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31.
利用量子统计方法 ,直接计算Barriola_Vilenkin黑洞背景下玻色场和费米场的配分函数 ,然后利用砖墙膜模型计算和讨论黑洞背景下玻色场和费米场的熵 相似文献
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Changes in thin zinc-sulfide films under the action of the γ-radiation of Co60 are studied by investigating electroluminescence spectra of terbium embedded in these films as a luminescent probe. It is
shown that changes in the relation of the intensities of bands, a decrease in their halfwidth and the background component,
and simplification of the spectrum are observed in a short-wave region of the Tb radiation spectrum that corresponds to5D3→7Fj transitions. The same modification of the radiation spectrum is characteristic of ZnS films whose crystalline structure is
ordered in the course of thermal annealing at a temperature of 350°C. Based on the analysis of the data obtained it is inferred
that irradiating the ZnS films with small radiation doses of 104–105 rad leads to the ordering of their crystalline structure due to the elimination of one of the types of structural defects.
Institute of Physics of Semiconductors, National Academy of Sciences of Ukraine, 45, Nauka Ave., Kiev-28, 252650. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 338–341, May–June, 1997. 相似文献
36.
A. P. Prishivalko 《Journal of Applied Spectroscopy》1997,64(1):94-100
A method for finding the optimum sizes of pigment particles, their volume concentration, and the paint coating thickness that
provide the covering power and the required coloristic characteristics of reflected light for the minimum flow rate of pigments
is based on using a four-flow approximation of the solution to the equation of radiation transfer in dispersion media and
is extended to coatings of complex composition. The capabilities of the method are demonstrated by examples of coatings of
mixtures of hematite and rutile particles in a binder with n=1.5 for variations of the modal size and the half-width of the
size distribution of the pigment particles.
B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 90–96, January–February, 1997. 相似文献
37.
A highly sensitive method for infrared radiation detection based on thermal resonance in an active bolometer is set forth. An active bolometer is a self-oscillating system consisting of an IR-sensitive cell in a feedback circuit of an adjustable proportional controller. The analysis of an active bolometer autonomous (dark) dynamics reveals that with a generalized gain factor A variation the system evolves from relaxation type towards oscillating and self-oscillating type. When A=Ac, where Ac is a critical value of the generalized gain factor A, the steady state loses stability through self-excited thermal oscillations. The resonance in a system weakly perturbed by IR radiation modulated at self-oscillation frequency q0[1+exp(iωct)] is considered. It is shown that in a small precritical vicinity =(A−Ac)/Ac of the gain factor the amplitude of forced thermal oscillations is proportional to q0/Ac. The D* calculation reveals that the detection power of a passive (A=0) bolometer increases with feedback introduction by a factor of 1/||. The detection powers of feasible versions of an active bolometer are compared. 相似文献
38.
I.IntroductionWhenastructurcvibratcs,itsvibratingsurfacewillmakesurroundingmediummovetogethcrwithit.Ifthernotionissofastthatthcmediumroundthestructureproduccaloca1contractionandcxpansionandthcypropagatefaraway,thesoundradiationisformed.Itispossiblctodcscribeanalytica11ytheradiationfic1dofsimplyandregularlyshapcdsourcessuchaspointsoundsourccs,spherica1soundsourccsandinflnite1engthllnearsoundsourccs,butitisa1mostimpossib1ctosolvetheradiationfiledbyanyanalyt-ica1methodforsourcesofvcrycomplicateds… 相似文献
39.
在e-A深度非弹性散射过程中, 喷注穿过冷核介质时, 多重散射诱导胶子辐射会导致对碎裂函数的修正及喷注的能量损失.前期研究中关于计算e-A深度非弹性散射中胶子辐射振幅的两种方法: 螺旋振幅近似和微扰QCD严格计算都异常繁杂.
本文发展了一种新的方法, 可以方便计算出多重散射导致胶子辐射的振幅, 得到的碎裂函数的修正以及能量损失与严格计算的结果一致. 相似文献
40.
For approximate wave functions, we prove the theorem that there is a one‐to‐one correspondence between the constraints of normalization and of the Fermi–Coulomb and Coulomb hole charge sum rules at each electron position. This correspondence is surprising in light of the fact that normalization depends on the probability of finding an electron at some position. In contrast, the Fermi–Coulomb hole sum rule depends on the probability of two electrons staying apart because of correlations due to the Pauli exclusion principle and Coulomb repulsion, while the Coulomb hole sum rule depends on Coulomb repulsion. We demonstrate the theorem for the ground state of the He atom by the use of two different approximate wave functions that are functionals rather than functions. The first of these wave function functionals is constructed to satisfy the constraint of normalization, and the second that of the Coulomb hole sum rule for each electron position. Each is then shown to satisfy the other corresponding sum rule. The significance of the theorem for the construction of approximate “exchange‐correlation” and “correlation” energy functionals of density functional theory is also discussed. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献