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掺杂铌对钛酸锶双晶界面势垒的抑制作用

金属功能材料 2002年第1期9卷 29-32页

作者：王岩国张泽中国科学院物理研究所北京电子显微镜实验室北京2724信箱100080

用电子全息技术测量了掺铌∑ 13.0 0 1]钛酸锶倾转双晶界面的电势场分布。结果显示掺杂前界面处的Schottky势垒已消失。表明铌原子占据了界面处氧离子空位 ,消除了电荷聚集在界面处的分布状态。有选择性地掺杂金属元素可以补偿晶界面固... 详细信息

用电子全息技术测量了掺铌∑ 13.0 0 1]钛酸锶倾转双晶界面的电势场分布。结果显示掺杂前界面处的Schottky势垒已消失。表明铌原子占据了界面处氧离子空位 ,消除了电荷聚集在界面处的分布状态。有选择性地掺杂金属元素可以补偿晶界面固有的内禀缺陷。

关键词：界面电子全息势场钛酸锶掺杂铌导电陶瓷铁电材料

High Density Multiplication of Graphoepitaxy Directed Block Copolymer Assembly on Rectangle Lattice Template

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High Density Multiplication of Graphoepitaxy Directed Block ...

Recent progresses on the new condensed forms of single-walled carbon nanotubes and energy-harvesting devices

中国化学会第2.届学术年会

作者： Yu-qiang Ma National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 2.0093. china & center for Soft {2. matter physics and Interdisciplinary Research, Soochow University, Suzhou 2.5006, china

＜正＞Generating high density-multiplied nanopatterns through the directed self-assembly of block copolymers （BCPs） will significantly influence the current microelectronics and storage industries

关键词： Block Copolymer High Density Multiplication of Graphoepitaxy Self Assembly

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Science Bulletin 2012年第Z1期 181-186页

作者： CHEN MinJiang1,2.YU Fang1,HU LiJun1 & SUN LianFeng1* 1 National center for Nanoscience and Technology,Beijing 100190,china 2.Graduate School of {2. Academy of sciences,Beijing 100049,china

We demonstrate an effective method to prepare a new condensed form of single-walled carbon nanotubes(crystal of SWNTs) using a series of diamond wire drawing dies.X-ray diffraction indicates that the SWNTs form a two-dimensional triangular lattice with a lattice constant of 19.62.?.An intertube spacing of 3.3. ? of between adjacent SWNTs results in a sharp(002. reflection in the X-ray diffraction ***,we developed an approach based on the Coulomb explosion to separate SWNTs from their *** separated SWNTs have a typical length of several microns and form a nanotree at one end of the original *** separation is convenient and involves no *** studying devices comprising SWNTs,we find that a four-probe technique can be employed to study the filling of and flow within the inner channel of an individual ***/voltage can drive water molecules to have directional flow along an SWNT,and the flowing of water inside an SWNT can induce a voltage gradient force(an induced electromotive force) along the *** energy conversion is realized by the mutual coupling of water dipoles and charge carriers present in *** results suggest that SWNTs can be exploited as molecular channels for water and may find potential application in nanoscale energy ***,a surface-energy generator comprising SWNTs was demonstrated to harvest the surface energy of *** performance(the induction rate for Voc,the value of Voc and the output power) can be significantly enhanced by the Marangoni effect.

关键词： single-walled carbon nanotube(SWNT) crystal of SWNT SWNT tree energy conversion surface-energy generator

Characterization of the sequence distribution of poly （ethylene-co-vinyl acetate）with NMR spectroscopy

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Characterization of the sequence distribution of poly （ethy...

Composition of substituents on pyrrole ring of high-carbon-number geoporphyrins and its dealkylation

第四届全国高聚物分子表征学术讨论会

作者： Zhiqiang Su, Ying Zhao, Xiuqin Zhang, Shannong Zhu, Dujin Wang, Duanfu Xu State Key Laboratory of Polymer physics and Chemistry, Joint Laboratory of Polymer Science and Materials, center for Molecular Science, {2. of Chemistry, {3. Academy of sciences, Beijing 100080, china

＜正＞ High-resolution NMR,either solution or solid-state spectra,can provideabundant structure information and has been paid more attention inrecent years, capable of elucidating not only the details of thechemical structure of a polymer,but also its dynamic *** help of high-resolution NMR techniques, the sequence distributionand condensed state of EVA copolymers can be clearly characterized,helping to further understand the structure-property correlations ofthe corresponding materials on a molecular level.

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chinese Science Bulletin 1999年第3期44卷 267-269页

作者： ZHANG Chunming and LIN Renzi Geochemistry Research center, Jianghan Petroleum institute, Jingzhou 43.102.{2. Department of Geoscience, University of Petroleum , Beijing 100083.{2. Geochemistry Research center Jianghan Petroleum Institute Jingzhou China Department of Geoscience University of Petroleum Beijing China

Geoporphyrins, isolated from source rock, were analyzed on electron ionization mass spectrometry （EIMS） and Tandem mass spectrometry （MS/MS）. The spectrum of ElMS shows that the geoporphyrins are mainly composed of two types: DPEP and eito. Most of the porphyrin carbon numbers are greater than C3.0}/sub>. The daughter spectra of the molecular ions (C3.-3.DPEPs) display the loss of methyl and ethyl groups, which indicate there are ethyl and propyl groups in the mother ions. The average condensed structural formulae, derived from the data of the spectra on MS/MS, have clearly shown the composition of the substituents on the porphyrin pyrrole ring, and the regular changes of the substituents reveal the characteristics of the dealkylation of the porphyrins in the geosphere.

