academy of sciences Beijing China state key {2. of magnetic resonance and atomic and molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China institute of Applied Physics and Computational mathematics Beijing China Center for Applied Physics and Technology Peking University Beijing China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

Preparation And Characterization of a New Blend of Poly(2.hydroxyethyl methacrylate) And Poly(ethylene glycol)

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chinese Chemical Letters 1997年第11期8卷 953-956页

作者： Wei Bin CHEN Han Qiao FENG Da Yong HE Chao Hui YE(laboratory of magnetic {2. and atomic and molecular Physics, wuhan institute of Physics and mathematics, chinese academy of sciences, wuhan 430071.)(Polymer Physics laboratory, Changchun institute Lab. magnetic Reson./Atom./Molec. P. Wuhan Inst. of Phys. and Mathematics Chinese Academy of Sciences Wuhan 430071 China Polymer Physics laboratory Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

A new blend of poly(2.hydroxyethyl methacrylate) (PHEMA) with poly (ethylene glycol) (PEG) was prepared. The results from solid-state NMR indicate that the PHEMA/PEG(88:12. w/w) blend is miscible on a molecular level.

关键词： PHEMA Preparation And Characterization of a New Blend of Poly ethylene glycol hydroxyethyl methacrylate Blend

Experimental and theoretical study of^(13)C shielding tensors in new-style molybdenum complex

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Science china Chemistry 2004年第3期47卷 214-221页

作者： HOU Guangjin1,2. WANG Liying2. LU Xiaoming3, ZHENG Anmin2. DENG Feng2.&YE Chaohui1,2.1. Department of Physics, Huazhong University of Science and Technology, wuhan 430074, china 2. {2. key laboratory of magnetic resonance and atomic and molecular Physics, wuhan institute of Physics and mathematics, Chi-nese {12. of sciences, wuhan 430071, china 3. Department of Chemistry, Capital Normal University, Beijing 100037, china Department of Physics Huazhong University of Science and Technology Wuhan China chinese academy of sciences Wuhan China Department of Chemistry Capital Normal University Beijing China

13C 2.-PASS spectra of two new cis-dioxo catecholatomolybdenum complexes (NH2.H2.H2.HCH2.2.H+)3[MovO 2.C6H4O2.2. and (NH2.H2.H2.H2.H2.2.H+)3[Mo(v)O2.(C2.2.2.2. have been obtained by solid-state nuclear magnetic {2. (NMR), in which the spinning sidebands were well-separated. The principal components of the 13C shielding tensors were extracted by theoretically fitting the intensities of 13C spinning sidebands. The effects of counter cations on 13C chemical shift isotropy and shielding tensor of cis-dioxo catecholatomolybdenum complex anion [Mo (v)O2.C6H4O2.2.3? were studied, comparing the 13C CSA of those carbon sites in complex anions with that of the counter cations. Based on the known structure of the molybdenum complex crystal, theoretical values of 13C shielding tensors were calculated by the ainitio GIAO method, in comparison with the experimental results.

关键词： NMR, magic angle spinning, chemical shift anisotropy, shielding tensor, cis-dioxo-monomolybdenum.

NON-ADIABATIC DYNAMICS IN POLYatomic MOLECULES BY FEMTOSECOND PHOTOELECTRON IMAGGING

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NON-ADIABATIC DYNAMICS IN POLYATOMIC MOLECULES BY FEMTOSECON...