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1.
Inside Cover: Photoinduced Formation of an Azobenzene‐Based CD‐Active Supramolecular Cyclic Dimer (Chem. Eur. J. 18/2015) 下载免费PDF全文
2.
Within the large literature on inter-organizational networks, there has been some discussion of linking-pin organizations and the role they play in integrating these networks. Based on this verbal specification of linking-pin organizations, we construct operational criteria and empirical methods for identifying these structurally important organizations in potentially large and complex inter-organizational networks. These methods are based on ideas drawn from blockmodeling, structural holes, centrality and centralization of networks, and identifying cut-points in networks. These methods are applied to a constructed example and then to real empirical inter-organizational networks. Implications and contrasts with other methods are discussed, together with some open problems. 相似文献
3.
H. -L. Li Y. Ujihira S. Tanaka T. Yamashita K. Horie 《Journal of Radioanalytical and Nuclear Chemistry》1996,210(2):543-553
Positron annihilation lifetime measurements of PMMA, PEMA, PiPMA, PnPMA and PnBMA were performed in the temperature range between 15 and 300 K, where , and relaxational transitions occur for these polyalkylmethacrylates. The variations of free volume size and content calculated from the longest lifetime component against temperature are correlated to the results obtained by dielectric, viscoelastic and dynamic mechanical relaxation data of the polymers. The variations of free volume sizes and contents, apparent free volume fraction and size distribution of the polyalkylmethacrylates are well correlated with the rotational transitions of side chains. The location of free volumes, in which positronium annihilates can be estimated near the vicinity of alkyl groups bound to oxygen atom of side ester chains. 相似文献
4.
Antiviral activity of natural occurring flavonoids in vitro 总被引:2,自引:0,他引:2
Y Tsuchiya M Shimizu Y Hiyama K Itoh Y Hashimoto M Nakayama T Horie N Morita 《Chemical & pharmaceutical bulletin》1985,33(9):3881-3886
5.
Analysis of tea components by high-performance liquid chromatography and high-performance capillary electrophoresis 总被引:3,自引:0,他引:3
Tea is one of the most popular beverages in the world. The number of reports on the analysis of tea components, especially for catechins, has recently been increasing. We review the recent reports on the analysis of tea components using the analytical methods of high-performance liquid chromatography and high-performance capillary electrophoresis. 相似文献
6.
M Horie K Saito Y Hoshino N Nose N Hamada H Nakazawa 《Journal of chromatography. A》1990,502(2):371-378
A simple and selective method for the determination of sulphamethazine (SMT) and its metabolite, N4-acetylsulphamethazine (N4-AcSMT), in meat by high-performance liquid chromatography (HPLC) with photodiode-array detection was developed. The drugs were extracted from meat with 0.2% metaphosphoric acid-methanol (6:4), followed by a Bond-Elut C18 clean-up procedure. The HPLC separation was carried out on a Supersphere RP-18e column (125 X 4.0 mm I.D.) using 0.05 M sodium dihydrogenphosphate (pH 4.5)-acetonitrile (8:2) as the mobile phase at a flow-rate of 0.5 ml/min, and monitored with a photodiode-array detector. The recoveries of SMT and N4-AcSMT from meat fortified at 0.5 micrograms/g were 90.1-93.3 and 93.0-94.4%, respectively, with coefficients of variation of 1.9-3.2 and 1.5-2.7%. The limits of detection were 0.02 micrograms/g for each drug. SMT was found in ten samples of imported meat (12.5%) at levels ranging from 0.05 to 1.05 micrograms/g. 相似文献
7.
M Shimizu S Horie S Terashima H Ueno T Hayashi M Arisawa S Suzuki M Yoshizaki N Morita 《Chemical & pharmaceutical bulletin》1989,37(9):2531-2532
Aldose reductase (AR) inhibitory activity-directed fractionation of the 70% ethanolic extract of Para-parai mí, Phyllanthus niruri, has led to the isolation of three active components, ellagic acid (1), brevifolin carboxylic acid (4) and ethyl brevifolin carboxylate (5). Among them, 1 showed the highest inhibitory activity, being about 6 times more potent than quercitrin, which is a known natural inhibitor of AR. 相似文献
8.
Secondary propene ozonide and isobutene ozonide were formed in the gas-phase ozonolysis of ethene with added acetaldehyde and acetone, respectively. Combined with the formation of hydroperoxymethyl formate and methoxymethyl hydroperoxide in the ethene-ozone reaction system in the presence of HCOOH and CH3OH, respectively, formation of the secondary ozonides reveals a close similarity between the gas-phase and the liquid-phase ozonolysis of alkenes. 相似文献
9.
10.
Yamamoto Y Yamamoto A Furuta SY Horie M Kodama M Sato W Akiba KY Tsuzuki S Uchimaru T Hashizume D Iwasaki F 《Journal of the American Chemical Society》2005,127(42):14540-14541
The oxidized octaethyltetraphenylporphyrin (1, OETPP) and the corresponding newly prepared octaisobutyltetraphenylporphyrin (3, OisoBuTPP) could be isolated from the reaction of OETPPLi2 (or OisoBuTPPLi2) with SOCl2. The X-ray analysis and the characteristic UV-vis spectra of 1 and 3 revealed that these are the first examples of 16 pi nonaromatic porphyrins. 相似文献