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CHOLESTERIC LIQUID CRYSTALLINE CHARACTER ON THE SURFACE OF CHITOSAN/POLYACRYLIC ACID COMPOSITES

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Chinese Journal of Polymer Science 2001年第3期19卷 247-253页

作者： Yan-ming Dong Yu-song wu Mian Wang department of Materials Science & State Key Laboratory for Physical Chemistry of Solid Surfaces, xiamen university xiamen 361005, china 厦门大学固体表面物理化学国家重点实验室福建厦门

The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surface by both scanning electron microscopy (SEM) and atomic force microscopy (AFM), instead of the thumb-print texture which can be detected with polarized optical microscopy. It is suggested that the periodical lamellar-like structure is induced by the etching selectivity between cholesteric layers due to different molecular arrangement on the film surface. Four kinds of perpendicular disclinations, i.e. chi --> tau (-) + lambda (+), chi --> lambda (-) + tau (+), chi --> tau (-) + tau (+) and chi --> lambda (-) + lambda (+) were found in the composite films from SEM observations. The smallest periodicity of lamellar-like structure (equals to half pitch) is 20 similar to 40 nm measured with AFM.

关键词： chitosan cholesteric order liquid crystalline fingerprint texture lamellar structure SEM AFM

Structures and stability of (HAlNH)_n(n=1-15)

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Chinese Science Bulletin 2001年第18期46卷 1507-1514页

作者： wu Haishun, ZHANG Congjie, XU Xiaohong, ZHANG Fuqiang & ZHANG Qianerdepartment of Chemistry, Shanxi Normal university, Linfen 041004, china department of Chemistry, xiamen university, xiamen 361005, china department of Chemistry Shanxi Normal University Linfen China department of Chemistry Xiamen University Xiamen China

The geometries, electronic states, vibrational spectra and thermodynamic properties for (HAINH)n clusters with n=1-15 have been investigated using the ab initio DFT/B3LYP method with basis sets 6-31G* and their ground state structures obtained. Comparison of the (HAINH)n with (A1N)n clusters shows that the skeletons of (HAINH)n consist of four-membered and six-membered rings made of Al-N bonds, and either Al or N atom forms four bonds in which three ones are Al-N bonds and the rest is Al-H or N-H bond. The number of Al-N bonds of (HAINH)n is equal to that of (AlN)n. The magic number regularity of (HAINH)n is n =2, 4, 6, 8, etc., all of which are even numbers.

关键词： DFT method (HAINH)n cluster structure stability.

Square ZnO nano-column and its thermal evolution

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Science china(Technological Sciences) 2010年第2期53卷 309-312页

作者： HUANG BinWang, ZHAN HuaHan, wu YaPing, CHEN XiaoHang & KANG JunYong Key Laboratory of Semiconductor Materials and Applications, department of Physics, xiamen university, xiamen 361005, china Key Laboratory of Semiconductor Materials and Applications Department of Physics Xiamen University Xiamen China

Square ZnO nano-columns have been manufactured by molecular beam epitaxy on p-type Si (100) substrate. The morphology and the evolution sequences after thermal annealing were investigated by in-situ scanning tunneling microscopy. We associated the morphology and microstructure evolution with the cubic Si (100) substrate, large lattice mismatching, the coexistence of wurtzite and zincblende phases of ZnO, and the thermal effect.

关键词： ZnO square nano-column anneal wurtzite phase zincblende phase Si (100)

Density-controlled growth of well-aligned ZnO nanowires using chemical vapor deposition

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Science china(Technological Sciences) 2010年第3期53卷 766-768页

作者： wu ZhiMing,LIN XianGan,HUANG Kai,LI ShuPing&KANG JunYong Key Laboratory of Semiconductors and Applications,department of Physics,xiamen university,xiamen 361005,china Key Laboratory of Semiconductors and Applications Department of Physics Xiamen University Xiamen China

Well-aligned ZnO nanowires were grown on Si substrate by chemical vapor *** experimental results showed that the density of nanowires was related to the heating process and growth ***-density ZnO nanowires were obtain... 详细信息

关键词： density-controlled ZnO nanowires thermal evaporation

Variation of Electronic Structure with C Content in Si_(1-x-y)Ge_xC_y/Si(001) System

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Journal of Materials Science & Technology 1999年第4期15卷 296-298页

作者： Meichun HUANG Liqing wu and Zizhong ZHU(department of Physics, xiamen university, xiamen 361005, china)To whom correspondence should be addressedE-mail: wlq@yanan. xmu. edu. cn department of Physics Xiamen University Xiamen 361005 China

The electronic structures of strained Si 1-x-.Ge. C. (y<0.09) alloys on Si(001) have been studiedby the ab initio pseudopotential method within the local density functionaI theory. The variationsof the minim um band gap. the valence-band offset and the strain properties in the heterojunctioninterface are calculated together with the average bond energy theory. It is found that thedependences of the minimum band gap and the valence-band offset on the alloy compositionchange around the point of zero lattice mismatch. A comparison between our theoreticaf results and the available experimental data indicates that some of the contradictions from differentresearch groups can be reasonably explained.

