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91.
During the course of studies on butenolide synthesis1 we have investigated the utilities of 3-sulfur-functionalized propionic acid derivatives. We report the results with 3-carbanion species obtained from 3-phenylsulfiny1- and 3-phenylsulfonylpropionic acids (1) and (2). These compounds were easily prepared from 3-phenylthiopropionic acid. 相似文献
92.
We present tamper resistance in optical excitation transfer via optical near-field interactions based on the energy dissipation process occurring locally in nanometric devices such as quantum dots. A theoretical comparison with electrical systems is also shown, focusing on the required environmental conditions. Numerical simulations based on virtual photon models demonstrate high tamper resistance. 相似文献
93.
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95.
Hisami Yumoto Shigekazu Onozumi Yoshinori Kato Masatou Ishihara Kiyoshi Kishi 《Crystal Research and Technology》1996,31(2):159-164
Indium tin oxide (ITO) whiskers were grown by VLS (vapour-liquid-solid) mechanism, using the electron shower method. The whiskers were grown above 200 °C, and the deposition rate was above 0.6 nm/s. The electron shower controlled the size of the whiskers, and the size was 30 nm in diameter and 600 nm in length. The whiskers grew along the substrate at t < 300 s, but grew in a direction perpendicular to the substrate at t > 300 s. When the ITO whiskers grown along the substrate were used as NO2 gas sensor, the sensitivity was 340, and about 300 times higher than those of the whiskers grown in a direction perpendicular to the substrate and plate-like ITO crystallites. 相似文献
96.
Boris M. Epelbaum Kiyoshi Shimamura Satoshi Uda Junichi Kon Tsuguo Fukuda 《Crystal Research and Technology》1996,31(8):1077-1084
The μ-PD method originally developed for oxide crystals has been modified and applied for filamentary silicon crystal growth. Our main modification of μ-PD method is concerned with an arrangement of melt permeable feeder which is inserted into the nozzle. The feeder finishes by a sharp tip the diameter of which (is almost the same as that of the desired semiconductor fiber, i.e., less than 150 μm. Silicon fibers were grown from the small liquid pool at the end of the feeder. Three types of crucible-die arrangement were designed and tested. The best results were obtained with the help of inclined insert made of graphite fibers because of its ability to quench oscillations and longer operation life. Fiber crystals, 100 μm in diameter and 70 mm in length, have been grown successfully. Small meniscus stability, operating limits of μ-PD method and silicon carbide formation during the growth process are discussed. 相似文献
97.
Alcoholysis, hydrolysis, and acetolysis of epoxides were carried out in the presence of a catalytic amount of aniline-terephthalaldehyde resin p-toluenesulfonate (ATRT) to give the corresponding β-substituted alcohols in good yields. Alcoholysis and hydrolysis of epoxides catalyzed by ATRT proceeded faster than those by pyridinium p-toluenesulfonate (PPTS). 相似文献
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99.
We discuss a rigid string model proposed by Casalbuoni and Longhi. Constraints for the massive states are solved to find the physical states and the mass spectrum. We also find its supersymmetric extension with the kappa symmetry. The supersymmetry transformations are found starting from on-shell transformations using the Dirac bracket. 相似文献
100.
We study reflection diffuse optical tomography using two-dimensional (2D) continuous-wave source-detector arrays on the surface
of semi-infinite medium, aiming at imaging the perfusion and the hemoglobin oxygen saturation variation of human cerebral
cortex with brain activation. We had previously formulated the inverse problem with Moore-Penrose inversion. When we use simple
regularization in this inverse problem, the reconstruction sensitivity decreases markedly with the depth so that the signal
in the deep range may be masked by an unwanted signal in the shallow range. In this paper, we propose a depth-adaptive regularized
reconstruction, in which we assign a smaller regularization parameter with the depth. We demonstrate improvement of the three-dimensional
(3D) reconstruction uniformity using the proposed scheme. 相似文献