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1.
The specific electrical resistance , mean magnetic moment of an atom of the alloy, and the anomalous Hall (Rs) and Nernst-Ettinghausen (Qs) constants of ordered alloys Ni3(Fe, Ti) and Ni3(Mn, Ti) are investigated. It is suggested that there is an additional degree of delocalization of the 3d electrons of the system Ni3(Mn, Ti) and increase in the degree of localization of 3d electrons of the system Ni3(Fe, Ti) with small additions of Ti, with increase in the long-range-order parameter. A model of the electronic structure of the given alloys is discussed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 56–59, October, 1981. 相似文献
2.
The ordinary Hall constant Ro of quenched Ni3(Fe, Ti) and Ni3(Mn, Ti) alloys was measured. The number of 4s and 3d electrons per atom was calculated on the basis of a four-band model. At low Ti concentrations in Ni3(Fe, Ti) the contribution of 3d holes to Ro is negligible, but at high concentrations it is significant. The contribution of 3d holes to Ro for Ni3(Mn, Ti) is considerable, and for Ni3Mn and Ni3(Mn +9.8% Ti) it is dominant. It is concluded that the changes in band energy of the bond between Ni and Ti in the considered systems are of a different nature.Deceased.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 12–14, May, 1981. 相似文献
3.
In this work we used x-ray structural analysis to investigate the martensitic transformations (MTs)B2R andRB19 in Ti(Ni, Fe) alloys containing 1, 2.5, 4, 5 at. % Fe, and the effect of heat treatment on the MT temperatures and sequence. In the majority of cases, it was found that the MTB2R proceeds through a two-phase region (+R). Heat treatment leads to a narrowing of the temperature interval of the existence of the two-phase region, weakly affects the onset temperatures of the MTsB2R TR andRB19 Ms, and sharply increases the temperature-of the end of the MT Me. The existence of the two-phase region is related to the two MT channelsB2R andB2B19 initially intrinsic to the allovs of the given compositions.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 19–22, December, 1989. 相似文献
4.
Hall effect in the ternary ordered alloys Ni3(Mn,Fe) and Ni3(Mn,Co) 1. Disordered solution solutions
The normal and anomalous Hall constants R0 and Rs, respectively, and the resistivity have been measured for the quasibinary alloys Ni3Mn-Ni3Fe and Ni3Mn-Ni3Co. The results imply that in ternary alloys of Ni3Mn containing slight Fe and Co impurities the hole regions of the Fermi surface make an important contribution to R0 and that the primary scattering mechanism for the carriers corresponding to the anomalous Hall current in the alloys with Fe at room temperature is phonon scattering. It is concluded that the Fermi surface of the Ni3Mn-Ni3Fe alloys is closed.Translated from Izvestiya VUZ. Fizika, No. 3, pp. 21–29, March, 1970. 相似文献
5.
Nils A. Törnqvist 《Zeitschrift fur Physik C Particles and Fields》1994,61(3):525-537
A systematic study of possible deuteronlike twomeson bound states,deusons, is presented. Previous arguments that many such bound states may exist are elaborated with detailed arguments and numerical calculations including, in particular, the tensor potential. This tensor potential which is crucial for the deuteron binding is shown to be very important also in the mesonic case. Especially, in the pseudoscalar3
P
0 pseudoscalar-vector
and vector-vector
channels the important observation is made that the centrifugal barrier from theP-wave can be overcome by the 1/r
2 and 1/r
3 terms of the tensor potential. In the heavy meson sector one-pion exchange alone is strong enough to form at least deuteronlike
and
composites bound by approximately 50 MeV. Composites of
and
states bound by pion exchange alone are expected near the thresholds, while in the light meson sector one generally needs some additional short range attraction to form bound states. The quantum numbers of these states areI=0, andJ
PC=0–+, 1++ for the
states andI=0,J
PC=0++, O–+, 1+– and 2++ for the
composites. In
the states:
b
(10545),
b1(10562) are predicted and in
, one finds the states:
b
(10590),
bQ
(10582),h
b(10608),
b2(10602). Near the
threshold the states:
c
(3870),
c0(3870) are predicted, and near the
threshold one finds the states:
b0(4015),
c
(4015),h
c(4015),
c2(4015). Within the light meson sector pion exchange gives strong attraction for
and
systems with quantum numbers where the best non-
candidates exist, although pion exchange alone is not strong enough to support such bound states. Thus, although one cannot conclude with certainty it to be the case, this fact does favour the picture that the (1440) and thef
1 (1420) are mainly
composites and thef
0(1710) mainly a
bound state, while thef
0(1515) andf
2(1520) could be predominantly
composites. If the predicted
and
states are found, these would support this interpretation of the light states. In channels with exotic flavour orCP quantum numbers pion exchange is generally repulsive or quite weak. Therefore one does not expect that such deuteronlike bound states exist, althoughB*B* may be an exception. 相似文献
6.
