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51.
Melting characteristics of phase change material by natural convection heat transfer inside horizontal rectangular capsules are examined experimentally. The capsules are heated isothermally and three kinds of aspect ratios (qH/W=3, 1 and 1/3) are provided. Octadecane and ice are used, respectively, as the phase change material. A method of analysis applying the empirical correlations for natural convection heat transfer in a vertical or horizontal enclosure to the melting in the rectangular capsules is presented. The predicted results show good agreement with the experimental data. For the melting of octadecane and ice, it is found that the effect of aspect ratio on the melting process is not significant for the range ofB=1/3 to 3. 相似文献
52.
Watanuki S Matsuura K Tomura Y Okada M Okazaki T Ohta M Tsukamoto S 《Chemical & pharmaceutical bulletin》2011,59(11):1376-1385
We synthesized and evaluated inhibitory activity against T-type Ca(2+) channels for a series of 1-alkyl-N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]piperidine-4-carboxamide derivatives. Structure-activity relationship studies have revealed that the isopropyl substituent at the benzylic position plays an important role in exerting potent inhibitory activity, and the absolute configuration of the benzylic position was found to be opposite that of mibefradil, which was first launched as a new class of T-type Ca(2+) channel blocker. Oral administration of N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]-1-[2-(3-methoxyphenyl)ethyl]piperidine-4-carboxamide (17f) lowered blood pressure in spontaneously hypertensive rats without inducing reflex tachycardia, an adverse effect often caused by traditional L-type Ca(2+) channel blockers. 相似文献
53.
Ueda M Makino A Imai T Sugiyama J Kimura S 《Chemical communications (Cambridge, England)》2011,47(11):3204-3206
Two types of peptide nanotubes, one is prepared from an amphiphilic peptide having a right-handed helix segment and the other from that having a left-handed helix segment, are shown to transform the morphology into a vesicle by membrane fusion due to stereo-complex formation between these helical segments. 相似文献
54.
Ground state conformation for all possible geometrical isomers of hedycaryol was estimated by the molecular mechanics calculations. All isomers are indicated to exist in more than two conformations and the parallel conformation (TC or TT) is most stable for all isomers. 相似文献
55.
Reduction of dislocation density and improvement of optical quality in ZnO layers by MgO-buffer annealing 总被引:1,自引:0,他引:1
Hiroki Goto Hisao Makino Agus Setiawan Takuma Suzuki Chihiro Harada Tsutomu Minegishi Meoung-Whan Cho Takafumi Yao 《Current Applied Physics》2004,4(6):637-639
Optical properties of ZnO thin films with/without MgO-buffer annealing were investigated by low and room temperature photoluminescence measurements. The ZnO films were grown on c-sapphire substrates by plasma-assisted molecular-beam epitaxy employing a thin MgO-buffer layer. Dislocation density of ZnO layer was reduced from 5.3 × 109 to 1.9 × 109 cm−2 by annealing MgO-buffer prior to the growth of ZnO. The intensity of free exciton emission from the sample with MgO-buffer annealing was almost twice of that from the sample without annealing, while the deep level emission from the sample with MgO-buffer annealing was about 1/3 of that without annealing. The MgO-buffer annealing improves optical quality of overgrown ZnO films. 相似文献
56.
Hideaki Hioki Mizuki Fukutaka Miwa Kubo Mitsuaki Kodama Keiko Ideta 《Tetrahedron》2005,61(45):10643-10651
A new traceless linker was developed to synthesize a library of 42 compounds possessing an azomethine linkage using combinatorial solid-phase parallel synthesis. The loading of the substrates on a solid support and cleavage from the solid support were performed by an imine synthesis and by imine-exchanged process under mild conditions, respectively. Thioesters with a hydroxy group on the central core exhibited liquid crystalline properties with the widest transition temperatures in the library. 相似文献
57.
To develop a novel nucleoside analogue for the effective recognition of CG interruption in a homopurine-homopyrimidine tract of double-stranded DNA (dsDNA), we succeeded in the synthesis of a triplex-forming oligonucleotide (TFO) containing a novel 2′,4′-BNA (QB) bearing 1-isoquinolone as a nucleobase, and the triplex-forming ability and sequence-selectivity of the TFO (TFO-QB) were examined. On melting temperature (Tm) measurements, it was found that the TFO-QB formed a stable triplex DNA in a highly sequence-selective manner under near physiological conditions. 相似文献
58.
G.A. Anzelon I. Šlaus S.Y. Tin W.T.H. Van Oers R.M. Eisberg M. Makino C.N. Waddell M.B. Epstein 《Nuclear Physics A》1975,255(2):250-266
Proton-α bremsstrahlung cross sections have been measured at 45 MeV for θp = 91°, θα = 30° and θp = 70°, θα = 39°; at 40 MeV for θp = 92°, θα = 29°; and at 22 MeV for θp = 70°, θα = 30°. Calculations for these cross sections have been made using the Feshbach-Yennie model following the methods of Green and Prodon including p-α partial waves up to L = 4. These potential-independent calculations have only the proton-α elastic-scattering phase shifts as input. Good agreement with the experimental cross sectios has been obtained. 相似文献
59.
Tadahiro Kato Yoshihiro Yamaguchi Nobunori Abe Tadao Uyehara Tsuneo Namai Mitsuaki Kodama Yoshinori Shiobara 《Tetrahedron letters》1985,26(19):2357-2360
Structural elucidation including the absolute configuration was carried out on the trihydroxy C18 -fatty acids isolated from rice plant, Sasanishiki suffered from rice blast disease. 相似文献
60.
Hiroo Wada Keisuke Makino Tamio Takeuchi Hiroyuki Hatano Kohji Noguchi 《Journal of chromatography. A》1985,320(2)
The chromatographic behaviour in aqueous solution of pullulans, polyethylene glycols, peptides and proteins with different molecular weights on newly developed polyvinyl alcohol columns (Asahipak GS column series: GS-310, GS-320, GS-510 and GS-520) has been investigated. Pullulans and polyethylene glycols eluted according to the gel filtration mode, so both series of compounds produced almost equal calibration curves for GS-310 and GS-320 and for GS-510 and GS-520; the exclusion limits on GS-310 and GS-320 and on GS-510 and GS-520 were found to be ca. 40,000 and 300,000, respectively. Peptides and proteins were found to adsorb slightly on the columns. However, the plots of the elution volumes against the logarithm of the molecular weights for many of the substrates tested gave rise to the linear calibration curves. Recovery of several crude proteins was also studied for the columns and high values were obtained (81–100%). The effects of changes in the flow-rate, temperature and concentration of electrolytes added to the eluents, on the retention of all four types of compound are also reported. 相似文献