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21.
22.
Our study of internal rotation was carried out under the guidance of Professor San—ichiro Mizushima. Dipole moment measurements of 1,2-dichloroethane in non-polar solvents revealed a temperature dependence of the moment, which was interpreted as an indication of the existence of hindered rotation about the central CC bond, contrary to the original assumption of free rotation by van't Hoff and Le Bel. Raman Spectroscopy confirmed that the solid phase consists of the trans form only, whereas in the liquid and in the gas phases a second stable isomer coexists with the trans form. This second form was called > gauche< by Mizushima and its geometrical structure was established by electron diffraction. The potential function for internal rotation is considered with regard to its experimental determination and its interpretation by ab initio calculations. 相似文献
23.
Nakamichi S Kawaguchi Y Fukuda H Enami S Hashimoto S Kawasaki M Umekawa T Morino I Suto H Inoue G 《Physical chemistry chemical physics : PCCP》2006,8(3):364-368
Buffer-gas pressure broadening for the (3 0(0) 1)(III)<--(0 0 0) band of CO(2) in the 1600 nm region was investigated with continuous wave cavity ring-down spectroscopy within the temperature range 263-326 K. The measured absorption profiles were analyzed with Voigt functions. Pressure broadening coefficient, gamma(gas), and the temperature dependent parameter (broadening exponent), n, were determined for a variety of buffer gases: N(2), O(2), He, Ne, Ar, Kr and Xe. gamma(air) values estimated subsequently are 0.096(2) for R(0), 0.085(5) for P(8), 0.075(2) for P(16), 0.070(4) for P(26), and 0.069(2) for P(38) in units of cm(-1) atm(-1), where numbers in parentheses are one standard deviation in units of the last digits quoted. n(air) values are 0.77(4) for R(0), and 0.73(11) for P(8). 相似文献
24.
A.V. Nikitin S.N. Mikhailenko N.N. Filippov I. Morino R. Kumazawa 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(15):2211-2224
A methane spectral line list for the 5550-6236 cm−1 range with the intensity cut off 4×10−26 cm/molecule at 296 K is presented. The line list is based on new extensive measurements of methane spectral line parameters performed at different temperatures and pressures of methane and buffer gases N2, O2 and air. This spectral line list is prepared in HITRAN-2008 format and contains the following spectral line parameters of about 11,000 lines: position, intensity, energy for lower state (where possible), air-broadening and air-shifting coefficients, exponent of temperature dependence of air-broadening coefficient and self-broadening coefficient. 相似文献
25.
[Structure: see text] tert-Butyl hypoiodite (t-BuOI) was found to be a powerful reagent for the cyclization of N-alkenylamides leading to a variety of N-heterocycles under extremely mild conditions. When N-alkenylsulfonamides were employed in the reaction, three- to six-membered saturated N-heterocycles were obtained in good to excellent yields with complete stereoselectivity. The method was applicable to the cyclization of alkenylbenzamide derivatives to afford N-, O- or N-, S-heterocycles. 相似文献
26.
Takezawa Y Tanaka K Yori M Tashiro S Shiro M Shionoya M 《The Journal of organic chemistry》2008,73(16):6092-6098
Metal-mediated base pairing with artificial ligand-bearing nucleosides allows site-selective metal incorporation inside DNA duplexes. In particular, this strategy has provided a general way of discrete, heterogeneous metal arrays in a programmable manner. To increase the kind of metallo-building blocks, we have newly synthesized two artificial nucleosides which have an O, S-donor ligand as the nucleobase moiety, mercaptopyridone ( M) and hydroxypyridinethione ( S). These nucleosides were found to efficiently form metal-mediated base pairs with soft transition metal ions such as Pd (2+) and Pt (2+). 相似文献
27.
28.
An optically active helical poly(phenylacetylene) was synthesized by the copolymerization of phenylacetylenes bearing optically active hydroxy or ester groups obtained by the kinetic resolution of a racemic phenylacetylene with lipase; the helix-sense was inverted from one helix to another by the further chemical modification of the hydroxy groups with achiral bulky isocyanates or an acid chloride. 相似文献
29.
We consider an eigenfunction problem for a system of Lamé equations in a three-dimensional parallelepiped in the case of a
mixed boundary-value condition on the boundary. By using Steklov averaging operators, the approximation error is given in
divergent form. The accuracy of the difference scheme is studied for generalized solutions from the spaceW
2
3(Ω). An O(|h|1.5)-estimate is obtained for eigenfunctions in the grid metric ofW
2
1(ω). Bibliography: 5 titles.
Translated fromObchyslyuval'na ta Prykladna Matematyka, No. 81, 1997, pp. 100–109. 相似文献
30.
Maiko Shigeno 《Mathematical Programming》2006,107(3):439-459
This paper deals with a generalized maximum flow problem with concave gains, which is a nonlinear network optimization problem.
Optimality conditions and an algorithm for this problem are presented. The optimality conditions are extended from the corresponding
results for the linear gain case. The algorithm is based on the scaled piecewise linear approximation and on the fat path
algorithm described by Goldberg, Plotkin and Tardos for linear gain cases. The proposed algorithm solves a problem with piecewise
linear concave gains faster than the naive solution by adding parallel arcs.
Supported by a Grant-in-Aid for Scientific Research (No. 13780351 and No.14380188) from The Ministry of Education, Culture,
Sports, Science and Technology of Japan. 相似文献