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脂肪酶催化缩聚法合成可完全降解的聚羟基丙酸酯(英文)

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催化学报 2012年第3期33卷 432-438页

作者：宋昊赵永杰张颖鑫孔维宝夏春谷中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室甘肃兰州730000 中国科学院研究生院北京100049

以3-羟基丙酸甲酯为聚合单体,建立了以固定化脂肪酶Novozym 435为催化剂的酶催化缩聚反应体系,合成可完全降解的高分子聚酯聚羟基丙酸酯,考察了反应条件和介质对反应性能的影响,结果表明,纯度大于95%的单体即可在温和条件下合成聚羟基... 详细信息

以3-羟基丙酸甲酯为聚合单体,建立了以固定化脂肪酶Novozym 435为催化剂的酶催化缩聚反应体系,合成可完全降解的高分子聚酯聚羟基丙酸酯,考察了反应条件和介质对反应性能的影响,结果表明,纯度大于95%的单体即可在温和条件下合成聚羟基羧酸酯;降低反应压力可有效提升产物产率和分子量.通过选择合适的有机溶剂介质和表面活性剂,可使产物分子量提升至13000(Mw)以上.脂肪酶催化剂重复利用能力优异,经6批次反应后,其相对活性保持在95%以上.

关键词：聚羟基羧酸酯聚合酶催化脂肪酶 3-羟基丙酸甲酯

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JOINTING STRUCTURE CHARACTERIZATION FOR THE PRESELECTED AREA OF CHINA'S DEEP geological DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTE

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JOINTING STRUCTURE CHARACTERIZATION FOR THE PRESELECTED AREA...

第三届废物地下处置学术研讨会

作者： Guibin Wang~1,Chunhe Yang~1,Wang Ju~2.Liming Yin~1 (1.State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of Rock and Soil Mechanics,the chinese{2. of Science:Wuhan 430071,China 2.beijing Research institute of Uranium geology:beijing 10002.,China)

Jointing structure is considered in most of the rock mass classification systems and it takes a great weight in those rock mass classification ***,the rock mass classification systems take different parameters for characterizing jointing structure and most rock engineering is carried out using various descriptions.A general jointing structure characterization method is of great significance for site selection,repository design and performance assessment for high-level radioactive waste *** paper concentrates on a common approach to jointing structure characterization and the results for Beishan area,Gansu province,the preselected area of China’s deep geological disposal of high-level radioactive waste.A synthesis index,JSR(Jointing Structure Rating),is developed to characterize the jointing structure of rock *** main principle in the development of JSR is concentrated on the cleavage of rock mass by joints regardless of this cleavage may reduce the strength or increase the permeability of rock *** is the combination of joint density,joint size and joint set *** may serve as a general index which can be used to evaluate both the block size of rock mass and the connectivity of joints *** main joints characterization such as orientation,joint set number,mean trace length and midpoint density is evaluated after detailed field joint survey in Beishan *** on JSR and joints statistical description,jointing structure classification for the sections of Beishan area is *** results provide a global vision of the jointing structure in Beishan area and provide a basis for site selection and preliminary near-field performance assessment.

关键词： High-level radioactive Waste rock mass joints Jointing structure rating Beishan area

EFFECT OF GOSSYPOL ON THE POTENTIAL DIFFERENCE OF RAT SEMINIFEROUS TUBULES

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Science in China,Ser.B 1985年第4期28卷 402-409页

作者：吴嬿婉佟大山袁冬王乃英宗书东谢益宽 National Research institute for Family Planning beijing Department of Physiology institute of Basic Medical sciences chinese academy of Medical{2.

The p.d. of the rat seminiferous tubules was 4.75±1.39 mV (lumen negative) at 35℃ and varied linearly with temperatures from 2. to 40℃.A depolarization of the seminiferous tubules was found in the rats administered with gossypol at the dosage of 30 mg/kg body weight for 3 weeks, the p.d. lowered to 3.63±0.79 mV at 35℃ and was independent of the changes of seminiferous tubules temperature. In the 5-week-gossypol-treatment group, the tracer penetrated not only the myoid cell layer, but also went beyond the tight junction complexes between Sertoli cells. The lanthanum appeared in the cleft surrounding spermatogonia. In the 8-week-gossypol-treatment group, the lanthanum was found in the adluminal *** indicates that gossypol can cause a dysfunction of the Sertoli cells and blood-testis barrier and disturb a good physiological environment for the developing spermatecytes.

关键词： EFFECT OF GOSSYPOL ON THE POTENTIAL DIFFERENCE OF RAT SEMINIFEROUS TUBULES

Systematic study of the transfer of amino acids across the water/1,2.dichloroethane interface facilitated by dibenzo-18-crown-6

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Science China Chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical Chemistry, Changchun institute of Applied Chemistry, chinese{2. of sciences, Changchun 13002., China College of Chemistry and Molecular Engineering, Peking University, beijing 100871, China Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and Molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 2. amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2.dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2.dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

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Bio-Inspired,Smart,Multiscale Interfacial Materials

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Bio-Inspired,Smart,Multiscale Interfacial Materials

第六届全国化学生物学学术会议

作者： Lei Jiang institute of Chemistry.,chinese{2. of sciences,beijing 100190,China

Bio-inspired smart material should be a"live"material with various functions like organism in nature, they must have three essential elements as sense,drive and *** recent studies are focused on the design and fabrica...

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A New Formal Test Suite Specification Language For IPv6 Conformance Testing

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A New Formal Test Suite Specification Language For IPv6 Conf...