Given a simple, simply laced, complex Lie algebra
corresponding to the Lie group G, let
be thesubalgebra generated by the positive roots. In this Letter we construct aBV algebra
whose underlying graded commutative algebra is given by the cohomology, with respect to
, of the algebra of regular functions on G with values in
. We conjecture that
describes the algebra of allphysical (i.e., BRST invariant) operators of the noncritical
string. The conjecture is verified in the two explicitly known cases,
2 (the Virasoro string) and
3 (the
string). 相似文献
7.
We have examined the influence of parametric noise on the solution behavioru(t, x) of a nonlinear initial value() problem arising in cell kinetics. In terms of ensemble statistics, the eventual limiting solution mean
and variance
are well-characterized functions of the noise statistics, and
and
depend on . When noise is continuously present along the trajectory,
and
are independent of the noise statistics and . However, in their evolution toward
and
, both
u
(t, x) and
u
2
(t, x) depend on the noise and. 相似文献
8.
C. Quesne 《International Journal of Theoretical Physics》1999,38(7):1905-1923
GLh(n) ×GLh(m)-covariant (hh)-bosonic[or (hh)-fermionic] algebras
are built in terms of thecorresponding Rh and
-matrices by contracting theGLq(n) ×
-covariant q-bosonic (or q-fermionic) algebras
, = 1, 2.When using a basis of
wherein theannihilation operators are contragredient to thecreation ones, this contraction procedure can be carried out for any n, m values. Whenemploying instead a basis wherein the annihilationoperators, like the creation ones, are irreducibletensor operators with respect to the dual quantumalgebra Uq(gl(n))
, a contraction limit only exists forn, m {1, 2, 4, 6, . . .}. For n = 2, m = 1, andn = m = 2, the resulting relations can be expressed interms of coupled (anti)commutators (as in the classical case), by usingUh(sl(2)) [instead of s1(2)] Clebsch-Gordancoefficients. Some Uh(sl(2)) rank-1/2irreducible tensor operators recently constructed byAizawa are shown to provide a realization of
(2, 1). 相似文献
9.
We examine the BRS cohomology of chiral matter inN=1,D=4 supersymmetry to determine a general form of composite superfield operators which can suffer from supersymmetry anomalies. Composite superfield operators (a, b) are products of the elementary chiral superfieldsS and
and the derivative operatorsD
,
and
. Such superfields (a, b) can be chosen to have a symmetrized undotted indices
i
and b symmetrized dotted indices
. The result derived here is that each composite superfield (a,b) is subject to potential supersymmetry anomalies ifa–b is an odd number, which means that (a,b) is a fermionic superfield. 相似文献
10.
Ulf Ottoson 《Communications in Mathematical Physics》1968,10(2):114-131
All inequivalent continuous unitary irreducible representations ofS U(N, 1) (N2) have been determined and classified. The matrix elements of the infinitesimal generators realized on a certain Hilbert space have been derived. Representations of the groups
,S U(N, 1)/Z
N+1,
andU(N, 1) are classified in a similar manner. 相似文献
11.
