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Dynamical Evolution of Gamma-Ray Burst Remnants with Evolving Radiative Efficiency

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 525-532页

作者： Jin-Bo Feng, Yong-Feng Huang, Zi-Gao Dai and Tan Lu1 Department of Astronomy, Nanjing University, Nanjing 2.0093.0}LCRHEA, Institute for High-Energy Physics, chinese {3. of {2., beijing 10003. LCRHEA Institute for High-Energy Physics Chinese Academy of Sciences Beijing 100039

In previous works, a generic dynamical model has been suggested by Huang. et al., which is shown to be correct for both adiabatic and radiative blast-waves, in both ultra-relativistic and non-relativistic phases. In deriving their equations, Huang et al. have assumed that the radiative efficiency of the fireball is constant. They then applied their model directly to realistic cases where the radiative efficiency evolves with time. In this paper, we abandon the above assumption and re-derive a more accurate dynamical equation for gamma-ray burst remnants. Numerical results show that the model presented by Huang et al. is accurate enough in general cases.

关键词： gamma rays : bursts hydrodynamics radiation mechanisms : nonthermal

An adaptive algorithm for pass adaptation in plate rolling

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Journal of University of Science and Technology beijing 2002年第5期9卷 396-399页

作者： Zhichun Mu, WeimingLi, and Ke LiuInformation Engineering school, University of Science and Technology beijing, beijing 100083.{3. Information Engineering school University of Science and Technology Beijing Beijing 100083 China

A new algorithm for pass adaptation in plate rolling is developedto improve thickness accuracy of plate products. The feature of thealgorithm is that it uses the measured data rather than the schedulecalculated data in adaptation, which leads to notable improvem- entin prediction accuracy of the rolling parameters and thicknessaccuracy of products can be improved according. Results show thatthis adaptive algorithm is effective in practice.

关键词： adaptive algorithm plate rolling measured data

The 3.channel High-Speed Photometer at beijing Astronomical Observatory

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天文研究与技术 1999年第S1期 68-71页

作者： Jiang Xiaojun 1,2.1 beijing Astronomical Observatory, The chinese {2. of sciences, beijing 100012. china Email: xjjiang @ class1. bao. ac. cn 2.National Astronomical Observatories, The chinese {2. of sciences

A 2.channel photometer was upgraded to a Whole Earth Telescope (WET) high speed 3.channel photometer at beijing Astronomical Observatory (BAO). The structure and functions of the photometer are discussed. The data obt...

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Controlling the Molecular Weight and Molecular Weight Distribution using Compressed CO_2.Antisolvent

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chinese Chemical Letters 2000年第10期11卷 933-934页

作者： Jun LIU, Zhi Min LIU, Bu Xing HAN, Jian WANG, Qing HUO, Fang Fang LIU (Center For Molecular sciences, Institute of Chemistry, chinese {2. of sciences, beijing 100080 (Chemical Engineering College of beijing United University, beijing 10002.) (Department of Chemical Engineering, University of Science and Technology of Hebei, Shijiazhuang 050018) chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China beijing United Univ Chem Engn Coll Beijing 100023 Peoples R China Univ Sci & Technol Hebei Dept Chem Engn Shijiazhuang 050018 Peoples R China

Effect of CO2.dissolved in tetrahydrofuran (THF) on the polymerization of styrene in THF was studied at 3.3.2.K and different pressures. It was found that the molecular weight (MW) and MW distribution of the polystyre... 详细信息

关键词： CO_2 antisolvent styrene polymerization

A NEW METHOD FOR THE AROMATIZATION OF 18-METHYL-ESTRA-4(5), 9(10)-DIEN-3.17-DIONE

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chinese Chemical Letters 1992年第6期3卷 419-420页

作者： Guang Disn HAN Hong Yau WEN Institute of Materia Medica, chinese academy of Medical {2., {3., 100050

An aromatization reaction was found when 18--methyl--estra--4(5), 9(10)--dien--3. 17--dione(6) was treated with triethyl orthoforrnate in dioxane in the presence of catalytic amount of p--toluenesulfonic acid (TsOH), and 18--methyl--9(11) --dehydroestrone--3.-ethyl ether (8) was obtained in 70% yield. The mechanism was found to be a process of etherification--oxidation reaction.

