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排序方式: 共有7943条查询结果,搜索用时 12 毫秒
941.
Inorganic nanotubes have been a subject of intensive research in the past decade. We recently developed a number of synthetic strategies for generating nanotubes from inorganic materials that do not have a layered structure. It is the intention of this contribution to provide a brief account of these research activities. 相似文献
942.
U. Bogner R. Seel F. Graf C. R. Pollock D. A. Jennings F. R. Petersen R. E. Drullinger E. C. Beaty J. S. Wells J. L. Hall H. P. Layer K. M. Evenson Ch. Salomon Ch. Bréant A. van Lerberghe G. Camy Ch. J. Bordé K. J. Siemsen H. D. Riccius A. S. Südbø Guiguang Xiong 《Applied physics. B, Lasers and optics》1982,29(3):152-156
943.
A recent global optimization algorithm using decomposition (GOP), due to Floudas and Visweswaran, when specialized to the case of polynomial functions is shown to be equivalent to an interval arithmetic global optimization algorithm which applies natural extension to the cord-slope form of Taylor's expansion. Several more efficient variants using other forms of interval arithmetic are explored. Extensions to rational functions are presented. Comparative computational experiences are reported. 相似文献
944.
S.B. Xiong Z.M. Ye X.Y. Chen X.L. Guo S.N. Zhu Z.G. Liu C.Y. Lin Y.S. Jin 《Applied Physics A: Materials Science & Processing》1998,67(3):313-316
x Ba1-xNb2O6 (x=0.5) films (abbreviated as SBN:0.5) on SiO2-coated Si substrates are potential components for the application of integrated electro-optics devices. SBN:0.5 optical waveguiding
thin films on SiO2-coated Si substrates with a very thin MgO diffusion buffer have been successfully prepared by pulsed laser deposition. The
as-grown films have a refractive index of 2.28, which is close to that of bulk SBN. X-ray analysis showed that the as-grown
films have a single-phase tetragonal tungsten bronze structure. The SBN:0.5 thin films prepared by PLD exhibit favorable ferroelectric
and optical waveguiding properties. The composition and the morphology of the films were also examined by XPS and by SEM,
respectively. Ferroelectric SBN:0.5 optical waveguiding thin films on SiO2-coated Si substrates are expected to be used in integrated electro-optic devices.
Received: 27 February 1997/Accepted: 17 October 1997 相似文献
945.
T. Yu Y.-F. Chen Z.-G. Liu L. Sun S.-B. Xiong N.-B. Ming Z.-M. Ji J. Zhou 《Applied Physics A: Materials Science & Processing》1996,64(1):69-72
The semiconductive perovskite-type oxide SrFeO3-x (x<0.16) (SFO) thin films have been directly fabricated on (001)SrTiO3 and (001)LaAlO3 single crystal substrates by pulsed laser deposition(PLD) under high oxygen partial pressure of 100 Pa. The SFO thin films
were (110) oriented. The x-ray photoelectron spectroscopy (XPS) analysis showed that the surface of SFO thin film has strong
gas absorption capability. The resistance versus temperature has been measured in the temperature range from 77 K to 300 K.
The SFO thin film showed typical semiconductive property. Dependence of resistance of SFO thin film on oxygen pressure was
measured and result showed that the SFO thin film had better oxygen sensitive property.
Received: 14 May 1996/Accepted: 15 August 1996 相似文献
946.
947.
大孔膦酸树脂吸附钴的性能及其机理 总被引:11,自引:1,他引:10
大孔膦酸树脂吸附钴的性能及其机理熊春华,莫建军(丽水师专化学系,丽水323000)林峰(杭州大学化学系,杭州310028)关键词胰酸树脂,钴,吸附大孔磷酸树脂的合成、结构、某些性能和应用已有报道[1,2],但是在HAc-NaAc体系中吸附金属钻(Ⅱ)... 相似文献
948.
Ji-Ben Meng Da-Ming Du Guo-Xiang Xiong Wen-Guang Wang Yong-Mei Wang Hideko Koshima Teruo Matsuura 《Journal of heterocyclic chemistry》1994,31(1):121-124
The solid-state photoreaction of the mixed crystals between nitrobenzaldehydes and indole was found to give nitrophenyl-(bis-3-indolyl)methane ( 3 ) and nitrophenyl-(3-indolyl)methanol ( 4 ). The structure of the ortho isomer 4c was established by X-ray crystallographic analysis. A dual pathway from an oxetane intermediate 5 is proposed for the formation of 3 and 4 . 相似文献
949.
950.
采用磁控溅射法,以镍硅合金为靶,制备了一种适用于金属诱导横向晶化的氧化物镍源——自缓释镍源.该镍源在内部构成和晶化现象上都不同于纯金属镍源.采用该镍源制备低温多晶硅材料,晶化速率不明显依赖于镍源薄膜的厚度,且晶化多晶硅膜内的残余镍量亦可有效降低,可为薄膜晶体管提供宽的工艺窗口.本文对用纯金属镍源所得多晶硅薄膜的晶化率、表面粗糙度、电学特性等与溅射条件的关系进行了研究,并对相应结果进行了讨论.
关键词:
自缓释
金属诱导横向晶化
多晶硅薄膜
低温制备与退火 相似文献