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181.
Measurement of spatial coherence of a copper vapour laser beam using a reversal shear interferometer
T. Omatsu K. Kuroda T. Shimura K. Chihara M. Itoh I. Ogura 《Optical and Quantum Electronics》1991,23(4):S477-S484
We measured the spatial coherernce of a copper vapour laser (CVL) beam with an unstable resonator by the reversal shear interferometer. By this method, we can evaluate the spatial coherence function from a single-shot measurement. The spatial coherence width was 5 mm when an unstable resonator with a magnification factor of 60 was used. Moreover we verified the result by the theoretical calculation on the basis of the passive resonator model. 相似文献
182.
H Tsujibo T Sakamoto K Miyamoto G Kusano M Ogura T Hasegawa Y Inamori 《Chemical & pharmaceutical bulletin》1990,38(8):2299-2300
An alkalophilic actinomycete, strain OPC-553 regarded as Nocardiopsis dassonvillei subsp. prasina, produced the cytotoxic substance, TS-1, which showed a marked inhibitory activity against L5178Y mouse leukemic cell in vitro. The cytotoxicity of TS-1 on this cell was very strong and its ID50 was 0.018 micrograms/ml. Through direct comparison of its spectral data with those of an authentic sample, TS-1 was identified as the antifungal antibiotic, kalafungin, already isolated from the culture broth of Streptomyces tanashiensis. However, the isolation of kalafungin from an alkalophilic actinomycete and its cytotoxicity are reported for the first time in this paper. 相似文献
183.
184.
The dominant particle loss from an electron cyclotron resonance discharge plasma in a simple toroidal configuration is ascribed to the drift due to the vertical electric field produced by the electrons' toroidal drift. The electron density is increased by adding a small vertical field. This is explained by the electron flow along the line of force canceling the toroidal drift, resulting in reduction of the drift. 相似文献
185.
Pseudomorphic trench-type InGaAs/InAlAs quantum-wire field-effect transistors (QWR-FET) are realized by selective molecular beam epitaxy. The pseudomorphic QWR-FET has a negative differential resistance (NDR) effect with a low source–drain voltage (0.3 V). The NDR spectra are clearly observed in the 50–220 K temperature range. The operating current of the pseudomorphic QWR-FET is twice that of a lattice-matched QWR-FET, and this is thought to be due to the higher electron mobility. 相似文献
186.
Yoshihisa Kurasawa Sayuri Shimabukuro Yoshihisa Okamoto Kuniyoshi Ogura Atsushi Takada 《Journal of heterocyclic chemistry》1985,22(4):1135-1136
This paper describes an improved method for the synthesis of 3-(3-chloroquinoxalin-2-yl)-1,2-dihydro-1-formyl-2-oxo-3H-1,5-benzodiazepine (2) and its conversions into novel 3-substituted 1,5-benzodiazepine derivatives (3a,b and 4a,b). 相似文献
187.
Two new derivatives of glycosyl mitomycin C, 7-N-[4-O-(beta-D-glucopyranosyl and alpha-sialosyl)phenyl]-9a- methoxymitosanes, were synthesized, and their structures were elucidated by analysis of the nuclear magnetic resonance spectra. Field desorption mass spectrometry was successfully used for the confirmation of these structures. The cytotoxic, antibacterial, and antitumor activities of 7-N-(4-glycosylphenyl)-9a- methoxymitosanes were also examined. 相似文献
188.
Various Fe(II) complexes have been incorporated into Prussian blue (PB)|polyaniline (PAn)-modified electrodes, and their spectroelectrochemical properties been investigated using in situ and ex situ FTIR methods. It is shown that large anionic complexes once incorporated in the PAn matrix are not dedoped during the potential cycling and the charge balance is maintained by dedoping or incorporating electrolyte cations. This electrode system was applied to the electrocatalytic reduction of CO2 in aqueous solution, and the reduction products were identified by taking in situ FTIR spectra during the anodic stripping. At potentials higher than 0 V, the IR bands associated with the loss of carboxylic acid at 1362 cm−1 and the gain of CO2 at 2343 cm−1 were simultaneously observed, indicating that the CO2 was derived from the reoxidation of carboxylic acid. It is therefore confirmed that CO2 can be reduced to organic species including carboxylic acid on the PB|PAn-modified electrode with anionic Fe(II) complexes in aqueous solution, with an indication that the existence of the anionic metal complex is essential to such mediated reduction of CO2. 相似文献
189.
Hirohara S Obata M Saito A Ogata S Ohtsuki C Higashida S Ogura S Okura I Sugai Y Mikata Y Tanihara M Yano S 《Photochemistry and photobiology》2004,80(2):301-308
Thirty-two glycoconjugated porphyrins were synthesized by a modification of Lindsey method in the presence of Zn(OAc)(2).2H(2)O as a template. The Zn(2+) ion template strategy improved the yield about three-fold in the case of meta-substituted tetraphenylporphyrins. In addition, free-base porphyrins were obtained almost quantitatively by demetalation with 4 M HCl. Sixteen deacetylated glycoconjugated porphyrins were tested as candidate photodynamic therapy (PDT) drugs using HeLa cells. Most of the deacetylated glycoconjugated porphyrins showed higher cellular uptake than tetraphenylporphyrin tetrasulfonic acid (TPPS), and 5,10,15,20-tetrakis[4-(beta-D-arabinopyranosyloxy)phenyl]porphyrin (p-5d) in particular showed 18.5-fold higher uptake than TPPS. The photocytotoxicity of 5,10,15,20-tetrakis[4-(beta-D-glucopyranosyloxy)phenyl]porphyrin (p-5a), p-5d and TPPS was examined with HeLa cells, using a light dose of 16 J/cm(2). These photosensitizers had no cytotoxicity in the dark, but their photocytotoxicity increased in the order of TPPS < p-5a < p-5d. These results suggest p-5d is a good candidate for a PDT drug. 相似文献
190.
Yoshihisa Kurasawa Yoshihisa Okamoto Kuniyoshi Ogura Atsushi Takada 《Journal of heterocyclic chemistry》1985,22(3):661-664
Novel 3-quinoxalinyl-1,5-benzodiazepines 4, 5, 6, 9, 10 were synthesized via the ring transformation of 3-(N,N-dimethylcarbamoyl)furo[2,3-b]quinoxaline hydrochloride ( 1 ). The 3-quinoxalinyl- 1 ,5-benzodiazepine hydrochlorides 4 and 6 are the tautomers of the N1′-H (or N5-H) form and the C3-H form, respectively, which are stable in solid and solution. However, 4 (NH form) was found to be converted into 6 (C3-H form) by refluxing in acetic acid. The individual spectral evidences and different reactivity of these tautomers are described. 相似文献