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1.
Electron microscopy is reported for the deposition in this steel; quantitative results are given on the particle size of the phase deposited during a continuous and uninterrupted decomposition. The deposition of the phase occurs in one stage, while the two stages in the variation in the mechanical properties arise from features of the interaction of dislocations with the phase particles. There appears to be only a small energy barrier to the generation of phase particles. Spherulites are formed in regions of interrupted decomposition. The effects of quenching temperature on the deposition mechanism are discussed.Translated from Izvestiya VUZ, Fizika, No. 3, pp. 41–45, March, 1973.  相似文献   

2.
The mixed-valence states of iron atoms in 1, 1-dialkylbiferrocenium cations were found to be affected by the kind of their counter anions. The TCNQ salts showed only an averaged-valence state from 78 K to room temperature, while the triiodide salts showed only a trapped-valence state or a temperature dependent trapped-to-averaged valence state depending on the kind of alkyl group.  相似文献   

3.
4.
A method is described for measuring the relative quantum efficiency of the internal photo-electric effect in semi-conductors by simultaneously measuring the photo-magnetoelectric and photo-conductive effect. The results of measurements on indium antimonide are given. The quantum efficiency begins to increase if the energy of the photon exceeds 0·47 eVat room temperature. The quantum efficiency as a function of the energy of the photon is analysed on the basis of the conception of impact ionization and it is shown that a study of the structure of this curve can supply information on the, band structure of a semi-conductor in the region of high energies of electrons and holes.
. . , 0,47 eV . , .


The authors thank M. Závtová and M. Vantuchová for efficient help with the measurements, K. mirous and V. Vrchovská for preparing the material, E. Antoník for critical remarks and M. Matyá and A. Müller for determining the constants of the material.  相似文献   

5.
LetN, be a von Neumann algebras on a Hilbert space , a common cyclic and separating vector. Assume to be cyclic and also separating forN . Denote by , N , N the modular operators to (, ), (N, ), resp (N , ). Assume now -it N it N for allt 0. (Such type of inclusions ((N U, ) , ) are called half-sided modular.) Then the modular groups it , N ir , N is ,t, r, s generate a unitary representation of the group S1(2, )/Z 2 of positive energy.Another result is related to two half-sided modular inclusions (1 , ) and (2 , ). Under proper conditions the three modular groups it , 1 ir , 2 is ,t, r, s generate the three-dimensional subgroup of O(2, 1) of two commuting translations and the Lorentz transformation.Partly supported by the DFG, SFB 288 Differentialgeometrie und Quantenphysik.  相似文献   

6.
It is shown that if is the generator of a strongly continuous oneparameter group of *-automorphisms of aC*-algebraA and is an unbounded *-derivation ofA with the same domain as , then + is also a generator for all sufficiently small real numbers .  相似文献   

7.
An approximate solution is given of the Schrödinger equation for S-states of an electron in the field of a hole, when the potential energy of the electron has the form — e2/r [1+exp (–qr].
s- , –e2/r [1+exp (–qr].
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8.
The periodic domain structures on unfavourably oriented surface layers of ferromagnetic materials were studied both experimentally and theoretically. The connection between the surface structure and the crystallographic orientation of the crystals was confirmed. All the terms contributing to the total energy of the surface layer were calculated. A general solution of the potential problem is given for arbitrary periodic distribution of the charges.
. . . .
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9.
The losses caused by bremsstahlung during electron-ion and electron-electron collisions in a completely ionized plasma (in Born's approximation) are calculated. The calculation can be carried out analytically for a sufficiently dilute plasma (plasma with infinitely large Debay-Hückel radius). This assumption is satisfied very well by the known classification to actual controlled thermonuclear reaction. A dependence of the formI=an 2. (1+3/2), wherea=0·73×10–16 MeV.cm3.sec–1,n is the number of ions per cm3 and =kT/mc 2, is determined for the amount of energy radiated from 1 cm3 of plasma per sec. In the relativistic temperature regionkTmc 2 the influence of electron-electron collisions begins to predominate. A number of important results concerning radiation losses in relativistic plasma will be published in a later paper.
, ( ). ( -). . , I=an 2. (1+3/2), =0,73. 10–16 MeVcm2s–1,n — =kT/mc 2. kTmc 2 . , .
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10.
We consider the time-inversion operation for relativistic first-order equations that are constructed without the use of multiple representations of the proper Lorentz group. It is proved that the matrix T of the antilinear time-inversion operation is symmetric (antisymmetric) for particles with integral (half-integral) spin. It is shown that for particles with integral (half-integral) spin there exists (does not exist) a linear transformation as a result of which the time-inversion operation reduces to the complex conjugate:(x)= T *(x) where T is a phase factor. A general expression for such a transformation is obtained.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 5–9, December, 1988.  相似文献   

11.
We present a simple and accurate method for characteristic analysis of metal-clad dielectric waveguides and absorptive waveguides. The real partN of the complex modal indexN=N + iN is obtained by solving the corresponding real eigenvalue equation, and the imaginary partN is given by (n/), where= + i is the complex dielectric constant of the absorptive layer, and N/ is obtained by numerical differentiation. The method is straightforward, and the cumbersome solution of complex transcendental equations is completely eliminated. Results for simple structures are in good agreement with those obtained by exact analysis.  相似文献   

