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31.
S. Mukai P. Phelan M. Watanabe H. Itoh H. Yajima 《Optical and Quantum Electronics》1989,21(3):227-231
A new technique for scanning a diode laser beam is introduced where the beam is deflected in a current-injection-type travelling-wave beam deflector integrated with a diode laser. The deflector, which is formed outside the laser cavity, is cleave-coupled to the cavity. An anti-reflection coating on the deflector output facet suppresses the light returning to the laser. As a result, very smooth deflection of the radiation peak with low background intensity is realized in this device, while retaining high efficiency and low threshold current. 相似文献
32.
Kenji Yajima 《Communications in Mathematical Physics》1980,75(2):153-178
Scattering theory for time dependent HamiltonianH(t)=?(1/2) Δ+ΣV j (x?q j (t)) is discussed. The existence, asymptotic orthogonality and the asymptotic completeness of the multi-channel wave operators are obtained under the conditions that the potentials are short range: |V j (x)|≦C j (1+|x|)?2?ε, roughly spoken; and the trajectoriesq j (t) are straight lines at remote past and far future, and |q j (t)?q k (t)| → ∞ ast → ± ∞ (j≠k). 相似文献
33.
Shimazaki Y Tashiro M Motoyama T Iwatsuki S Yajima T Nakabayashi Y Naruta Y Yamauchi O 《Inorganic chemistry》2005,44(17):6044-6051
Synthetic, structural, spectroscopic, and kinetic studies have been carried out on the Pd(II) complexes of new 2N1O-donor ligands containing a pendent indole, 3-(N-2-pyridylmethyl-N-2-hydroxy-5-methoxybenzylamino)ethylindole (HMeO-iepp), 3-(N-2-pyridylmethyl-N-2-hydroxy-5-nitrobenzylamino)ethylindole (HNO2-iepp), and (N-2-pyridylmethyl-3-indolylethylamino)acetic acid (Hiepc) (H denotes a dissociable proton). [Pd(MeO-iepp)Cl] (2), [Pd(NO2-iepp)Cl] (3), and [Pd(iepc)Cl] (4) were prepared and revealed by X-ray analysis to have a pyridine nitrogen, an amine nitrogen, a phenolate or carboxylate oxygen, and a chloride ion in the coordination plane. UV absorption and 1H NMR spectral changes indicated that all the complexes could be converted to the indole-binding complexes where the O donor was replaced by the indole C2 atom by cyclopalladation in DMSO or DMF in the temperature range of 40-60 degrees C. Formation of the indole-binding complex species obeyed the first-order kinetics, from which the activation parameters were estimated. The formation rate was dependent on the properties of the O-donor group, a lower pKa value of its conjugate acid causing faster conversion to the indole-binding species in the order 2 (methoxyphenolate) < 3 (nitrophenolate) < 4 (carboxylate). On the other hand, the ratio of the indole-binding complex to the O-donor complex as a result of the conversion was greater for the complexes with a higher pKa value of the ligand OH group, the order being 2 > 3 > 4. 相似文献
34.
The reactions of three aromatic hydrocarbons, benzene, toluene, and styrene, with oxygen in a radiofrequency (r) plasma were investigated. Benzene was oxidized to yield phenol as a single volatile organic product. Similarly, toluene gave the ring oxidation products, cresols, as well as considerable amounts of methyl oxidation products, consisting mainly of benzaldehyde and benzyl alcohol. In contrast, the oxidation of styrene took place predominantly on the olefinic double bond to produce styrene oxide On basis of the products and effects of reaction variables, r power and flow rates of hydrocarbons and oxygen, on the reaction rate, the oxidation mechanism was discussed, particularly focusing on the intermediate species responsible for the formation of major products. 相似文献
35.
