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Investigation of Mechanism of Co-doped Zn^(2+) and In^(3+) Influence on Optical Properties of Fe∶LiNbO_3

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High Technology Letters 2001年第2期7卷 92-94页

作者：王锐 dept. of Applied chemistry Electro Optics Research Center Harbin Inst. of Technology Harbin 150001 China

Doping Zn with the concentration of 3mol% and In 2O 3 with different concentrations in Fe∶LiNbO 3, Zn∶In∶ Fe∶ LiNbO 3 crystals were grown. The infrared spectra of the crystals were measured and the mechanism of the OH-, absorption peak shifting was studied. The diffraction efficiency, response time and photoconduction of the crystals were measured. The mechanisms of the photoconduction increasing, diffraction efficiency decreasing and response time shorting for those crystals were studied.

关键词： Zn∶In∶Fe∶LiNbO 3 crystal Optical property Infrared spectra

WA, a new Antifungal Antibiotic from a Soil Fungus Strain 38

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Chinese Chemical Letters 1998年第6期9卷 539-540页

作者： Jun YANG Xiu Lan QI Wen LI Gang SHAO Xin Sheng YAO S. KITANAKA(Department of Natural Medicinal chemistry, Shenyang Pharmaceutical University, Shenyang 110015)(Department of Pharmacognosy, College of Pharmacy, Nihon University, Japan) dept. of Natural Medicinal chemistry Shenyang Pharmaceutical University Shenyang 110015 China Department of Pharmacognosy College of Pharmacy Nihon University Japan

A new antifungal antibiotics, WA, was isolated from the secondary metabolites of soil fungus strain 38, and its structure was elucidated as 4-(2-hydroxy-3-butynoxy)benzoic acid by means of the spectral data (H-1-and C... 详细信息

关键词： WA structure elucidation activity against P-oryzae

The Synthesis of a Novel Lignan

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Chinese Chemical Letters 2000年第11期11卷 971-974页

作者： Qi X.X. Chang J.B. Guo R.Y. Chen R.F. Chem. dept. of Zhengzhou Univeristy Zhengzhou 450052 China Henan Institute of chemistry Henan Academy Sciences Zhengzhou 450002 China

A short convenient synthesis of a novel lignan, 2-(3′,4′,5′-trimethyoxyphenyl)-1,3-dimethyl-6,7,8-trimethoxy- naphthalene has been accomplished by the condensation of key intermediates, 3,4,5-trimethoxybenzyl methy... 详细信息

关键词： UV KBr IR The Synthesis of a Novel Lignan EtOH

Novel Antifungal Antibiotic, WB Produced by the Fungus Strain 38

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Chinese Chemical Letters 1998年第9期9卷 833-834页

作者： Jun YANG Xiu Lan QI Gang SHAO Yue Hu PEI Xin Sheng YAO (Department of Natural Medicinal chemistry, Shenyang Pharmaceutical University Shenyang 110015)Susumu KITANAKA (Department of Pharmacognosy, College of Pharmacy, Nihon University, Japan) dept. of Natural Medicinal chemistry Shenyang Pharmaceutical University Shenyang 110015 China Department of Pharmacognosy College of Pharmacy Nihon University Japan

WE, a new antifungal antibiotic, was isolated from the soil fungus strain 38 against Pyricularia oryzae, and its structure was elucidated as 2-[(E)-3,5-dimethyl-3,4-dihydroxy-1-eptylenyl]-4-chloro-5-oxo-6-methyl-6,7-d... 详细信息

关键词： antifungal antibiotic WB structure elucidation

Using GC to determinate polychlorinated biphenyls in soil after pretreated with microwave-assisted alkaline degradation method

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Journal of Harbin Institute of Technology(New Series) 2006年第5期13卷 549-553页

作者：何小青李攻科罗美中张展霞 Shenzhen Academy of Metrology and Quality Inspection Shenzhen 518055 China dept. of chemistry Zhongshan University Guangzhou 510275 China

A new and simple microwave-assisted alkaline degradation (MAAD) method for the elimination of organochlorine-pesticide interference on the determination of polychlorinated biphenyls (PCBs) in soil by GC is presented. Under the optimal conditions, the interference of α-HCH, β-HCH, γ-HCH, δ-HCH, o.p’-DDT, p.p’-DDD and p.p’-DDT could be eliminated completely, and p.p’-DDE, Aldrin and Dieldrin could be partially eliminated; however, Dieldrin could be completely eliminated by using concentrated sulphuric acid. The method was evaluated by analyzing the spiked-soil sample. The mean recovery obtained was 84.1% and the Relative Standard Deviation (RSD) was 2.7%. Experimental results also indicate that the degradation of the interference and the extraction of the target analytes, PCBs, could be carried out simultaneously. Compared with the traditional methods, the MAAD method is a rapid, efficient and solvent-saving method.

