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A Rapid Solid-phase Synthesis to Soluble Oligothiophene Molecular Wires

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Chinese Chemical Letters 2006年第4期17卷 437-440页

作者： hong ming ZHANG Xian hong wang Xiao Jiang ZHAO Ji LI Fo Song wang Polymer Material Engineering Lab Changchun Institute of Applied Chemistry CAS Changchun 130022

A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were ... 详细信息

关键词： Solid-phase synthesis molecular wires oligothiophene.

Secondary Structure Analysis of Native Cellulose by Molecular Dynamics Simulations with Coarse-Grained Model

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Chinese Journal of Chemical Physics 2012年第2期25卷 191-198,I0004页

作者： Shuai Wu Hai-yi Zhan hong-ming wang Yan Ju Institute for advanced study department of chemistryNanchang UniversityNanchang 330031China Nanchang Institute of Technology Nanchang UniversityNanchang 330031China

The secondary structure of different Iβ cellulose was analyzed by a molecular dynamics sim- ulation with MARTINI coarse-grained force field, where each chain of the cellulose includes 40 D-glucoses units. Calculation gives a satisfied description about the secondary structure of the cellulose. As the chain number increasing, the cellulose becomes the form of a helix, with the diameter of screw growing and spiral rising. Interestingly, the celluloses with chain number N of 4, 6, 24 and 36 do show right-hand twisting. On the contrast, the celluloses with N of 8, 12, 16 chains are left-hand twisting. These simulations indicate that the cellulose with chain number larger than 36 will break down to two parts. Besides, the result indicates that 36-chains cellulose model is the most stable among all models. Furthermore, the Lennard-Jones potential determines the secondary structure. In addition, an equation was set up to analyze the twisting structure.

关键词： Iβ cellulose Coarse-grained model Secondary structure Molecular dynamics

Synthesis and Unexpected Ring-opening Reaction of a New TADDOL Analogue with Chiral Cyclopropane Ring as Backbone

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Chinese Chemical Letters 2006年第5期17卷 606-608页

作者： Jun LIU Qing Hua BIAN ming An wang hong Chao GUO Min wang Department of Applied Chemistry China Agricultural University Beijing 100094

Synthesis and ring-opening reaction of TADDOL analogue with cyclopropane as chiral backbone were described. A plausible ring-opening and carbonium ion rearrangement mechanism have been proposed.

关键词： TADDOL analogue ring-opening cyclopropane ring synthesis. tetraaryl-1 3-dioxolane-4 5-dimethanol

Syntheses and Biological Activities of Ethyl N-Hydroxy-N-(substituted)phenyloxamates as KARI Inhibitors

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Chemical Research in Chinese Universities 2007年第3期23卷 280-283页

作者： wang Bao-lei LI Zheng-ming LI Yong-hong wang Su-hua Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Nine ethyl N-hydroxy-N-（substituted） phenyloxamates （2a-2i）, based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1^H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[ Ki values of （35.2±4.9） and （49.4 ±6. 3） μmol/L] having similar activity to the precursor of IpOHA（A, Ki =34. 1±6. 7 μmol/L）. The results will be helpful to further molecular design of more potent KARI inhibitors.

关键词： KARI inhibitor IpOHA Phenyloxamate Synthesis Biological activity

Effect of Boron Mud and CaF_2 on Surface Tension and Density of CaO-SiO_2-B_2O_3 Ternary Slag Systems

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Journal of Iron and Steel Research International 2014年第8期21卷 745-748页

作者： Li-li YANG hong-ming wang Xiang ZHU Gui-rong LI School of Materials Science and Engineering Jiangsu University Jiangsu Province Key Laboratory of High-End Structural Materials

The effect of boron mud and CaF2,which were used as fluxing agents,on surface tension and density of CaO-SiO2-B2O3 ternary slag systems was *** surface tension and density were measured by using the ring detachment method and Archimedean method,*** results indicated that surface tension and density of the slag systems decreased with increasing temperature in the range of 1380-1480℃.When 5%-10% CaF2 was employed as fluxing agent,the surface tension and density of slag were decreased with increasing CaF2 content,and the surface tension changed from 0.3to 0.6N/m,while the density changed from 3.4to 4.1g/***,when using 5%-10%boron mud as fluxing agent,the surface tension was enhanced,whereas the density decreased with the increase of boron mud content,and the variation range was 0.4-0.6N/m for surface tension and 3.2-3.9g/cm3 for the *** a conclusion,using boron mud as fluxing agent to substitute for CaF2 did not cause significant changes in slag surface tension and density.

