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41.
The composition of nickel hexacyanoferrate(II) complexes depends on the ratios of sodium hexacyanoferrate(II) and nickel nitrate solutions mixed. The adsorption behavior of nickel hexacyanoferrate(II) is described; acid treatment of Ni2Fe(CN)6 accelerates the adsorption rate of cesium, but does not increase the adsorption capacity. The Ni—Cs exchange ratios of Ni2Fe(CN)6 are discussed. In concentrated salt solutions, the distribution coefficients of 59Fe, 60Co, 65Zn. 137Cs, 95Zr and 144Ce are determined together with those of 85Sr and 106Ru. A simple determination of 137Cs in sea water containing 59Fe, 60Co, 65Zn, 95Zr, 144Ce, 85Sr and 106Ru is described. 相似文献
42.
43.
Sadao Takagi Mune Maeda 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):775-780
The enthalpies of transfer of cyclohexanol from aqueous to aqueous - or -cyclodextrin solutions have been measured at various mole fractions at 298.15 K on a rocking twin-microcalorimeter of heat-conduction type and the molar enthalpies, Gibbs energies, and entropies of inclusion in the aqueous solutions have been determined by the method proposed by the authors [Netsu Sokutei
10, 103 (1983)], to elucidate the driving force of the molecular inclusion. Discussions are given for all the systems obtained by the authors, concluding that the driving force is the enhancement of the entropy.Calorimetric studies on molecular inclusion V. 相似文献
44.
Takeshi Matsumoto Akitami Ichihara Mitsutoshi Yanagiya Tamio Yuzawa Akiyoshi Sannai Hideaki Oikawa Sadao Sakamura Conrad Hans Eugster 《Helvetica chimica acta》1985,68(8):2324-2331
By a simple process, 3-methoxyjuglone (= 8-hydroxy-2-methoxy-1,4-naphthoquinone; 9 ) has been synthesized from 1,2,4-trimethoxybenzene ( 5 ) and converted, after prenylation, to α-caryopterone ( 1 ; Scheme 1), a pyranojuglone pigment from Caryopteris clandonensis. On the other hand, juglone (= 5-hydroxy-1,4-naphthoquinone; 12 ) was regioselectively prenylated at C(2) via its 1-methoxy-cyclohexa-1,3-diene adduct 15 (Scheme 2). The 2-prenyljuglone ( 4 ) thus formed led to 1 after oxidation and other reactions. 相似文献
45.
Fujio Okino Yukio Kawaguchi Kunitake Momota Toshihiro Ando Mamoru Yoshimoto 《Journal of fluorine chemistry》2004,125(11):1715-1722
Boron-doped semiconducting diamond films were prepared using BF3 by microwave plasma assisted chemical vapor deposition. B-doping was confirmed by SIMS and Raman spectroscopic measurements and the B-doping levels were estimated. Electrochemical behaviors of boron-doped diamond thin-film electrodes prepared using B2H6 and BF3 were studied by measuring cyclic voltammograms for anodic oxidation of 1,4-difluorobenzene in the liquid electrolyte, neat Et4NF·4HF. The results of the direct thermal interaction of elemental fluorine with hydrogenated and oxidized diamond surfaces are also presented. 相似文献
46.
Hiroyuki Kojima Toshio Fukumi Sadao Nakajima Yoshio Maruyama Kyoko Kosasa 《Chemical physics letters》1983,95(6):614-617
An elimination method is presented for laser isotope separation. It consists of flow cycles of feed molecules, in which an isotope component of non-interest, instead of the one of interest, is photolyzed to be eliminated, and the residue is recycled for photlysis. An isotope can be enriched as much as desired even if the isotope selectivity in the photolysis is low. The separation of 13C is demonstrated by employing multiphoton dissociation using a TEA CO2 laser. 相似文献
47.
48.
Takaguchi Y Tajima T Yanagimoto Y Tsuboi S Ohta K Motoyoshiya J Aoyama H 《Organic letters》2003,5(10):1677-1679
[reaction: see text] Thermotropic liquid crystallinity can be induced for an anthracene having a dendritic substituent. The photodimerization reaction of an anthracene moiety in the smectic phase proceeded quantitatively and regioselectively. 相似文献
49.
Synthesis and properties of optically active 1,3-diols and their derivatives as chiral dopants for ferroelectric liquid crystals 总被引:1,自引:0,他引:1
Tetsuo Kusumoto Ken-Ichi Sato Kumiko Ogino Tamejiro Hiyama Sadao Takehara Masashi Osawa Kayoko Nakamura 《Liquid crystals》1993,14(3):727-732
New chiral dopants β-hydroxy ketones 1, 1,3-diols 2, 1,3-dioxanes 3 and 1,3-dioxan-2-ones 4 were designed and synthesized. Reaction of (R)-1,2-epoxyoctane with carbanions derived from 2-(4-substituted phenyl)-1,3-dithianes followed by hydrolysis of the resulting hydroxy dithianes afforded 1. Reduction of 1 gave the diols 2, which yielded 3 upon acetalization and 4 upon carbonation. The syn isomers of 2, 3, and 4 exhibited larger spontaneous polarizations, when applied as chiral dopants, than the anti isomers or hydroxy ketones 1. 相似文献
50.
From 5-acetyl-4-hydroxy-6-methyl-α-pyrone, two phytotoxins, pyrenocine A and B, were synthesized and erroneous β-pyrone structure of the starting compound was corrected on the basis of spectroscopic data. 相似文献