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Synthesis of lateral macrobicyclic cryptand

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Chinese Journal of Chemistry 1983年第1期1卷 67-70页

作者： J.M.LEHN WU Cheng-tai P.PLUMERE Le Bel Institute,Louis Pasteur University,Strasbourg,France Department of Chemistry,wuhan University,wuhan,{2.. Le Bel Institute Louis Pasteur University Strasbourg France

This paper deals with the synthesis of a new lateral macrobicyclic cryptand ***-tion of 2.6-di（bromomethyl）pyridine with 3-（n-tosylamino）methyl propionate in the presence ofanhydrous KCOat room temperature gave 5 which was hydrolyzed to *** of the latter withexcess sulfonyl chloride afforded 2.6-di（4’-chloroformyl-2.-tosyl-2.-azabutyl）pyridine（7）.Pentaaza-1,5,13,17,2.-dithia-2.,2.-tricyclo[15,5,5,1]-octacosa-7,9,11（2.）-triene（10）has been synthesized bythe following sequence of reactions:Condensation of 7 with 1,7-diaza-4,10-dithia-dodecane（3）by highdilution technique in toluene-THF at room femperature afforded 8 which was reduced by diboranein THF solution to give *** of 9 with sodium anthracene in monoglyme produced 10.

关键词： Synthesis of lateral macrobicyclic cryptand

(5R)-5-hydroxytriptolide inhibits IFN-γ-related signaling

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Acta Pharmacologica Sinica 2006年第12期27卷 1616-1621页

作者： Ru ZHOU~2.Jun-xia WANG~2.Wei TANG~2.Pei-lan HE~2.Yi-fu YANG~2.Yuan-chao LI~3 Xiao-yu LI~2.Jian-ping ZUO~(2.4)2.Laboratory of Immunopharmacology and 3 Laboratory of Chemistry,State Key Laboratory of Drug Research,Shanghai Institute of Materia Medica,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 2.12.3,china Laboratory of Immunopharmacology State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Laboratory of Chemistry State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Aim:(5R)-5-hydroxytriptolide(LLDT-8)displayed anti-arthritis and anti-allogenictransplantation rejection activities in our previous ***,we aim to furtherclarify the effect of LLDT-8 on the pro-inflammatory cytokine IFN-γ.Methods:Tcells were activated with anti-CD3 antibody or concanavalin A(ConA).The ex-pression of cell surface molecules was detected with flow *** werelabeled with carboxyfluorescein diacetate succinimidyl ester(CFSE)to test ***-γ production was determined by enzyme-linked *** proliferation was evaluated by[~3H]-thymidine *** wereimmunized with ovalbumin to assess the in vivo immune ***-PCR andReal-time PCR were applied to determine the mRNA *** protein phos-phorylation levels were detected by Western immunoblot ***:LLDT-8 at 100 nmol/L did not change the CD2.,CD69,and CD154 expressions in anti-CD3-stimulated T ***-8 markedly blocked the cell division of CD4 andCD8 T cells after ConA ***-8 inhibited T cell-derived IFN-γ***,LLDT-8 suppressed the ovalbumin-specific T cell prolif-eration and IFN-γ *** anti-CD3-activated T cells,LLDT-8 abrogated themRNA expression of signal transducer and activator of transcriptionl(STAT1),T-box transcription factor,IL-12.receptor β2.STAT4,and interferon regulatory fac-tor 1 in the IFN-γ expression *** blot analysis showed that LLDT-8 blocked the phosphorylation levels of extracellular signal-regulated kinase,stress-activated protein kinase(SAPK)/c-Jun N-terminal kinase,and p38 mitogen-activated protein kinase in anti-CD3 plus anti-CD2.-activated T *** addition,LLDT-8 reduced the transcripts of macrophage inflammatory protein(Mip)-1α,Mip-1β,regulated upon activation normally T-cell expressed and secreted,induc-ible protein-10,IFN-inducible T cell a chemoattractant,and monokine induced byIFN-7 in IFN-γ-stimulated murine macrophage cell line Raw 2.4.7 ***:LLD

关键词： (5R)-5-hydroxytriptolide IFN-γ MAPK chemokine

Impact of nuclear actin on the prophase chromosome construction of Physarum polycephalum

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Progress in Natural Science:Materials International 2004年第9期 37-41页

作者： JING Yuqi 1, WANG Xiaoguang 2. HAO Shui 1 and ZENG Xianlu 1*(1. Institute of Genetics and Cytology, Northeast Normal University, Changchun 13002., china 2. Department of Biology, Changchun Normal College, Changchun 130032. china) Institute of Genetics and Cytology Northeast Normal University Changchun 130024 China Department of Biology Changchun Normal College Changchun 130032 China

A cell free system efficiently promoting mitosis has been developed using the precise natural synchronous plasmodium of Physarum polycephalum . The content changes of nuclear cyclin B were exploited to represent the prophase process of Physarum polycephalum . The possible function of nuclear actin on chromosome construction was investigated by detecting the content changes of nuclear cyclin B in the late G 2.phase nuclei treated with cytochalasin B and incubated in the cell free system. Our results showed that nuclear actin plays an important role in the process of the chromosome construction.

关键词： Physarum polycephalum nuclear actin chromosome construction cyclin B cell-free system.

Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3D scattering

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Science in china(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2.3 & SHENG XinQing2.1 Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, china 2.Department of Electronic Engineering, Beijing Institute of Technology, Beijing 100081, china 3 Graduated University of Chinese Academy of Sciences, Beijing 100039, china Institute of Electronics Chinese Academy of Sciences Beijing China Department of Electronic Engineering Beijing Institute of Technology Beijing China Graduated University of Chinese Academy of Sciences Beijing China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

Experimental study on the effect of gaseous and particulate emission from an ethanol fumigated diesel engine

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Science china(Technological Sciences) 2010年第12期53卷 3294-3301页

作者： YAO ChunDe1, ZHANG ZhiHui1,2. CHEUNG ChenShun2.& XU GuangLan1 1 State Key Laboratory of Engines, Tianjin University, Tianjin 300072. china 2.Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, china State Key Laboratory of Engines Tianjin University Tianjin China Department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

Experiments were conducted on a four-cylinder direct-injection diesel engine with 10% and 2.% of the engine load taken up by fumigation ethanol injected into the air intake of each cylinder, to investigate the gaseous, particulate mass (PM) emissions, and number concentration and size distribution of the engine under five engine loads at the maximum torque engine speed of 1800 r/min. The experimental results show that at low engine loads, the brake thermal efficiency (BTE) decreases with increase in fumigation ethanol; but at high engine loads, the BTE is not significantly changed by fumigation ethanol. Fumigation ethanol can effectively decrease in brake specific nitrogen oxides (BSNOx), particulate mass and number emissions but significantly increase in brake specific hydrocarbon (BSHC), brake specific carbon monoxide (BSCO) and proportion of BSNO/BSNO2. Also, the geometrical mean diameter of the particles (GMD) increases with increase in engine load but the diameter is not changed by fumigation ethanol in all cases.

关键词： diesel engine ethanol particulate number emissions

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鱼类性别决定的遗传基础研究概况

水产学报 2003年第2期27卷 169-176页

作者：童金苟朱嘉濠关海山中国科学院水生生物研究所香港中文大学生物系香港中文大学生物系湖北武汉　4.0072 中国香港

As lower vertebrates, fishes have complex modes of sex determination. From the cytogenetic perspective, only a small proportion of fish species have heteromorphic sex chromosomes. At the present stage sex determination can only be explained via 'genetics' rather than 'genes' in most species. Nevertheless, genes associated with sex determination and male development were identified in a model fish medaka, Oryzias latipes. Sequences or genetic markers specific to certain sex chromosomes were reported in some fishes. These findings lay the groundwork for further studies on the function and regulation of sex genes aiming at elucidation of the mechanism of sex determination, and provide potential tool for sexing fish. In this minireview, progress in the past few decades in both cytogenetic and molecular genetic studies on sex determination of fish were summarized. Prospects, significance and possible future directions of the studies on fish sex determination were also discussed.

关键词：鱼类性别决定性染色体遗传基础

A DESIGN OF THE PARALLEL FILTER BASED ON WAVELETS

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Acta Mathematica Scientia 1995年第S1期15卷 133-138页

作者：肖文辉陈莘萌 Dept. of computer Science Wuhan University Wuhan 430072 China

The paper designs a parallel filter based on wavelets theory,a design algorithm of parallel wavelet filter is given and proved. The filter is composed of sampler, prefilter, analyser,frequency subsection processor and synthesizer,the principle of the filter is discussed in detail. The design can be applied in the field which need time-frequency localization.

关键词： Wavelet analysis Principle of filter. Design

Two-Parameter Banach Space Valued Strong Martingales and Characterizations of p-Smoothable Spaces

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wuhan University Journal of Natural Sciences 1999年第4期4卷 387-392页

作者： Gan Shi-xin Ye Chen Zhang Feng wuhan University College of Mathematics and Computer Science Wuhan China (GRID:grid.49470.3e) (ISNI:***)

In this paper we introduce the concept of two-parameterB-valued strong martingales and investigate some features of these strong martingales. We also characterizep-smoothable Banach spaces in terms of these strong mar... 详细信息

关键词： two-parameterB-valued strong martingale atomic decomposition p-smoothable

Influence of MnO_2.on the photocatalytic activity of P-2. TiO_2.in the degradation of methyl orange

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中国科学：化学英文版 2008年第2期51卷 179-185页

作者： LI ShunJun1, MA ZiChuan1,2. WANG Lin1 & LIU JingZe2.1 College of Chemistry and Material Sciences, Hebei Normal University, Shijiazhuang 050016, china 2.College of Life Science, Hebei Normal University, Shijiazhuang 050016, china College of Chemistry and Material Sciences Hebei Normal University Shijiazhuang China College of Life Science Hebei Normal University Shijiazhuang China

Influences of α-MnO2. β-MnO2. and δ-MnO2.on the photocatalytic activity of Degussa P-2. TiO2.have been investigated through the photocatalytic degradation of methyl orange. The TiO2.photocatalyst, before and after being contaminated by MnO2. was characterized by UV-visible diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS). The results showed that photocatalytic activity of TiO2.could be inhibited significantly or completely deactivated due to the presence of even a small amount of MnO2.particles. It was found that the poisoning effect varied with the crystal phases of MnO2.and the effect was in the order δ-MnO2.>α-MnO2.>β-MnO2. The poisoning effect was attributed to the formation of heterojunctions between MnO2.and TiO2.particles. The heterojunctions changed the chemical state of Ti4+ and O2.sites in the crystalline phase of TiO2. MnO2.in contact with TiO2.particles also broadens the band-gap of TiO2. which decreases UV absorption of TiO2. It can also create some deep impurity energy levels serving as photoelec-tron-photohole recombination center, which accelerates the electron-hole recombination.

关键词： TiO2 MnO2 deactivation photocatalysis methyl orange