关键词： Th ppm A NEW METHOD FOR THE AROMATIZATION OF 18-METHYL-ESTRA-4 DIEN-3.17-DIONE

A MILD AND REGIOSPECIFIC OXIRANE RING OPENING TO PRECURSORS FOR PROSTANOID CONGENERS

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chinese Chemical Letters 1993年第9期4卷 757-758页

作者： Ai Lian ZHENG Yuan Liu WU Institute of Materia Medica,chinese academy of Medical {2.,{3. 100050

A stereoselective and regiospecific synthesis of procursors(2.,(4),(6)and(7)of prostacyclin analogues from 2.3.epoxylbicyclo[3.2.0]hept-6-one(1)are described.

关键词： MILD A MILD AND REGIOSPECIFIC OXIRANE RING OPENING TO PRECURSORS FOR PROSTANOID CONGENERS

Geochemical evidence for submarine hydrothermal origin of the Middle-Upper Permian chert in Laibin of Guangxi,china

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Geochemical evidence for submarine hydrothermal origin of th...

Magneto-optical Enhancement Effect in MnBixAl0.15 Films

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： QIU Zhen~(1,2. & WANG QingChen~(1*) 1 State Key Laboratory of Litho spheric Evolution,Institute of Geology and Geophysics,chinese academy of {2.,beijing 10002.,china 2.Graduate University of chinese academy of {2.,beijing 100049,china

Lithologically,two kinds of chert can be recognized in the Middle-Upper Permian from the Tieqiao section in Laibin area, Guangxi,i.e.,calcic chert occurring mainly in the Maokou Formation and pure chert mainly in the Wujiaping *** data show that both kinds of chert contain very low A1O(0-0.2.%) and TiO(0.001%-0.02.%) and low∑REE (0.55-19.94 ppm,averaging 9.97 ppm),as well as high ratio of FeO/TiO(17-443.averaging 111) and low ratio of AlO/(AlO+FeO)(0-0.2.,averaging 0.09).Given that the average value Ce anomalies in chert deposited in the ridge-proximal environment is about 0.2.,and that in the pelagic environment is about 0.60,the low Ce anomalies in the Tieqiao chert(0.2.-0.46,averaging 0.3.) imply that they were deposited in an ocean basin with influence of submarine hydrothermal fluid and no input of terrigenous *** vertical variation of the silica abundance in strata(SAIS) in the Middle-Upper Permian strata,together with the Eu anomalies and the ratios of∑REE/Fe,indicates a relationship between the hydrothermal activity and the Emeishan basalt eruption,and that submarine hydrothermal activity was stronger in the Upper Permian(the Wujiapingian Stage) than in the Middle Permian(the Maokou Stage).

关键词： chert geochemistry submarine hydrothermal fluid Emeishan basalt

来源： cnki会议评论

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电子显微学报 1997年第4期 57-60页

作者： C.H.Shang\ Y.J.Wang (Institute of Physics, chinese academy of {2., {3. 100080)

ＭａｇｎｅｔｏｏｐｔｉｃａｌＥｎｈａｎｃｅｍｅｎｔＥｆｅｃｔｉｎＭｎＢｉｘＡｌ０１５ＦｉｌｍｓＣ．Ｈ．ＳｈａｎｇＹ．Ｊ．Ｗａｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＰｈｙｓｉｃｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃ... 详细信息

ＭａｇｎｅｔｏｏｐｔｉｃａｌＥｎｈａｎｃｅｍｅｎｔＥｆｅｃｔｉｎＭｎＢｉｘＡｌ０１５ＦｉｌｍｓＣ．Ｈ．ＳｈａｎｇＹ．Ｊ．Ｗａｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＰｈｙｓｉｃｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ，Ｂｅｉｊｉｎｇ１０００８０）...

关键词： MnBi_xAl Magneto-optical Films Effect Enhancement

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 academy of Medical {2. & Peking Union Medical College, {3. 100050, china bNational Institute for the Control of Pharmaceutical and Biological Products, {3. 100050, china cInstitute of Medicinal Biotechnology, chinese academy of Medical {2. & Peking Union Medical College, {3. 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