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181.
Out of a total statistics of 896139La+Ag(Br) interactions, 128 interactions having multiplicity of target fragments (Z⩾1)⩾8 and projectile fragments (Z⩾2)⩾4 have been selected. They correspond to quasi-peripheral interactions. Azimuthal angle correlation between sources of
target fragments (TFs) and projectile fragments (PFs) shows the existence of bounce-off effect. Using data of La+Ag(Br) and84Kr+Ag(Br) reactions it is shown that individual helium [Z=2, PFs] and heavier fragment [Z⩾3, PFs] show different emission characteristics. Further, a two prong correlation functionT(Φ
ij
) plotted for heavier fragments and helium fragments separately, indicates the possibility of existence of different physical
conditions. This observation is supported by the different momentum widths of helium fragments and heavier fragments. From
the momentum width data of Kr+Ag(Br) reactions normalized density comes out to be ≈4.7. Using quasi-elastic kinematics for
the bounce-off nuclei, the excitation energy has been computed from the experimental data of flow angles. The strength of
bounce-off seems to decrease with the increase of excitation energy or temperature. 相似文献
182.
The behavior of zirconium atoms at the W(100) surface associated with oxygen adsorption at different sample temperatures has been studied by Auger electron spectroscopy (AES), ion scattering spectroscopy (ISS), and the relative change of the work function (Δф) measured by the onset of the secondary electron energy distribution. The results have revealed: (i) adsorption of zirconium onto the W(100) surface followed by the elevation of the sample temperature up to 1710 K in an oxygen partial pressure of 2.7 × 10−4 induces complete diffusion of zirconium atoms into the W(100) substrate; (ii) further exposure of oxygen induces co-existence of oxygen and tungsten on the surface at 1710 K, resulting in a work function of 4.37 eV; (iii) keeping the sample temperature at 1710 K, simple evacuation of the system has resulted in surface segregation of zirconium atoms to the surface to form a zirconium atomic layer on the top-most surface, reducing the work function to 2.7 eV. The results have revealed that this specific behavior of zirconium atoms at high temperature assures, with very good reproducibility, the highly stable performance and long service life of Zr---O/W(100)-emitters in practical use, even in a low vacuum of 10−6 Pa. 相似文献
183.
S. A. Patlazhan 《Journal of Polymer Science.Polymer Physics》1993,31(12):1649-1665
A statistical theory of light scattering from deformed isotropic and textured heterogeneous polymer materials is formulated. Two types of textured structures are analyzed: assemblies of optically isotropic and anisotropic rods and a spatially anisotropic distribution of isotropic spherical inclusion centers. The small-angle Hv light-scattering patterns are calculated. The appearance of scattering from isotropic rods and spheres in deformed materials has been demonstrated. The changes of the Hv scattering patterns as a function of elongation and strucuture parameters are discussed. © 1993 John Wiley & Sons, Inc. 相似文献
184.
IR LASER BACKSCATTERING FROM AN ARBITRARILY SHAPED DIELECTRIC OBJECT WITH ROUGH SURFACE 总被引:2,自引:0,他引:2
吴振森 《电子科学学刊(英文版)》1993,10(4):298-306
The backscattering of light wave from arbitrarily convex dielectric objects withrough surface is investigated and formulas for calculating the backscattering cross-section of bothcoherent and incoherent fields are obtained.In the infrared wave-band,the influence of the ge-ometry,permittivity and statistical characteristics of the rough surface on LRCS is analyzed,byusing rough sphere and ellipsoids as examples. 相似文献
185.
工业污染排放中气──固两相流的光学测量 总被引:1,自引:0,他引:1
烟尘及各种工业性粉尘排放是典型的气-固两相系.迄今为止,国内外尚缺少有效的监测其排放的手段.本文基于光的散时原理,提出了一种非接触的光学方法,能对上述固体颗粒物的污染排放浓度及粒径大小进行实时、在线的监测。计算机模拟和实验研究表明,该方法具有广阔的工业应用前景。 相似文献
186.
187.
188.
We have studied electron energy relaxation in GaInAs/AlInAs heterojunctions and GaAs/AlGaAs multiple quantum wells using mobility measurements as a function of electric field and temperature, in the range 3K to 300K. The results in the range 3 to 20K show a power loss rate which is dependent on (Te − Tl), suggesting that the energy relaxation occurs through acoustic phonon scattering. At electron temperatures greater than 20K, the experimental results are modelled using a standard expression for polar optical phonons. This modelling yields 30meV and 31meV for the polar optical phonon energy in GaAs and InGaAs respectively. 相似文献
189.
190.
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