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Science China Mathematics 2005年第5期48卷 680-702页

作者： xu Yuesheng & ZOU Qingsong Department of Mathematics, Syracuse University, Syracuse, NY 13244, USA institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, {5. 100080, China Department of Scientific Computing and Computer Science, Zhongshan University, Guangzhou 5.0275. China 1. Department of Mathematics Syracuse University 13244 Syracuse NY USA 2. institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 3. Department of Scientific Computing and Computer Science Zhongshan University 510275 Guangzhou China

We construct a tree wavelet approximation by using a constructive greedy scheme (CGS). We define a function class which contains the functions whose piecewise polynomial approximations generated by the CGS have a prescribed global convergence rate and establish embedding properties of this class. We provide sufficient conditions on a tree index set and on bi-orthogonal wavelet bases which ensure optimal order of convergence for the wavelet approximations encoded on the tree index set using the bi-orthogonal wavelet bases. We then show that if we use the tree index set associated with the partition generated by the CGS to encode a wavelet approximation, it gives optimal order of convergence.

关键词： greedy algorithms tree wavelet approximations Besov spaces.

REVERSED POLARITY PATCHS AT THE CMBAND GEOMAGNETIC FIELD REVERSAL

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REVERSED POLARITY PATCHS AT THE CMBAND GEOMAGNETIC FIELD REV...

The Effect of chinese Tea on Occurrence of Esophageal Tumor Induced by N-Nitrosomethylbenzylamine in Rats

中国科学院地质与地球物理研究所2002学术年会

作者： xu Wen-Yao,Wei Zi-Gang institute of geology and geophysics,chinese {5. of {5.,beijing 100101

The International Geomagnetic Reference Field models(IGRF) for 1900-2000 are used to calculate the geomagnetic field distribution in the Earth’ interior from the ground surface to the core-mantle boundary(CMB) under the assumption of insulated *** reversed polarity patches,as one of the most important features of the CMB field,are *** patches with +Z polarity(downward) at the southern African and the southern American regions stand out against the background of -Z polarity (upward) in the southern hemisphere,and two patches of -Z polarity at the North Polar and the northern Pacific regions stand out against the +Z background in the northern *** the 1900-2000 period the southern African(SAF) patch has quickly drifted westward at a speed of 0.2 - 0.3°/α;meanwhile its area has expanded by 5.times,and the magnetic flux crossing the area has intensified by 30 *** the other hand,other three patches shows little if any changes during this 100 year *** upward, each of the reversed polarity patches at the CMB forms a chimney-shaped"reversed polarity column"in the mantle with the bottom at the *** height of the SAF column has grown rapidly from 200km in 1900 to 900km in *** the column grows steadily at the same rate in the ftiture,its top will reach to the ground surface in 600-700 *** then a reversed polarity patch will be observed at the Earth’s surface,which will be an indicator of the beginning of a magnetic field *** the basis of this study,one can describe the process of a geomagnetic polarity reversal:the polarity reversal may be observed firstly in one or several local regions;then the areas of these regions expand,and at same time,other new reversed polarity regions may *** several poles may exist during a polarity reversal.

关键词： geomagnetic field core-mantle boundary reversed polarity patch reversed polarity column polarity reversal of the geomagnetic field

来源： cnki会议评论

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Biomedical and Environmental sciences 1990年第1期3卷 35-42页

作者： HI AND xu YONG institute of Nutrition and Food Hygiene, chinese academy of Preventive Medicine, beijing, China institute of Nutrition and Food Hygiene Chinese Academy of Preventive Medicine Beijing.

Five groups of rats (40 rats per group) were given five different varieties of chinese tea (1 g/5. ml) and another two groups of rats (a positive control and a negative control) were given tap water as drinking water. Except for the negative control group, all the animals were intubated with A'-nitrosomethyibenzylamine (NMBzA, 5.mg/kg body wt/week). Half of the animals in each group were sacrificed after 6 weeks and the remaining animals at the end of 12 weeks. The incidences of esophageal mucosa lesions (16-5.%) at the end of6 weeks were significantly lower in the tea-treated rats than in the positive control group (100%). The incidences of esophageal tumor at the end of 12 weeks (42-67%) were also significantly lower in the tea-treated groups than in the positive control group (90%). The same phenomenon was found with respect to the size and number of tumors in each tumor-bearing animal. The relative anticarcinogenic effects of the five varieties of chinese tea were different. The Fujian oolong tea and jasmine tea exhibited the strongest effects. The results suggest that chinese tea can effectively inhibit the carcinogenesis Caused by an N-nitroso compound. 1990 Academic ***.

关键词： The Effect of chinese Tea on Occurrence of Esophageal Tumor Induced by N-Nitrosomethylbenzylamine in Rats

Studies on the Chemical Constituents of Lysimachia capillipes Hemsl

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chinese Chemical Letters 1998年第12期9卷 0-0页

作者： Chen XIE Li Zhen xu Bao Hua ZHAO and Shi Lin YANG(institute of Medicinal Plant Development, chinese academy of Medical sciences and PekingUnion Medical College, {5. 100094) chinese Acad Med Sci Inst Med Plant Dev Beijing 100094 Peoples R China Peking Union Med Coll Beijing 100094 Peoples R China

Eight compounds were isolated from the ethanolic extracts of Lysimachia capillipes Hemsl. They were identified as capilliplactone 1, capillipnin 2,beta-daucosterol 3, succinic acid 4, quercetin 5. 3',4',5.5.,7-pentahydroxyflavone 6, quercetin-3-O-beta-D-glucopyranoside 7 and kaempferol 8 on the basis of chemical and spectral methods. Among them, 1 and 2 were new, their structures were established as all-cis-5.deoxy-pentonic acid-gamma-lactone and 1,2,4,5.-tetrahydroxy-3-n-pentylbenzen-2,4-di-O-beta-D-glucopyranoside through their spectral data ((HNMR)-H-1, (CNMR)-C-13, DEFT, H-1-H-1 COSY, H-1-C-13 COSY, HMBC etc).

