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Formation of surface-attached microstructured polyelectrolyte brushes

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Chinese Chemical Letters 2008年第8期19卷 988-991页

作者： hai ning Zhang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Surface-attached micropattemed polyelectrolyte brushes on planar solid surfaces are generated using free radical polymerization photo-initiated by self-assembled initiator monolayers. It is shown that the formed patte... 详细信息

关键词： Microstructure Self-assembly Surface-initiated polymerization Polyelectrolyte brush

Fractional Schrodinger Equations with Logarithmic and Critical Nonlinearities

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Acta Mathematica Sinica,English Series 2023年第2期39卷 285-325页

作者： hai ning FAN Bin Lin ZHANG School of Mathematics China University of Mining and TechnologyXuzhou221116China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China

In this paper,we study a class of the fractional Schrodinger equations involving logarithmic and critical *** using the Nehari manifold method and the concentration compactness principle,we show that the above problem admits at least one ground state solution and one ground state sign-changing ***,by using variational methods,we prove that how the coefficient function of the critical nonlinearity affects the number of positive *** main feature which distinguishes this paper from other related works lies in the fact that it is the first attempt to study the existence and multiplicity for the above problem involving both logarithmic and critical nonlinearities.

关键词： Logarithmic nonlinearity critical Sobolev exponent fractional Schr?dinger equation ground state solution sign-changing solution

Classification of stellar populations in globular clusters

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Research in Astronomy and Astrophysics 2017年第5期17卷 107-112页

作者： Yue Wang Gang Zhao hai-ning Li Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences

Possessing multiple stellar populations has been accepted as a common feature of globular clusters（GCs）. Different stellar populations manifest themselves with different chemical features,e.g. the well-known O-Na anti-correlation. Generally, the first（primordial） population has O and Na abundances consistent with those of field stars with similar metallicity; while the second（polluted） population is identified by their Na overabundance and O deficiency. The fraction of the populations is an important constraint on the GC formation scenario. Several methods have been proposed for the classification of GC populations. Here we examine a criterion derived based on the distribution of Galactic field stars, which relies on Na abundance as a function of [Fe/H], to distinguish first and second stellar populations in GCs. By comparing the first population fractions of 17 GCs estimated by the field star criterion with those in the literature derived by methods related to individual GCs, we find that the field star criterion tends to overestimate the first population fractions. The population separation methods,which are related to an individual GC sample, are recommended because the diversity of GCs can be taken into consideration. Currently, more caution should be exercised if one wants to regard field stars as a reference for the identification of a GC population. However, further study on the connection between field stars and GCs populations is still needed.

关键词： stellar populations stars criterion distinguish scenario primordial abundance manifest constraint

Achene Wall Anatomy and Surface Sculpturing of Lactuca L. and Related Genera （Compositae： Lactuceae） with Notes on Their Systematic Significance

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Journal of Integrative Plant Biology 2006年第4期48卷 390-399页

作者： Shi-Xin Zhu hai-ning Qin Chu Shih Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Bioengineering Department Zhengzhou University Zhengzhou 450001 China

The achene wail anatomy and surface sculpturing of 14 species representing Lactuca L. and related genera were Investigated to evaluate inter-and Intrageneric relationships. The achene wall anatomy of the studied species can be divided Into two types： winged and ribbed. The winged type is present in Lactuca L., Pterocypsela Shlh, Clcerblta Wallr., Chaetoserls Shlh and Stenoseris Shlh, and is characterized by protruding wings and costae in transverse section. Winged type achene mesocarps are composed of parenchymatous cells and fiber ceils, and the distinct fibrous strands are confined to the costae or wings of the achenes. The ribbed type is present in Notoseris Shih and Paraprenanthes Chang ex Shih, and Is characterized by only having costae In transverse section. Fiber cells are continuous in the costae and intercostae, in surface sculpturing, the ornamentation and the shape of epidermal cells are different among these genera. The results Indicate that L. altalca and L. serrlola should be conspeclfic, and that L. dollchophylla is probably an Intermediate taxon between Lactuca and Chaetoserls. The results also support the separation of Pterocypseia, Paraprenanthes, Notoseris, Chaetoseris and Stenoserls from Lactuca and Clcerblta as independent entitles. Close affinities between Pterocypsela and Lactuca, Paraprenanthes and Notoserls, and Chaetoserls and Stenoserls are also proposed.

关键词： achene structure Compositae Lactuca Lactuceae surface sculpturing systematics.

Isothermal Crystallization Kinetics and Crystalline Morphologies of Poly(butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate)Copolymers

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Chinese Journal of Polymer Science 2018年第6期36卷 756-764页

作者： Fei Liu De-Quan Chi hai-ning Na Jin Zhu ningbo Key Laboratory of Polymer Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China

In this study, the isothermal crystallization kinetics and crystalline morphology of poly（butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate）（PBAC）, which refers to a copolyester containing a non-planar ring structure, were investigated by differential scanning calorimetry and polarized optical microscopy, and compared with those of neat poly（butylene 1,4-cyclohexanedicarboxylate）（PBC）. The results indicate that the introduction of butylene adipate（BA） unit into PBAC did not change the intrinsical crystallization mechanism. But, the crystallization rate and ability, and equilibrium melting temperature of PBAC copolymers were reduced. All PBC and PBAC copolymers could only form high density of nucleation from melt at given supercooling, while no Maltese cross or ring-banded spherulites could be observed. PBAC copolymers with a high amount of BA unit became amorphous after quenching with liquid nitrogen from melt, while PBC and PBAC copolymers with a low amount of BA unit could still form a large amount of nuclei under the same treatment.