12.
The q=2 random cluster model is studied in the context of two mean-field models: the Bethe lattice and the complete graph. For these systems, the critical exponents that are defined in terms of finite clusters have some anomalous values as the critical point is approached from the high-density side, which vindicates the results of earlier studies. In particular, the exponent ~ which characterizes the divergence of the average size of finite clusters is 1/2, and ~, the exponent associated with the length scale of finite clusters, is 1/4. The full collection of exponents indicates an upper critical dimension of 6. The standard mean field exponents of the Ising system are also present in this model (=1/2, =1), which implies, in particular, the presence of two diverging length-scales. Furthermore, the finite cluster exponents are stable to the addition of disorder, which, near the upper critical dimension, may have interesting implications concerning the generality of the disordered system/correlation length bounds.  相似文献   

13.
A dependence of the functional determinant of the operator from the family D() satisfying the condition D()=fD()+D()f on the parameter m2 of infrared regularization is found in the regularization method using a generalized function.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 27–32, June, 1988.  相似文献   

14.
The irreducible bases of the icosahedral double groups I and Ih are explicitly presented in their respective group spaces. Applying these bases to the spin states |j, , we obtain a simple formula for combining the spin states into the symmetry-adapted bases which belong to a given row of given irreducible representations of I and Ih.  相似文献   

15.
We present fermionic sum representations of the characters , s (p, p) of the minimal M(p,p) models for all relatively prime integers p>p for some allowed values of r and s. Our starting point is biomial (q-binomial) identities derived from a truncation of the state counting equations of the XXZ spin 1/2 chain of anisotropy –=–cos((p/p)). We use the Takahashi-Suzuki method to express the allowed values of r (and s) in terms of the continued fraction decomposition of {p/p} (and p/p), where {x} stands for the fractional part of x. These values are, in fact, the dimensions of the Hermitian irreducible representations of SU q- (2) (and SU q+ (2)) with q–=exp(i{p/p}) (and q+=exp(i(p/p))). We also establish the duality relation M(p,p) M(p–p,p) and discuss the action of the Andrews-Bailey transformation in the space of minimal models. Many new identities of the Rogers-Ramanujan type are presented.Dedicated to Prof. Vladimir Rittenberg on his 60th birthday  相似文献   

16.
We discuss the randomly driven systemdx/dt= -W(x) +f(t), wheref(t) is a Gaussian random function or stirring force withf(t)f(t)=2(t–t), andW(x) is of the formgx 1+2. The parameter is a measure of the nonlinearity of the equation. We show how to obtain the correlation functionsx(t)f(t)···x(t( n)) f as a power series in. We obtain three terms in the expansion and show how to use Padé approximants to analytically continue the answer in the variable. By using scaling relations, we show how to get a uniform approximation to the equal-time correlation functions valid for allg and.  相似文献   

17.
. , . Ha . .
Stability of a glow discharge in small currents
Two approximations of the dynamic characteristic of a glow discharge for small currents are derived. In the first approximation only the influence of the rate of rise and decay of charge carriers in the delay process is accounted for. In the second approximation, the influence of the rate of stabilization of the radial electric field in the discharge is added. On the basis of the derived equations the conditions for the simplest stability of the discharge are calculated. A comparison with experiment gives satisfactory results.


. . . . .  相似文献   

18.
A new theory of weak interactions is proposed in which the coupling between theV-A currents j(X) and j(X) is achieved not by vector mesons [by a propagator D c (X-X)], but by a scalar functionR(X – X), a fermion-antifermion loop which plays the role of a unique film joining two different pointsX andX of completely uncoupled space-times (as a result of which the space becomes a continuum). The existence of the actual currents j results from correlations between the two different spinor layers of Dirac layer formation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 25–40, February, 1996.  相似文献   

19.
The theory of double quantum transitions of the M=±2 type, with regard to inhomogeneously broadened spin systems is studied in this paper with the approximation 2T2T3 1. We suppose that the inhomogeneous broadening is formed by an inhomogeneous crystal field. The obtained results describe the magnitude of absorption as a function of the h.f. power and also describe the shape of the absorption curve. It is demonstrated that in inhomogeneously broadened spin systems the absorption curve of double quantum transitions has the form of the difference of two different Lorentz's curves and that at the saturation ( 2T2T1 1) the absorption increases with the cube of the h.f. field intensity. The shape of the curves is expressed by means of phenomenological relaxation constants of the system.
M=±2 2T2T3 1. , - . . , ( 2T2T1 1) . .
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20.
The first observation of the amplified spontaneous emission (ASE) from the RydbergC 1 +( = 0) state of CO is reported. When theC 1 +( = 0) state was populated through the two-photon excitation, infrared radiation near 2.0 m was ejected in forward as well as backward directions along the laser propagation. The assignment as theC 1 +( = 0) B 1 +( = 0) transition was confirmed. Several characteristics of ASE from theC 1 +( = 0) state are presented.This work was supported by the Morino Foundation, a Grant-in-Aid (No. 07640697) and that on Priority-Area-Research Photoreaction Dynamics (No. 07228268) from the Ministry of Education, Science, Sports and Culture, Japan.  相似文献   

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