共查询到20条相似文献,搜索用时 78 毫秒
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结出了双重Q^2重标度模型的重标度参数经验公式,其中建立了重标度参数ξV,ξS及ξG与原子核平均结合能之间的联系,利用这套公式可以给出A≥12的所有核的重标度参数值,进而可以采用这些重标度参数值计算有关核过程做出预言。 相似文献
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利用低能轻离子在固体中的输运量可近似由离子标度输运截面单值描述这一标度特性,取得了计算低能轻离子在重靶中射程分布的普适公式,具体地,在用离子输运双群模型计算得到射程分布前四阶矩后,建立这些与标度输运截面之间的近似单值对应关系,在此基础上,拟合得到计算射程分布的前四阶矩以及射程分布的公式.通过与实验值和MonteCarlo计算结果的比较,检验了本文给出的普适公式.利用本文的结果可以较好描述低能轻离子在固体中的射程分布,同时又有很高的计算效率.
关键词: 相似文献
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在AHP应用中提出了各种各样的标度,在分析比较各种标度后,得出指数标度是核心标度的结论,证明了1-9标度与指数标度不相容,指出许多标度实质上只是指数标度的特例,提出了确定指数标度参数的方法,并指出了应用指数标度时应注意的问题及其解决办法。 相似文献
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A relevant problem regarding entanglement measures is the following: Given an arbitrary mixed state, how does a measure for multipartite entanglement change if general local operations are applied to the state? This question is nontrivial as the normalization of the states has to be taken into account. Here we answer it for pure-state entanglement measures which are invariant under determinant-one local operations and homogeneous in the state coefficients, and their convex-roof extension which quantifies mixed-state entanglement. Our analysis allows us to enlarge the set of mixed states for which these important measures can be calculated exactly. In particular, our results hint at a distinguished role of entanglement measures which have homogeneous degree 2 in the state coefficients. 相似文献
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We present a new symmetry flow of the Kadomtsev-Petviashvili (KP) hierarchy, which origins from the rescaling of whole “multi-time“ valuables. This flow describes the deformation of solutions of the KP hierarchy with respect to a noncommutative parameter. It is shown that the introduced rescaling symmetry flow does not commute with the ordinary evolution flows of the KP hierarchy, but commutes with the evolution flows with respect to slow-variables. 相似文献
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Laser-induced autofluorescences show a strong intensity distortion for endogenous NADH in the UV and synthesized markers in the NIR range because of tissue optics. Rescaling taking into account bio-optical methods results in the chromophore profile in the observed tissue region. For the in vivo tests an experimental NIR imager was used. NIR fluorescence of the entire body of small animals can be imaged. For first experiments an undifferentiated superficial tumor of mouse thigh was used. Corrections that are due to tissue optics must take care of a more strongly scattering of the light in the NIR range in comparison to the UV fluorescence such as in optical biopsy. For example, the diameter of the fluorescent volume is apparently larger for the same reason. Therefore, the established rescaling from the UV adapted to the NIR range is important for the interpretation fluorescence pictures in biomedicine. 相似文献
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A rescaling procedure is proposed for electron spin echo envelope modulation spectra observed at several electron paramagnetic resonance transitions. Analytical expressions describing the relations between the rescaled frequencies and hyperfine and quadrupole parameters of the remote nucleus are obtained. The dependences of the rescaled data on the external magnetic field and spin projections of the ion nucleus and the remote nuclei are used to derive the parameters of the nuclear state in the crystals Y2SiO5 and YVO4 doped by ion Nd3+. 相似文献
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《Physics letters. A》1998,244(4):237-244
The numerical treatment of anomalous diffusion shows that in some cases Hurst's analysis and the second moment technique express the long-range properties by means of distinctly different rescaling coefficients. With theoretical arguments we show this effect to be determined by the finite speed of the propagation front. 相似文献
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K. Knorr B. Renker W. Assmus B. Lüthi R. Takke H. J. Lauter 《Zeitschrift für Physik B Condensed Matter》1980,39(2):151-158
The phonon dispersion of LaAg
x
In1–x
(x=1, 0.89, 0.8) has been studied by inelastic neutron scattering in the cubic high temperature phase. A soft mode behaviour was observed at theM-point. The doubling and the cubic to tetragonal deformation of the elementary cell was observed through the phase transition. The measurements of the elastic constants were extended to 450 K and their magnetic field dependence was investigated.This work was supported by the BMFT and the Sonderforschungsbereich 65 Darmstadt/Frankfurt 相似文献
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Mössbauer spectroscopy, X-ray photoemission spectroscopy and magnetization studies of EuCu2?x Fe x Si2, EuCu2Si2?x Ge x , EuCu2?x Si2+x , and EuNi2?x Si2+x have been performed. In EuFe2Si2 and EuNi2Si2 the Eu ion is trivalent, in EuCu2Si2 it is of intermediate valency. In all systems withx=0, many inequivalent Eu sites of intermediate valency are formed. In EuCu2?x Fe x Si2, the average valency of Eu moves nonmonotonically toward Eu3+. In EuCu2Si2?x Ge x , EuCu2?x Si2+x and EuNi2?x Si2+x , the Eu average valency moves quickly towards Eu2+. In all three systems, whenx=1, all Eu ions are already stable divalent. The systems EuCuSi3 and EuNiSi3 order magnetically at 40 K and 34 K, and exhibit hyperfine fields of 323 kOe and 458 kOe, respectively. XPS and Mössbauer isomer shift determinations of the average Eu valence as a function of temperature in EuCu1.5Fe0.5Si2 are in good agreement. The experimental observations concerning the Eu valencies can not be explained solely in terms of the local volume available to the Eu ion; the nature of chemical environment plays a dominant role. 相似文献
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Magnetization and119Sn Mössbauer spectroscopy studies were performed on two pseudoternary systems, namely U x Th1?x CoSn and UCoAl1?x Sn x . Magnetic hyperfine fields on119Sn nuclei were found to be due to local surrounding of U atoms which carry magnetic moments. In pure UCoSn the valuesB hf=8.66 T and μ∪ satisfy the relationB hf=6.75 μB found for a number of UTX compounds studied. Local surrounding effects are indicated by multicomponent spectra obtained for the two pseudoternary series. 相似文献
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E. Pollert 《Czechoslovak Journal of Physics》1973,23(4):468-472
The phase composition of the mixed oxides, series LiMe
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V2–x
O4, where Me=Zn, Mg, was studied using X-ray analysis. The minor phases present in the investigated samples together with the basic spinel phase were determined as Li3VO4 and Zn2V2O7 or Mg2V2O7 respectively. Their presence is caused by the tendency of tetravalent vanadium ions to the disproportionation. For the compositionsx=0·375 were determined the quantitative phase compositions. The lattice constant of the spinel phase is linearly changing according to Vegard's rule, for the zinc series in the range 0x0·375 and for the magnesium series in the range 0xs0·25. Further substitution in magnesium series caused tetragonal deformation of the cubic spinel lattice.The author is indebted to Dr. A.Bergstein for helpful discussions and to Mrs. E.Hrubá for technical assistance. 相似文献