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61.
We consider the scattering problem for the Hartree type equation in
n
withn2:
相似文献
62.
Nanosecond time-resolved UV/vis absorption spectroscopy on laser flash photolysis was conducted for photoinduced electron-transfer reactions of 7-benzhydrylidenenorbornene (1) and 7-benzhydrylidenenorbornane (5). The differences in the observed absorption bands and the structures of 1+ and 5+ were evaluated successfully using calculations based on (time dependent) density functional theory, confirming the nonclassical nature of 1+. 相似文献
63.
64.
Prof. Dr. Hayato Tsurugi Prof. Dr. Kazushi Mashima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(4):913-919
Herein, we provide a new protocol to reduce various transition-metal complexes by using organosilicon compounds in a salt-free fashion with the great advantage of generating pure low-valent metal species and metallic(0) nanoparticles, in sharp contrast to reductant-derived salt contaminants obtained by reduction with metal reductants. The organosilicon derivatives 1,4-bis(trimethylsilyl)-2,5-cyclohexadiene ( 1 a ), 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene ( 1 b ), 1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene ( 2 a ), 2,5-dimethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene ( 2 b ), 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene ( 2 c ), and 1,1′-bis(trimethylsilyl)-1H,1′H-4,4′-bipyridinylidene ( 3 ) all served as versatile reductants for early transition-metal complexes and produced only easy-to-remove organic compounds, such as trimethylsilylated compounds and the corresponding aromatics, for example, benzene, toluene, pyrazine, and 4,4′-bipyridyl, as the byproducts. The high solubility of the reductants in organic solvents enabled us to monitor the catalytic reactions directly and to detect any catalytically active species so that we could elucidate the reaction mechanism. 相似文献
65.
Takayoshi Tsuzuki Natsumi Sakaguchi Dr. Takashi Kudoh Satoshi Takano Masato Uehara Dr. Takashi Murayama Prof. Dr. Takashi Sakurai Dr. Minako Hashii Prof. Dr. Haruhiro Higashida Karin Weber Prof. Dr. Andreas H. Guse Dr. Tomoshi Kameda Dr. Takatsugu Hirokawa Dr. Yasuhiro Kumaki Prof. Dr. Barry V. L. Potter Dr. Hayato Fukuda Dr. Mitsuhiro Arisawa Prof. Dr. Satoshi Shuto 《Angewandte Chemie (International ed. in English)》2013,52(26):6633-6637
66.
67.
Hidefumi Yoshii Aya Sakane Daisuke Kawamura Tze Loon Neoh Hayato Kajiwara Takeshi Furuta 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):591-596
The release kinetics of (−)-menthol from chewing gum was investigated using various encapsulated powder of (−)-menthol. The
apparatus of flavor release of chewing gum was made with a glass container of mashing homogenizer. Flavor release behavior
could be correlated with Avrami’s equation. Chewing gum containing (−)-menthol/γ-CD complex powder had longer retention of
(−)-menthol compared with the β-CD complex powder and the (−)-menthol encapsulated in modified starches. The activation energies
of (−)-menthol release from chewing gum were 106 kJ/mol for γ-CD complex and 74 kJ/mol for (−)-menthol/β-CD complex powder
and emulsified (−)-menthol encapsulated in HI-CAP, respectively. 相似文献
68.
Kengo Oka Shunsuke Fuchi Dr. Keita Komine Dr. Hayato Fukuda Prof. Dr. Susumi Hatakeyama Prof. Dr. Jun Ishihara 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12862-12867
The catalytic asymmetric total synthesis of (−)-exiguolide, a complex 20-membered macrolide embedded with a bis(tetrahydropyran) motif, is reported. The convergent synthesis involves the construction of the C1–C11 tetrahydropyran segment via catalytic asymmetric allylation and Prins cyclization, and the formation of the C12–C21 phosphonate segment via catalytic asymmetric cyclocondensation reaction and Johnson–Claisen rearrangement. The synthesis of 15-epi-exiguolide is also described. 相似文献
69.
Kenta Rakumitsu Jukiya Sakamoto Prof. Dr. Hayato Ishikawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(38):8996-9000
The first enantioselective total syntheses of (−)-secologanin ( 1 ), (−)-5-carboxystrictosidine ( 2 ), and (−)-rubenine ( 3 ) were accomplished in 10, 9, and 14 steps, respectively. The key transformation in the synthesis of 1 was a sequential anti-selective organocatalytic Michael reaction/Fukuyama reduction/spontaneous cyclization to form an optically active dihydropyran ring. In addition, the secologanin tetraacetate ( 16 ), which is a potential key intermediate for the bioinspired divergent syntheses of monoterpenoid indole alkaloids, was prepared in gram-scale in seven steps. The total syntheses of 2 and 3 , which are classified as glycosylated monoterpenoid indole alkaloids, were achieved through bioinspired transformations such as a diastereoselective Pictet–Spengler reaction, a site- and stereoselective epoxidation, and a site-selective epoxide ring-opening followed by a lactonization reaction. 相似文献
70.
Masatoshi Ogawa Shoji Kamiya Hayato Izumi Yutaka Tokuda 《Physica B: Condensed Matter》2012,407(15):3034-3037
This paper focuses on the effects of temperature and environment on the electronic properties of dislocations in n-type single crystal silicon near the surface. Deep level transient spectroscopy (DLTS) analyses were carried out with Schottky electrodes and p+–n junctions. The trap level, originally found at EC−0.50 eV (as commonly reported), shifted to a shallower level at EC−0.23 eV after a heat treatment at 350 K in an inert environment. The same heat treatment in lab air, however, did not cause any shift. The trap level shifted by the heat treatment in an inert environment was found to revert back to the original level when the specimens were exposed to lab air again. Therefore, the intrinsic trap level is expected to occur at EC−0.23 eV and shift sensitively with gas adsorption in air. 相似文献
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