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排序方式: 共有167条查询结果,搜索用时 62 毫秒
91.
Tsuneo Fujii Shozi Mishima Nobuaki Tanaka Osamu Kawauchi Kazuhiko Kodaira Hiromasa Nishikiori Yoshinobu Kawai 《Research on Chemical Intermediates》1997,23(9):829-839
The absorption, fluorescence, and fluorescence-excitation spectra of 9-anthrol (and/or anthrone) have been observed in various
solvents, one of which includes a silicon-aluminium ester (diisobutoxyaluminium triethyl silane[(OBu)2−Al−O−Si−(OEt)3 SAE]). The fluorescence spectra of 9-anthrol shows peak wavelengths at 442 nm in benzene, 454 nm in methanol, 539 nm in triethylamine,
and 550 nm in basic solution, which can be assigned to a neutral, a hydrogen-bonded neutral, an ion pair, and an anionic species
of 9-anthrol, respectively. In ethanol solution including SAE, on the other hand, a new fluorescence peak appears at 473 nm.
This new band originates from a complex formed between 9-anthrol and SAE. The excited-state ion pair is formed through the
hydrogen-bonded form in water and the complex form in triethylamine. CNDO/S calculations support the experimental results. 相似文献
92.
Hiroyuki Takemura Saori Nakata Akiko Inoue Ayaka Mishima 《Journal of inclusion phenomena and macrocyclic chemistry》2013,77(1-4):483-487
A polycationic cyclophane with six cationic sites (three 4,4′-bipyridinium cation units) supported by a rigid cyclic skeleton was synthesized. It formed electron donor–acceptor complexes with electron-rich compounds, and their inclusion properties with pyrene and calixresorcin[4]arene were studied. 相似文献
93.
J. Allam N. de B. Baynes J. R. A. Cleaver K. Ogawa T. Mishima I. Ohbu 《Optical and Quantum Electronics》1996,28(7):875-896
An integrated optoelectronic circuit for ultrafast sampling of multi-terminal devices is described. This is achieved using optimized photoconductive switches fabricated from low-temperature-grown GaAs, monolithic integration of the device with the sampling circuit, control of the electromagnetic modes propagating on the coplanar waveguide using microfabricated airbridges, and discrimination of guided and freely-propagating modes using a novel electrooptic sampling method. As an example, the scattering parameters associated with the propagation of a picosecond pulse through one of the gates of a dual-gate heterojunction field-effect transistor are obtained at frequencies up to 300 GHz. The inter-gate capacitance is determined by measuring the electromagnetic transient coupled between the gates. 相似文献
94.
Teruhito Mishima 《Optical Review》1995,2(5):383-387
Self-pumped four wave mixing (SPFWM) in single BaTiO3 crystal is experimentally studied because of its fast response and rather simple optical system. The origins of unstable operations are shown and classified: unstable operation of self-pumped phase conjugate mirror (SPPCM), floating dust in the laser beam path, competition between beam path loops, and competition between groups of index gratings. The reflectivities and the buildup times are measured as they relate to incident conditions, i.e. the geometry of beam paths and interaction regions, and four cases are given. Large reflectivity was obtained when buildup time was short, probably because of large coupling strength. The measured buildup times lie between 0.5 s and 0.6 s at the total incident beam power of about 5.5 mW, so that fast response of SPFWM was confirmed. 相似文献
95.
Takehiro Yoshida Yuichi Oshima Takeshi Eri Ken Ikeda Shunsuke Yamamoto Kazutoshi Watanabe Masatomo Shibata Tomoyoshi Mishima 《Journal of Crystal Growth》2008,310(1):5-7
By using the hydride vapor phase epitaxy and a void-assisted separation method, freestanding 3-in GaN substrates were successfully fabricated for the first time, and the process showed an excellent reproducibility. A thick GaN layer 3.2 in in diameter was easily separated from the base substrate. No cracks were generated during the separation process. The dislocation density was of the order of 106 cm–2. The carrier density was approximately 1×1018 cm–3 and the mobility was 3.4×102 cm2 V–1 s–1. The concentrations of impurities, estimated by secondary-ion mass spectrometry, were below the limit of detection, except for Si. The Si concentration was approximately 1×1018 cm–3, which is in good agreement with the carrier density. 相似文献
96.
Our generalized Keldysh theory is applied to the simplest many-electron atom, helium atom. For the single ionization (He-->He(+)+e) we derive a compact rate formula, which does not contain any series summation or integral and thus is as simple as the Ammosov-Delone-Krainov ionization rates. In addition to its simplicity, our formula can explicitly show the wavelength dependence. Furthermore a simple form of the angular distribution of the photoelectron is available. Our compact formula agrees well with both the exact numerical calculations [A. Scrinzi et al., Phys. Rev. Lett. 83, 706 (1999)] and experimental data [B. Walker et al., Phys. Rev. Lett. 73, 1227 (1994)] in the intensity range of I<5x10(15) Wcm(2). In higher intensity regions, we suggest to utilize another simple formula which is valid in the tunneling limit. 相似文献
97.
The structure of a strange attractor of the two-dimensional cubic map with jacobian J is investigated in the cases J ≈ 0 and J ≈ 1. The strange attractor has a selfsimilar three-belt structure. The threshold of homoclinic bifurcation is calculated for J ≈ 1. 相似文献
98.
Myelin figures were found to form at the main phase transition temperatures of several phospholipids for various ph values and Ca2+ concentrations. The optical observation of myelin figure formation provides a simple method of detecting the phase transition of phospholipids. 相似文献
99.
Ce3+—高分子络合物发光的激发过程 总被引:1,自引:0,他引:1
本文研究了Ce3+-PMMA及Ce3+—PMA18·C·6两个高分子络合物发光材料的荧光激发过程以及激发过程与高分子结构的关系。通过荧光寿命、荧光光谱以及时间分辨光谱分析表明,在Ce3+—PMMA络合物体系中,Ce3+的荧光发射主要是来自高分子配体的能量传递,而对于Ce3+—PMA18·C·6粉末络合物体系,Ce3+发光的能量主要是来自入射光的直接激发。文章对上述两个稀土高分子络合物的激发机制的差异也做了较为详细地描述。 相似文献
100.