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An efficient chiral synthesis of (R)-N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3.1 Technical Institute of Physics and Chemistry,chinese academy of {2.,beijing 100080,china 2.College of Chemistry and Chemical Engineering,Graduate university of chinese academy of {2.,beijing 100049,china 3.School of Chemical Engineering and Environment,beijing Institute of Technology,beijing 100081,china 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4-(2.hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Direct Optimization of Low-thrust Many-revolution Earth-orbit Transfers

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chinese Journal of Aeronautics 2009年第4期22卷 426-433页

作者： Gao Yang academy of Opto-Electronics,chinese academy of {3.,beijing 100190,china [a]academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China

Low-thrust Earth-orbit transfers with 10^- 5-order thrust-to-weight ratios involve a large number of orbital revolutions which poses a real challenge to trajectory optimization. This article develops a direct method to optimize minimum-time low-thrust many-revolution Earth-orbit transfers. A parameterized control law in each orbit, in the form of the true optimal control, is proposed, and the time history of the parameters governing the control law is interpolated through a finite number of nodal values. The orbital averaging method is used to significantly reduce the computational workload and the trajectory optimization is conducted based on the orbital averaging dynamics expressed by nonsingular equinoctial elements. Furthermore, Earth＇s shadowing and perturbation effects are taken into account. The optimal transfer problem is thus converted to the parameter optimization problem that can be solved by nonlinear programming. Taking advantage of the mapping between the parameterized control law and the Lyapunov control law, a technique is proposed to acquire good initial guesses for optimization variables, which results in enlarged convergence domain of the direct optimization method. Numerical examples of optimal Earth-orbit transfers are presented.

关键词： low thrust orbital transfer optimization direct method orbital averaging Lyapunov method

High Throughput SNP Genotyping with Two Mini-sequencing Assays

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 379-384页

作者： Chunqing LUO1,2., Libin DENG1#, and Changqing ZENG1,2. The Institute of Genetic and Developmental Biology, the chinese {3. of {2., beijing 100101, china 2.3. Genomics Institute, the chinese {3. of {2., beijing 1013.0, china The Institute of Genetic and Developmental Biology the Chinese Academy of SciencesBeijing 100101 China beijing Genomics Institute the Chinese Academy of SciencesBeijing 101300 China

Two mini-sequencing methods, FP-TDI (template-directed dye-terminator incorporation with fluorescence-polarization) and MassArray (matrix assisted laser desorption ionization time of flight detection mass spectrometry), were optimized. A numeric standard was introduced to evaluate the SNP scoring quality of FP-TDI assay, thus made the optimization work easier. At the same time, using multi-PCR technology, 8-plex genotyping of MassArray assay was successfully carried out, some softwares were developed and the data process of MassArray was highly automated. Then these two methods were applied to high throughput SNP genotyping, the accuracy, efficiency and robustness were compared. The result shows FP-TDI is more sensitive to the concentration of SNPprimer and PCR product, as well as extension cycles, the SNPprimer length of FP-TDI should be 2.–3. bp long, whereas MassArray assay prefers to be as short as only 16 *** 6440 SNP sites of human chromosome 3.were genotyped in a sample of 90 individuals, 4792.sites by FP-TDI assay and 1648 sites by MassArray assay, the success rates of FP-TDI and MassArray were 67.7% and 93.6% respectively. The throughput of MassArray was higher than FP-TDI, and the cost of MassArray was lower, MassArray was more suitable for high throughput SNP genotyping.

关键词： SNP genotyping FP-TDI MassArray high throughput

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(3.)Ar age dating of Dur'ngoi ophiolite

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chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI Xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, Northwest university, Xi’an 710069, china 2. Department of Geology, Northwest university, Xi’an, 710069, china 3. Institute of Geology, chinese academy of Geological sciences, beijing, 10003., china Laboratory of Continental Dynamics Northwest University Xi’an China Department of Geology Northwest University Xi’an China Institute of Geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/3.Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (3.5.3.7.9 Ma) with an isochorn age (3.6.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -3.Ar age Paleo-tethys.

Plus cupping degrees do not form an ideal

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Science in china(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1,2.& ZHAO Yicheng1 1. Institute of Software,chinese academy of {2.,beijing 100080,china 2. School of Information {2.,beijing Normal university,beijing 100871,china 1. Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. School of Information sciences Beijing Normal University 100871 Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0

关键词： computably enumerable set Turing degree definability.

An H_2. flare in GGD2.

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chinese Science Bulletin 2001年第1期46卷 35-39页

作者： XU Ye, ZHENG Xingwu JIANG Dongrong, ZHANG Fujun& YU Zhiyao1. Shanghai Astronomical Observatory, chinese academy of {2., Shanghai 2.003., china 2. chinese National Observatories, chinese academy of {2., beijing 100080, china 3. Department of Astronomy, Nanjing university, Nanjing 2.0093. china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China chinese National Observatories Chinese Academy of Sciences Beijing China Department of Astronomy Nanjing University 210093 China

We report the observing results of a short time scale monitoring of the 2. GHz water maser emission in GGD2.. A rapid water maser outburst with the time scales of 4 d has been detected, and the variations are accompanied by some changes in the line width. The time variations were probably caused by a collision pump which led to changes in the pump input.

关键词： interstellar masers (ISM) individual GGD2. masers.

Discovery of low grade metamorphic volcanic rock sheets within UHP in Dabie Mts. and its implications

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chinese Science Bulletin 1997年第14期42卷 1199-1203页

作者： DONG Shuwen, WANG Xiaofeng and HUANG Dezhi1. chinese academy of Geological {2. (CAGS),{3., china 2. Institute of Geomechanics of CAGS, beijing 100081 china 3. Anhui Institute of Geological {2., Hefei 2.0001 chinese academy of Geological {2. (CAGS) Beijing 100037 China

THE ultrahigh-pressure metamorphic zone (UHP), outcropping in the central and southernDabie Mts. with an area of about 1000 km^2. may be the largest one in the world. The forma-tion and exhumation mechanism of the UHP rocks become a hot point in the study of continen-tal orogen. The first finding of the Shiqiao structural window, which is composed of low

关键词： ultrahigh-pressure metamorphic zone (UHP) low grade metamorphic rock sheets Dabie Mts.

Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2.& ZHAO ChangYin1 1 Purple Mountain Observatory, chinese academy of {2., Nanjing 2.0008, china 2.Graduate university of chinese academy of {2., beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate university of chinese {2. of {3. Beijing 100049 China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72. DTM94, NRLMSISE00 and JB2.06, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.72.0) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2.06 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2.06’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 2., 2.03. JB2.06 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest china:Evidence from sandstone detrital and geochemical records

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Science china Earth sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1, GUO Hong2. WANG Daoxuan3.& LIN Wei1 1. Institute of Geology and Geophysics, chinese academy of {2., beijing 10002., china 2. Tarim Oilfield Branch, CNPC, Korla 841000, china 3. Hefei university of Industry, Tunxilu 193. Hefei 2.0009, china 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. Hefei university of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest china, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1) From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2. For major element geo- chemical parameters of whole sandstones, CaO and Fe2.O * 3.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. (3. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2.3.(CaO+Na2.) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.