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991.
992.
The time dependence of microwave absorption was measured for the J = 2-1 and J = 3-2 transitions of OCS under on- and off-resonant conditions utilizing Stark and source modulation, respectively. The two effective pressure parameters obtained under the two conditions, which correspond to and , respectively, according to the Bloch equation, are different beyond experimental error; the difference is 0.94 ± 0.38 (2.5σ) MHz/Torr for J = 2?1. This difference was also determined to be 1.19 ± 0.30 MHz/Torr from the dependence of the nutation frequency on the microwave power. 相似文献
993.
994.
995.
996.
Keiichi Nagai Kentarou Kawaguchi Chikashi Yamada Kazuo Hayakawa Yoshihiro Takagi Eizi Hirota 《Journal of Molecular Spectroscopy》1980,84(1):197-203
We construct a high-precision wavelength meter for infrared tunable diode lasers (TDL) which consists of moving corner reflectors forming a Michelson interferometer, with a single-frequency HeNe laser as a standard. The design of the wavelength meter is described in detail, and possible sources of errors are discussed. An absolute accuracy of 10?7 is demonstrated by measuring CO2 laser wavelengths and almost the same order of accuracy is achieved by applying the wavelength meter to the ν1 band of N2O observed by a TDL. 相似文献
997.
Takushi Kurihara Keizo Fukunaga Toshiko Sakaguchi Hiroshi Hirano 《Journal of heterocyclic chemistry》1975,12(5):989-993
The reaction of iminoether III with benzyl cyanoacetate gave ethyl 1-(α-cyanocarbobenzyl-oxymethylene)isoindoline-3-acetate (V) in a 26% yield. Decarboxylation of ethyl 1-(α-cyanocarboxymethylene)isoindoline-3-acetate (VI), obtained by hydrogenolysis of V, gave a mixture of 1-carboethoxymethyleneisoindoline-3-acetonitrile (VII) as major component and 1-carboethoxymethylene-3-cyanomethyleneisoindoline (VIII) as minor component, which were reconvertible into each other. On the other hand, decarboxylation of VI was successfully carried out to give VII as a single product under a nitrogen atmosphere. Ethanolysis and autoxidation of VII gave crystalline diethyl 1,3-dicarboethoxymethyleneisoindoline (XIII). Catalytic hydrogenation of of XIII over platinum oxide gave diethyl isoindoline-cis-1,3-diacetate (XIV) in a yield of 92%. The uv spectra of these 1,3-disubstituted isoindoline derivatives are summarized in Table I. 相似文献
998.
999.
Keiichi MinamiAkitoshi Hayashi Satoshi UjiieMasahiro Tatsumisago 《Solid State Ionics》2011,192(1):122-125
Electrical and electrochemical properties of the 70Li2S·(30 − x)P2S5·xP2S3 and the 70Li2S·(30 − x)P2S5·xP2O5 (mol%) glass-ceramics prepared by the mechanical milling technique were investigated. Glass-ceramics with 1 mol% P2S3 and 3 mol% P2O5 showed the highest conductivity of 5.4 × 10− 3 S cm− 1 and 4.6 × 10− 3 S cm− 1, respectively. Moreover, these glass-ceramics showed higher electrochemical stability than the 70Li2S·30P2S5 (mol%) glass-ceramic. From the XRD patterns of the obtained glass-ceramics, trivalent phosphorus and oxygen were incorporated into the Li7P3S11 crystal. We therefore presume that the Li7P3S11 analogous crystals, which were formed by incorporating trivalent phosphorus and oxygen into the Li7P3S11 crystal, improve the electrical and electrochemical properties of the glass-ceramics. An all-solid-state cell using the 70Li2S·29P2S5·1P2S3 (mol%) glass-ceramic as solid electrolyte operated under the high current density of 12.7 mA cm− 2 at the high temperature of 100 °C. The cell showed an excellent cyclability of over 700 cycles without capacity loss. 相似文献
1000.
We propose a novel flat optical frequency comb generation system that employs fiber loop modulation and experimentally demonstrate
its operation. Generally, when an external laser beam is injected into a fiber loop system including an optical modulator
and an amplifying medium, multiple sidebands are generated exponentially. On the other hand, the fiber loop starts mode-locked
oscillation at a center frequency to maximize the round-trip gain in the fiber loop from the seeds of the injected laser sidebands.
By locking the sidebands from fiber loop modulation with the mode-locked oscillation in the fiber loop, the synchronous spectrum
between the mode-locked oscillation and the sidebands can be shaped into a flat spectrum. Thus, a flat optical frequency comb
with a flatness of about ±1 dB is obtained in the spectral bandwidth of about 1 THz. 相似文献