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Erythrocentaurin, Biosynthesis Postulation and Biomimetic Synthesis

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有机化学 2004年第Z1期24卷 300-301页

作者： LEI,Jun YUAN,Xiang-Hui LIU,Zhu-Lan LIU,Jian-Li Department of Chinese Material Medica Northwest University Xi''an 710069 Department of Chinese Material Medica Northwest University Xi''an 710069 Department of Chinese Material Medica Northwest University Xi''an 710069 Department of Chinese Material Medica Northwest University Xi''an 710069

　　Erythrocentaurin is a relatively simple nature product isolated from the root of Gentiana macrophylla Pall.[1] The co-existed of gentiopicroside from the same species led to speculation that erythrocentaurin is a biosynthesis product of gentiopicroside. The transformation of secologanin to carbocyclic aglycone under biomimetic condition has already known (Scheme 1).[2,3] The postulated biosynthesis pathway of erythrocentaurin may be in the same way. In the process the cyclic hemiacetal of the aglycone opened to the dialdehyde which then undergoes a vinylogous aldol reaction, and then dehydroxylation and double bond migration to the title compound (Scheme 2).……

关键词： aldol reaction double bond

Relationship Between the mRNA Expression Level of TGF-β Receptor Genes in Tissues and Ovulation Rate in Hu Sheep

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Agricultural sciences in China 2010年第11期9卷 1659-1666页

作者： LI Er-lin XIE Xin-hua XU Ye-fen XIE Zhuang CHEN Ling LIU Hong-lin LI Qi-fa College of Animal science and Technology Nanjing Agricultural University Nanjing 210095 P.R. China Breeding Sheep Farm of Hu Sheep Stock Seed Farm Suzhou 215200 P.R.China

Eight ewes of Hu sheep which bred multi-lamb were used as the high-fecundity group and the other eight ewes of Hu sheep which bred single lamb were used as the control group to investigate the relationship between the mRNA expression level of TGF-β receptor genes in tissues and ovulation rate in Hu sheep. Cloprostenol sodium was injected to make the synchronization of estrus treatment, then all ewes were slaughtered within 24-36 h after empathema and the ovaries were collected. Furthermore, the number of ovulation points was counted to determine ovulation rate for each sheep. Tissue expression analysis was conducted by RT-PCR for one ewe form the high-fecundity group and the relationship between the mRNA expression of genes encoding TGF-β receptors and ovulation rate was detected by real-time fluorescent quantitative PCR. The results showed that the relative expression level of TGF-flR I gene in the reproductive organ was significantly higher than in the lung and muscle （P 〈 0.01）, while relative expression level of TGF-βR H in reproductive organ was significantly higher than that of other tissues （P 〈 0.01）, indicating that these are highly expressed genes in the ovary. In addition, mRNA expression level of TGF-βR I and TGF-flRH in the ovaries of the high-fecundity group were significantly higher （P〈 0.01） and obviously higher （P= 0.011） than the control group, respectively. The mRNA expression level of TGF-βR I and TGF-βR H had a positive correlation with ovulation rate and the correlation coefficients were 0.562 （P〉 0.05） and 0.711 （P〈 0.05）, respectively. It is suggested that TGF-β receptors have close relationship with highfecundity in Hu sheep.

关键词： Hu sheep TGF-βR I TGF-βR H ovulation rate

Adsorption Activity and Molecular Dynamics Study on Anti-corrosion Mechanism of Q235 Steel

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Chemical Research in Chinese Universities 2018年第5期34卷 817-822页

作者： ZHANG Weiwei LI Huijing WU Yanchao LUO Qi LIU Huanhuan NIU Lin School of Marine science and Technology Harbin Institute of Technology Weihai 264209 P. R. China School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China

The correlation between inhibition efficiency and molecular structures of the inhibitor during hydrochloric acid corrosion of Q235 steel was studied by quantum chemical calculations and molecular dynamics（MD） simulation. The proton affmity（PA） calculations demonstrated that 2-（quinolin-2-yl）quinazolin4（3H）-one inhibitor has the ten- dency to be protonated in hydrochloric acid, which was in good agreement with experimental observations. Besides, quantum chemical parameters revealed that the protonated corrosion inhibitor molecules were more easily adsorbed on Q235 steel surface and improved the corrosion resistance of steel. MD simulations were implemented to search for the adsorption behavior of this molecule on Fe （110） surface, which might be used as a convenient tool for estimating the interaction mechanism between inhibitor and iron surface.

关键词： Q235 steel Corrosion inhibition Density functional theory Molecular dynamic simulation

p-Nitrophenyl Picolinate Cleavage by Unsymmetrical Bis-Schiff Base Manganese（Ⅲ） and Cobalt（Ⅱ） Complexes with Aza-Crown Ether or Morpholino Pendants

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Chinese Journal of Chemistry 2011年第9期29卷 1894-1900页

作者： Li, Jianzhang He, Xiyang Wang, Ying Zhang, Jin Hu, Wei Qin, Shengying Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan School of Chemistry and Pharma- ceutical Engineering Sichuan University of Science ＆ Engineering Zigong Sichuan 643000 China Department of Chemistry and Environment science Chongqing University of Arts and Science Yongchuan Chongqing 402160 China Department of Chemistry Sichuan University Chengdu Sichuan 610064 China

The unsymmetrical bis-Schiff base manganese（III） and cobalt（II） complexes with either benzo-10-aza-crown ether pendants （MnL1Cl, MnLZCl） or morpholino pendant （MnL3Cl, CoL3） have been employed as models for hy- drolase by studying the kinetics of their hydrolysis reactions with p-nitrophenyl picolinate （PNPP）. A kinetic model of PNPP cleavage catalyzed by these complexes is proposed. The effects of complex structures and reaction temperature on the rate of PNPP hydrolysis have been examined. All four complexes exhibit high catalytic activity and the rate increases with pH under 25℃. The complexes of ligands containing a crown ether group exhibit higher catalytic activities than the non-crown analogues. The catalytic activity of the complexes follows the order Mn（III）〉 Co（II） under the same ligands.

