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991.
992.
993.
Successive laser emission at 337.1 nm and 357.7 nm in the second positive band of N2 have been observed in high-pressure Ar-N2 gas mixtures excited by a high current (15 kA) and fast rise time (8 ns) relativistic electron beam. Laser action at 357.7 nm was confirmed in the pressure range 450–6000 torr where output intensity was approximately independent of pressure, while strong pressure dependence of the emission at 337.1 nm was observed in a rather limited pressure range of 760–3000 torr. From the results of spectrally resolved pressure dependences of the laser lines, the processes of successive laser oscillation at these two wavelengths are discussed. 相似文献
994.
Osamu Suekane Shigehiko Hasegawa Masakazu Tanaka Toshiko Okui Hisao Nakashima 《Applied Surface Science》2002,190(1-4):218-221
Post-annealing effects on InAs islands grown on GaAs(0 0 1) surfaces have been investigated by scanning tunneling microscopy (STM) connected to molecular beam epitaxy (MBE). It is found that for islands grown by 1.6 ML InAs deposition at 450 °C, post-annealing at 450 °C in an As4 atmosphere causes dissolving of the InAs islands. In contrast, for larger islands obtained by 2.0 ML InAs deposition at 450 °C, the post-annealing leads to coarsening of the islands. The result can be explained in terms of a critical nucleus in heterogeneous nucleation. 相似文献
995.
Hanaizumi Osamu Saito Makoto Ohtera Yasuo Kawakami Shojiro Yano Satoshi Segawa Yusaburo Kuramochi Eiichi Tamamura Toshiaki Oku Satoshi Ozawa Akira 《Optical and Quantum Electronics》2002,34(1-3):71-77
SiO2/air three-dimensional (3D) periodic structures were fabricated by removing Si layers partially from Si/SiO2 3D photonic crystals (PhCs) formed by using autocloning. CdS/SiO2 3D periodic structures were formed by introducing CdS into the SiO2/air structures by the TEA method and photoluminescence (PL) was observed from the introduced CdS. TiO2/air/CdS two-dimensional (2D) PhCs were also fabricated by introducing CdS into the voids of TiO2/air 2D periodic structures, in which SiO2 layers were partially etched out from TiO2/SiO2 2D PhCs fabricated by using autocloning. PL radiating normal to the surface was measured and large polarization dependence was observed. 相似文献
996.
997.
Shigenobu Hayashi Kikuko Hayamizu Osamu Yamamoto 《Journal of Physics and Chemistry of Solids》1983,44(6):601-606
The behavior of hydrogen in the hydrides of vanadium metal containing small amounts of nickel was studied by 1H NMR spectroscopy. FT spectra and spin-spin and spin-lattice relaxation times for VH0.77, V0.95Ni0.05H0.73, and V0.90Ni0.10H0.65 were measured at temperatures between 77 and 400 K. On the addition of nickel the number of hydrogen atoms on O22 sites decreases and the superstructure of hydrogen is altered. Different effects of nickel on hydrogen diffusion are observed above and below about 200 K, and, therefore, the mechanism of hydrogen diffusion is assumed to change at this temperature. 相似文献
998.
999.
Osamu Kobayashi 《Mathematische Annalen》1987,279(2):253-265
1000.
Kazunori Matsumura Kikuko Hayamizu Takashi Nakane Hiroshi Yanagishita Osamu Yamamoto 《Journal of Polymer Science.Polymer Physics》1988,26(11):2215-2227
1H- and 2H-NMR spectra of water (H2O and D2O) and methanol (CH3OD and CD3OH) absorbed in cellulose triacetate films have been observed as a function of the angle θ between the film surface and the magnetic field. 1H-NMR signals of H2O and CH3OD are doublets and triplets due to dipole interactions, respectively. 2H-NMR signals of D2O, CD3OH, and CH3OD are doublets due to quadrupole splittings. The magnitudes of these splittings change depending on θ. The analysis of the angle-dependent patterns indicates that the motionally averaged axes of the dipole and the quadrupole moments orient in the direction perpendicular to the film surface. The alignment of water and/or methanol molecules originates from the film morphology, which is anisotropic in the perpendicular direction. From the angle dependence of the chemical shift, the volume diamagnetic susceptibility of the film is estimated to be 0.44 ppm. 相似文献