关键词： Tandem mass spectrometry geoporphyrins condensed structural formula dealkylation.

Difference of Crystallization Processes Induced from the Mechanical Milling and Annealing under Normal and High Pressure in Amorphous Fe-N Alloy

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Difference of Crystallization Processes Induced from the Mec...

衬底对化学气相沉积法制备氧化硅纳米线的影响

18th International Conference on High Pressure Science and Technology

作者： Li Liu Bin Yao Shu-E Liu.Xu-Dong Zhao.Wen-Hui Su Department of physics Jilin University Changckun 13.02. P. R. china Department of Material Science Faculty of Science National University of Singapore Singapore 1192.0.{2. for condensed matter and Radiation physics china {2. of Advanced Science and Technology (World Lab) PO Box 873. Beijing 100080 P. R. china

＜正＞ Based on crystallization thermodynamics and kinetics, crystallization products of amorphous alloys are mainly influenced by pressure, temperature and composition, and the crystallization temperature is affected by pressure and composition. However, only the effects of temperature and composition on mechanical crystallization were considered in previously reported works. In order to confirm the effect of high local pressure on crystallization of amorphous Fe-N alloy, an amorphous Fe-N alloy was prepared by ball milling of a mixture of Fe and hexagonal boron nitride. Its crystallization processes were studied in the case of mechanical milling （MM） and annealing under normal and high pressure. The 2.h-milled sample containing amorphous Fe-N was annealed for In under pressures of 2.to 4GPa and at temperatures ranging from 580K to 1170K.. XRD showed the result of the difference between MM process and thermal crystallization process. It crystallizes to e-FexN containing N content much less than its lower composition limit of 2.at% under normal pressure during MM and annealing under high pressure, while it transforms into γ-Fe4N during annealing under normal pressure. It was demonstrated in the present experiment that the ε-FexN with lower N content is a thermodynamic stable state under pressures of 3.to 4 GPa and at temperatures from 690K to 800K, though it is not under normal pressure. Therefore, the difference in crystallization product between mechanical and thermal crystallization is attributed to the effects of local pressure and local temperature on thermodynamic stable state of Fe-N alloy.

关键词： Fe-N alloy Crystallization High pressure.

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物理学报 2003年第2期52卷 454-458页

作者：闫小琴刘祖琴唐东升慈立杰刘东方周振平梁迎新袁华军周维亚王刚中国科学院物理研究所中国科学院凝聚态物理中心北京100080

通过化学气相沉积法在不同衬底上制备了大量的氧化硅纳米线 .选用衬底为Si片、带有约 10 0nm厚SiO2.氧化层Si片和石英片 .利用场发射扫描电子显微镜 (SEM)和透射电镜 (TEM ,配备有能谱仪 )对样品的表面形貌、结构和成分进行研究 .结果表... 详细信息

通过化学气相沉积法在不同衬底上制备了大量的氧化硅纳米线 .选用衬底为Si片、带有约 10 0nm厚SiO2.氧化层Si片和石英片 .利用场发射扫描电子显微镜 (SEM)和透射电镜 (TEM ,配备有能谱仪 )对样品的表面形貌、结构和成分进行研究 .结果表明 :这些纳米线都为非晶态 ,但在不同衬底上生长的纳米线形貌、尺寸和化学成分不同 .讨论了各种衬底对不同特征氧化硅纳米线生长的影响 .

关键词：衬底氧化硅化学气相沉积纳米线纳米颗粒纳米材料

The Production and Release of CFCs from Coal Combustion

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 81-85页

作者： LI Jiaxi, WANG Junzhi, LI Hong, RAO Zhu, LI Qi and LUO Songguang National Research center of Geoanalysis, chinese Academy of Geological {2., Beijing 10003. chinese Acad Geol Sci Natl Res Ctr Geoanal Beijing 100037 Peoples R China

The destruction of the ozone layer in the atmosphere caused by industriallysynthesized CFCs has aroused greatest concerns from the international society, but the CFCs formedfrom burning of coal containing fluorine have not been recognized by the world yet. In the presentstudy, we condensed the gas through cold traps and used the GC-MS to measure the gas composition,and found that the content of CFC-12.in the smog from coal combustion was significantly higher thanthe background value of the local atmosphere. This proves that CFC- 12.is formed in the process ofcoal combustion. This paper discusses a new source of non-synthesized CFCs.

关键词： CFC-12.in coal combustion measurement of CFC-12 halo hydrocarbons fromcoal

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氧化物超导体的高压热处理及烧结

高压物理学报 1988年第2期2卷 159-164页

作者：黄新明崔长庚陈红徐小平何寿安王文魁中国科学院物理研究所凝聚态和辐射物理分中心中国高等科学技术中心

本文利用高温高压条件,对氧化物超导体进行了不同条件的高压热处理及烧结。发现对SrLa（CuAg）1Ox在空气中烧结的超导体,适当条件的高压热处理,使Tc从2.K提高到2.K。在Y1Ba2.u3.7-d系氧化物中,无论是对空气中烧结的已超导样品的高压热处... 详细信息

本文利用高温高压条件,对氧化物超导体进行了不同条件的高压热处理及烧结。发现对SrLa（CuAg）1Ox在空气中烧结的超导体,适当条件的高压热处理,使Tc从2.K提高到2.K。在Y1Ba2.u3.7-d系氧化物中,无论是对空气中烧结的已超导样品的高压热处理,或者直接在高压下烧结样品,均未使Tc得到提高,但是,经过高压烧结,超导样品的硬度显著提高,密度也有所增加,并且改变了超导相的晶格常数。

关键词：氧化物超导体高压烧结临界温度晶格常数