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151.
The second-harmonic generation of a cyanine dye in an LB film was investigated by varying the incident angle of the excitation laser. There was a clear dependence on the incident angle, which was simulated by a simple model. Thus, a highly sensitive determination should be carried out at such an angle where the efficiency of the second-harmonic generation shows its maximum. 相似文献
152.
The main absorption site of ethyl 2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionate (AL-294) in rats was the upper portion of the small intestine. Both AL-294 and AL-294 acid (2-chloro-3-[4-(2-methyl-2-phenylpropyloxy)phenyl]propionic acid), a hydrolyzed form of AL-294, were absorbed in a smaller quantity under the bile fistula condition (pancreatic juice and bile were excluded). Compared with the absorption of AL-294 as an emulsion under the sham operation condition, the absorption of AL-294 as the emulsion decreased under the condition where only pancreatic juice was excluded. The bioavailability under this condition was very similar to that under the bile fistula condition, whereas the absorption of AL-294 acid did not decrease when the pancreatic juice was excluded. From these results, the absorption mechanism of AL-294 is considered as follows: AL-294 was hydrolyzed to AL-294 acid by lipase in pancreatic juice, then AL-294 acid was solubilized with bile salts to form mixed micelles in the intestinal lumen. AL-294 acid from this form was easily absorbed into the systemic circulation. Absorption of AL-294 increased when the particle size of the emulsion was smaller. The reason was assumed to be that the smaller particle size offered the greater oil-water interface for lipase activity against AL-294. 相似文献
153.
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155.
Kenjiro Ogawa 《Discrete Mathematics》2009,309(22):6353-6358
For a poset P=(X,≤P), the double bound graph (DB-graph) of P is the graph DB(P)=(X,EDB(P)), where xy∈EDB(P) if and only if x≠y and there exist n,m∈X such that n≤Px,y≤Pm. We obtain that for a subposet Q of a poset P,Q is an (n, m)-subposet of P if and only if DB(Q) is an induced subgraph DB(P). Using this result, we show some characterizations of split double bound graphs, threshold double bound graphs and difference double bound graphs in terms of (n, m)-subposets and double canonical posets. 相似文献
156.
Takuya Ogawa Jun Watanabe Yoshito Oshima 《Journal of polymer science. Part A, Polymer chemistry》2009,47(10):2656-2663
A catalyst‐free polysiloxane synthetic process that uses high temperature and pressure water for the hydrolysis and subsequent polycondensation of phenyltrimethoxysilane was studied in detail to gain insights into the reaction mechanism. It was suggested that this process is essentially composed of two stages: (1) oligomerization of phenyltrimethoxysilane yielding low‐molecular weight species with high contents of silanol and methoxy groups and (2) polycondensation of the oligomers yielding high‐molecular weight species. The use of a preformed oligosiloxane as a starting material was informative to understand the polycondensation stage. A modified synthetic process in which a stop valve was introduced to control the internal pressure was developed based on the understanding of the present process. This modified process enabled a two‐stage reaction resulting in a discernible increase of the molecular weight of polysiloxane. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2656–2663, 2009 相似文献
157.
Ryu Sato Toshiyuki Fujio Shiduko Nakajo Satoshi Ogawa Ashraful Alam 《Tetrahedron letters》2007,48(17):3013-3016
The synthesis of benzopentathiepin having a hydroxyl group at the neighboring position of polysulfur ring was performed by demethylation of 6-ethyl-9-methoxybenzopentathiepin with hydrogenbromide. Benzotrithiole having hydroxyl group was not isolated at all. The hydroxyl group was also alkylated with alkyl iodide in the presence of weak base. 相似文献
158.
Yoshimasa Makita Tomofumi Danno Keisuke Ikeda Hsien-Han Lee Taro Abe Kento Sogawa Akihiro Nomoto Shin-ichi Fujiwara Akiya Ogawa 《Tetrahedron letters》2017,58(48):4507-4509
Hemicryptophanes are covalent molecular cages, constructed from a cyclotriveratrylene-based host unit and a functional unit linked by covalent spacers, which have been designed to accommodate endohedral functionalities in the cavity. In this study, the synthesis and characterization of the rigid, biphenyl-linked hemicryptophane 1 were investigated by NMR, ESI-MS, and X-ray crystallography. The structure of the inclusion complex, in which a dichloromethane molecule was constructed encapsulated within 1, was characterized by X-ray crystallography. An endohedral, cobalt(II) hemicryptophane complex 2 was also synthesized and characterized ESI-MS and X-ray crystallography. The X-ray crystal structure of 2 showed that the biphenyl-linked hemicryptophane had three components—a molecule each of chloroform and acetonitrile, and a cobalt(II) ion—within its cavity. 相似文献
159.
Upon visible-light irradiation, reductive carboxylation of alkyl halides takes place by using a SmI2/Sm mixed system under atmospheric CO2 to afford the corresponding carboxylic acids in good to excellent yields. 相似文献
160.
Vossen A Seidl R Adachi I Aihara H Aushev T Balagura V Bartel W Bischofberger M Bondar A Bračko M Browder TE Chang MC Chen A Chen P Cheon BG Cho K Choi Y Eidelman S Feindt M Gaur V Gabyshev N Garmash A Golob B Perdekamp MG Haba J Hayasaka K Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Joshi NJ Kichimi H Kim HO Kim MJ Ko BR Kumita T Lange JS Lee MJ Lee SH Leitgab M Li Y Liu C Liventsev D Louvot R McOnie S Miyata H Miyazaki Y Mizuk R Mohanty GB Nakano E 《Physical review letters》2011,107(7):072004
The interference fragmentation function translates the fragmentation of a quark with a transverse projection of the spin into an azimuthal asymmetry of two final-state hadrons. In e(+)e(-) annihilation the product of two interference fragmentation functions is measured. We report nonzero asymmetries for pairs of charge-ordered π(+)π(-) pairs, which indicate a significant interference fragmentation function in this channel. The results are obtained from a 672 fb(-1) data sample that contains 711 × 10(6) π(+)π(-) pairs and was collected at and near the Υ(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. 相似文献