2.03 International Conference on Communication Technology

作者： ZhangYujun LiZhongcheng institute of Computing Technology,chinese{2. of sciences,beijing, China 100080

IPv6 is the next generation Internet protocol. More and more productions supporting IPv6 have been developed, which makes IPv6 conformance testing necessary. The test suite specification language is v

关键词： -IPv6 conformance testing test suite specification language TSSL

SEDIMENTARY SUCCESSIONS OF DALONG FORMATION, MATAN, GUANGXI PROVINCE AND THEIR ENVIRONMENTAL IMPLICATIONS

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Scientia Geologica Sinica 2000年第2期 237-245页

作者： LAN Chaoli LI Jiliang ZHANG Xiaohui YU Liangjun (institute of geology and Geophysics.{2. academy of sciences, beijing 10002.) XIA Wenchen (China University of Geosciences, Wuhan 430074)

Dalong Formation of Matan is mainly composed of pyroclastic rocks and siliceous rocks. Microscopic analysis shows : (1) pyroclastic rocks can be divided into three subtypes, namely tuffs, sedimentary-tuffs and tuffaceous sedimentary rocks, and further into seven types of microfacies, (2. siliceous rocks can be divided into two subtypes, namely biogenic siliceous rocks, biogenic and volcanogenic siliceous rocks, and further into five types of microfacies. These microfacies comprise twelve types of main lithofacies,which can vertically be grouped into six types of sedimentary succession. These successions indicate there are two types of turbidity current. One is low-density turbidity current which is evolved from high-density turbidity current generated by pyroclastic debris current induced by subaqueous volcanic eruption, the other is that is induced by slumps and brings early sediments of tuffaceous grains and siliceous biogenic grains. Our research into sedimentary successions and geomorphology of Matan area at this stage demonstrates that there do not exist submarine fans. On the contrary, it accepts low-density tuffaceous turbidity current readily, resulting in extensively and relatively thin-bedded deposits

关键词： Zhang MATAN SEDIMENTARY SUCCESSIONS OF DALONG FORMATION GUANGXI PROVINCE AND THEIR ENVIRONMENTAL IMPLICATIONS

Square Wave Control of 3-Level NPC Inverter for Large Capacity High-Speed Drive Systems

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Square Wave Control of 3-Level NPC Inverter for Large Capaci...

2.05国际电机与系统学术会议

作者： Haishan Li Yaohua Li institute of Electrical Engineering. chinese{2. of sciences beijing 100080 China Graduate School of chinese{2. of sciences beijing 100080 China

＜正＞This paper presents an improved method to achieve the high control performance of 3-level inverter for large capacity high-speed drive systems. Usually, due to the limit switching frequency of high voltage high power devices, the output frequency of the inverter is low in most cases. To achieve higher output frequency, the square wave modulation （SWM） is adopted. However, the use of the normal SWM decreases the control performance of the inverter and deteriorates the dynamic behavior of the drive systems because of less control freedom in per fundamental period. The proposed method with the improvement of the normal SWM has twelve freedoms and the optimum operation region of this method is given. Experimental results show that the proposed method can be applied in three level NPC inverters especially for large capacity highspeed drive systems.

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High performance liquid chromatographic separation of thirteen drugs collected in chinese Pharmacopoeia 2.10(Ch.P2.10) on cellulose ramification chiral stationary phase

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Journal of Pharmaceutical Analysis 2012年第1期2卷 48-55页

作者： Ying Zhoua,b, Chao Maa, Yan Wanga, Qi-Ming Zhangb, Yi-Ying Zhanga, Jie Fua, Hong Gaoc, Li-Xun Zhaoc aState Key Laboratory of Bioactive Substances and Functions of Natural Medicines, institute of Materia Medica, chinese{2. of Medical sciences & Peking Union Medical College, beijing 100050, China bNational institute for the Control of Pharmaceutical and Biological Products, beijing 100050, China cinstitute of Medicinal Biotechnology, chinese{2. of Medical sciences & Peking Union Medical College, beijing 100050, China State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China. National institute for the Control of Pharmaceutical and Biological Products Beijing 100050 China. institute of Medicinal Biotechnology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China.

The enantiomers separation of thirteen drugs collected in Ch.P2.10 was performed on chiral stationary phase of cellulose ramification (chiralpak OD and chiralpak OJ) by high performance liquid chromatographic (HPLC) methods, which included ibuprofen (C1), ketoprofen (C2., nitrendipine (C3), nimodipine (C4), felodipine (C5), omeprazole (C6), praziquantel (C7), propranolol hydrochloride (C8), atenolol (C9), sulpiride (C10), clenbuterol hydrochloride (C11), verapamil hydrochloride (C12., and chlorphenamine maleate (C13). The mobile phase consisted of isopropanol and n-hexane. The detection wavelength was set at 2.4 nm and the fiow rate was 0.7 mL/min. The enantiomers separation of these thirteen racemates on chiralpak OD column and chiralpak OJ column was studied, while the effects of proportion of organic additives, alcohol displacer and temperature on the separation were studied. And the mechanism of some of racemates was discussed. The results indicated that thirteen chiral drugs could be separated onchiral stationary phase of cellulose ramification in normal phase chromatographic system. The chromatographic retention and resolution of enantiomers could be adjusted by factors including column temperature and the concentration of alcohol displacer and organic alkaline modifier in mobile phase. It was shown that the resolution was improved with reducing concentration of alcohol displacer. When concentration of organic alkaline modifier was 0.2. (v/v), the resolution and the peak shape were fairly good. Most racemates mentioned above had better resolution at column temperature of 2. 1C. When racemates were separated, the temperature should be kept so as to obtain stable separation results.

关键词： HPLC Chiral stationary phase Optical enantiomers Cellulose ramification

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