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Nano Research 2009年第8期2卷 630-637页

作者： Yaling Liu Zhuoyu Ji Hongxiang Li Wenping Hu Yunqi Liu Daoben Zhu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China National Center for Nanoscience and Technology Beijing 100190China Department of Compound Semiconductor Devices and Circuit Institute of MicroelectronicsChinese Academy of SciencesBeijing 100029China

Two simple methods have been demonstrated to obtain large area,single crystalline lamellae of copper-7,7,8,8-tetracyanoquinodimethane(CuTCNQ).The formation of the lamellae was a result of fine tuning of the processes during the synthesis processes of CuTCNQ phase *** facile synthesis of large area single crystalline lamellae suggests bright prospects for the study and understanding of the electrical switching of CuTCNQ by using single crystals of its phase II,and future applications of the material in memory and switching devices.

关键词： CuTCNQ lamellae single crystals phase II

Folded-chain lamellae interphase in flexible polymers

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Chinese Science Bulletin 1996年第16期41卷 1347-1352页

作者：朱清仁庞文民张裕恒黄元华 Structure Research Laboratory University of Science & Technology of China Hefei 230026 China Department of Applied Physics The Hong Kong Polytechnic University Hong Kong

In a semicrystalline aggregate of flexible chain polymers, a large amount of the adjacent regularly-folded tiny lamellae coexists with the amorphous phase whose chains have only random spatial arrangement. This ’crystalline-noncrystalline’ two-phase model has been widely accepted and used to describe the structure and properties of polymers in condensed state. The crystalline morphology of PE prepared by various methods have

关键词： crystalline PE phase structure interphase 13C NMR folded-chain lamellae

Peptide self-assembly into lamellar phases and the formation of lipid-peptide nanostructures

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Nano Research 2018年第2期11卷 913-928页

作者： Karin Kornmueller Bernhard Lehofer Gerd Leitinger Heinz Amenitsch Ruth Prassl Institute of Biophysics Medical University of Graz BioTechMed-Graz Graz Austria Institute of Cell Biology Histology and Embryology Research Unit Electron Microscopic Techniques Medical University of Graz Graz Austria Institute of Inorganic Chemistry Graz University of Technology Graz Austria

Lipids exhibit an extraordinary polymorphism in self-assembled mesophases, with lamellar phases as the most relevant biological representative. To mimic lipid lamellar phases with amphiphilic designer peptides, seven systematically varied short peptides were engineered. Indeed, four peptide candidates （V4D, V4WD, V4WD2, I4WD2） readily self-assembled into lamellae in aqueous solution. Small-angle X-ray scattering （SAXS） patterns revealed ordered lamellar structures with a repeat distance of 4-5 nm. Transmission electron microscopy （TEM） images confirmed the presence of stacked sheets. Two derivatives （V3D and V4D2） remained as loose aggregates dispersed in solution; one peptide （L4WD2） formed twisted tapes with internal lameUae and an antiparaUel -type monomer aligrtment. To understand the interaction of peptides with lipids, they were mixed with phosphatidylcholines. Low peptide concentrations （1.1 mM） induced the formation of a heterogeneous mixture of vesicular structures. Large multilamellar vesicles （MLV, d-spacing - 6.3 nm） coexisted with oligo- or unilamellar vesicles （- 50 nm in diameter） and bicelle-like structures （- 45 nm length, - 18 nm width）. High peptide concentrations （11 mM） led to unilamellar vesicles （ULV, diameter - 260-280 nm） with a homogeneous mixing of lipids and peptides. SAXS revealed the temperature-dependent fine structure of these ULVs. At 25 ℃ the bilayer is in a fully Interdigitated state （headgroup-to-headgroup distance dH, -2.9 nm）, whereas at 50 ℃this interdigitation opens up （dtm- 3.6 nm）. Our results highlight the versatility of self-assembled peptide superstructures. Subtle changes in the amino acid composition are key design elements in creating peptide- or lipid- peptide nanostructures with richness in morphology similar to that of naturally occurrin~ lioids.