Nils A. Törnqvist 《Zeitschrift fur Physik C Particles and Fields》1995,68(4):647-660
It is shown that one can fit the available data on thea
o(980),f
o(1300) andK
o
*
(1430) mesons as a distorted 0++
nonet using very few (5–6) parameters and an improved version of the unitarized quark model. This includes all light two-pseudoscalar thresholds, constraints from Adler zeroes, flavour symmetric couplings, unitarity and physically acceptable analyticity. The parameters include a bare
or
mass, an over-all coupling constant, a cutoff and a strange quark mass of 100 MeV, which is in accord with expectations from the quark model. It is found that in particular for thea
0(980) andf
0(980) the
component, in the wave function is large, i.e., for a large fraction of the time the
state is transformed into a virtual
pair. This
component, together with a similar component of for thea
0(980), and , and components for thef
0(980), causes the substantial shift to a lower mass than what is naively expected from the
component alone. Mass, width and mixing parameters, including sheet and pole positions, of the four resonances are given, with a detailed pedagogical discussion of their meaning. 相似文献
12.
André Gleyzal 《Foundations of Physics》1976,6(3):299-303
An analytic gravitational fieldZ
(Z
y
) is shown to include electromagnetic phenomena. In an almost flat and almost static complex geometryds
2
=zdzdz of four complex variables z=t, x, y, x the field equationsR
Rz
= –(U
U
– Z
) imply the conventional equations of motion and the conventional electromagnetic field equations to first order if =(Z
v) and =(z
) are expressed in terms of the conventional mass density function
, the conventional charge density function
, and a pressurep as follows:
v=const=p/c
2–10–29 gm/cm3. 相似文献
13.
We obtain partial results on the conjecture that for the almost Mathieu operator at irrational frequency, , the measure of the spectrum,S(, , )=|4–2|. For ||2 we show that if n is rational and
irrational, then
.Dedicated to Res Jost and Arthur WightmanResearch partially supported by U.S. NSF grant number DMS-8801918 and by BSF under grant number 88-00325 相似文献
14.
In the framework of the heavy-quark effective theory, theO
(
O(QCD)) corrections are estimated in the test of factorization hypothesis forB-meson nonleptonic decays proposed by Bjorken. Similar calculations are also carried out for
b
nonleptonic decays. The effects of these corrections on the estimate of theD
s
-meson decay constant are discussed. 相似文献
15.
We consider SU
q
(2) covariant
-matrices for the reducible3 1 representation. There are three solutions to the Yang-Baxter equation. They coincide with the previously known
-matrices for SO
q
(3) and SO
q
(3, 1). Also, they are the three
-matrices which can be constructed by using four different SU
q
(2) doublets. Only two of the three
-matrices allow a differential structure on the reducible four-dimensional quantum space. 相似文献
16.
M.J. Prandolini W.D. Hutchison J. Leib D.H. Chaplin G.J. Bowden 《Hyperfine Interactions》1998,116(1-4):83-89
NMRON studies for the
54Mn transitions in antiferromagnetic MnBr2
4H2O, in the millikelvin regime, are presented and discussed. New values are given for (i) the sum of the effective molecular exchange and magnetic anisotropy fields acting on the Mn2+ ions,
=2.23(2) T, and (ii) the magnetic dipole hyperfine splitting, A=-201.99(1) MHz, electric quadrupole hyperfine splitting P=0.049(8) MHz and pseudoquadrupole splitting
=1.63(2) MHz for the 54Mn nuclei. 相似文献
17.
