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961.
962.
We examine fast particle energy loss as a probe of the properties of a density modulated 2DEG in a normal magnetic field. In the high velocity limit, the local plasmon spectrum makes two separate contributions to energy loss for both the cases in which the particle velocity is parallel and perpendicular to the planar 2DEG. The inter-Landau band plasmon makes a distinct contribution to energy loss through excitation of the hybrid 2D magnetoplasmon. The other local plasmon, associated with the spread of a Landau level into a miniband by application of the periodic potential associated with the density modulation contributes to energy loss with features corresponding to Shubnikov-de Haas oscillations jointly with an amplitude envelope exhibiting oscillations associated with the commensurability of the modulation period and the cyclotron radius at the Fermi energy. 相似文献
963.
JIANG Shaoen XU Yan DING Yongkun LAI Dongxian ZHENG Zhijian HUANG Yixiang LI Jinghong SUN Kexu HU Xin ZHANG Wenhai YI Rongqing CUI Yanli & CHEN Jiusen . National Key Laboratory of Laser Fusion Laser Fusion Research Center Mianyang China . Institute of Applied Physics Computation Mathematics Beijing China 《中国科学G辑(英文版)》2005,48(5):549-558
1 Introduction The investigation of supersonic radiation wave transporting in low density foam pro-duced by thermal radiation is of crucial importance in inertial confinement fusion (ICF) research[1]. When the intense radiation flux is incident in the media, first, a supersonic heat wave is formed which propagates into the undisturbed material. In time, due to the increasing mass of heated material, it slows down and is overtaken by a shock wave,thus becoming of the ablative type. Normally, … 相似文献
964.
Yunan Cui Henryk Hudzik Hongwei Zhu 《Proceedings of the American Mathematical Society》1998,126(1):115-121
Maluta's coefficient of Musielak-Orlicz sequence spaces equipped with the Orlicz norm is calculated. A sufficient condition for the Schur property of these spaces is given.
965.
966.
967.
单重态氧发生器出口气流中水汽含量的光谱测量法 总被引:1,自引:1,他引:0
水汽的含量是化学法单重态氧发生器(SOG)的重要性能参数之一,因为它不仅对O_2( ̄1△)有猝灭作用,而且在氧碘化学激光器(COIL)光腔中对I ̄*也有严重猝灭作用。因此测控SOG出口处的水汽含量有重要意义。本实验采用光谱强度比较法测量SOG中的水汽含量,利用OMA-3的二维扫描积累功能,可对不同测点的光谱进行同时扫描积累,从而可以对SOG的数个测点同时进行水汽含量测定。测试精度可达±10%。 相似文献
968.
Cui L Xuan Y Li X Ding Y Li B Han Y 《Langmuir : the ACS journal of surfaces and colloids》2005,21(25):11696-11703
Honeycomb macroporous films fabricated by the "breath figures" method were composed of poly2-vinylpyridine (P2VP) distributed in the holes of polystyrene (PS). The porous films exhibited reversible behavior responding to water and different solvent vapors. When the porous film was treated with water, the honeycomb pattern would change to the hexagonal islandlike pattern. Once heated to remove the water, the honeycomb pattern emerged again. When the porous film was exposed to different solvent vapors, the same reversible process appeared. Carbon disulfide (CS(2)), toluene (TOL), and tetrahydrofuran (THF) solvent vapors induced the honeycomb pattern into the ordered islandlike pattern, and ethanol, chloroform, methyl ethyl ketone (MEK), and dimethylformamide (DMF) solvent vapors made the islandlike pattern come back to the honeycomb pattern. The hygroscopic property of P2VP and the polymer-solvent interaction are the driving force for the reversibly switchable morphology. The appropriate control of the hole depth is very crucial in determining the reversible changes. 相似文献
969.
The carbene complex can mediate hydrogenations of dienes with up to 20:1.0 diastereoselectivity and 99% ee; the scope and limitations of these reactions were investigated. 相似文献
970.