关键词：碱降解微波 MAAD PCBs 有机机体机化气相色谱分析土壤

New autocorrelation topological indexes and their application in QSAR study

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Journal of Harbin Institute of Technology(New Series) 2005年第1期12卷 41-43页

作者：王鹏杨蕾陈春云高大文龙明策 Center of Green chemistry and Technology School of Municipal and Environment Harbin Institute of Technology Harbin 150001 China dept. of Applied chemistry Harbin Institute of Technology Harbin 150001 China

Considering the problems of classical structure parameters that existed in the study of quantitative structure activity relationship (QSAR). Two new groups of autocorrelation topological indexes V(t), E(t), (P(t)) and A(t), B(t), C(t), D(t) were developed on the basis of molecular topology and autocorrelation function in mathematics. The first group were obtained from Van der Waals volume, electronegativity and topological vertex degree;and the second group were obtained from the different combination of topological vertex *** softwares of ATIJP and ATITP have been developed for calculating these two new groups of indexes. Better results have been obtained from the application of these indexes in QSAR study.

关键词：有机化合物逻辑拓扑结构 QSAR 数量结构活性关系数学模拟技术

SYNTHESIS AND CHARACTERIZATION OF MAIN CHAIN AROMATIC LIQUID CRYSTAL COPOLYESTERS WITH X-SHAPED AND ROD-SHAPED MESOGENIC UNITS

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Chinese Journal of Polymer Science 1998年第1期16卷 48-55页

作者：李自法李磊张淑媛郑世军曹少魁赵丽婷周其凤 Department of Materials Engineering Zhengzhou University Zhengzhou 450052 China dept. of Polym. Sci. and Eng. the College of Chemistry Peking Univ. Beijing 1000871 China

A series of main chain liquid crystal aromatic copolyesters with X-shaped and rod-shaped mesogenic units were synthesized via solution condensation polymerizations of 4,4'-(alpha,omega-octanedioyloxy)-dibenzoyl dichlorides with 2,5-bis(p-octanoxy benzoyloxy)-hydroquinone and diphenol. All of the copolyesters showed thermotropic liquid crystalline behaviors through observations using DSC, polarized microscopy and X-ray diffraction. The melting point (T-m) and the isotropization temperature (T-i) change regularly with varying the content of diphenol unit in the copolymers.

关键词： liquid crystal polymer X-shaped and rod-shaped mesogenic units aromatic copolyester synthesis and characterization

Nano-indentation profiles of intrinsic hardness and modulus of films based on silsesquioxane modified with titanium tetrabutoxide

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Journal of Harbin Institute of Technology(New Series) 2004年第6期11卷 644-648页

作者：陈平孙科军刘今成崔津津胡立江 Chemstry Center Harbin University of Commerce Harbin 1500076China dept. of Applied chemistry Harbin Institute of Technology Harbin 150001China dept. of Optoelectronic Science and Technology Harbin Institute of Technology Harbin 150001 China

This study is to analyze the influence of the modifier, 5～25 wt % titanium tetrabutoxide (TBO), on the hardness and elastic modulus of the films based on SSO deriving from hydrolytic condensation of (3-glycidoxypropyl)trimethoxysilane (GPMS) and vinyltrimethoxysilane (VMS), by the continuous stiffness measurement (CSM) technique of an instrumented-indentation testing (IIT) device. Films were synthesized by adding the stoichiometric amount of ethylenediamine (EDA) and benzoyl proxide (BPO) to SSO solutions in ethanol, dip-coating over glass substrates, and curing using an appropriate thermal cycle. Intrinsic values of hardness and elastic modulus were determined with the average values in “plateau region” from “four-layer” explanation. And the brittle index of the modified coating systems was analyzed.

关键词：纳米结构材料硅半环氧乙烷硅化作用改性四丁氧钛硬度弹性模数 3-缩水甘油氧丙基三甲氧硅烷乙烯基三甲氧硅烷

Nano-scratch test for POSS films based on vinyltrimethoxysilane and modified with titanium tetrabutoxide

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Journal of Harbin Institute of Technology(New Series) 2005年第2期12卷 124-128页

作者：陈平胡立江刘金成崔津津 Chemstry Center Harbin University of Commerce Harbin 150076 China dept. of Applied chemistry Harbin Institute of Technology Harbin 150001 China dept. of Optoelectronic Science and Technology Harbin Institute of Technology Harbin 150001 China

Polyhedral oligomeric Silsesquioxanes (POSS) derived from vinyltrimethoxysilane (VMS) and modified with titanium tetrabutoxide (TTBO) (PVT) were prepared by sol-gel process catalyzed by hydrochloric acid (molar ratio: [HCl]/Si=0.05), and heating at 45 ℃ during 3 days. The PVT films (f-PVT) with different TTBO content, 5, 20 and 25wt% TTBO, were prepared by adding the stoichiometric amount of benzoyl peroxide (BPO) to PVT solutions in ethanol, dip-coating over glass substrates, and curing using an appropriate thermal cycle and time. The hardness and elastic modulus of f-PVT were tested by continuous stiffness measurement (CSM) of nanoindentation, and the tribological behaviors were comparatively investigated with a nanoscratch test. The influence of the different TTBO contents on the mechanical properties of f-PVT was discussed. The scratch and friction coefficient profiles of f-PVT were illustrated. As the results of the test, f-PVT with 20% TTBO showed the better scratch resistance and tribological behavior.

关键词： VMS 钛化合物溶胶过程摩擦测试 POSS薄膜