关键词： Ge x-y)Ge_xC_y/Si System

Optical Microsphere Nano-Imaging:Progress and Challenges

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Engineering 2024年第5期36卷 102-123页

作者： Guangxing wu Minghui Hong department of Electrical and Computer Engineering National University of SingaporeSingapore 117576Singapore Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China

The optical diffraction effect imposes a radical obstacle preventing conventional optical microscopes from achieving an imaging resolution beyond the Abbe diffraction limit and thereby restricting their usage in a multitude of nanoscale *** the past decade,the optical microsphere nanoimaging technique has been demonstrated to be a cost-effective solution for overcoming the diffraction limit and has achieved an imaging resolution of up to about k6k8 in a real-time and label-free manner,making it highly competitive among numerous super-resolution imaging *** this review,we summarize the underlying nano-imaging mechanisms of the microsphere nanoscope and key advancements aimed at imaging performance enhancement:first,to change the working environment or modify the peripheral hardware of a single microsphere nanoscope at the system level;second,to compose the microsphere compound lens;and third,to engineer the geometry or ingredients of *** also analyze challenges yet to be overcome in optical microsphere nano-imaging,followed by an outlook of this technique.

关键词： Microsphere Nano-imaging Virtual imaging Microsphere compound lens Engineered microsphere

Issues on Supply Chain Management

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厦门大学学报（自然科学版） 2002年第S1期41卷 281-282页

作者： wu Shun-xiang, ZHANG Min, CHEN Jian-hui (department of Automation, xiamen university, xiamen 361005, china)

Although supply chain is regarded as an integrated pr ocess, actually, researchers and practitioners have primarily investigated the v arious processes of the supply chain individually. The competitive field in most markets requires well-designed integrated supply chain instead of individual o perations. In this paper, some traditional thinking of supply chain is given fir st, then SCM (Supply Chain Management) is introduced, which views the entire sup ply chain as a whole rather than individual process and aims to increase transpa rency and alignment of the supply chain’s coordination and configuration, regar dless of functional or corporate boundaries. Secondly, issues regarding the significance and the situation of supply chain management in enterprises of Chin a are briefly described. In china, most enterprises haven’t established the ide a of supply chain management, supply chain are just focused on the step from sup pliers to manufacturers, which is a partial but not whole supply chain. Challeng ed by intense competition in the global market, further research on supply chain management is badly needed in china, if not, traditional pattern must be overwh elmed by world competition. Finally, suggestions for future research, especial ly the required conditions for a successful adoption of supply chain managemen t, are outlined. Organizations with Supply chain management can realize the advantages of backward vertical integration. However the following issues must b e paid attention to before supply chain management pattern is established.(1) Ch anging the corporate cultures of all members in the value chain to make it condu cive to supply chain management.(2) Developing long-term, cooperative and certi fied relationship with key suppliers.(3) Developing supply chain management soft ware that includes a completely integrated information system based on distr ibuted database throughout supply chain.(4) Reconstructing organization structur e adapting to supply chain

关键词： supply chain Supply Chain Management (SCM)

A New Group Theoretical Approach to the Nonorthogonal Problem in Valence Bond Theory

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Chemical Research in Chinese Universities 1992年第3期8卷 298-300页

作者： LI Jia-bo and wu Wei (department of Chemistry, xiamen university, xiamen, 361005)

Introduction There has been a very significarnt resurgence of interest in ab initio valence bond calculations recently. This is because the VB calculation based on nonorthogonal basis can provide intuitive understanding about many very important phenomena in chemistry. However, practical calculation based on nonorthogonal basis is still a great challenge even to deal with a quite small system due to the well-known N! (or

关键词： Valence bond theory N-factorial problem Group theory

A SNIFTIRS STUDY OF THE BENZOQUINONE-BENZOHYDROQUINONE REDOX SYSTEM IN AQUEOUS SOLUTION

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Chinese Chemical Letters 1991年第1期2卷 55-56页

作者： Jinkua YOU Huihuang wu department of Chemistry,xiamen university xiamen 361005,Fujian

The in-situ FTIR spectroscopic results show that a hemi-ketal in- termediate may be produced in the electroreduction of benzoquinone or electro- oxidation of benzohydroquinone,which provides a valuable insight into th... 详细信息

关键词： A SNIFTIRS STUDY OF THE BENZOQUINONE-BENZOHYDROQUINONE REDOX SYSTEM IN AQUEOUS SOLUTION FTIR