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排序方式: 共有181条查询结果,搜索用时 15 毫秒
121.
Yuki Obama Yusaku Sakurai Takenori Kitazawa Shu Hotta 《Molecular Crystals and Liquid Crystals》2016,629(1):218-223
We fabricated organic light-emitting transistors (OLETs) characterized by an Ag layer deposited on a one-dimensional (1D) or two-dimensional (2D) diffraction grating that acts as a combined gate insulator with SiO2. The Ag layer was entirely covered with an organic crystal. Upon photoexcitation that crystal showed narrow linewidth emissions (NLEs) parallel to the substrate plane. The narrowed lines were either redshifted or blueshifted with rotation of the crystal around a normal to its surface with respect to the grating wave vector. Strong emissions (~104–106 cd m?2) accompanied by current-injected NLEs were observed from the 1D and 2D grating OLETs. 相似文献
122.
Yusaku Yamamoto 《Applications of Mathematics》2017,62(4):319-331
Lower bounds on the smallest eigenvalue of a symmetric positive definite matrix A ∈ R m×m play an important role in condition number estimation and in iterative methods for singular value computation. In particular, the bounds based on Tr(A ?1) and Tr(A ?2) have attracted attention recently, because they can be computed in O(m) operations when A is tridiagonal. In this paper, we focus on these bounds and investigate their properties in detail. First, we consider the problem of finding the optimal bound that can be computed solely from Tr(A ?1) and Tr(A ?2) and show that the so called Laguerre’s lower bound is the optimal one in terms of sharpness. Next, we study the gap between the Laguerre bound and the smallest eigenvalue. We characterize the situation in which the gap becomes largest in terms of the eigenvalue distribution of A and show that the gap becomes smallest when {Tr(A ?1)}2/Tr(A ?2) approaches 1 or m. These results will be useful, for example, in designing efficient shift strategies for singular value computation algorithms. 相似文献
123.
The PdII-catalyzed tandem cyclization of chiral allylic alcohols possessing an internal epoxide and a terminal alcohol provided a contiguous THF–THP and THF–THP ring units stereospecifically. The cyclizations take place via a 5-exo-tet-5-exo-trig mode, however, the cyclization of methyl substituted epoxy diols proceeded via 6-endo-tet-6-exo-trig fashion in a part to construct the oxygen-fused THP–THP ring. The different reaction rates of precursors, which are different stereochemistry at allylic alcohol have been elucidated. 相似文献
124.
125.
A laser Doppler velocimeter (LDV) for two-dimensional velocity measurement using a simple optical configuration without any optical modulator is proposed. The structure using polarized beams and the 90° phase shift of the reference beam is used to discriminate the direction of velocity. The analytical relation among beat frequencies and velocity components is derived and the characteristics of the proposed LDV are simulated. The simulation results indicate that the direction of velocity can be discriminated by the proposed LDV as well as the magnitudes of the components of the velocity. 相似文献
126.
Yoshiki Hidaka Yusaku Hosokawa Koyo Tamura Shoichi Kai 《Physica D: Nonlinear Phenomena》2010,239(11):735-728
Non-thermal Brownian motion of a particle for soft-mode turbulence (SMT) in the electroconvection of a nematic liquid crystal has been experimentally investigated to clarify the statistical and thermodynamical aspects of SMT, using the Lagrangian picture in hydrodynamics. The effective temperature for SMT is obtained in two different ways based on the Einstein relation and the fluctuation theorem from the diffusion due to non-thermal particle fluctuations. The temperatures from the two methods agree well and exhibit a high value of 106 K. They depend on the coarse-graining time, which reflects the anomalous properties of the macroscopic fluctuations for the SMT. 相似文献
127.
128.
T. Kinoshita H. Yamazaki H. Fukasawa K. Hirota T. Ishikawa J. Kasagi A. Kato T. Katsuyama K. Kino F. Miyahara T. Nakabayashi K. Nawa K. Okamura Y. Saitoh K. Satou M. Sengoku H. Shimizu K. Suzuki S. Suzuki T. Terasawa H. Kanda K. Maeda T. Takahashi Y. Aruga T. Fujinoya A. Iijima M. Itaya Y. Ito T. Iwata H. Kato T. Kawamura T. Michigami M. Moriya T. Sasaki Y. Tajima S. Takita T. Noma M. Yamamoto H.Y. Yoshida Y. Yoshida O. Konno T. Maruyama T. Yorita 《Physics letters. [Part B]》2006
129.
F.Miyahara H.Fukasawa R.Hashimoto T.Ishikawa M.Itoh T.Iwata H.Kanda J.Kasagi H.Kato T.Kinoshita K.Maeda M.Matsuzawa T.Michigami K.Motiduki K.Murakami T.Nakabayashi K.Nawa T.Nomura K.Okamura H.Okamura H.Okuyama Y.Onodera Y.Saito T.Sasaki H.Shirnizu T.Shishido S.Suzuki K.Suzuki Y.Tajima S.Takita T.Takahashi H.Ueno S.Yamaguchi H.Yamazaki H.Y.Yoshida 《原子核物理评论》2009,26(Z1)
Differential and total cross sections of the γp→π~0 p and the γp→π~0 pn reaction were measured for photon energies between 640 and 1 150 MeV.The data have been compared with SAID and MAID model calculations.π~0 photoproduction on the deuteron shows a strong suppression of the 2nd resonance which is clearly seen in the γp→π~0 p reaction. 相似文献
130.
T. Shimozuma S. Morimoto M. Sato Y. Takita S. Ito S. Kubo H. Idei K. Ohkubo T. Watari 《International Journal of Infrared and Millimeter Waves》1997,18(8):1479-1493
Silicon nitride composite as a candidate of a window material for high power CW (Continuous Wave) millimeter-waves was high
power tested especially with a surface cooling by impinging gas nitrogen jets on the single-disk surface. Gas-cooling dramatically
suppressed the temperature of the window disk even with gas flow rate of around 100 l/min. With gas cooling of 465l/min.,
130kW CW power of HE11 mode could be transmitted through the silicon nitride window with a diameter of 88.9mm. The peak window temperature was completely
saturated on 123.6 °C. Without gas-cooling it did not saturate and reached 323 °C during 30 seconds pulse. A possibility of
1MW CW single disk Brewster windows with a forced gas-cooling is discussed, resulting in convinced prospects of the windows
with realistic size and thickness. 相似文献