关键词： amphiphilic designerpeptides lipids nanostructures lamellae small-angle X-rayscattering (SAXS) transmission electronmicroscopy (TEM)

DEFORMATION　AND　FRACTURE　MECHANISMS　OF　TWO－PHASE　TiAl－BASED　ALLOYS　WITH　FULLY　LAMELLAR　MICROSTRUCTURE

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 359-368页

作者： Y. G .Zhang, C. Q. Chen (Beijing University of Aeronautics and Astronautics, Beijing 100083, China)Q. Xu (Beijing Laboratory of Electron Microscopy, Chinese Academy of Sciences. Beijing,China)M. C. Chaturvedi (The University of Manitoba, Winnipeg, Manito Beijing Univ of Aeronautics and Astronautics Beijing China

A two-phase TiAl-based alloy with fully lamellar structure has been deformed al room temperature and the deformed microstructures have been examined in dtails by optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM) . Deformation mechanisms in the γ-TiAl phase has been defined and the role of grain boundaries in the deformation and fracture has been assessed Some of the mechanisms of interactions between twinning or gliding dislocations and three types of γ γ domain boundaries or γ α_2 interface in a lamellar grain have been identified and resistance of the various domain boundaries or the interface to the propagation of twinning has been evaluated

关键词： TiAl Deformation mechanism lamellae Twinning

THE CRYSTALLIZATION BEHAVIOR OF URETHANE SUBSTITUTED POLYDIACETYLENE

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Chinese Journal of Polymer Science 1989年第2期7卷 174-178页

作者：陈寿羲 G. Wegner Institute of Chemistry Academia SinicaBeijingChina Max-Planck-Institute of Polymer Jakob-Welder-Weg 15D-6500 MainzWest Germany

The crystalline behavior of urethane substitute polydiacetylene was studied by using pohrized light and electron microscopy. The lamellar morphological structure was observed in the crystallized films. The thickness of lamellae is about 300A, being independent of the crystalline temperature. But the size and density of lamellae were dependent on the crystallization temperature. If the molten film was sheared during the crystallzation process the oriented lamellae grew with their long axes perpendicular to the direction of shear and the chain direction was normal to the lamellar surface.

关键词： Crystallization behaviour lamellae Electron microscopy Urethane substituted polydiacetylene.

In-situ crack propagation observation in fully lamellar Ti-49%Al alloy

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中国有色金属学会会刊：英文版 2000年第5期10卷 599-602页

作者：陆永浩张永刚乔利杰王燕斌陈昌麒褚武扬 Beijing Univ Sci & Technol Dept Phys Mat Beijing 100083 Peoples R China Beijing Univ Aeronaut & Astronaut Dept Mat Sci & Engn Beijing 100083 Peoples R China

The fracture mechanism of lamellar Ti 49%Al alloy was investigated through studying the interactions between crack and lamellae or grain boundary. The results indicated that the nucleation and propagation mechanisms of crack depends on not only the lamellar orientations within grain but also the types of grain boundaries. When the angle between tensile axis and lamellae is relatively large, the main crack parallel to the lamellae propagates by nucleation, growth and linkage with interfacial microcracks. When the tensile axis is nearly parallel to the lamellae, the main crack perpendicular to the lamellae propagates by nucleation, growth and linkage with two types of microcracks, e.g. translamellar microcrack and interface delamination. In addition, the interlock grain boundary nearly parallel to the tensile axis is benefit to fracture toughness, the grain boundary nearly perpendicular to the tensile axis is bad for the toughness. [

关键词： TiAl alloy lamellae crack grain boundary fracture mechanism

ROD-LIKE AGGREGATES FROM POLYSTYRENE-b-POLY(4-VINYLPYRIDINE)-b-POLYSTYRENE TRIBLOCK COPOLYMER IN AQUEOUS MEDIA

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Chinese Journal of Polymer Science 2004年第1期22卷 17-23页

