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131.
Toshie Tahara Yoshitsugu Sakuda Mitsuaki Kodama Yoshimasa Fukazawa Shô Itô Kazuyoshi Kawazu Shuhei Nakajima 《Tetrahedron letters》1980,21(19):1861-1862
The structures of xantholides A and B were deduced on the basis of IR and NMR spectra, and confirmed by X-ray analysis. Xantholide A inhibited the larval growth of Drosophila melanogaster. 相似文献
132.
133.
Hiroyuki Inouye Yoshio Takeda Shinichi Uesato Kenichi Uobe Toshiro Hashimoto Tetsuro Shingu 《Tetrahedron letters》1980,21(11):1059-1062
Hydrangenoside A, isolated along with its three congeners from Hydrangea macrophylla, was proved to have a novel type of structure which is thought to be biosynthesized through an aldol-type condensation of secologanin with a unit formed by the shikimate-malonate route followed by decarboxylation. 相似文献
134.
We have measured luminescence spectra of 2H-PbI2 at different temperatures between 77 and 180 K. The lower energy tail of the luminescence band due to free exciton annihilation decreases exponentially with decreasing the photon energy over an order of magnitude, which corresponds to the Urbach tail in the absorption spectrum. This fact suggests that the exciton state corresponding to the exponential tail is in the thermal equilibrium and the steepness coefficient δ0 = 1.67 in Urbach rule is obtained also from the luminescence spectra. 相似文献
135.
136.
This paper describes a novel, sensitive detection system for biomolecules (DNA and proteins etc.) that is integrated in a lab-on-a-chip utilizing optical compact discs (CDs) and bio-nanofibers. The new method comprises a microchannel containing CD grating that confines fragments of unique bacterial cellulose fibrils (BC), which have nanometre scale fibers and holes. A maximum of six times higher sensitivity to detect DNA was obtained with this CD and BC system compared to a conventional method. We also demonstrate an effective light-confining effect for biological application with the new method. 相似文献
137.
Treatment of 1,1-dichloroalk-1-enes with Cp2Ti[P(OEt)3]2 produced organotitanium species, which afford allenes on treatment with aldehydes and ketones. 相似文献
138.
Ikuma N Tsue H Tsue N Shimono S Uchida Y Masaki K Matsuoka N Tamura R 《Organic letters》2005,7(9):1797-1800
[reaction: see text] Enantiomerically enriched samples of chiral cyclic nitroxides with a 4-hydroxyphenyl group on the stereogenic center bearing the NO radical group undergo unprecedented spontaneous racemization and/or epimerization in aprotic solvents, which can be well accounted for by the multistep equilibrations involving planar quinoid intermediates. 相似文献
139.
Yoshida Y Tateiwa N Mito M Kawae T Takeda K Hosokoshi Y Inoue K 《Physical review letters》2005,94(3):037203
We have measured the specific heat of an S = 1/2 antiferromagnetic alternating Heisenberg chain pentafulorophenyl nitronyl nitroxide in magnetic fields up to H > H(C2). This compound has a field-induced magnetic ordered (FIMO) phase between H(C1) and H(C2). Characteristic behaviors are observed depending on the magnetic field up to above H(C2) outside of the H-T boundary for the FIMO. The temperature and field dependence of the specific heat are qualitatively in good agreement with the theoretical calculation on an S = 1/2 two-leg ladder [Wang et al., Phys. Rev. Lett. 84, 5399 (2000)]]. This agreement suggests that the observed behaviors are related with the low-energy excitation in the Tomonaga-Luttinger liquid. 相似文献
140.
Tavrov AV Kobayashi Y Tanaka Y Shioda T Otani Y Kurokawa T Takeda M 《Optics letters》2005,30(17):2224-2226
A three-dimensional common-path interferometer is proposed, which can achromatically null out an on-axis source while it maintains the detectability of an off-axis source. A geometric phase in the three-dimensional interferometer introduces an achromatic pi-phase shift to the light from the on-axis source, such that destructive interference nulls out the axial light at one of the ports of the interferometer. Light from the off-axis source, which is exempt from the pi-phase shift, comes out from both ports with equal intensity. The common-path scheme makes the system highly immune to environmental disturbances. 相似文献