关键词： benzo-10-aza-crown ether unsymmetrical bis-Schiff base complexes hydrolysis p-nitrophenyl pi-colinate kinetics

Radiative forcing and global warming potential of perfluorocarbons and sulfur hexafluoride

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science China Earth sciences 2011年第5期54卷 764-772页

作者： ZHANG Hua WU JinXiu SHEN ZhongPing Laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing 100081 China Shanghai Meteorological Media Center Shanghai 200030 China Shanghai Climate Center Shanghai 200030 China

We developed two radiation parameterizations with different resolutions(17-band and 998-band) for perfluorocarbons(PFCs) and sulfur hexafluoride(SF6) using the updated High-resolution Transmission Molecular Absorption(HITRAN) 2004 database and the correlated k-distribution *** analyzed the impacts of the two radiation schemes on heating *** we studied their instantaneous radiative efficiency,stratospheric adjusted radiative efficiency,global warming potential(GWP),and global temperature potential(GTP),for both clear-and all-sky conditions using a high-resolution radiation *** found that the stratosphere-adjusted radiative efficiencies of C2F6,CF4,and SF6 for the whole sky were 0.346,0.098,and 0.680 W m-2 ppbv-1,*** forcing from the industrial revolution to 2005 was 0.001,0.007,and 0.004 W m-2,re-spectively;and was predicted to rise to 0.008,0.036,and 0.037 W m-2,respectively,by 2100,according to emission scenarios provided by the *** GWPs of C2F6,CF4,and SF6 are 17035,7597,and 31298,respectively,for a time horizon of 100 years relative to *** GTPs of pulse and sustained emissions,GTPP and GTPS,are 22468,10052,and 40935 and 16498,7355,and 30341,respectively,for a 100-year time horizon.

关键词：辐射强迫六氟化硫四氟化碳全球变暖辐射效率时间跨度绿茶多酚辐射参数化

Quantum Mechanical Nature in Liquid NMR Quantum Computing

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Communications in Theoretical Physics 2002年第3期38卷 305-308页

作者： LONG Gui-Lu YAN Hai-Yang LI Yan-Song TU Chang-Cun ZHU Sheng-Jiang RUAN Dong SUN Yang TAO Jia-Xun CHEN Hao-Ming Department of Physics Tsinghua University Beijing 100084 China Laboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Center for Atomic and Molecular Nano-sciences Tsinghua University Beijing 100084 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Laboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA Department of Chemistry Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China

The quantum nature of bulk ensemble NMR quantum computing the center of recent heated debate,is addressed. Concepts of the mixed state and entanglement are examined, and the data in a two-qubit liquid NMRquantum computation are analyzed. The main points in this paper are: i) Density matrix describes the "state" of anaverage particle in an ensemble. It does not describe the state of an individual particle in an ensemble; ii) Entanglementis a property of the wave function of a microscopic particle (such as a molecule in a liquid NMR sample), and separabilityof the density matrix cannot be used to measure the entanglement of mixed ensemble; iii) The state evolution in bulk-ensemble NMRquantum computation is quantum-mechanical; iv) The coefficient before the effective pure state densitymatrix, e, is a measure of the simultaneity of the molecules in an ensemble. It reflects the intensity of the NMR signaland has no significance in quantifying the entanglement in the bulk ensemble NMR system. The decomposition of thedensity matrix into product states is only an indication that the ensemble can be prepared by an ensemble with theparticles unentangled. We conclude that effective-pure-state NMR quantum computation is genuine, not just classicalsimulations.

关键词： quantum mechanical nature, NMR quantum computing, mixed state, entanglement

Room-temperature ligancy engineering of perovskite electrocatalyst for enhanced electrochemical water oxidation

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Nano Research 2019年第9期12卷 2296-2301页

作者： Junchi Wu Yuqiao Guo Haifeng Liu Jiyin Zhao Haodong Zhou Wangsheng Chu Changzheng Wu Hefei national Laboratory for Physical sciences at the Microscale Collaborative Innovation Center of Chemistry far Energy Materials (iChEM)and CAS Key Laboratory of Mechanical Behavior and Design of MaterialsUniversity of Science and Technology of ChinaHefei 230026China national Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Analytical and Testing Center Southwest University of Science and TechnologyMianyang 621010China

Perovskite oxides are significant candidates to develop electrochemical catalysts for water oxidation in consideration of their high catalysis capacity,low costing and excellent *** design of coordination structure and overcoming poor electronic transport are regarded as critical factors for outstanding perovskite-based oxygen evolution reaction (OER) ***,we report a mild chemical oxidation method to realize ligancy engineering from strongly-correlated brownmillerite Sr2Co2O5 to perovskite phase Sr2Co2O5.5,along with abundant oxygen vacancies formation and greatly boosted electric conductivity,which helps to form the active species of Co hydroxide/oxide on the surface of *** coupling effect of catalytic kinetics and unimpeded electronic movement brings high OER activities in Sr2Co2O5.5 with a low onset potential and a small Tafel *** work not only displays in-depth understanding into the relationship among catalysis performance and multiple physical degrees of freedom,but also paves a new path to develop high-efficient electrochemical catalysts.

关键词： perovskite oxides ligancy engineering oxygen evolution reaction electrocatalysts