作者：程时远江雷 College of Chemistry & Materials Sciences Hubei University Wuhan 430062 China Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The rod-like assembly from BAB block copolymer with hydrophilic middle block A in aqueous solution was described. The copolymer used is polystyrene (PS)39-b-poly(4-vinylpyridine)(P4VP)98-b-PS39 (the subscripts are the average polymerization degree of corresponding blocks) triblock copolymer with Mw/Mn = 1.15. The aggregates were characterized by transmission electron microscopy and atomic force microscopy. The dependence of rod-like aggregate formation on solvents, pH, and polymer concentrations was investigated. The rod-like aggregates were formed when using dioxane as initial solvent, while spherical micelles were formed using DMF. Elevating pH values from 4 to 5 to 7 and decreasing initial copolymer concentrations from 1.5 wt% to 1.0 wt% to 0.5 wt% were favorable for the formation of well-defined rod-like aggregates. In addition, the bicontinuous rods and lamellae were observed when preparing colloid solutions in appropriate conditions.

关键词： Block copolymers Self-assembly Rod-like aggregates Bicontinuous lamellae

TRANSMISSION ELECTRON MICROSCOPY OF SEGMENTED POLYURETHANES WITH RUTHENIUM TETROXIDE AS A STAINING AGENT

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Chinese Journal of Polymer Science 1991年第3期9卷 246-250页

作者：肖凤飞陈寿羲金永泽施良和徐懋 Polymer Physics Laboratory Institute of Chemistry Academia Sinica Beijing 100080

Microphase separation and lamellar structure of segmented polyether- and polyester-polyurethanes have been investigated by means of transmission electron microscopy with the ruthenium tetroxide staining technique. The results show that the RuO_4 staining technique is simpler and may give better image contrast than other staining methods for this polymer. Microphase separation and lamellar structure of segmented polyether-and polyester-polyurethanes were directly observed and discussed.

关键词： Microdomain structure lamellae Ruthenium tetroxide stain Segmented polyurethane.

Effects of Agrobacterial<i>rol</i>-Genes on the Thermodynamic and Structural Features of Starches Extracted from Potato Microtubers

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Food and Nutrition Sciences 2014年第3期5卷 250-257页

作者： Luybov A. Wasserman Nina P. Aksenova Tatiyana N. Konstantinova Lidiya I. Sergeeva Svetlana A. Golyanovskaya Alexey V. Krivandin Georgy A. Romanov Emmanuel Institute of Biochemical Physics Russian Academy of Sciences Moscow Russia imiryazev Institute of Plant Physi- ology Russian Academy of Sciences Moscow Russia Timiryazev Institute of Plant Physi- ology Russian Academy of Sciences Moscow Russia Timiryazev Institute of Plant Physi- ology Russian Academy of Sciences Moscow Russia Laboratory of Plant Physiology Wageningen University Wageningen The Netherlands.

Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorimetry (DSC). It was found that in starch from tubers of rolB plants the melting temperature of crystalline lamella was lower and their thickness was less than that in wild-type potato. In tubers of rolC plants starch differed from starch in wild-type plants by a higher melting temperature, reduced melting enthalpy, and a greater thickness of crystalline lamellae. The melting of starch from tubers of rolC plants proceeded as the melting of two independent crystalline structures with melting temperatures of 338.0°K and 342.8°K. Overall data show that starches of different structure can be obtained by using transgenic approach.

关键词： Solanum tuberosum Transgenic Potato Starch rol Genes Tubers Crystalline lamellae Melting Temperature

Discovery of Shock Metamorphic Quartz at Taihu Lake Zeshan Island and Its Implications

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Chinese Science Bulletin 1994年第5期39卷 419-423页

作者：王尔康万玉秋施央申 V.L.Sharpton K.Burke Department of Earth Sciences Nanjing University Nanjing 210008 PRC Lunar and planetary Institute HoustonTexas 77058USA Department of Geosciences University of HoustonHoustonTexas 77204USA

The origin of Taihu Lake has attracted the attention of several generations ofChinese geologists. Especially the impact origin hypothesis was put forward by *** Zhi-zhong. In the beginning of the 1990s, based on the previous hypotheses, differ-ent views have been advanced one by one. These indicate that research work aboutthe Taihu Lake origin is in a deep-going way.

关键词： shock’metamorphism quartz shock lamellae origin of Taihu Lake.