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排序方式: 共有1215条查询结果,搜索用时 46 毫秒
41.
Hiroshi Nakatsuji Yoshinari Kamakura Kenji Taniguchi 《Journal of Computational Electronics》2003,2(2-4):109-112
Transport properties of the two-dimensional hole gas in inversion layer of strained Si/SiGe p-MOSFETs are investigated using the full-band Monte Carlo simulator based on the nonlocal pseudopotential calculation. The hole mobility is significantly enhanced by the strain in the case of Ge content of ≥20%. Moreover, we also present the high-field transport characteristics of 2D holes. In contrast to the low-field mobility, the hole saturation velocity does not significantly enhanced by the strain. 相似文献
42.
Atsushi Sakai Yoshinari Kamakura Kenji Taniguchi 《Journal of Computational Electronics》2004,3(3-4):449-452
We report the two- and three-dimensional quantum lattice-gas automata simulation for one-particle electronic wave propagation in nanostructures. The transmission coefficient of the electronic wave through the two-dimensional quantum point contact is investigated taking account of the surface roughness of the confinement wall. It is demonstrated that the electron transmission is significantly affected by the surface roughness pattern even if the same roughness parameter is assumed. We also perform the three-dimensional simulation, and the wave propagation in the structure like an ultrathin-body MOSFET is visualized. 相似文献
43.
Takayoshi Yokoya Rikiya Yoshida Yuki Utsumi Koji Tsubota Hiroyuki Okazaki Takanori Wakita Yoshikazu Mizuguchi Yoshihiko Takano Takayuki Muro Yukako Kato Hiroshi Kumigashira Masaharu Oshima Hisatomo Harima Yoshihiro Aiura Hitoshi Sato Akihiro Ino Hirofumi Namatame Masaki Taniguchi Masaaki Hirai Yuji Muraoka 《Science and Technology of Advanced Materials》2012,13(5)
We have characterized the electronic structure of FeSe1−xTex for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (EF): its splitting near EF and filling of the pseudogap in FeSe. IPES shows two features, near EF and approximately 6 eV above EF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near EF for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe. 相似文献
44.
Nanoporous structure of the cell walls of polycarbonate foams 总被引:1,自引:0,他引:1
Using CO2 to prepare microcellular polycarbonate foams resulted in a pore diameter of 45 nm and a pore density of 108 cm?2 on the walls of microscale cells, which created nano/micro foams with an open cell structure. In this study, the craze nucleation theory and the bubble nucleation theory of foaming were combined to explain the mechanism of the foaming-induced nanopores (microvoids) on the cell walls. In the foaming process, the strain energy was developed in the cell walls by bubble nucleation and growth. With large strain energy, a nanoporous structure of the cell walls was formed by initiation of crazing. Because the foaming temperature affected the strain energy in the cell wall, the temperature became a key factor of forming microcellular structure as well as the nanopores on the cell walls. Our experimental results showed that the diameter and density of the nanopores were determined by the competitive movements between chain stretching and relaxation. Furthermore, certain solvents, such as acetone, were found to increase the nanopore density of the walls by exploiting the plasticization effect of the solvent on the reduction of surface tension and viscosity. 相似文献
45.
E.-A. Reinecke K. Takenaka H. Ono T. Kita M. Taniguchi Y. Nishihata R. Hino H. Tanaka 《International Journal of Hydrogen Energy》2021,46(23):12511-12521
The safe decommissioning as well as decontamination of the radioactive waste resulting from the nuclear accident in Fukushima Daiichi represents a huge task for the next decade. At present, research and development on long-term safe storage containers has become an urgent task with international cooperation in Japan. One challenge is the generation of hydrogen and oxygen in significant amounts by means of radiolysis inside the containers, as the nuclear waste contains a large portion of sea water. The generation of radiolysis gases may lead to a significant pressure build-up inside the containers and to the formation of flammable gases with the risk of ignition and the loss of integrity.In the framework of the project “R&D on technology for reducing concentration of flammable gases generated in long-term waste storage containers” funded by the Japanese Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT), the potential application of catalytic recombiner devices inside the storage containers is investigated. In this context, a suitable catalyst based on the so-called intelligent automotive catalyst for use in a recombiner is under consideration. The catalyst is originally developed and mass-produced for automotive exhaust gas purification, and is characterized by having a self-healing function of precious metals (Pd, Pt and Rh) dissolved as a solid solution in the perovskite type oxides. The basic features of this catalyst have been tested in an experimental program. The test series in the REKO-4 facility has revealed the basic characteristics of the catalyst required for designing the recombiner system. 相似文献
46.
