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排序方式: 共有1323条查询结果,搜索用时 46 毫秒
101.
102.
Barium titanium trioxide (BaTiO3) thin films were deposited on fused silica or silicon wafer substrate from barium dipivaloylmethanate (II) (Ba(dpm)2) and titanium tetraisopropoxide (IV) (TTIP) used as precursors in an oxygen microwave plasma. The substrates were dielectrically heated and the substrate temperatures were around 900 K during the film deposition. The deposition was performed for 15 min and the deposits were identified as BaTiO3 by means of X-ray diffraction, X-ray photoelectron spectroscopy, infrared spectroscopy, and ellipsometry. Oxygen and barium atoms and TiO and CO molecules were identified in the plasma. These species would produce higher deposition rates at lower substrate temperatures than those did in the usual thermal metalorganic chemical vapor deposition (MOCVD). The dielectric constant of the BaTiO3 thin film that was directly deposited on the silicon wafer substrate was as low as 101 order of magnitude. Because the deposit reacted with the substrate and an interdiffusional layer was formed, the platinum layer was coated on the silicon wafer substrate in order to prevent the formation of an interdiffusional layer. The dielectric constant then increased to 103 order of magnitude. 相似文献
103.
Osamu Kitao Ersan Demiralp Tahir Cagin Siddharth Dasgupta Masuhiro Mikami Kazutoshi Tanabe William A. Goddard III 《Computational Materials Science》1999,14(1-4):135-137
Aluminophosphate zeolite is an artificial material which shows strange hydrophilicity. We have been investigating the reason by quantum mechanics, and found that the hydrophilicity of this zeolite depended on the local geometric deformation, and speculated that the site-specific hydrophilicity might be explained by differences in the stiffness of the local deformation determined by the location with the pore structure. In order to test these ideas, we construct a reliable force field based on the new MS-Q approach developed by Demiralp, Cagin, and Goddard. Our force field well reproduces the experimental structure of VPI-5. 相似文献
104.
The characteristics of pattern replication and releasing in a roll-to-roll ultraviolet- (UV) curing embossing process were investigated. The roll embossing system was designed for large-area continuous embossing, with employment of a fast curing resin, a heat damage protector, and a surface energy reducing coating. A 60° V-groove pattern with a groove period of 30 µm was embossed. It was found that the replication quality was profoundly influenced by the pattern geometry, the pattern direction, and the mold surface energy. In particular, the pattern direction significantly affected the edge sharpness and the surface topography of replicated features. In the parallel groove mode, a significant amount of tearing and sliding occurred, whereas in the transverse groove mode, biting marks were observed on the side wall of the V-groove. A simple mechanical model was used to explain the difference in pattern releasing with different pattern layouts. The replication quality was found to be significantly improved with the application of a fluorinated coating on the roll mold. 相似文献
105.
The synergistic effect of methyltrioctylammonium chloride (QCI) on the extraction of Np(V) by 1-phenyl-3-methyl-4-benzoyl-pyrazolone(HP) in benzene is studied over the pH range 2-6. This system extracts Np(V) better than any previously reported. The interaction of the extractants and monomer-dimer equilibria affect the distribution behavior of Np(V) in a complicated manner. Analysis of the results suggests that NpO2 + (M+) is extracted as mixed dimers, (QMP2QCl)o and (QMP2QP)o. 相似文献
106.
Asaji Sato Osamu Sato Nobuya Takahashi Masahiro Yokomichi 《Artificial Life and Robotics》2011,16(2):169-173
In this article, equations of motion of a manipulator are derived after consideration of the characteristics of the driving
source. By considering a collision between a link and an object, and considering the active motion to absorb the kinetic energy
of the object, the trajectories for saving energy are calculated by the iterative dynamic programming (IDP) method. The dynamic
characteristics of manipulator control based on the trajectory for saving energy are also analyzed theoretically and investigated
experimentally. 相似文献
107.
Summary
Copolystyrenes complexed with macrocyclic compounds through hydrogen bonding have been synthesized by the copolymerization
of styrene with the complex of 4-vinylbenzoic acid and crown ethers containing a 2,6-pyridyl moiety. The glass transition
temperatures of the copolymeric complexes are significantly lower than that of the simple copolymer, which shows that the
carboxylic acid groups in the polymer backbone do not intermolecularly dimerize. The UV absorption spectra of polymeric complexes
suggest that they have complex structures similar to that of the low-molecular-weight complexes of 4-ethylbenzoic acid and
the crown ethers.
Received: 31 March 1999/Accepted: 27 April 1999 相似文献
108.
The paper describes required technological innovation for voltage control of power systems under deregulation of power supply industries and presents a new concept of an autonomous control system for the voltage and reactive power of power systems. Installation of distributed generation connected to distribution networks will significantly increase the short circuit capacity of distribution lines. Therefore, GIS underground substations in the center of a large city are required to enable replacement of circuit breakers with ones of greater capability and to reform GIS bus configurations. Furthermore, a more detailed forecast of local demand and operation data of distributed generators are required for the stable control of voltage and reactive power. This paper presents methods of on‐line autonomous forecasting for short circuit capacity and demand of local transmission and distribution lines, which are indispensable for voltage and reactive control under deregulation of electric power supply industries. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 27–37, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20450 相似文献
109.
110.
Osamu Hirota 《Applicable Algebra in Engineering, Communication and Computing》2000,10(4-5):401-423
This paper presents a review and some results on problems of super additiveness in quantum channel for Shannon information.
Especially, how to investigate concrete systems showing super additiveness is discussed. It is verified that the concept of
the conventional error correction scheme does not play an important role to demonstrate, at least, the super additiveness
of quantum channel, and that rather one can apply them to only selection of code word states with desirable Hamming distance.
Finally, some properties of quantum reliability function are given, which are useful to discuss the general property of coding
with super additiveness.
Received: September 29, 1998; revised version: July 9, 1999 相似文献