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The adsorption isotherms, IR and ^(29)Si MAS NMR spectra of modified MCM-41 molecular sieves

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Chinese Science Bulletin 1997年第10期42卷 828-832页

作者： LONG Yingcai, DONG Weiyang, XU Taiming, GAO Xiaoqin, XIE Guangen and SUN Yaojun1. Department of Chemistry, fudan university, shanghai 2.043., china 2. Centre of Analysis and Measurement, fudan university, shanghai 2.043., china Department of Chemistry Fudan University Shanghai China Centre of Analysis and Measurement Fudan University Shanghai China

RECENTLY a new family of mesoporous molecular sieves,M41S,was reported by researchers atMobil R&D *** a member of the family,MCM-41,which exhibits a hexagonalarray of uniform channel mesopores,has been *** channel size can be variedfrom approximately 1.5 nm to greater than 10 nm by choosing different surfactants,auxiliarychemicals(1,3,5-trimethylbenzene)in the reactant,and by changing the reaction *** wall thickness of this kind of molecular sieve is in the range of 0.3 to 1.3 nm esti-

关键词： MCM-41 surface modification adsorption isotherm IR 29Si MAS NMR.

Ultrafast excitation relaxation in light-harvesting complex LH2 from *** 601

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Science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2, LIU Yuan3, LIU Weimin2, GUO Junhua1, XU Chunhe3 & QIAN Shixiong2 1. school of Physics and Information Optoelectronics, Henan university, Kaifeng 475001, china 2. Physics Department, fudan university, shanghai 2.043., china 3. shanghai Institute of Plant Physiology, Chinese Academy of sciences, shanghai 200032, china 1. school of Physics and Information Optoelectronics Henan University 475001 Kaifeng China 2. Physics Department Fudan University 200433 Shanghai China 3. shanghai Institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2 from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783 nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.35 ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

A HYPERBOLIC SYSTEM OF CONSERVATION LAWS FOR FLUID FLOWS THROUGH COMPLIANT AXISYMMETRIC VESSELS

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Acta Mathematica Scientia 2010年第2期30卷 391-427页

作者： Gui-Qiang G.Chen school of mathematical sciences,fudan university,shanghai 2.043.,china.mathematical Institute,university of Oxford,24-29 St Giles,Oxford,OX1 3LB,UK Department of Mathematics,Northwestern university,Evanston,IL 60208-2730,USA Weihua Ruan Department of Mathematics,Computer Science and Statistics,Purdue university Calumet,Hammond,IN 46323-2094,USA [a] school of mathematical sciences Fudan University Shanghai 200433 China [b] Mathematical Institute University of Oxford 24-29 St Giles Oxford OX1 3LB UK [c] Department of Mathematics Northwestern University Evanston IL 60208-2730 USA [d] Department of Mathematics Computer Science Statistics Purdue University Calumet Hammond IN 46323-2094 USA

We are concerned with the derivation and analysis of one-dimensional hyperbolic systems of conservation laws modelling fluid flows such as the blood flow through compliant axisyminetric vessels. Early models derived are nonconservative and/or nonho- mogeneous with measure source terms, which are endowed with infinitely many Riemann solutions for some Riemann data. In this paper, we derive a one-dimensional hyperbolic system that is conservative and homogeneous. Moreover, there exists a unique global Riemann solution for the Riemann problem for two vessels with arbitrarily large Riemann data, under a natural stability entropy criterion. The Riemann solutions may consist of four waves for some cases. The system can also be written as a 3 × 3 system for which strict hyperbolicity fails and the standing waves can be regarded as the contact discontinuities corresponding to the second family with zero eigenvalue.

