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51.
Takiue T Hirose D Murakami D Sakamoto H Matsubara H Aratono M 《The journal of physical chemistry. B》2005,109(34):16429-16434
The interfacial tension gamma of the hexane solution of 1H,1H-perfluorononanol (FDFC(9)OH) and its omega-hydrogenated analogue, 1H,1H,9H-perfluorononanol (HDFC(9)OH), against water was measured as a function of pressure and concentration at 298.15 K in order to clarify the effect of omega-dipole on the orientation of fluorononanol molecules from the viewpoint of volume. The adsorbed films of both alcohols exhibit two kinds of phase transitions among three different states: the gaseous, expanded, and condensed states. The partial molar volume changes of adsorption - in the expanded and condensed states were evaluated and compared between the two systems. The - values of both alcohols are negative, and thus the alcohol molecules have smaller volume in the adsorbed film than in the bulk solution. Furthermore, the value was obtained through the evaluation of by the density measurement of the bulk hexane solution. It was found that the value of HDFC(9)OH is smaller than that of FDFC(9)OH in the condensed state. On the basis of three matters concerning the molecular structure of alcohols, the occupied area at the interface, and the orientation of FDFC(9)OH in the adsorbed film deduced from the earlier results of X-ray reflectivity measurement, the mean tilt angle of HDFC(9)OH from the interface normal in the condensed film was estimated to be 15 degrees . The thermodynamic estimation demonstrated here is highly valuable one to provide structure information on an adsorbed film. 相似文献
52.
Kenichi Hashizume Hiroyasu Ogiwara Hiroshi Taniguchi 《International Journal of Multiphase Flow》1985,11(5):643-658
Two-phase flow in horizontal pipe was analyzed with simplified models for annular and stratified flow. The velocity profiles for the liquid and gas phase were described with the Prandtl mixing length. From this analysis, the frictional pressure drop was calculated with the modified Baker map for flow pattern transition. The intermediate region, i.e. wavy flow, was interpolated between annular and stratified flow. Comparison of this analysis with existing experimental data of refrigerants showed good agreement. 相似文献
53.
Yoshiharu Matsubara Toshikazu Uchida Takashi Ohnishi Koichi Kanehira Yoshiji Fujita Tsuneaki Hirashima Ikuzo Nishiguchi 《Tetrahedron letters》1985,26(37):4513-4516
Anodic oxidation in acetic acid of polycyclic cyclopropanes, namely tricyclene, cyclofenchene, and longicyclene, followed by hydrolysis brought about stereo- and regioselective formation of the corresponding homoallylic alcohols as the main product in good yields. 相似文献
54.
The energy transfer between rhodamine-6G and 3,3′-diethylthiacarbocyanine iodide was studied in aqueous solutions of sodium lauryl sulfate. A highly enhanced energy transfer was observed at very low dye concentrations in the premicellar region. This effect can be explained in terms of the formation of dye-rich mixed micelles. 相似文献
55.
Masahiro Kawasaki Kazuo Kasatani Hiroyasu Sato Hisanori Shinohara Nobuyuki Nishi 《Chemical physics》1984,88(1):135-142
Molecular beams of halogenated hydrocarbons containing chlorine and bromine atoms were photodissociated using an excimer laser at 193 nm. Molecules photodissociated were HCCBr, HCCCH2Br, HCCCH2Cl, CH3Cl, C2H5Cl and i-C3H7Cl. The time-of-flight distributions of the photofragments were measured in order to study the primary processes and the dissociation dynamics. Generalizations consistent with the data are that atomic products (RX → R + X) result from direct dissociation of the CX repulsive singlet state, molecular elimination (RX → R′ + HX) is a result of a crossover to the ground state and triplet states are involved in the photodissociation of alkyne compounds. 相似文献
56.
Considerable amounts of benzene were formed by heating triphenylphosphine complexes of transition metals in several types of organic compounds, especially in amines; in the case of a tributylphosphine complex, n-butane was detected. In the reactions with indoline, tetrahydroquinoline or dioxane, the hydrogen consumed for the hydrogenolysis was proved to arise from the amines or the ether. 相似文献
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58.
Ryosuke Sugiyama Takahiro Nakatani Shinichi Nishimura Kei Takenaka Taro Ozaki Shumpei Asamizu Hiroyasu Onaka Hideaki Kakeya 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13620-13625
Organisms often produce secondary metabolites as a mixture of biosynthetically related congeners. However, why are metabolites with minor chemical variations produced simultaneously? 5‐Alkyl‐1,2,3,4‐tetrahydroquinolines (5aTHQs) are small, lipophilic metabolites produced by Streptomyces nigrescens HEK616 when cultured with Tsukamurella pulmonis TP‐B0596. A mixture of 5aTHQs forms aggregates that show enhanced membrane affinity and biological activity. The ability to form aggregates and membrane‐binding activity is regulated by the length of the alkyl chains. Aggregates with long alkyl chains were too stable to fuse with lipid membranes. However, if inactive 5aTHQ congener was mixed with active congener, the mixture showed increased membrane affinity, enabling cellular entry and biological activity. Therefore, it is shown that sloppiness in a biosynthetic pathway, by which minor structural variations can be produced, is functionally rational, as the metabolites show synergistic action. 相似文献
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