关键词： Lysimachia lysimachia capillipes, capillplactone capillipnin

Three-dimensional decomposition method of global atmospheric circulation

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Science China Earth sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, xu Ming5.& CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, institute of Atmospheric Physics, chinese academy of sciences, beijing 1.0029, China 2 Graduate University of chinese academy of sciences, {5. 100049, China 3 {5. Climate Center, {5. 100089, China 4 Department of Mathematics, Lanzhou University, Lanzhou 730000, China 5.Shanghai Typhoon institute, Shanghai 200030, China 6 Department of Atmospheric sciences, Lanzhou University, Lanzhou 730000, China 7 China Meteorological Administration Training Center, {5. 100089, China 1. State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. beijing Climate Center Beijing 100089 China 4. Department of Mathematics Lanzhou University Lanzhou 730000 China 5. Shanghai Typhoon institute Shanghai 200030 China 6. Department of Atmospheric sciences Lanzhou University Lanzhou 730000 China 7. China Meteorological Administration Training Center Beijing 100089 China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

The Tethyan-Himalayan Orogenic Complex

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Continental Dynamics 1996年第1期 20-29页

作者： Cui Junwen and xu Zhiqin(institute of geology chinese academy of Geological {5., {5. 100037,China)

ＴｈｅＴｅｔｈｙａｎ－ＨｉｍａｌａｙａｎＯｒｏｇｅｎｉｃＣｏｍｐｌｅｘ￥ＣｕｉＪｕｎｗｅｎａｎｄＸｕＺｈｉｑｉｎ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＧｅｏｌｏｇｉｃａｌＳｃｉｅｎｃｅ... 详细信息

ＴｈｅＴｅｔｈｙａｎ－ＨｉｍａｌａｙａｎＯｒｏｇｅｎｉｃＣｏｍｐｌｅｘ￥ＣｕｉＪｕｎｗｅｎａｎｄＸｕＺｈｉｑｉｎ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＧｅｏｌｏｇｉｃａｌＳｃｉｅｎｃｅｓ，Ｂｅｉｊｉｎｇ１０００３７，Ｃ...

关键词： Himalayan

STUDY ON ERAS OF DATONG VOLCANIC ACTIVITIES BY THERMOLUMINESCENCE DATING

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Science in China,Ser.B 1984年第10期27卷 1069-1080页

作者：李虎侯孙建中 institute of Archaeology chinese academy of Social sciences beijing institute of geology State Bureau of Seismology

This paper reports that the ages determined on the baked strata of 8 typical seciionsin the Datong volcanic cluster are within (0.98±0.02)×10~5.r. and (2.9±0.2)×10~5.r B. *** using quartz thermoluminescence dating technique. The age values and stratigraphical position of the volcanic lava flow reveal that 4 typi-cal sections may be taken for the study of thc eras of Datong volcanic activities, i. e. the Yu-jiazhai section, 300,000 yr B. P.; the Yuangou section, 200,000 yr B. P.; the South Canyonsection of Heishan, 15.,000 yr B. P.; the Huangjiawa section, 100,000 yr B. P.

关键词： STUDY ON ERAS OF DATONG VOLCANIC ACTIVITIES BY THERMOLUMINESCENCE DATING

InGaAs/GaAs/InGaP Strained Quantum Well Lasers Grown by Metalorganic Chemical Vapor Deposition

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Journal of Semiconductors 1998年第7期 69-72页

作者： Yang Guowen xu Zuntu Ma Xiaoyu xu Junying Zhang Jingming Chen Lianghui (institute of Semiconductors, The chinese academy of sciences, beijing 100083)

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｒａｉｎｅｄＩｎＧａＡｓ／ＧａＡｓｑｕａｎｔｕｍｗｅｌ（ＱＷ）ｌａｓｅｒｓｗｉｔｈｅｍｉｓｉｏｎｗａｖｅｌｅｎｇｔｈｏｆ９８０ｎｍａｒｅｃｕｒｅｎｔｌｙｒｅｃｅｉｖｉｎｇｃｏｎｓｉｄｅｒａｂｌｅａｔｅｎｔｉｏｎｂｅｃａｕ...

关键词： InGaAs/GaAs/InGaP Strained Quantum Well Metalorganic Chemical Deposition

Primary scientific results of Chang'E-1 lunar mission

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Science China Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5. WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, xu Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012, China 2 institute of Geochemistry, chinese academy of sciences, Guiyang 5.0002, China 3 Xi’an institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, China 4 Shanghai institute of Technical Physics, chinese academy of sciences, Shanghai 200083, China 5.Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, China 6 institute of High Energy Physics, chinese academy of sciences, beijing 100049, China 7 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190, China 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China3. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710119 China4. Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China5. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China6. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China7. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 5..36°E, 1.5.°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495.days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results