关键词： conservation laws hyperbolic system fluid flow blood flow vessel hyper-bolicity Riemann problem Riemann solution wave curve shock wave rarefaction wave standing wave stability

A meta-analysis of oxidative stress markers in schizophrenia

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中国科学：生命科学英文版 2010年第1期53卷 112-124页

作者： ZHANG Ming1,2,ZHAO ZhongMing3,HE Lin1,2,4 & WAN ChunLing1,2 1 Bio-X Center,Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education),shanghai Jiao Tong university,shanghai 200030,china.2 Institutes for Nutritional sciences,shanghai Institute of Biological sciences,Chinese Academy of sciences,shanghai 200031,china.3 Departments of Biomedical Informatics,Psychiatry,and Cancer Biology,Vanderbilt university Medical Center,Nashville,TN 37232,USA 4 Institutes of Biomedical sciences,fudan university,shanghai 200032,china 1. Bio-X Center Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) Shanghai Jiao Tong University Shanghai 200030 China2. Institutes for Nutritional Sciences Shanghai Institute of Biological Sciences Chinese Academy of Sciences Shanghai 200031 China3. Departments of Biomedical Informatics Psychiatry and Cancer Biology Vanderbilt University Medical Center Nashville TN 37232 USA4. Institutes of Biomedical Sciences Fudan University Shanghai 200032 China

Oxidative stress has been identified as a possible element in the neuropathological processes of schizophrenia(SCZ).Alteration of oxidative stress markers has been reported in SCZ studies,but with inconsistent *** evaluate the risk of oxidative stress to schizophrenia,a meta-analysis was conducted,including five markers of oxidative stress [thiobarbituric reactive substances(TBARS),nitric oxide(NO),catalase(CAT),glutathione peroxidase(GP) and superoxide dismutase(SOD)] in SCZ patients versus healthy *** study showed that TBARS and NO significantly increased in SCZ,while SOD activity significantly decreased in the disorganized type of SCZ *** significant effect size was found for the activities of GP and CAT in SCZ patients(P>0.05).Egger’s regression test observed no significant publication bias across the oxidative stress markers,but found high heterogeneities in all the 5 *** subgroup analysis suggested that the ethnicity,sample size of patients and sample sources may contribute to the heterogeneity of the results for TBARS,NO and *** result further demonstrated the involvement of oxidative stress in the pathophysiology of schizophrenia.

关键词： schizophrenia oxidative stress meta-analysis lipid peroxidation nitric oxide antioxidant enzymes

Experimental Study on Turbulent Structure of Humid Air Flame in a Bluff-body Burner

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Journal of Thermal Science 2009年第2期18卷 185-192页

作者： Bing Ge Shu-Sheng Zang Pei-qing Guo school of Mechanical Engineering, shanghai Jiao Tong university, shanghai 200240, china 800, Dong Chuan Road, shanghai, china. Zip: 200240 school of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China 800 Dong Chuan Road Shanghai China Zip: 200240

The main objective of the present experimental study is to analyze the turbulent structure in humid airnon-premixed flame, and determine the effect of humidity on the flow field and the flame stability limit in turbulentnon-premixed flame. Particle Image Velocimetry (PIV) is used to capture the instantaneous appearance ofvortex structures and obtain the quantitative velocity field. The distributions of Reynolds shear stress, mean androot-mean squared fluctuating (rms) velocities are examined to get insight into the effect of fuel-to-air velocity ratioon velocity flow field. The results show that with steam addition, the air-driven vortex in the bluff-body wakeis thinner; the biggest peaks of rms velocity and Reynolds shear stress are lower; the distance between the peaksof rms velocity on the sides of centerline reduces. Besides these, the flame stability is affected. Both central fuelpenetration limit and partially quenching limit reduce with steam addition.

关键词： humid air combustion turbulence measurement PIV

Synthesis and Characteristics of an Aspartame Analogue,L-Asparaginyl L-3-Phenyllactic Acid Methyl Ester

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 385-389页

作者： Hu TAO1, Da-Fu CUI1, and You-Shang ZHANG1,2* 1Institute of Biochemistry and Cell Biology, shanghai Institutes for Biological sciences, Chinese Academy of sciences, Graduate school of the Chinese Academy of sciences, shanghai 200031, china Institute of Protein Research, Tongji university, shanghai 200031, china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China Institute of Protein Research Tongji UniversityShanghai 200031 China

