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Studies on the New Constituents of Sal via Miltiorrhiza Bunge

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Chemical Research in Chinese Universities 1992年第3期8卷 262-266页

作者： CEN Ying-zhou (department of Chemistry, university of {2., Guangzhou, 510632.WU Qiu-ming (Center of Analysis, university of {2., Guangzhou, 510632.

Two novel constituents were isolated from the roots of Chinese medicinal herbs, Salvia miltiorrhiza. Their structures were determined by spectroscopic technique. The compounds were named 13,14.dihydroxy-15-methyl-benzo[2.3-a]-7,7-dimethyl-12.oxa-tricyclo[4.4.2..4.0]dodecane(1) and 16-methyl-tropono[2.3-c]-7,7-dimethyl-12.oxa-tricyclo[4.4.2..4.0]dodecane(2..

关键词： Salvria miltiorrhiza 13,14.dihydroxy-15-methyl-benzo [2 3-a]-7,7-dimethyl-12.oxa-tricyclo [4 4 2.,4 0] dodecane 16-methyl-tropono [2 3-c]-7 7-dimethyl-12.oxa-tricyclo[4.4.2.,4.0] dodecane

Theoretical Perspectives on Natural and Artificial Micro-swimmers

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Acta Mechanica Solida Sinica 2021年第6期34卷 783-809页

作者： jinan Liu Yiqiang Fu Xiongjun Liu Haihui Ruan Research Center for Fluid-Structure Interactions Department of Mechanical EngineeringThe Hong Konssg Polytechnic UniversityHung HomKowloonHong KongChina State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing100083China

The observations of microorganisms revealed how they *** inspired by them,studies on artificial micro-robots with various actuation mechanisms have been *** elucidate the essential concepts in understanding the dynamic behaviors of natural and artificial micro-swimmers—so as to control the latter in future applications,in this paper,we summarize the historical achievements and describe our theoretical *** first introduce the studies on microorganisms and their propulsion *** reviewing the basic principles and the development of the understanding of them,we take the flagellated micro-swimmers as an example to elaborate on the theories of their *** review the progress in actuation strategies of artificial flagellated micro-swimmers and then propose two possible strategies to realize the turning of a flagellated micro-swimmer—the key step toward steerability through remote ***,we describe the inadequacies of the investigations on this topic and our perspectives on future developments.

关键词： Natural micro-swimmer Artificial micro-swimmer External field actuation Manipulation strategies Propulsion

Optimal Maximum Norm Estimates and Superconvergence for GDM on Two-point Boundary Value Problems

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Communications in Mathematical Research 1999年第1期 89-96页

作者： Li Qian and Jiang Ziwen (department of Mathematics, Shandong Normal university, {2., 2.0014.

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＲｅｃｅｎｔｌｙ，Ｌｉａｎｄｏｔｈｅｒａｕｔｈｏｒｓｄｉｄｅｘｔｅｎｓｉｖｅａｎｄｄｅｅｐｒｅｓｅａｒｃｈｏｎｔｈｅｔｈｅｏｒｙａｎｄａｐ－ｐｌｉｃａｔｉｏｎｏｆｇｅｎｅｒａｌｉｚｅｄｄ... 详细信息

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＲｅｃｅｎｔｌｙ，Ｌｉａｎｄｏｔｈｅｒａｕｔｈｏｒｓｄｉｄｅｘｔｅｎｓｉｖｅａｎｄｄｅｅｐｒｅｓｅａｒｃｈｏｎｔｈｅｔｈｅｏｒｙａｎｄａｐ－ｐｌｉｃａｔｉｏｎｏｆｇｅｎｅｒａｌｉｚｅｄｄｉｆｅｒｅｎｃｅｍｅｔｈｏｄｓ（ｓ...

关键词： Two point Boundary Value Problem GDM Maximum Norm Superconvergence Green’s Function

Sorption of Eu^(3+) onto nano-size silica-water interfaces

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Science China Earth Sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1,2. YIN Xiulan3 , ZHAO Linghu1 & LI Dien4.1. department of Earth Sciences, China university of Geosciences, Wuhan 4.0074. China 2. Northeastern Illinois university, Chicago, IL 6062., USA 3. China Institute of Geo-Environmental Monitoring, Beijing 100081, China 4. Division of Chemistry, Los Alamos National Laboratory, Los Alamos, NM 8754., USA 1. department of Earth Sciences China University of Geosciences 430074 Wuhan China 2. Northeastern Illinois university 60625 Chicago IL USA 3. China Institute of Geo-Environmental Monitoring 100081 Beijing China 4. Division of Chemistry Los Alamos National Laboratory 87544 Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1―8.5 and the initial Eu concentrations (CEu) of 2.× 10?5, 2.× 10?4.and 2.× 10?3 M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2.× 10?5, 2.× 10?4.and 2.× 10?3 M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75, ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.58 × 10?8, 1.58 × 10?7 and 1.58 × 10?6 mol/m2. The sorbed Eu species at pH 2. to ~6 at pH = 6. At pH = 6 – 8, Eu(OH)2., Eu(CO3)+ and Eu(CO3)2. form in the solutions, and Eu(CO3)+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3+ species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals

Anisotropic effect on the vibronic reduction factors

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Chinese Science Bulletin 2006年第21期51卷 2553-2558页

作者： QIU Qing-chun1,2.& QIAO Fen1,2.1. department of Physics and IT, Medical College, Shantou university,Shantou 51504., China 2. department of Physics, Shantou university, Shantou 515063, China department of Physics and IT Medical College Shantou University Shantou 515041 China department of Physics Shantou University Shantou 515063 China

The reduction factors p and q defined by Ham in the Ee JT system and their relation 2.-p=1 have been well accepted and the concept of reduction factors is widely used in the studies of vibronic coupling. However, when the system is under the anisotropic conditions, the reduction factors and their relation will change accordingly. The first-order reduction factors p and q of Ee system were further studied using the method of unitary transformation here. The relation between p and q proposed by Ham was investigated under both conditions of the linear coupling and the anisotropic effects. The result demonstrated that the relation of 2.-p=1 was only correct for the linear vibronic coupling, but not correct when the anisotropic effect was considered. This result suggested that the anisotropic effect influence considerably the reduction factors, and hence the physical properties of materials. Our method could be also applied to other JT systems, especially the highly symmetric JT systems involving C60 molecules.

