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THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

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Chinese Journal of Polymer Science 2003年第2期21卷 117-122页

作者： Chi Wu The Open laboratory of Bond Selective Chemistry Department of chemical Physics, University of Science and Technology of China, hefei 23.026 China Department of Chemistry The Chinese University of Hong Kong Shatin, Hong Kong University of Science and Technology of China Laboratory of Bond Selective Chemistry CAS Hefei 230026

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute *** formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.

关键词： Viscoelasticity Mesoglobular phase Heteropolymer Nanoparticle Polymer Dispersion Microphase inversion

Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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Science China Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2, ZHANG Lide1, ZHENG Jiyong2, FU Shangang3.& ZHU Mingwei3.1. Institute of Solid State Physics, Chinese Academy of Sciences, hefei 23.03., China 2. Luoyang Ship Material Research Institute, Luoyang 47103., China 3. College of Life Science, Henan Normal University, Xinxiang 453.02, China Institute of Solid State Physics Chinese Academy of Sciences Hefei China Luoyang Ship Material Research Institute Luoyang China College of Life Science Henan Normal University Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

A HYBRID POLYMER GEL AND ITS STATIC NONERGODICITY

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Chinese Journal of Polymer Science 2002年第3期20卷 269-274页

作者： Yue Zhao Chi Wu The Open laboratory of Bond Selective Chemistry Department of chemical Physics, University of Science and Technology of China hefei 23.026 China Department of Chemistry The Chinese University of Hong Kong Shatin, N.T., Hong Kong China Open Lab. of Bond Selective Chem. Department of Chemical Physics Univ. of Sci. and Technol. of China Hefei 230026 China

We used a thermally reversible hybrid gel made of billions of physically jam-packed swollen thermally sensitivepoly(N-isopropyl-acrylamide) chemical microgels. Laser light scattering study on a series of such hybrid gels formed atdifferent gelling rates and temperatures revealed that the position-dependence of the scattering speckle pattern(staticnonergodicity) came from large voids formed during the sol-gel transition. With a proper preparation, such a nonergodicitycould be completely removed, indicating that the static nonergodicity generally observed in a gel is not indinsic, but comesfrom the clustering "island" structure formed during the gelation process.

关键词： Polymer gel Nonergodicity Dynamic light scattering

Adsorption and Reaction of CO on Mo(100)-c(2×2)-N Surface Studied by HREELS

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Chinese chemical Letters 2000年第3期11卷 275-278页

作者： Jun Fa ZHU.,ian Chang GUO, Run Sheng ZHAI, Xin He BAO, Shu Xian ZHUANG ( National Synchrotron Radiation laboratory, University of Science and Technology of China, hefei 23.029 Department of chemical Physics. University of Science and Technology of China Natl. Synchrt. Radiation laboratory Univ. of Sci. and Technol. of China Hefei 230029 China State Key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Department of chemical Physics Univ. of Sci. and Technol. of China Hefei 230026 China

High resolution electron energy loss spectroscopy (HREELS) has been used to investigate the adsorption and reaction of CO on the Mo(100)-c(2×2)N surface. CO directly adsorbed on the N atoms from the c(2×2) layer to form isocyanate (NCO) surface species was found in addition to CO adsorbed on the molybdenum atoms at 120 K. indicating that both Mo and N atoms of the Mo(100)-c(2×2)-N surface are of high reactivities for CO adsorption.

关键词： HREELS adsorption reaction Mo(100)-c(2×2)-N CO.

New Evidences for the Adsorption of Methane over Oxide Surfaces

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Chinese chemical Letters 1996年第9期7卷 875+873-874页

作者： Fa Qiang XU Shi Kong SHEN Jin Zhen XUE(National Synchrotron Radiation laboratory.University of Science and Technology of China.hefei 23.029.)(Key State laboratory for Oxo Synthesis and Selective Oxidation. Lanzhou Institute of {3. Physics.Chinese Ac Natl. Synchrt. Radiation laboratory Univ. of Sci./Technology of China Hefei 230029 Key State Lab. Oxo Synthesis/S. O. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000