关键词： boron mud calcium fluoride surface tension density

Microstructure and mechanical properties of AZ91 magnesium alloy subject to deep cryogenic treatments

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 896-901页

作者： Gui-rong Li hong-ming wang Yun Cai Yu-tao Zhao Jun-jie wang Simon P.A. Gill School of Materials Science & Engineering Jiangsu University The State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of Sciences Department of Engineering University of Leicester

AZ91 magnesium alloy was subjected to a deep cryogenic treatment. X-ray diffraction （XRD）, scanning electronic microscopy （SEM）, and transmission electronic microscopy （TEM） methods were utilized to characterize the composition and microstructure of the treated samples. The results show that after two cryogenic treatments, the quantity of the precipitate hardening β phase increases, and the sizes of the precipitates are refined from 8-10μm to 2-4μm. This is expected to be due to the decreased solubility of aluminum in the matrix at low temperature and the significant plastic deformation owing to internal differences in thermal contraction between phases and grains. The polycrystalline matrix is also noticeably refined, with the sizes of the subsequent nanocrystalline grains in the range of 50-100 nm. High density dislocations are observed to pile up at the grain boundaries, inducing the dynamic recrystallization of the microstructure, leading to the generation of a nanocrystalline grain structure. After two deep cryogenic treatments, the tensile strength and elongation are found to be substantially increased, rising from 243 MPa and 4.4% of as-cast state to 299 MPa and 5.1%.

关键词： magnesium alloys cryogenic treatment microstructure mechanical properties

DFT Study on Intermolecular Cleavage Reaction of N-(2-Hydroxyphenyl)-phthalamic Acid

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Chemical Research in Chinese Universities 2008年第6期24卷 790-792页

作者： ZHAO Chu-feng TANG ming-sheng wang hong-ming WEI Dong-hui ZHAO Jing ZHANG Shou-ren CAO Shu-xia Department of Chemistry Zhengzhou University Zhengzhou 450052 P. R. China

The reaction mechanisms of intermolecular cleavage reaction of N-（2-hydroxyphenyl）-phthalamic acid were studied via the density functional theory（DFT）. All geometries of the reactant, transition states, and products were optimized at the B3LYP/6-31G（d, p） level. Vibration analysis was carried out to confirm its identity as transitions＇ structure, and the intrinsic reaction coordinate method（IRC） was used to search the minimum energy path. Two possible reaction channels are reported in this article. The calculated results indicate that O-cyclization reaction channel has the lower activation barrier, and therefore, it occurs more easier than the other.

关键词： Intermolecular decomposition reaction Density functional theory(DFT) O-Cyclization N-Cyclization N-(2-Hydroxyphenyl)-phthalamic acid

Rolling With Simplified Stream Function Velocity and Strain Rate Vector Inner Product

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Journal of Iron and Steel Research International 2012年第3期19卷 20-24页

作者： ZHAO De-wen, ZHANG Shun-hu, LI Can-ming, SONG hong-yu, wang Guo-dong (State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, Liaoning, China) State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China

The dual-stream function velocity field is reduced in order to analyze two-dimensional plate broadside roll- ing in roughing. The strain rate vector inner product and integral mean value theorem, as well as coqine vector inner product are used respectively in plastic deformation power, friction losses and shear power. A theoretical solution of roll torque and separating force for the rolling is obtained and the calculated results by the solution are compared with those measured in broadside rolling on-line. It shows that both the force and torque calculated are higher than those of measured, but the maximum relative error between them is no more than 11%.

关键词： broadside roiling roll separating force strain rate vector inner product analytical solution

Influences of Refined Konjac Meal on the Levels of Tissue Lipids and the Absorption of Four Minerals in Rats

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Biomedical and Environmental Sciences 1990年第3期3卷 306-314页

作者： HOU YUN-HUA, ZHANG LI-SHI, ZHOU hong-ming, wang RUI-SHU, AND ZHANG YIN-ZHU School of Public Health, West China University of Medical Sciences, Chengdu,China School of Public Health West China University of Medical Sciences Chengdu.

This paper reports a study on the hypocholesterolemic effect of the refined konjac meal (RKM) containing about 80% glucomannan prepared from the tubers of Amorphophallus konjac *** and female Sprague-Dawley rats, 5 weeks old, were divided into five groups and fed a normal basal diet, a hypercholesterolemic diet (control diet), and three test diets (RKM added to the control diet at levels of 2.5.5, and 10%, respectively) for 12 *** results obtained indicate that RKM could markedly lower the cholesterol levels in the serum and the liver of rats eating hypercholesterolemic *** the end of the 4th week of the feeding experiment, the serum cholesterol levels in the 5 and the 10% RKM groups and the liver cholesterol level in the 10% RKM group were significantly lower than those in the control *** the end of the 12th week, the serum cholesterol levels of all the three RKM groups were lowered to a normal level as was the liver cholesterol level of the 10% RKM *** lipolropic effect of RKM was also confirmed by histopathologic examination of the *** addition to the hypocholesterolemic effects, RKM diets also increased stool *** effects on the absorption and utilization of Ca, Fe, Zn, and Cu were found. 1990 Academic ***.

关键词： RK Four