关键词：电子振动耦合声子交迭 Jahn-Teller效应各向异性

NANOSTRUCTURES OF FUNCTIONAL BLOCK COPOLYMERS

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Chinese Journal of Polymer Science 2000年第3期18卷 255-262页

作者： Guojun Liu department of Chemistry, university of Calgary, 2.00 university Dr., NW, Calgary, Alberta, Canada T2. IN4 Univ Calgary Dept Chem Calgary AB T2N 1N4 Canada

Nanostructure fabrication from block copolymers in my group normally involves polymer design, synthesis, self-assembly, selective domain crosslinking, and sometimes selective domain removal. Preparation of thin films withnanochannels was used to illustrate the strategy we took. In this particular case, a linear triblock copolymer polyisoprenc-block-poly(2.cinnamoylethyl methacrylate)-block-poly(t-butyl acrylate), PI-b-PCEMA-b-PtBA, was used. Films, 2. to50 μm thick, were prepared from casting on glass slides a toluene solution of PI-b-PCEMA-b-PtBA and PtBA homopolymer,hPtBA, where hPtBA is shorter than the PtBA block. At the hPtBA mass faction of 2.% relative to the triblock or the totalPtBA (hPtBA and PtBA block) volume fraction of 0.4., hPtBA and PtBA formed a seemingly continuous phase in the matrixof PCEMA and Pl. Such a block segregation pattern was locked in by photocrosslinking the PCEMA domain. Nanochannelswere formed by extracting out hPtBA with solvent. Alternatively. larger channels were obtained from extracting out hPtBAand hydrolyzing the t-butyl groups of the PtBA block. Such membranes were not liquid permeable but had gas permeabilityconstants ～6 orders of magnitude higher than that of low-density polyethylene films.

关键词： Nanostructures Block copolymers Nanochannel generation Self-Assembly Polyisoprene-b-poly(2.cinnanoylethyl methacrylate)-b-poly(t-butyl acrylate)

Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2. Zhao Hong2.3, Xu Guanjun1,4. Zhu Cuishan2.3, Xiao Tingrong4. Zhang Min2.3 and Zhang Bin1,4.1. Key Laboratory of Petroleum Geochemistry, China National Petroleum Corporation, Beijing 100083, China 2. Geochemistry department of Yangtze university, Jingzhou 4.4.2., China 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze university, Jingzhou 4.4.2., China 4. Petroleum Geology Central Laboratory, Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry department of Yangtze university Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02.0.58 minutes. Totally 2.6 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4.1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 4.0052. China 2. {4. of Physics, Beijing Normal university, Beijing 100875, China 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 4.0000, China 4. Institute of Modern Physics, Fudan university, Shanghai 2.04.3, China Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of Physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern Physics Fudan University Shanghai 200433 China

34.samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Binding activity of H-Ras is necessary for in vivo inhibition of ASK1 activity

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Cell Research 2004年第2期14卷 148-154页

作者： Jun DU~(1,2.), Shao Hui CAI~(3,4., Zhe SHI~3, Fumihiko NAGASE~1 ~1department of Medical Technology, Nagoya university School of Health Sciences, Aichi 4.1-8673, Japan. ~2.chool of Pharmaceutical Science, Sun Yat-Sen university, Guangzhou, 510089, China. ~3department of Immunology, Nagoya university Graduate and Faculty School of Medicine, Aichi, 4.6-8550, Japan. ~4.ollege of Pharmacy, jinan university, Guangzhou, 510632. China. 2.chool of Pharmaceutical Science Sun Yat-Sen University Guangzhou 510089 China. 4.ollege of Pharmacy Jinan University Guangzhou 510632 China. 3department of Immunology Nagoya University Graduate and Faculty School of Medicine Aichi 466-8550 Japan. 1department of Medical Technology Nagoya University School of Health Sciences Aichi 461-8673 Japan.

H-Ras is well known as one of the essential components of Ras/Raf/MEK/ERK cascade, which is a critical prosurvival signaling mechanism in most eukaryotic cells. Ras targets Raf/MEK/ERK cascade by integrating and transmitting extracellular signals from growth factor receptors to Raf, leading to the propagation of signals to modulate a serious of cellular survival events. Apoptosis signal-regulating kinasel (ASK1) serves as a general mediator of cell death because it is responsive to a variety of death signals. In this study, we found that H-Ras interacted with ASK1 to cause the inhibition of both ASK1 activity and ASK1-induced apoptosis in vivo, which was reversed only partially by addition of RafS62.A, an antagonist of Raf, whereas MEK inhibitor, PD98059, and PI3K inhibitor, LY2.4.02. did not disturb the inhibitory effect of H-Ras on ASK-1-induced apoptosis. Furthermore, by means of immunoprecipitate and kinase assays, we demonstrated that the interaction between H-Ras and ASK1 as well as the inhibition

关键词： H-Ras ASK1 apoptosis binding activity.