It is indicative of the TSR result that CH4 was strongly adsorbed on well degassed SrCO3.surface at high temperatUre.A desorption peak of CH4 was found in CH4TPD profile which appeared at ca. 3.0℃.The strong adsorption of CH4 over the surface of SrCO3.was attributed to the strong basicity of SrO sites resulted from decomposition of SrCO_3

关键词： over New Evidences for the Adsorption of Methane over Oxide Surfaces

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

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Science China Earth Sciences 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2 & Chi-yuen Wang3.1. Department of Earth Sciences, Nanjing University, State Key laboratory of Mineral Deposit, Nanjing 210093. China 2. Department of Earth and Space Sciences, University of Science and Technology of China, hefei 23.026, China 3. Department of Geology and Geophysics, University of California, Berkeley, CA 94720, USA Department of Earth Sciences Nanjing University State Key Lab. of Mineral Deposit Nanjing 210093 China Dept. of Earth and Space Sciences Univ. of Science/Technology of China Hefei 230026 China Department of Geology and Geophysics University of California Berkeley CA 94720 United States

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.

Synthesis and Structural Characterization of Adduct Cu_2(phen)_2·3.FCA)·(ClO_4)·2H_2O

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Chinese chemical Letters 2000年第7期11卷 639-640页

作者： Jia Xiang YANG YU Peng TIAN Qing Liang LIU Yong Shu XIE Hoong Kun FUN(Department of Chemistry, Anhui University, hefei 23.03.Department of Chemistry, ustc, hefei 23.026 X-ray Crystallography Unit, School of Physics, University Sains Malaysia, 11800 U Department of Chemistry Anhui University Hefei 230039 China Department of Chemistry USTC Hefei 230039 China

A new dinuclcar copper (II) complex containing 3.ferrocenyl-2-crotomic acid salt (FCA)and phen has been synthesized. Its structure was charactcrized by X-ray crystal analysis. The molecular is a pentametallic compound.

关键词： Copper adduct crystal structure

FAILURE ASSESSMENT OF DEFECTIVE GATHERING TUBE UNDER HIGH PRESSURE

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Chinese Journal of Mechanical Engineering 2002年第2期15卷 189-192页

作者： Zhang Wenge Li Jianrong Yu JilinKey laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, CAS, hefei 23.027, ChinaChen Xuedong Zhang Haibo Wang Bing hefei General Machinery Research Institute Mechanical Behavior and Design of Materials University of Science and Technology of China CAS Hefei 230027

A numerical model on stress assessment of a defective elliptic gathering tubeused in the heat recovery boiler of a pyrolyzer is built up. The effect of local defects on thecarrying capacity of the tube is analyzed by using the MSC/NASTRAN finite element code, and thecritical size of defects is obtained. Then, two numerical models of damaged tube with local andintegral reinforcements, respectively, are also calculated. Stress classification and assessmentsare provided by applying the ASME and JB473.-1995 standard. Some guidance and suggestions about thetube reinforcements and the prediction of the remaining life of the structure for engineeringpractice are discussed.

关键词： Gathering tube Heat recovery boiler Initial damage Failure assessment Numerical simulation

Spectrophotometric Investigation of Cadmium Complex Solutionwith m-Bromobenzenediazoaminoazobenzene

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Chinese chemical Letters 1999年第11期10卷 957-960页

作者： Hong Wen GAO Lei WANG Hao YE(School of Chemistry and chemical Engineering, Anhui University, hefei 23.03.)(Department of Chemistry, Huaibei Coal Teachers College, Huaibei 23.000) Sch. of Chem. and Chem. Engineering Anhui University Hefei 230039 China Department of Chemistry Huaibei Coal Teachers College Huaibei 235000 China

The synthesis of a new ligand, m-bromobenzenediazoaminoazobenzene (m-BBDA) was carried out. The reaction between m-BBDA and cadmium(II) was sensitive at pH over 12 and in the presence of emulsifier OP. Because of the high interference of excess of ligand beta-correction theory was applied instead of the single wavelength method. This study gave the simple determination of the complex ratio, real molar absorptivity (epsilon) and step or cumulative stability constant (K).

关键词： beta-correction principle cadmium complex m-bromobenzenediazoaminoazobenzene