An aspartame analogue, L-asparaginyl L-3-phenyllactic acid methyl ester was synthesized with aspartic acid replaced by asparagine and peptide bond replaced by ester bond. The aspartic acid of aspartame could be replaced by asparagine as reported in the literature. In this analogue, the hydrogen of amide group could still form a hydrogen bond with the oxygen of ester bond and the ester bond was isosteric with peptide bond. However, the product was not sweet, showing that the peptide bond could not be replaced by ester bond. The peptide C-N bond behaves as a double bond that is not free to rotate and the C, O, N and H atoms are in the same plane. The replacement of peptide bond by ester bond destroyed the unique conformation of peptide bond, resulting in the loss of sweet taste.

关键词： artificial sweetener aspartame derivative peptide bond

Influence of Mo on the microstructure and mechanical properties of TiC-based cermets

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Rare Metals 2010年第4期29卷 346-350页

作者： WANG Xingqing,HE Xiaoxiang,and GUO Hailiang school of Materials Science and Engineering,shanghai university,shanghai 200072,china school of Materials Science and Engineering Shanghai University Shanghai China

The microstructures and mechanics properties of TiC-based cermets composed of TiC, WC, Ni, Co, Mo, and Cr3C2 were investigated. The results show that Mo has a great effect on the sintering densification, microstructures, and mechanical properties. The microstructures and distribution of Mo and Ti in the TiC-based cermets were analyzed. It was indicated that a new phase with Ti, Mo, W, and C was formed on the rim of （Ti,W）C grains by means of an addition of Mo into the TiC-based cermets. The new phase with a surrounding structure was of great aid to improve the wettability of the liquid phase on the solid phase surface of TiC, decrease the porosity and refine the grains of the hard phase, which gave rise to the increase in strength and hardness. The properties of the TiC-based cermets could be further improved to some extent by adding WC, Cr2C3, and Co.

关键词： TiC-based cermets Mo effect sintering densification microstructure mechanical properties

ON LINEAR AND NONLINEAR RIEMANN-HILBERT PROBLEMS FOR REGULAR FUNCTION WITH VALUES IN A CLIFFORD ALGEBRA

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Chinese Annals of Mathematics,Series B 1990年第3期11卷 349-357页

作者：徐振远 Department of Mathematics Fudan University

This paper deals with the boundary value problems for regular function with valuesin a Clifford algebra: （）W=O, x∈Rn\Г, w+（x）=G（x）W-（x）+λf（x, W+（x）, W-（x））, x∈Г; W-（∞）=0,where Г is a Liapunov surface in Rn the differential operator （）=（）/（）x1+（）/（）x2+…+（）/（）xnen, W（x） =∑A, （）AWA（x） are unknown functions with values in a Clifford algebra （）n Undersome hypotheses, it is proved that the linear baundary value problem （where λf（x, W+（x）,W-（x）） =g（x）） has a unique solution and the nonlinear boundary value problem has atleast one solution.

关键词： algebra Liapunov deals Liouville Riemann erior lying 二七云一耐公

A Resistivity Gradient Piezoelectric FGM Actuator

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Journal of Materials Science & Technology 2000年第4期16卷 383-386页

作者： S. U.Adikary and Zhongyan MENG (school of Materials Science and Engineering, shanghai university, shanghai 201800, china) Dengren JIN (school of Materials Science and Engineering, shanghai Jiaotong university, shanghai 200030, china) school of Materials Science and Engineering Shanghai University Shanghai 201800 China school of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China

A resistivity gradient actuator based on lead zirconate titanate ceramics was successfully developed and the bending deflections up to 140 μm were obtained. The actuator material was a matrix of PZT ceramic into which smooth gradient of piezoelectric activity was introduced. The application of an electric field then causes the actuator to bend due to differential strains induced by the piezoelectric effect. The resistivity gradient of the actuator was achieved by doping PZT with suitable donor and acceptor dopants. PZT powder was modified and synthesized by using two stage powder fabrication method. The actuator was fabricated by uniaxial pressing followedby isostatic pressing with two layers of different resistivities.

关键词： PZT FGM