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131.
The photochemical behavior of N-acyliminoisoquinolinium and -quinolinium betaines has been investigated. In contrast to pyridinium betaines, the principal course of reaction is the 1,2-migration of N-acylamino groups. Substituent effects as well as solvent effects are observed. The results are rationalized in terms of diaziridine intermediates. 相似文献
132.
133.
134.
Satoshi Ikeda 《International Journal of Theoretical Physics》1974,11(3):205-212
In this paper, a non-local field (i.e. the (x, ψ)-field) is constructed by regarding the spinor (ψ) as the internal freedom attached to each point (x). Since this field is likened to a unified field between the (x)- and (ψ)-fields, the metric is given bydσψ=gλ dx λψ. Concerning this, some conformally equivalent relations are considered. Next, Weyl's gauge field is introduced into the concept of connection in order to consider the gauge invariance. Finally, some essential features underlying our non-local field are grasped by formulating some fundamental equations of the spin curvature tensors. 相似文献
135.
Yasumitsu Tamura Yasuyoshi Miki Jun-Ichi Minamikawa Masazunu Ikeda 《Journal of heterocyclic chemistry》1974,11(5):675-679
The mono-N-amino salts of 3-phenylcinnoline, phthalazine, 1-phenylphthalazine, 4-phenylquinazoline, 2-phenylquinoxaline, 1,5- and 1,8-naphthyridines are in high yields prepared by direct N-amination of the parent heterocycles with O-mesitylenesulfonylhydroxylamine. With the one expection of 3-phenylcinnoline, the site of N-amination was determined by mass and nmr spectral techniques. The results indicate that the N-amination occurs preferentially at the least sterically hindered nitrogen atom. 相似文献
136.
Tsukasa Ikeda Ryoichi Kojin Chul-joong Yoon Hiroshi Ikeda Masao Iijima Kenjiro Hattori Fujio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):669-674
Cyclodextrin (CD) has a hydrophobic cavity which acts like a binding site of an actual enzyme. But enzymatic turnover reaction did not occur in CD-catalyzed reactions. -CD was modified by a histamine group to attach a reactive functional group. -CD-histamine accelerates the hydrolysis of p-nitrophenyl acetate. Catalytic rate constant of this reaction is close to an actual enzyme, -chymotrypsin. Enzymatic turnover reaction is realized with this compound at around neutral pH value. 相似文献
137.
In order to know if it is possible to objectively decide the extent of infiltration of female genital malignant tumors into parametrium by using 111In-bleomycin scintigraphy, a fundamental and clinical investigation was made. The result was as follows; 1) The radiochemical purity and stability of 111In-BLM were comparatively unchangeable. When this complex was kept at room temperature for a week, there was not more than 2% of the free 111In. 2) As to blood clearance, when the blood radioactivity of 111In-BLM 5 minutes after the injection was counted as 100%, about 80% of the radioactivity was cleared from the blood in 48 hours. Over 50% of the radioactivity was excreted into the urine in 48 hours. 3) Of 29 cases of female genital malignant tumors, 23 cases (79%) showed positive images. Therefore 111In-BLM was found to be one of the suitable radiopharmaceuticals for the diagnosis of female genital malignant tumors. 4) 111In-BLM scintigraphy was of great use for deciding the extent of the invasion of carcinoma cervicis uteri into parametrium and for the search of metastasis. 相似文献
138.
Yellow and colourless complexes of molybdophosphate were investigated by the use of laser Raman spectroscopy. Two kinds of yellow molybdophosphates were identified in the weakly acidic solutions: 12-molybdophosphoric and 11-molybdophosphoric acid which are in equilibrium in solution at pH 1-2. When excess phosphate is present, the colourless molybdophosphate is formed. This complex exists in the solutions of pH 4-1 under the condition of excess phosphate ([P]/[Mo] > 2). This complex was confirmed to be P2Mo5O6?23 and is so stable that the yellow molybdophosphate is converted into the colourless by excess phosphate. 相似文献
139.
N-Phenethylhexadecanamide was isolated from the MeOH extract of the fruiting bodies of the mushroom Laetiporus sulphureus together with eburicoic acid. Their structures were elucidated by spectroscopic methods. 相似文献
140.
Aliu E Andringa S Aoki S Argyriades J Asakura K Ashie R Berns H Bhang H Blondel A Borghi S Bouchez J Burguet-Castell J Casper D Cavata C Cervera A Cho KO Choi JH Dore U Espinal X Fechner M Fernandez E Fukuda Y Gomez-Cadenas J Gran R Hara T Hasegawa M Hasegawa T Hayashi K Hayato Y Helmer RL Hill J Hiraide K Hosaka J Ichikawa AK Iinuma M Ikeda A Inagaki T Ishida T Ishihara K Ishii T Ishitsuka M Itow Y Iwashita T Jang HI Jeon EJ Jeong IS Joo K Jover G Jung CK Kajita T Kameda J Kaneyuki K Kato I 《Physical review letters》2005,94(8):081802
We present results for nu(mu) oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced nu(mu) beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy-dependent disappearance of nu(mu), which we presume have oscillated to nu(tau). The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma). 相似文献