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331.
The disadvantage of the extension of the Davidon-Fletcher-Powell method to infinite-dimensional space is that the information to be stored in the computer increases with the number of iterations. In this paper, a computational scheme is proposed to remove this disadvantage and make the extension method more practicable. The linear operator which determines the direction of one-dimensional search in the method is formulated by integral kernels to derive the scheme. Furthermore, polynomial interpolation methods are proposed to save computer storage. The computational scheme which is presented here and the polynomial interpolation method are successfully applied to an optimal control problem.The authors would like to thank Dr. N. Adachi for valuable discussion. Computations were carried out at the computing centers of Osaka University, Kyoto University, and Tokyo University. 相似文献
332.
Yasumitsu Matsuo Junko Hatori Seiichiro Ikehata 《Journal of Physics and Chemistry of Solids》2005,66(1):127-131
We have investigated the molecular motions of TRIS+ ([(CH2OH)3CNH3]+) and ions in the [(CH2OH)3CNH3]2SiF6 crystal below room temperature from the measurements of the spin-lattice relaxation time T1 and the NMR absorption line of 1H and 19F nuclei, in order to elucidate the changes of the molecular motions by the phase transition of Tc=178 K. The narrowing of the 19F-NMR line was observed around Tc=178 K and the reorientation of the anion appears above Tc. Moreover, from the analysis of the temperature dependence of T1, we have observed that the activation energy of the reorientational motion of ions changes from 0.168 eV (T>Tc) to 0.185 eV (T<Tc). Based on these results, we found that the reorientational motion of ions is closely related to the origin of the phase transition at Tc. In addition, from the measurement of the 1H-NMR line, we also found that the reorientational motion of H2 in the -CH2OH group becomes active accompanied by the phase transition. 相似文献
333.
Koji?SaganeEmail author Kazuhiro?Hayakawa Junko?Kai Tomoko?Hirohashi Eiki?Takahashi Norimasa?Miyamoto Mitsuhiro?Ino Tohru?Oki Kazuto?Yamazaki Takeshi?Nagasu 《BMC neuroscience》2005,6(1):33
Background
ADAM22 is a member of the ADAM gene family, but the fact that it is expressed only in the nervous systems makes it unique. ADAM22's sequence similarity to other ADAMs suggests it to be an integrin binder and thus to have a role in cell-cell or cell-matrix interactions. To elucidate the physiological functions of ADAM22, we employed gene targeting to generate ADAM22 knockout mice. 相似文献334.
Hitoki G Takata T Kondo JN Hara M Kobayashi H Domen K 《Chemical communications (Cambridge, England)》2002,(16):1698-1699
Under visible light irradiation (lambda = 420-500 nm), a tantalum oxynitride, TaON, functions as a stable and very efficient photocatalyst for oxidation of water into O2 with a sacrificial electron acceptor (Ag+). 相似文献
335.
We present a simple quantum network, based on the controlled-SWAP gate, that can extract certain properties of quantum states without recourse to quantum tomography. It can be used as a basic building block for direct quantum estimations of both linear and nonlinear functionals of any density operator. The network has many potential applications ranging from purity tests and eigenvalue estimations to direct characterization of some properties of quantum channels. Experimental realizations of the proposed network are within the reach of quantum technology that is currently being developed. 相似文献
336.
