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901.
用于多波长高功率激光能量测量的体吸收能量计 总被引:2,自引:1,他引:1
叙述体吸收激光能量计的原理及物理模型,给出其性能参数及测试方法,分析它在神光Ⅱ装置中对三种波长激光能量测量的取样方式及测量精度。 相似文献
902.
The boundary integral equation formulation of thermoelasticity problems from part I is applied to crack problems in both finite and infinite thermoelastic bodies. For a flat crack in an infinite body the normal and tangential crack opening displacement are decoupled. Transient and steady state problems of thermoelasticity, as well as stationary problems, are considered. 相似文献
903.
L. H. Yu 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(3):539-544
A circular membrane with an arbitrarily placed internal strip of small length is
concerned in this article. A two-term asymptotic expansion for the fundamental frequency of the
membrane, as the length of the strip approaching to zero, is specified. Comparing it with the one
[8] derived for the membrane with an internal circular core, it is found that the position of
the internal constraint has more effect than the shape of the internal constraint on the
fundamental frequency. The asymptotic approximation is also compared with the numerical data
computed by the dual boundary element method [2] for a circular membrane of radius 1 with a
radially placed internal strip of length
2c. These two sets of data are in good agreement. The
relative error is less than 3 % as
c
is less than or equal to 0.1, for all positions of the
strip. Moreover, the relative error is less than 1 % as c is less than or equal to 0.01. 相似文献
904.
905.
P.S. Ganas 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,1(2):165-167
An analytic atomic independent-particle-model is used to generate wave functions for the valence and excited states of the
neutral phosphorus atom. These wave functions are used to calculate generalized oscillator strengths, and from these quantities
the cross sections are obtained in Born approximation. Various excitations from the ground state are considered, and results are presented for electron impact energies up to 5 keV.
Received: 6 May 1997 / Revised: 21 October 1997 / Accepted: 5 December 1997 相似文献
906.
In this work, some classes of initial boundary-value problems are investigated in the Sobolev space for the third-order linear pseudoparabolic equation having, in general, nonsmooth coefficients. A new type of Riemann function concept is given for these problems, which is more natural than the classical Riemann-type function concept, and an integral form of the solutions of nonhomogeneous problems can be found more naturally using this concept. 相似文献
907.
R. Muhida M. David M. M. Rahman W. A. Diño H. Nakanishi H. Kasai K. Fukutani T. Okano 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(1):99-101
We investigate the molecular orientation dependence of the (o)rtho-(p)ara H2 conversion on Fe(OH)3 cluster. Taking Fermi's contact interaction as perturbation, we find that the o-p H2 conversion yield for the molecular orientation angle θ= 10○ with respect to the surface normal is larger than that for θ= 70○. 相似文献
908.
A model for the γp → π+π−p reaction developed earlier is extended to account for all isospin channels. The model includes N, Δ(1232), N*(1440) and N*(1520) as intermediate baryonic states and the meson as an intermediate 2π resonance. Although many terms contribute to the cross section, some channels exhibit particular sensitivity to certain mechanisms of resonance excitation or decay and the reactions provide novel information on such mechanisms. In particular the γN → N*(1520) → Δπ process affects all the channels and is a key ingredient in the interpretation of the data. Comparison is made with all available data and the agreement is good in some channels. The remaining discrepancies in some other channels are discussed. 相似文献
909.
V. P. Leksin 《Mathematical Notes》2006,79(3-4):533-536
In this paper, it is proved that the intersection of the radicals of nilpotent residues for the generalized pure braid group corresponding to an irreducible finite Coxeter group or an irreducible imprimitive finite complex reflection group is always trivial. The proof uses the solvability of the Riemann—Hilbert problem for analytic families of faithful linear representations by the Lappo-Danilevskii method. Generalized Burau representations are defined for the generalized braid groups corresponding to finite complex reflection groups whose Dynkin—Cohen graphs are trees. The Fuchsian connections for which the monodromy representations are equivalent to the restrictions of generalized Burau representations to pure braid groups are described. The question about the faithfulness of generalized Burau representations and their restrictions to pure braid groups is posed. 相似文献
910.
采用高温固相方法合成了(Y,Gd)(P,V)O4∶Eu3 ,经X射线结构分析确定为四方晶系,体心结构,空间群为I41/amd[141]。研究了(Y,Gd)(P,V)O4∶Eu3 在VUV及UV激发下的光谱特性,讨论了激活剂Eu3 的浓度对发光亮度的影响。(Y,Gd)(P,V)O4∶Eu3 荧光粉的发射主峰在619 nm,证明Eu3 离子占据了非反演对称中心的位置。在(Y,Gd)(P,V)O4∶Eu3 (监控619 nm)的激发谱,有一个中心位于156 nm的吸收带,它属于基质的吸收带。将(Y,Gd)(P,V)O4∶Eu3 的发光性能与PDP商用红粉(Y,Gd)BO3∶Eu3 进行了比较。(Y,Gd)(P,V)O4∶Eu3 的发射主峰在619 nm,比发射主峰为593 nm的(Y,Gd)BO3∶Eu3 色纯度好,是一种很有应用前景的发光材料。 相似文献