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901.
X-ray diffraction studies have been undertaken on aqueous solutions of hydroxy propylcellulose (HPC) over a wide range of the scattering vector Q. The experiments revealed only modest differences in local structure on a distance scale ca. 5–300 Å despite the fact that they covered concentrations generally interpreted as ranging from the isotropic (35.1 wt %) to the anisotropic liquid crystalline (LC) phase (53.5 wt %). Several models were used to interpret the small-angle scattering data, and each gave similar structural parameters and extrapolated intensities ( Q → 0) for both solutions. Peaks were observed with d-spacings ca. 12–17 Å in both materials. Wide-angle x-ray scattering (WAXS) showed slightly increased local order over a size range ca. 5–20 Å for the anisotropic solution, and this is consistent with a greater intensity of the 13 Å peak in this material. It is difficult to reconcile these findings with an interpretation of the LC state involving major differences with the isotropic phase and a high degree of orientational order extending over long length scales. 相似文献
902.
903.
Angular momentum effect in prescission particle multiplicities for a light system by diffusion model
W. Ye W. Q. Shen Z. D. Lu J. Feng Y. G. Ma J. S. Wang K. Yuasa-Nakagawa T. Nakagawa 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(4):385-389
The effect of angular momentum on the competition between fission and particle emission during light system fission process was studied via fission diffusion model. The prescission particle multiplicities were found to increase with decreasing angular momentum. The experimental prescission proton and α particle multiplicities can be fitted for 10.6 MeV/nucleon 84Kr(27Al,binary fission) reaction with this model. Entrance channel effect found in [1] is proved to be angular momentum effect. 相似文献
904.
905.
A holographic image subtraction technique is proposed. The vector nature of light is utilized in introducing a phase difference of π between the two reconstructed object waves. The experimental results are also presented. 相似文献
906.
Hyperfine Interactions - Conversion electron Mössbauer spectroscopy measurements have been made on a diamond sample synthesized by chemical vapour deposition. The sample was implanted with 70... 相似文献
907.
908.
The dependence of the formation of a p-n or p-p+ junction in semiconducting TiO2 as a function of various parameters is investigated through a computer model. The effect of the polarizing conditions on
the I–V characteristics is also discussed and related to experimental results.
Paper presented at the 3rd Euroconference on Solid State Ionics, Teulada, Sardinia, Sept. 15–22, 1996 相似文献
909.
910.
V. N. Lopatin A. D. Aponasenko N. V. Shepelevich 《Journal of Applied Spectroscopy》1997,64(6):825-831
We investigate the possibilities of creating a method for estimating the optical constants, dimensions, and concentrations
of “soft” absorbing particles by applying a theoretical analysis of the angular dependence of the intergrated indicatrix,
overall characteristics of light scattering, and absorption on the phase shift and diffraction parameter of particles in the
brightening band region. We show that using the investigated optical characteristics, it is possible to determine the unknown
parameters of a suspension from experimental data.
Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russia. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 6, pp. 807–812, November–December, 1997. 相似文献