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1.
Quantitative study of effective parameters of chiral composite material   总被引:1,自引:0,他引:1  
The effective parameters of chiral composite are studied quantitatively using a model, say, chiral spheres immersed in a nonchiral host medium. The effects of the volume fraction of the chiral phase, f, the parameters of the host medium, and , on the effective properties of the composite are calculated. As an example, the microwave reflection properties of a chiral composite coating is compared with that of its host medium coating.  相似文献   

2.
NaCl Cd [10]. , NaCl Ni , .
Absorption and dispersion on NaCl Ni crystals
The results of measuring the absorption and dispersion of light on NaCl Cd crystals were compared with the X-ray diffraction measurements by Toman [10]. The comparison showed that under certain conditions micro-regions of segregated impurities are produced in NaCl Ni crystals, apparent in an increased dispersion of light in the ultra-violet region.
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3.
That millimeter wave propagation through a chiral medium of human trunk has been discussed by obtaining the electromagnetic filed, absorbent power, specific absorption rate, temperature field and their distribution in a human trunk model with plane strati calate homogeneous tissues under a normal incidence plane wave. The chiral medium is described electromagnetically by the constitutive relationsD=E+B andB=H+E. The constants, and ate real and have values that are fixed by the size, the shape, and the spatial distribution of the elements that collectively compose the medium. Also, the principle of thermal therapeutics for millimeter wave is discussed preliminaryly.  相似文献   

4.
In a nongeometrical interpretation of gravity,the metric g(x) = + (x)is interpreted as an effective metric, whereas(x) is interpreted as afundamental gravitational field, propagated in spacetime which isactually flat. Some advantages and disadvantages of suchan interpretation are discussed. The main advantage isa natural resolution of the flatness problem.  相似文献   

5.
, , . , I. . . , .
Betatron oscillations in an accelerator with a general field. II
In the second part of the theory of an accelerator with a generalized field the author solves the dynamics of particles in a stationary approximation (without acceleration). The trajectories of the particles in the neigbourhood of the equilibrium orbit are related to it as betatron oscillations. An analysis of betatron oscillations includes the region of stability determined by means of Routh-Hurwitz criterion, damping, resonance effects and field perturbations. A general matrix method is presented permiting the inclusion of all the focusing structures used in accelerators.
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6.
A misunderstanding persists between Stuart and me, which I do my best to clarify. Bayesian inverse subjectivities versus relativistic covariance and physical intersubjectivity are discussed. A joint number of chances formalism taking care of the propagation of the probability of causes is proposed.  相似文献   

7.
The contact process is a model of spread of an infectious disease. Combining with the result of ref. 1, we prove that the critical exponents take on the mean-field values for sufficiently high dimensional nearest-neighbor models and for sufficiently spread-out models with d>4:() c as c and ()( c)–1 as c, where () and () are the spread probability and the susceptibility of the infection respectively, and c is the critical infection rate. Our results imply that the upper critical dimension for the contact process is at most 4.  相似文献   

8.
It is shown that by solving the linear integral Agranovi-Marenko equation for potentials-scattering one can obtain: 1) in the simplest case, when the scattering matrixS has one redundant pole in the upper half-plane of the impulse, the Bargmann potentials; 2) if theS-matrix hasn redundant poles — the equations, which Petras derived fors-scattering using an adapted and simplified Bargmann method; 3) if theS-matrix is discontinuous on a certain interval — the non-relativistic Noyes-Wong equation and 4) further relations — for combinations of isolated poles and discontinuities of theS-matrix on intervals. The former equations can be obtained from the latter as specific cases. In the discussion, the relation between the value of the residuum of theS-matrix in the redundant poles and the number of bound states is shown and the solution of the inverse problem for a band spectrum is sketched.
, - s-, : 1) , S — . 2) , S-n — , , s-. 3) S- — . 4) — S- . . S- .
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9.
The self-averaging properties of the conductanceg are explored in random resistor networks (RRN) with a broad distribution of bond strengthsP(g)g –1. The RRN problem is cast in terms of simple combinations of random variables on hierarchical lattices. Distributions of equivalent conductances are estimated numerically on hierarchical lattices as a function of sizeL and the distribution tail strength parameter . For networks above the percolation threshold, convergence to a Gaussian basin is always the case, except in the limit 0. Adisorder length D is identified, beyond which the system is effectively homogeneous. This length scale diverges as Dµ–v ( is the regular percolation correlation length exponent) when the microscopic distribution of conductors is exponentially wide (0). This implies that exactly the same critical behavior can be induced by geometrical disorder and by strong bond disorder with the bond occupation probabilityp. We find that only lattices at the percolation threshold have renormalized probability distributions in aLevy-like basin. At the percolation threshold the disorder length diverges at a critical tail strength µc as µ––z withz3.2±0.1, a new exponent.Critical path analysis is used in a generalized form to give the macroscopic conductance in the case of lattices abovep c.  相似文献   

10.
The fundamental concepts of the theory of dislocations are given in an exact way and some theorems are proved.
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In conclusion the author would like to thank Professor M. Valouch and Professor L. Zachoval for the interest they took in this work and for remarks and advice which helped to improve it.  相似文献   

11.
We give an explicit L 2-representation of chiral charged fermions using the Hardy–Lebesgue octant decomposition. In the pure case such a representation has already been used by M. Sato in holonomic field theory. We study both pure and mixed cases. In the compact case, we rigorously define unsmeared chiral charged fermion operators inside the unit circle. Using chiral fermions, we orient our findings towards a functional analytic study of vertex algebras as one-dimensional quantum field theory.  相似文献   

12.
A study is made of the Shockley surface states in a linear chain of equal atoms, joined by alternately strong bonds. If the simple MO LCAO method is used, which considers the exchange integrals between nearest neighbours and next nearest neighbours, we get the surface states for a semi-infinite chain if the stronger bond is interrupted. The connection between Shockley and Tamm surface states is shown and the hypothesis is put forward that the condition for the existence of Shockley surface states has a generally simple physical interpretation, the validity of which is proved on the models of a semi-infinite crystal studied up to now.
, . MO LCAO, , , . , , , .
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13.
- .
On the Vavilov-erenkov radiation in uniaxial crystals
An investigation is made of the Vavilov-erenkov radiation energy in uniaxial magnetic crystals and in uniaxial crystals with double anisotropy.


: - , .

. . . .  相似文献   

14.
The paper points to the possibility of describing the properties of recombination centres by means of the quantitiesc p/c n ande n/e p, in contrast to the existing method based mainly on the so-called energy position of recombination levels. The proposal is supported by a simple statistical analysis and by experimental material and has some advantages over the method used hitherto.
c p/cn e n/ep , . .
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15.
[1] t B , t B . , t B , . .
A note on the theory of the successive production of moving striations in the plasma of inert gases
Approximate expressions are derived on the basis of Pekárek's theoretical paper [1] for the period of the maximum tB of a wave packet produced by the passage of a wave of stratification before the aperture of a photomultiplier, and for its time width in the half-height tB. The relaxation time of a wave of stratification, following from the theory [1], can thus be calculated by means of the experimentally measured velocity of motion of the maximum of a wave packet u and its width tB. The calculation is supplemented by numerical data on the magnitude of errors committed by using approximate expressions.
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16.
17.
Energy levels and electromagnetic properties of fluorin isotopes in the Nilsson's model with Coriolis mixing are investigated. Position of the F19 levels is satisfactorily explained up to the energy of 4·5 MeV. Concerning the F21 it seems that the shell model will better correspond to the F21 nucleus.

. , .  相似文献   

18.
19.
20.
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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