Fukutomi J Suzuki E Shimizu T Kimura A Fujiwara H 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,160(1):26-32
Experimental conditions that affect the degree of polarization of 129Xe gas were tested for a higher degree of polarization to facilitate a laboratory use of 129Xe NMR, primarily on the effect of addition of foreign gases. When He, N(2), or D(2) gas was added separately to pure Xe gas with natural isotope abundance, D(2) gas gave better results than the others in enhancing the degree of polarization in 129Xe atom. When these gases were added in mixture, however, N(2) plus He was proved to be more efficient than D(2) or He in enhancing the degree of polarization. As a result, the degree of polarization was found to be increased by more than an order, when diluent gases were properly mixed; polarization as high as 35% was reached at gas composition of 5% Xe, 10% N(2), and 85% He, whereas only a few percent was attainable when Xe gas was polarized without mixing any foreign gases [J. Magn. Reson. 150 (2), 156-160 (2001)]. These results were discussed on a basis of quenching and buffer effects of foreign gases. Polarization was also measured after separating the pure Xe gas from the mixture; value of 22% was obtained for the Xe gas isolated after solidification in liquid nitrogen trap. Build-up time of the polarization was also tested, which did not change remarkably depending on the gas composition. 相似文献
337.
Naoki Hirayama Noriko Sugisaka Junko Taga Syunichi Oshima Takaharu Honjo 《Analytical sciences》2003,19(2):321-324
"Substituent on benzenesulfonyl group" effect of 8-benzenesulfonamidoquinoline [N-(8-quinolyl)benzenesulfonamide, Hbsq] as bidentate chelate extractant for divalent metal cations was investigated with using Hbsq and its eight derivatives. Introduction of electron-withdrawing substituent on the benzenesulfonyl group in Hbsq enhanced the extractability that originated from its inductive effect. Furthermore, a bulky substituent on an ortho-position of the benzenesulfonyl group resulted in no steric effect in extraction, whereas the existence of two substituents on each ortho-position caused lower extraction performance due to steric hindrance. 相似文献
338.
Hisao Oka Yoshitomo Ikai Norihisa Kawamura Masuo Yamada Junko Hayakawa Ken-Ichi Harada Kazuko Nagase Hideaki Murata Makoto Suzuki Yoichiro Ito 《Journal of separation science》1991,14(5):306-311
The analytical capability of the high speed countercurrent chromatograph model 4000 (HSCCC-4000) has been improved by optimizing the dimensions of the multilayer coiled column. Using a two-phase solvent system of n-hexane – ethyl acetate – methanol – water (1:1:1:1) and a set of indole auxins as test samples, a series of studies was conducted to evaluate performance of coiled columns with i.d.s ranging from 0.1 to 0.55 mm. The studies on the stationary phase retention indicated that multilayer coils of 0.55 mm and 0.30 mm i.d. provide satisfactory retention of the stationary phase while the 0.10 mm i.d. column fails to yield reproducible retention. The best partition efficiencies were obtained from the 0.30 mm i.d. multilayer coil with a 6 ml capacity which produced theoretical plate numbers ranging from 5500 to 10500 with a resolution factor of 2.30. The feasibility of interfacing the HSCCC-4000 with a mass spectrometer is briefly discussed. 相似文献
339.
Fifteen samples of sodium poly(styrene sulfonate) with weight‐average molecular weights of 3 × 104 to 8 × 105 have been studied by static and dynamic light scattering and viscometry in 0.05 and 0.5 M aqueous NaCl at 25 °C. The measured radii of gyration, translational diffusion coefficients, and intrinsic viscosities at the lower salt concentration exhibit molecular weight dependencies stronger than those predictable for uncharged flexible chains in the good solvent limit. These data and those at the higher NaCl concentration are analyzed, along with previous intrinsic viscosity data covering a broad molecular weight range, in the framework of the quasi‐two‐parameter (QTP) theory with the wormlike chain as the model. It is shown that the relevant theories for the expansion factors in the QTP scheme combined with these theories for the unperturbed wormlike chain are capable of describing the experimental data with a degree of accuracy similar to that known for nonionic flexible polymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2728–2735, 2002 相似文献
340.
Yoshiko Oi Nakamura 《Solid State Communications》1981,39(6):763-765
Using the hydrodynamic jellium model, it is shown that a surface plasma oscillation excited at the surface of the semi-infinite metal induces a finite amount of angular momentum to the system, so that, it is conjectured that the surface plasmon has a spin quantum number S = 1 with a definite polarization. 相似文献