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181.
182.
Abstract Experiments have been performed to provide basic heat transfer data for thermal convection in a horizontal concentric annulus partially filled with water. A real-time holographic interferometry was employed to map the temperature distribution and a laser shadowgraph system was used to measure local heat transfer coefficients along the heated inner cylinder. Experimental results demonstrate that a minimum average Nusselt number for the water-wetted portion of the inner cylinder occurs at the air-water interface situated flush with the top of the inner cylinder. Corresponding numerical simulations were conducted for the cases of either fully or half-filled with water and the predictions agree well with the experimental results. 相似文献
183.
Sho Itoh Hirofumi Hidai Hitoshi Tokura 《Applied Physics A: Materials Science & Processing》2013,112(4):1043-1049
The modification of transparent materials using a femtosecond laser has been studied. We previously proposed a new method of modifying glass using a continuous-wave laser, named continuous-wave laser backside irradiation (CW-LBI), in which CW laser illumination induces a change in the refractive index without cracking the glass. In this study, we investigated the process of glass modification by CW-LBI using time-lapsed imaging and by calculation of the temperature. First, the modification of glass was observed by the shadowgraph method, and it was found that thermal radiation was included in the phenomena that occurred when the glass was modified. Second, the time-lapsed temperature distribution was calculated. The temperature distribution was roughly in accordance with the shape of the modified area observed in the shadowgraphs. We concluded that the radius of the modified area is dependent on the temperature reached in the glass. 相似文献
184.
Real spherical designs and real and complex projective designs have been shown by Delsarte, Goethals, and Seidel to give rise to association schemes when the strength of the design is high compared to its degree as a code. In contrast, designs on the complex unit sphere remain relatively uninvestigated, despite their importance in numerous applications. In this paper, we develop the notion of a complex spherical design and show how many such designs carry the structure of an association scheme. In contrast with the real spherical designs and the real and complex projective designs, these association schemes are nonsymmetric. 相似文献
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187.
Kwok-Pun HO 《数学物理学报(B辑英文版)》2018,38(1):93-109
We introduce the martingale Morrey spaces built on Banach function spaces. We establish the Doob's inequality, the Burkholder-Gundy inequality and the boundedness of martingale transforms for our martingale Morrey spaces. We also introduce the martingale block spaces. By the Doob's inequality on martingale block spaces, we obtain the Davis' decompositions for martingale Morrey spaces. 相似文献
188.
Hiroshi Tanaka Prof. Dr. Sho Yamaguchi Atsushi Yoshizawa Dr. Motoki Takagi Dr. Kazuo Shin‐ya Dr. Takashi Takahashi Prof. Dr. 《化学:亚洲杂志》2010,5(6):1407-1424
In this report, we describe the stereoselective synthesis of a combinatorial library comprised of 16 deoxyhexasaccharides that are related to a landomycin A sugar moiety, based on an orthogonal deprotection strategy. The use of an olivosyl donor containing a benzyl ether at the C3 position and benzoyl ester at the C4 position, and the olivosyl donor, a naphthylmethyl ether, and a p‐nitrobenzylethyl or benzyl sulfonyl ester enabled the synthesis of a set of four diolivosyl units containing a hydroxyl group at the C3 or C4 position by a simple glycosylation and deprotection procedure. Using a phenylthio 2,3,6‐trideoxyglycoside, α‐selective glycosidation proceeded without anomerization of the 2,6‐dideoxy‐β‐glycosides. In addition, alkylhydroquinone and levulinoyl groups were found to be an effective set of orthogonal protecting groups for the anomeric position and a hydroxyl group. The coupling of all combinations of trisaccharide units in a β‐selective manner was accomplished by activation of the glycosyl imidate with I2 and Et3SiH. No cleavage of the acid‐labile 2,3,6‐trideoxyglycoside was observed under the conditions used for the reactions. Finally, all of the protected hexasaccharides were deprotected by hydrolysis of the esters, microwave (MW) assisted cleavage of the 2‐trimethylsilylethoxymethoxy (SEM) ether, and a Birch reduction. 相似文献
189.
Sho Hirai 《Tetrahedron letters》2010,51(38):5076-5079
This Letter describes an enantioselective approach to (−)-platencin. A uniquely functionalized chiral intermediate, which was prepared via the highly enantioselective catalytic asymmetric intramolecular cyclopropanation (CAIMCP) that we have developed, was successfully transformed to Nicolaou’s intermediate in his total synthesis of (−)-platencin. 相似文献
190.
Kitade M Tanaka H Oe S Iwashima M Iguchi K Takahashi T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(5):1368-1376
The solid-phase synthesis of a combinatorial cross-conjugated dienone library based on the structure of clavulones and their biological activity are reported. Clavulones are a family of marine prostanoids, and are composed of a cross-conjugated dienone system bearing two alkyl side-chains. The cross-conjugated dienone system irreversibly reacted with two nucleophiles. Our strategy for the solid-phase synthesis of the cross-conjugated dienones involves the Sonogashira-coupling reaction of a solid-supported cyclopentenone 10 bearing an acetylene group, followed by aldol condensation with aldehydes. The diphenyl derivative 7 aA was prepared from the solid-supported cyclopentenone 10 in 56% total yield. Combinatorial synthesis of a small library using twelve halides and eight aldehydes resulted in the production of 74 desired compounds from 98 candidates, and were detected by their mass spectra. Antiproliferative effects of the crude compounds against HeLaS3 cells showed that eleven samples showed strong antitumor activity (IC50<0.05 microM). Further biological examination of four purified compounds by using five tumor cell lines (A549, HeLaS3, MCF7, TMF1, and P388) revealed strong cytotoxicity comparable to that of adriamycin. 相似文献