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151.
152.
153.
Nobuaki Nakashima Noboru Mataga Chiyoe Yamanaka Riichiro Ide Soichi Misumi 《Chemical physics letters》1973,18(3):386-389
Laser action of the intramolecular exciplex emission of p-(9′-anthryl)-N,N-dimethylaniline (ADMA) has been found in non-polar and slightly polar solvents. In moderately as well as strongly polar solvents, the laser emission is quenched in spite of the fact that the spontaneous fluorescence yields is larger in polar than in non-polar solvents. 相似文献
154.
Haruhisa Shirahama Kiyoharu Hayano Yoshiro Kanemoto Shunjiro Misumi Toshikazu Ohtsuka Nobuhiro Hashiba Akio Furusaki Shizuaki Murata Ryoji Noyori Takeshi Matsumoto 《Tetrahedron letters》1980,21(50):4835-4838
Two cyclohumulanoids, dl-bicyclohumulenone () and dl-africanol ( were synthesized through newly developed conformationally selective transannular cyclization of humulene 9,10-epoxide (). The epoxide was converted to a bicyclohumulenediol diacetate in 70% yield by treatment with BF3·OEt2-Ac2O, while treatment of with trimethylsilyl trifluoromethansulfonate gave an africen-10-ol (a and b) in 80% yield. The two intermediates and furnished the natural products and in 30 and 8 % yield from respectively. 相似文献
155.
Toyoharu Hayashi Tatsuo Suzuki Noboru Mataga Yoshiteru Sakata Soichi Misumi 《Chemical physics letters》1976,38(3):599-601
Both 1,2-di(1-anthryl)ethane (I) and 1,2-di(9-anthryl) ethane (II) show two types of excimer fluorescence spectra under different conditions; one with peak at 460 nm (type-1) and the other with peak at 530 nm (type-2). Furthermore, the type-1 excimer emission shows a peculiar dependence upon the solvent polarity. 相似文献
156.
Miyake H Okada T Samjeské G Osawa M 《Physical chemistry chemical physics : PCCP》2008,10(25):3662-3669
A mechanistic study of electrocatalytic oxidation of formic acid on Pd in sulfuric and perchloric acids is reported. Surface-enhanced infrared absorption spectroscopy in the attenuated total reflection mode (ATR-SEIRAS) shows the adsorption of CO, bridge-bonded formate, bicarbonate, and supporting anions on the electrode surface. Poisoning of the Pd surface by CO, formed by dehydration of formic acid, is very slow and scarcely affects formic acid oxidation. The anions are adsorbed more strongly in the order of (bi)sulfate > bicarbonate > perchlorate, among which the most strongly adsorbed (bi)sulfate considerably suppresses formic acid oxidation in the double layer region. The oxidation is suppressed also at higher potentials in both acids by the oxidation of the Pd surface. Adsorbed formate is detected only when formic acid oxidation is suppressed. The results show that formate is a short-lived reactive intermediate in formic acid oxidation and is hence detected when its decomposition yielding CO(2) is suppressed. The high electrocatalytic activity of Pd can be ascribed to the high tolerance to CO contamination and also high catalytic activity toward formate decomposition. 相似文献
157.
Takeshi Ikeda Hiroshi Mizukawa Tatsuhiro Nakajima Hiro-Fumi Yamada 《Advances in Applied Mathematics》2008,40(4):514-535
Formulas are obtained that express the Schur S-functions indexed by Young diagrams of rectangular shape as linear combinations of “mixed” products of Schur's S- and Q-functions. The proof is achieved by using representations of the affine Lie algebra of type . A realization of the basic representation that is of “”-type plays the central role. 相似文献
158.
Hiroaki Takemoto Yuki Saito Kei Misumi Masaki Nagasaki Yoshinori Masuo 《Molecules (Basel, Switzerland)》2022,27(9)
(1) Sesame oil aroma has stress-relieving properties, but there is little information on its effective use and active ingredients. (2) Methods: ICR male mice were housed under water-immersion stress for 24 h. Then, the scent of sesame oil or a typical ingredient was inhaled to the stress groups for 30, 60, or 90 min. We investigated the effects of sesame oil aroma on mice behavior and the expression of the dual specificity phosphatase 1 (DUSP1) gene, a candidate stress marker gene in the brain. (3) Results: In an elevated plus-maze test, the rate of entering into the open arm of a maze and the staying time were increased to a maximum after 60 min of inhalation, but these effects decreased 90 min after inhalation. As for the single component, anxiolytic effects were observed in the 2,5-dimethylpyrazine and 2-methoxy phenol group, but the effect was weakened in the furfuryl mercaptan group. The expression levels of DUSP1 in the hippocampus and striatum were significantly decreased in 2,5-dimethylpyrazine and 2-methoxy phenol groups. (4) Conclusions: We clarified the active ingredients and optimal concentrations of sesame oil for its sedative effect. In particular, 2,5-dimethylpyrazine and 2-methoxy phenol significantly suppressed the stress-induced changes in the expression of DUSP1, which are strong anti-stress agents. Our results suggest that these molecules may be powerful anti-stress agents. 相似文献
159.
Dr. Tatsuhiro Uchikura Mari Oshima Minami Kawasaki Dr. Kohei Takahashi Prof. Nobuharu Iwasawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(19):7473-7478
Supramolecular photocatalysis via charge-transfer excitation of a host–guest complex was developed by use of the macrocyclic boronic ester [2+2]BTH-F containing highly electron-deficient difluorobenzothiadiazole moieties. In the presence of a catalytic amount of [2+2]BTH-F, the triplet excited state of anthracene was generated from the charge-transfer excited state of anthracene@[2+2]BTH-F by visible-light irradiation, and cycloaddition of the excited anthracene with several dienes and alkenes proceeded in a [4+2] manner in high yields. 相似文献
160.
Tatsuhiro Tsukamoto Guangbin Dong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15361-15365
A cobaloxime-catalyzed acceptorless dehydrogenative cyclization of o-teraryls was developed. In stark contrast to the established methods such as the Scholl or Mallory reactions, this method does not require any strong acids or oxidants, and shows high atom economy and a broad substrate scope. It operates at near room temperature with light as the source of energy. Acid- or oxidant-sensitive functional groups, such as 4-methoxyphenyl, unprotected benzyl alcohol, silyl ether, and thiophene groups are tolerated. Remarkably, aryls with electron-withdrawing groups, and electron-poor heteroarenes, such as pyridine and pyrimidine, can also react. Preliminary mechanistic study reveals that hydrogen gas is released during the reaction, and both light and the cobalt catalyst are important for the dehydrogenation step. 相似文献