关键词： Poly(butylene adipate-co-butylene 1 4-cyclohexanedicarboxylate) Isothermal crystallization kinetics Crystalline morphology

Photophysical Behavior of Heteroduplexes Formed from Naphthalene Incorporated Foldamers,and Linear Donors and Pyromellitic Diimide Incorporated Foldamers

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Chemical Research in Chinese Universities 2009年第3期25卷 317-327页

作者： ZHAO Shu-min GU hai-ning ZHOU Qi-zhong Key Laboratory for Molecular Design and Nutrition Engineering of ningbo Ningbo Institute of Technology of Zhejiang University Ningbo 315100 P. R. China Department of Chemistry Zhejiang University Hangzhou 310027 P. R. China

The authors synthesized the electron-rich 1,5-dioxonaphthyl group incorporated foldamers, and linear donors and electron-deficient pyromellitic diimide incorporated foldamers, which were investigated in organic solvents. There is an evident charge transfer process from the donors to the electron-deficient foldamers, due to the donor-acceptor interaction of the heteroduplexes formed from the donors and the electron-deficient foldamers in chloroform, observed by using the ultraviolet（UV） visible method. The charge transfer process of the heteroduplexes depends on the molecular structure（not only the number of 1,5-dioxonaphthyl groups and pyromellitic diimide groups in the heteroduplex, but also the intermolecular double hydrogen bond in the heteroduplex）, the intercalative π-π stacking motif, the initial concentration of heteroduplexes, and the polarity of the solvent. Fortunately, the authors found a critical bumping concentration（CBC） of the donors in acetonitrile or chloroform, which is useful in quantitative research, by using the fluorescence method. The value of CBC depends not only on intramolecular folding and the intramolecular hydrogen bond, but also on intramolecular π-π stacking and the solvent. The electron-deficient foldamers quenched the fluorescence of the donors. Fluorescence quenching depends not only on the number of pyromellitic diimide groups and 1,5-dioxonaphthyl groups in the heteroduplex, but also on the intercalative π-π stacking motif between the donor and the acceptor.

关键词： Heteroduplex Foldarner Linear donor Charge transfer Quench

Coordination-driven self-assembly of a molecular 818knot and molecular borromean rings

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Science China Chemistry 2024年第11期67卷 3652-3656页

作者： Xiang Gao Dong Liu hai-ning Zhang Guo-Xin Jin Department of Chemistry Fudan UniversityShanghai 200433China

We report the facile construction of a molecular 8_(18) knot and a molecular Borromean rings assembly through self-assembly directed by Cp^(*)Rh corner units. Two curved ligands of similar size and shape were used in this study. The slight steric differences between the two ligands induce the formation of distinctly different topologies of the assembled products. The structures were confirmed by single-crystal X-ray analysis and nuclear magnetic resonance spectroscopy.

关键词： coordination-driven Cp^(*)Rh 8_(18)knot Borromean rings

Hydrodynamic performance of flexible risers subject to vortex-induced vibrations

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Journal of Hydrodynamics 2013年第1期25卷 156-164页

作者： ZHANG Hui YANG Jian-min XIAO Long-fei LU hai-ning State Key Laboratory of Ocean Engineering Shanghai Jiaotong University

The Vortex-Induced Vibration （VIV） displacements are determined from both the measured accelerations and strains in a series of VIV experiments. Based on the results, the forces in the longitudinal, transversal and tangential directions are estimated by using the finite element method with and without considering the interactions between adjacent elements. The numerical simulation indicates that the method considering the interactions performs better in the estimation of the forces. The component of the transversal force in phase with the acceleration is associated with the added mass coefficient. The estimated added mass coefficients take abnormally high values at the locations where the displacements are small. An improved formula based on the L＇Hospital＇s rule is pro- posed to deal with this problem. The results show the advantage of this formula in estimating the added mass coefficients at the loca- tions with small VIV displacements.

关键词： Vortex-Induced Vibration (VIV) flexible risers hydrodynamic force added mass coefficient

Ion sulphuration-an effective surface engineering technique for reducing friction and wear of rubbing-pairs

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中国有色金属学会会刊：英文版 2004年第z1期14卷 13-18页

作者： LIU Jia-jun WANG hai-dou ZHANG ning ZHANG Da-ming Department of Mechanical Engineering Tsinghua University Beijing 100084 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China Chinergy Co. Ltd. Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The low temperature ion sulphuration-an effective surface engineering technique for reducing friction and wear of rubbing-pairs was introduced. It involves the principle of ion sulphuration process, microstructure of FeS film on 1045 steel, tribological properties of FeS film on steels, microstructions and tribological properties of MoS2 and nano-FeS/MoS2 multi-layered films, as well as their applications.

关键词： solid lubrication low temperature ion sulphuration friction and wear surface engineering