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151.
Takeharu Innami Ryushi Fujimura Masahiro Nomura Tsutomu Shimura Kazuo Kuroda 《Optical Review》2005,12(6):448-450
The photorefractive effect was observed in He-ion-implanted semi-insulating GaN film in the UV spectral region. The photorefractive
grating is induced by the electroabsorption effect near the band-edge. Two beam coupling experiments were performed at a wavelength
of 363.8 nm. The experimental results indicate that absorption grating mainly contributes to the beam coupling. 相似文献
152.
153.
Yoshitane Imai Kensaku Kamon Nobuo Tajima Reiko Kuroda Yoshio Matsubara 《Tetrahedron》2007,63(48):11928-11932
Chiral charge-transfer (CT) complexes composed of a chiral 1,1′-bi-2-naphthol cluster as the electron donor and 1,1′-dibenzyl-4,4′-bipyridinium dichloride as the electron acceptor serve as a host system for molecular recognition. CT complexes that include guest alcohols show different diffuse reflectance spectra (DRS) depending on the included guest. 相似文献
154.
Motoo Tori Aki Watanabe Yasuko Okamoto Shigeru Takaoka Chiaki Kuroda Ryo Hanai 《Tetrahedron》2008,64(19):4486-4495
Twenty-six eremophilane-type sesquiterpenoids, including six new compounds, were isolated from the title species. One of the new compounds, kanaitzensol, suggested the presence of an enzyme for the conversion of eremophil-7(11)-en-8-one derivative to furanoeremophilanes. The plant was collected at 15 locations in Yunnan Province of China and found to be diverse with respect to its sesquiterpenoid composition. DNA sequencing also revealed a large intraspecific diversity of the plant. 相似文献
155.
156.
Urea (U) and salicylic acid (SA) crystallize from aqueous solution as a 11 adduct whose structure shows them to be linked via several weak and one strong hydrogen bonds. The ir spectra of the adduct and its deuterated counterpart have been analyzed and the stretching modes of the various hydrogen bonds identified. The1H and13C nmr. spectra are also interpreted to show that discrete adducts of U·SA persist in solution. On heating, U·SA decarboxylates at a much lower temperature than SA itself. 相似文献
157.
158.
Boric acid was trimethylsilylated with Me3SiCl/(Me3Si)2O in the presence of 2-propanol. The resulting mixture was analysed by using a combi 相似文献
159.
160.
The fluorescence lifetime τ1 of Pr3+ doped in the ferroelectric solid solution SNB40 (Ba0.4Sr0.6Nb2O6) was measured ar various temperatures. The fluorescence lifetime decreases gradually with increasing temperature. Furthermore, an anomalous increase of τ1 was observed at a specific temperature. The fluorescence linewidth and the peak wavelength of fluorescence also showed an anomalous change at this temperature. It is likely that this phenomenon is due to the phase transition of the host crystal SBN40. 相似文献