Kei Noda Ko Okamura Junko Taniguchi Masaru Suzuki Mitsunori Hieda 《Journal of Low Temperature Physics》2013,171(5-6):638-643
We have carried out quartz crystal microbalance (QCM) experiments for 4He films on an exfoliated single-crystalline graphite using a 32 kHz tuning fork, and have measured the temperature dependence of the resonance frequency and the Q value for various areal densities and oscillation amplitudes. Comparing with the previous experiments for Grafoil, the decoupling of the films due to the slippage or the superfluidity was larger than that of Grafoil, and the competition between the slippage and the superfluidity was observed in three-atom thick films. Furthermore, it was found that the slippage is suppressed gradually at higher temperature than the superfluid onset T c , and that the relaxation time decreases at low temperatures while it obeys the Arrhenius law at high temperatures. These results suggest a precursor to the superfluidity of 4He films. 相似文献
47.
Caifang Gao Mu-Pai Lee Mengjiao Li Ko-Chun Lee Feng-Shou Yang Che-Yi Lin Kenji Watanabe Takashi Taniguchi Po-Wen Chiu Chen-Hsin Lien Wen-Wei Wu Shu-Ping Lin Wenwu Li Yen-Fu Lin Junhao Chu 《Advanced functional materials》2021,31(5):2005182
The human brain is often likened to an incredibly complex and intricate computer, rather than electrical devices, consisting of billions of neuronal cells connected by synapses. Different brain circuits are responsible for coordinating and performing specific functions. The reward pathway of the synaptic plasticity in the brain is strongly related to the features of both drug addiction and relief. In the current study, a synaptic device based on layered hafnium disulfide (HfS2) is developed for the first time, to emulate the behavioral mechanisms of drug dosage modulation for neuroplasticity. A strong gate-dependent persistent photocurrent is observed, arising from the modulation of substrate-trapping events. By controlling the polarity of gate voltage, the basic functions of biological synapses are realized under a range of light spiking conditions. Furthermore, under the control of detrapping/trapping events at the HfS2/SiO2 interface, positive/negative correlations of the An/A1 index, which significantly reflected the weight change of synaptic plasticity, are realized under the same stimulation conditions for the emulation of the drug-related addition/relief behaviors in the brain. The findings provide a new advance for mimicking human brain plasticity. 相似文献
48.
49.
Shunsuke Kato Prof. Akira Onoda Naomasa Taniguchi Prof. Ulrich Schwaneberg Prof. Takashi Hayashi 《Chembiochem : a European journal of chemical biology》2021,22(4):679-685
Directed evolution of Cp*RhIII-linked nitrobindin (NB), a biohybrid catalyst, was performed based on an in vitro screening approach. A key aspect of this effort was the establishment of a high-throughput screening (HTS) platform that involves an affinity purification step employing a starch-agarose resin for a maltose binding protein (MBP) tag. The HTS platform enables efficient preparation of the purified MBP-tagged biohybrid catalysts in a 96-well format and eliminates background influence of the host E. coli cells. Three rounds of directed evolution and screening of more than 4000 clones yielded a Cp*RhIII-linked NB(T98H/L100K/K127E) variant with a 4.9-fold enhanced activity for the cycloaddition of acetophenone oximes with alkynes. It is confirmed that this HTS platform for directed evolution provides an efficient strategy for generating highly active biohybrid catalysts incorporating a synthetic metal cofactor. 相似文献
50.
Ayako Sakai Yoko Yamakoshi Naoki Miyata 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(5):743-756
Abstract Cell transformation in vitro is a model of carcinogenesis in vivo. Two-stage transformation assay increases the sensitivity of cells to chemicals and permits detection of carcinogens acting as initiating agents. [60]Fullerene (C60) was cytotoxic in BALB/3T3 cells when it was irradiated by visible light, but not without light irradiation. Under conditions when C60 was cytotoxic, it acted as an initiating agent for cell transformation, but it did not act as a complete transforming agent. the initiating activity of visible-light-irradiated C60 was statistically significant in a modified two-stage transformation assay including a procedure for replating cells treated by C60 and light, but it was equivocal in the standard two-stage transformation assay. 相似文献