Masashi Ohkawa Yuki Shirai Takeshi Goto Seishi Sekine Takashi Sato 《Fiber and Integrated Optics》2002,21(2):105-113
In this paper, a silicon-based integrated optic pressure sensor using an intermodal interference between the fundamental TM-like and TE-like modes is described. The sensor consists of a micromachined rectangular diaphragm and a straight polystyrene optical waveguide passing over the diaphragm. Its sensitivity is theoretically known to be strongly dependent on the position of the waveguide over the diaphragm. To experimentally investigate such dependence, we fabricated a sensor with a 1.2 mm ×10 mm ×20 μm diaphragm, over which waveguides were placed at 50 μm intervals. The measured phase sensitivity was 98 mrad/kPa for the waveguide nearest to the diaphragm edge. The measurement was also carried out for the other waveguides. As theoretically expected, the largest sensitivity was obtained for the waveguide nearest to the edge. 相似文献
36.
A proposed structure for the diffusible extracellular factor (DF) of Xanthomonas campestris pv. campestris (Xcc) has been synthesized. Its MS spectrum and biological activity, however, contradict those of the natural product previously reported, suggesting that the structure for DF of Xcc must be reexamined. 相似文献
37.
Hideaki Ichiba Mio Nakamoto Takehiko Yajima Mitsuo Takayama Takeshi Fukushima 《Biomedical chromatography : BMC》2010,24(2):140-147
The C‐terminal octapeptide of cholecystokinin (CCK8) includes some easily oxidizable amino acids. The oxidation of CCK8 by reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and hydroxyl radicals (OH?) was investigated using reversed‐phase high performance liquid chromatography (RP‐HPLC) and subsequent electrospray ionization mass spectrometry. The mechanism of oxidation of CCK8 in the H2O2 system differed from that of CCK8 in the Fenton system, in which OH? are produced. In the H2O2 system, 28Met and 31Met were oxidized to methionine sulfoxide, and no further oxidation or degradation/hydrolysis occurred. On the other hand, in the Fenton system, 28Met and 31Met residues were oxidized to methionine sulfone via the formation of methionine sulfoxide. In addition, the oxidized product was observed at the Trp residue but not at the Tyr residue, and small peptide fragments from CCK8 were observed in the Fenton system. From these results, it was concluded that 28Met and 31Met residues of CCK8 are susceptible to oxidation by ROS. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
38.
A high-speed photographic study of the transition from deflagration to detonation wave 总被引:2,自引:0,他引:2
Experiments were conducted to investigate the DDT process of the oxyhydrogen gas in the rectangular detonation tube of 3 m
long. The repeated obstacle was installed near the ignition plug and the effects of the obstacle on the DDT process were investigated.
The behaviour of the combustion and detonation wave were visualized utilizing Imacon high-speed camera with the aid of Schlieren
optics.
As a result, DDT process was visualized, i.e. (i) multiple shock waves were induced by the expanding combustion wave, because
the combustion flame played a role as a piston and compressed the unburned gases. (ii) The acceleration of the combustion
wave was occurred and the distance between the shock wave and the combustion flame became shorter. (iii) Eventually, the local
explosion was occurred and cause overdriven detonation wave to propagate at the velocity of about 3 kms−1.
An abridged version of this paper was presented at the 15th Int. Colloquium on the Dynamics of Explosions and Reactive Systems
at Boulder, Colorado, from July 30 to August 4, 1995 相似文献
39.
In the present paper, the buckling behavior of clamped thin shallow spherical shells under external pressure is studied. Seventy-nine plastic shells formed by thermovacuum process were tested. The distributions of initial geometrical imperfections and vertical displacements were minutely measured with a differential transformer. It was possible to control the symmetrical initial geometrical imperfection of each specimen.Results indicate that the buckling phenomena of shallow spherical shells vary greatly with the symmetrical initial imperfection parameter η. In the case of the geometrical parameter λ larger than 5.5, the amplitude of the asymmetrical displacement component with the bifurcation buckling wave calculated by Huang becomes large immediately before buckling. The validity of Huang's theory for an initially perfect shell is experimentally demonstrated. 相似文献
40.
Yukinobu Yajima 《Topology and its Applications》2011,158(15):2085-2089
Let S be the class of all spaces, each of which is homeomorphic to a stationary subset of a regular uncountable cardinal (depending on the space). In this paper, we prove the following result: The product X×C of a monotonically normal space X and a compact space C is normal if and only if S×C is normal for each closed subspace S in X belonging to S. As a corollary, we obtain the following result: If the product of a monotonically normal space and a compact space is orthocompact, then it is normal. 相似文献