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991.
A model of a divacancy which explains a number of experimental facts for Ge exposed to a flow of accelerated electrons at temperature T=77 K is proposed. The model explains the absence of photoconduction associated with photoexcitation of infrared absorption bands at 0.44 and 0.52 eV corresponding to divacancies; the difference in the values of activation energy for divacancy energy levels determined by optical and electrical methods; and the existence of the limiting position of the Fermi level in the forbidden gap in the case of irradiation with large radiation fluxes. 相似文献
992.
This paper summarizes a set of novel techniques for obtaining optical transformations, which are useful tools for signal processing. Then the paper focuses on deriving several interesting discrete transformations. The discussed transforms include continuous fractional transformations, hybrid transforms and discrete transform kernels. 相似文献
993.
I. G. Alekseev P. E. Budkovsky V. P. Kanavets L. I. Koroleva B. V. Morozov V. M. Nesterov V. V. Ryltsov D. N. Svirida A. D. Sulimov V. V. Zhurkin Yu. A. Beloglazov A. I. Kovalev S. P. Kruglov D. V. Novinsky V. A. Shchedrov V. V. Sumachev V. Yu. Trautman N. A. Bazhanov E. I. Bunyatova 《Physics of Atomic Nuclei》2002,65(2):220-228
New experimental data on the spin-rotation parameters A and R measured for elastic π ± p scattering in the resonance region and on the asymmetry in pC scattering at primary momenta in the range 1.35–2.02 GeV/c, as well as in quasielastic proton scattering on nuclei in the same momentum range, are summarized. All these data were recently obtained by using the proton synchrotron installed at the Institute of Theoretical and Experimental Physics (ITEP, Moscow). The spectrum and features of seven isospin-3/2 baryon resonances that form a peak in the total cross section at a c.m. energy of 1.9 GeV are analyzed on the basis of new data on the parameters A and R, and the results of this analysis are presented. The experiments surveyed in this article were performed by a collaboration of researchers from ITEP and the Petersburg Nuclear Physics Institute (PNPI, Gatchina), the ITEP-PNPI collaboration. 相似文献
994.
Maksimov R. D. Zicans J. Ivanova T. Negreeva S. N. Plume E. 《Mechanics of Composite Materials》2002,38(2):141-148
The results of experimental and theoretical investigations of elastic and thermophysical properties of poly(vinyl chloride) (PVC) and chlorinated polyethylene (CPE) blends are presented. Eight types of specimens with different ratios of weight contents of PVC and CPE (PVC/CPE = 100/0, 90/10, 80/20, 60/40, 40/60, 20/80, 10/90, and 0/100) were tested. The effect of blend composition on the elastic constants (tensile and shear modulus) is discussed. The data on the thermal conductivity, thermal diffusivity, and heat capacity of the blends investigated are also presented. 相似文献
995.
996.
R. S. Dias A. P. Roque D. M. S. S. Vitti 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(3):661-663
Summary The objective of this study was to determine endogenous phosphorus excretion in sheep fed with different diets. Sixteen male
growing sheep, received a basic diet with: 42% hydrolyzed sugarcane bagasse (HSB), 45% lucerne hay (LH) plus 14% hydrolyzed
sugarcane bagasse, and 30% citrus pulp (CTP) plus 40% hydrolyzed sugarcane bagasse. A dose of 7.7 MBq 32P was injected into the left jugular vein of each animal. The P endogenous fecal losses were: 1.69, 2.50, 2.33 and 1.45 g/animal
for treatments HSB, LH, and CTP respectively (P>0.05). The type of diet influenced slight endogenous P excretion but altered
excretion of P in urine. Endogenous P excreted in feces (PF) comes mainly from saliva and represents an important loss of P. The estimation of net requirements of phosphorus (P) for
ruminants includes endogenous losses, which is also essential for calculating true absorption of this mineral. Physical structure
of the feed may influence endogenous losses, altering the metabolism of P and also the demand of this mineral, therefore being
important to know how different feeds affect endogenous P losses. 相似文献
997.
A graphite electrode modified with cobalt hexacyanoferrate by mechanical immobilization was used for amperometric determination of hydrazine. The modified electrode exhibits good catalytic activity for the oxidation of hydrazine at a reduced overpotential with remarkable sensitivity. The modified electrode showed a linear response for hydrazine in the concentration range of 2.0 × 10–5 to 2.8 × 10–4 M. The detection limit was 9.8 × 10–6 M (S/N = 3). The proposed modified electrode was simple, sensitive, rapid, stable and promising. 相似文献
998.
D. P. Kozlenko S. E. Kichanov S. Lee J. -G. Park V. P. Glazkov B. N. Savenko 《JETP Letters》2006,83(8):346-350
The effect of a high pressure (up to 6 GPa) on the crystal and magnetic structure of the hexagonal manganite LuMnO3 is studied by neutron diffraction in the temperature range 10–295 K. It is found that, as the pressure increases, the ordered magnetic moment of Mn ions at T = 10 K decreases noticeably from 2.48 (0 GPa) to 1.98 μB (6 GPa). This decrease is due to an enhancement of the geometrical frustration effects on the triangular lattice. At the same time, the symmetry of the triangular antiferromagnetic state (the irreducible representation Γ2) remains unchanged. A correlation is revealed between the distortion parameter of the triangular lattice formed by Mn ions and the symmetry of the antiferromagnetic state of hexagonal manganites RMnO3. Based on this correlation, a generalized magnetic phase diagram of these compounds is constructed. The obtained phase diagram provides an explanation for the changes observed in the magnetic state of hexagonal manganites caused by high pressure and chemical substitution. 相似文献
999.
D. Liu Y. Li R. An Y. Dou H. Yang Q. Gong 《Applied Physics A: Materials Science & Processing》2006,84(3):257-260
We studied the influence of focusing depth on the index change threshold and damage threshold of silica glass irradiated by a focused 120 fs laser beam. Both thresholds increased with the focusing depth. The aspect ratio of the waveguide cross section can be selected by changing the focusing depth. A 5 mm long waveguide was written at the depth of 2100 μm, which was single mode at 632.8 nm and exhibited propagation loss of 0.56 dB/cm. The refractive index change was calculated to be ∼2.47×10-3. The influence of the focusing depth should be considered in multi-layer devices as shown in the fabrication of a 3×3 waveguide array. PACS 42.62.-b; 42.82.Et; 81.05.Kf 相似文献
1000.
P. F. Mantica Jr. B. D. Kern B. E. Zimmerman W. B. Walters J. Rikovska N. J. Stone 《Hyperfine Interactions》1992,75(1-4):415-421
The performance of two external plastic scintillator detectors has been tested in an off-line mode using a source of106RuFe at UNISOR/NOF. The measurement of beta asymmetries at various temperatures has resulted in the reproduction of the previously-determined
magnetic dipole moment for the 1+ ground state of106Rh and in addition the conclusion that the sign of this moment is positive. 相似文献