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91.
Two new tetranor-cycloartane glycosides (1, 2) were isolated from Cimicifuga Rhizome. Their structures were determined by spectroscopic analysis. These compounds suggested the existence of a biogenetic pathway into C-23 lactone-type cycloartane glycosides. 相似文献
92.
A novel dicyanoheptafulvene 9 annulated by two spiro[4,5]deca-1,3-dienes was synthesized by the reaction of dispirocyclopentaazulenium cation 8 with bromomalononitrile. Although 9 was found to have a nonplanar heptafulvene structure by its X-ray crystallographic analysis, it is still capable of π-conjugation and thus shows appreciable contribution of the dipolar resonance form 9B based on its spectroscopic data. The degree of the contribution was further evaluated for various dicyanoheptafulvenes in terms of the partial sum of atomic charges of the dicyanomethylene group in the calculated structures besides the interplanar angles of the heptafulvene part and the length of the exocyclic double bond in the crystal structures. 相似文献
93.
Katsuya Sako Toshiaki Kakehi Shota Nakano Hiroyuki Oku Xu Feng Shen Tetsuo Iwanaga Manami Yoshikawa Kouta Sugahara Shinji Toyota Hiroyuki Takemura Teruo Shinmyozu Michito Shiotsuka Hitoshi Tatemitsu 《Tetrahedron letters》2014
Two novel redox-active 1,3-dithiole (DT) ring-fused 4,5-diazafluorene ligands with crown ether moieties (L1 and L2) were synthesized and characterized. The crystal structure of L1 was studied. The electrochemical and spectroscopic properties of these new ligands, as well as the corresponding bis(bipyridine)ruthenium(II) complexes [4: Ru L1(bpy)2 and 5: Ru L2(bpy)2], were also been investigated. 相似文献
94.
Purpose
To examine the effect of visual target blurring on accommodation.Methods
We evaluated the objective refraction values when the visual target (asterisk; 8°) was changed from the state without Gaussian blur (15 s) to the state with Gaussian blur adapted [0(without blur)?→?10, 0?→?50, 0?→?100: 15 s each].Results
In Gaussian blur 10, when blurring of the target occurred, refraction value did not change significantly. In Gaussian blur 50 and 100, when blurring of the target occurred, the refraction value became significantly myopic.Conclusion
Blurring of the distant visual target results in intervention of accommodation.95.
Atsushi KUMANOGOH Hitoshi KIKUTANI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(6):611-620
Semaphorins were originally identified as axon guidance cues involved in the development of the nervous system. In recent years, it is emerging that they also participate in various biological systems, including physiological and pathological processes. In this review, we primarily focus on our cumulative findings for the role of semaphorins and their receptors in the regulation of the immune system, while also summarizing recent progress in the context of cardiovascular system. 相似文献
96.
Mitiko Miura Hitoshi Arimori Hiromu Murata Akiko Kida Kazuaki Iishi 《Journal of Physics and Chemistry of Solids》1983,44(7):627-631
The effect of the electronic extension on the electrostatic potential was first taken into account functionally by Birman. We have applied his model to the lattice dynamics of CaO, where the degree of the electronic extension w was defined and determined with the use of the electronic charge density distribution obtained from analysis of X-ray data. Our treatment shown here not only gives a physically meaningful model including the feature of the electronic extension, but also involves essentially the same very simple process as the conventional point-charge model but with fewer adjustable parameters. Good reproduction of calculated phonon dispersion curves was obtained by taking into account the electronic extension, although the degree of the electronic extension, w, used to fit the curve was a little larger than that derived from the observed data owing to the first rough approximation for the potential energy arising from the electronic extension. 相似文献
97.
Hitoshi Tanaka Takayuki Otsu 《Journal of polymer science. Part A, Polymer chemistry》1977,15(11):2613-2621
Photodegradation behavior of atactic and isotactic polymers of tert-butyl vinyl ketone (t-BVK) and its copolymers with styrene and α-methylstyrene was studied in dioxane as a solvent at room temperature. The quantum yield of main-chain scission of atactic poly(t-BVK) was found to be larger than that of isotactic poly(t-BVK) and atactic poly(methyl vinyl ketone). From the Stern-Volmer plots on the quenching study of atactic poly(t-BVK) with naphthalene and 2,5-dimethyl-2,4-hexadiene, it was found that 60–70% of its photochemical reaction underwent main-chain scission from the triplet state. It was also found that the increase in t-BVK contents of both copolymers accelerated the photodegradation, and the copolymer with styrene was more photodegradable than that with α-methylstyrene. These results seemed to suggest that the main-chain scission of these vinyl ketone polymers and copolymers proceeded through a Norrish type II photoelimination mechanism. 相似文献
98.
Matthew R. Buckley Seong Youl Choi Kentarou Mawatari Hitoshi Murayama 《Physics letters. [Part B]》2009
Determining the spin of new particles is critical in identifying the true theory among various extensions of the Standard Model at the next generation of colliders. Quantum interference between different helicity amplitudes was shown to be effective when the final state is fully reconstructible. However, many interesting new physics processes allow only for partial reconstruction. In this Letter, we show how the interference effect can be unambiguously extracted even in processes that have two-fold ambiguity, by considering the correlation between two decay planes in e+e− collisions. 相似文献
99.
Michio Jimbo Hitoshi Konno Satoru Odake Yaroslav Pugai Jun'ichi Shiraishi 《Journal of statistical physics》2001,102(3-4):883-921
The Wakimoto construction for the quantum affine algebra U $_q$ ( $(\widehat{\mathfrak{s}\mathfrak{l}_2 })$ ) admits a reduction to the q-deformed parafermion algebras. We interpret the latter theory as a free field realization of the Andrews–Baxter–Forrester models in regime II. We give multi-particle form factors of some local operators on the lattice and compute their scaling limit, where the models are described by a massive field theory with $\mathbb{Z}$ $_k$ symmetric minimal scattering matrices. 相似文献
100.
Moyoko Tomiyasu Noriko Aida Yoshihiro Watanabe Kana Mori Kazuo Endo Kouki Kusakiri Jeff Kershaw Takayuki Obata Hitoshi Osaka 《Magnetic resonance imaging》2012