N. A. Koneva A. D. Korotaev M. A. Bol'shanina S. G. Shtein 《Russian Physics Journal》1967,10(1):19-22
Yield point, hardening factor, and elastic modulus are reported as functions of quenching and test temperatures for the alloys Ni3(Fe + 3 at% Al), Ni3(Fe + 3 at% Mn). A maximum is found in the mechanical properties near the critical temperature Tcr; this does not occur for alloys in the disordered state. The deformation aging under load is examined near this maximum and at 200 ° C. A range of linear hardening occurs up to e of 15–18% in ordered alloys, which is replaced by a range of decreasing hardening coefficient at higher . The results are discussed by reference to earlier ones for Ni3Fe, Ni3(FeCr). Ni3(FeMo). 相似文献
18.
The approach to isospectral Hamiltonian flow introduced in part I is further developed to include integration of flows with singular spectral curves. The flow on finite dimensional Ad*-invariant Poisson submanifolds of the dual
of the positive part of the loop algebra
is obtained through a generalization of the standard method of linearization on the Jacobi variety of the invariant spectral curveS. These curves are embedded in the total space of a line bundleTP
1(C), allowing an explicit analysis of singularities arising from the structure of the image of a moment map
from the space of rank-r deformations of a fixedN×N matrixA. It is shown how the linear flow of line bundles
over a suitably desingularized curve
may be used to determine both the flow of matricial polynomialsL() and the Hamiltonian flow in the spaceM
N,r×MN,r in terms of -functions. The resulting flows are proved to be completely integrable. The reductions to subalgebras developed in part I are shown to correspond to invariance of the spectral curves and line bundles
under certain linear or anti-linear involutions. The integration of two examples from part I is given to illustrate the method: the Rosochatius system, and the CNLS (coupled non-linear Schrödinger) equation.Research supported in part by the Natural Sciences and Engineering Research Council of Canada and by U.S. Army grant DAA L03-87-K-0110 相似文献
19.
We study the initial value problem for the two-dimensional nonlinear nonlocal Schrödinger equations i ut + u = N(v), (t, x, y) R3, u(0, x, y) = u0(x, y), (x, y) R2 (A), where the Laplacian = 2
x + 2
y, the solution u is a complex valued function, the nonlinear term N = N1 + N2 consists of the local nonlinear part N1(v) which is cubic with respect to the vector v=(u,ux,uy,\overline{u},\overline{u}_{x},\overline{u}_{y}) in the neighborhood of the origin, and the nonlocal nonlinear part N2(v) =(v, – 1
x Kx(v)) + (v, – 1
y Ky(v)), where (, ) denotes the inner product,
and the vectors Kx (C4(C6; C))6 and Ky (C4(C6; C))6 are quadratic with respect to the vector v in the neighborhood of the origin. We assume that the components K(2)
x = K(4)
x 0, K(3)
y = K(6)
y 0. In particular, Equation (A) includes two physical examples appearing in fluid dynamics. The elliptic–hyperbolic Davey–Stewartson system can be reduced to Equation (A) with
, and all the rest components of the vectors Kx and Ky are equal to zero. The elliptic–hyperbolic Ishimori system is involved in Equation (A), when
, and
. Our purpose in this paper is to prove the local existence in time of small solutions to the Cauchy problem (A) in the usual Sobolev space, and the global-in-time existence of small solutions to the Cauchy problem (A) in the weighted Sobolev space under some conditions on the complex conjugate structure of the nonlinear terms, namely if N(ei v) = ei N(v) for all R. 相似文献
20.
The tensor product of two supersingleton representations
n of the Lie superalgebraosp (1, 2n) is studied forn2. The main results are as follows: (a) anticommutators and commutators of the odd generators in
n
n form a skew-symmetric representation of the Lie algebrau(n, n); (b) simple explicit form of all irreducible components of
n
n, which are labelled by a single parameterJ=0, 1, ..., has been found. Each of them is a*-representation ofosp (1, 2n) for which assertion (a) is valid. The dimension of its vacuum subspace equals
, i.e., the nondegenerate vacuum occurs for J=0 only. Basic property of this family of irreducible*-representations of osp(1, 2n) are analogous to those of massless representations of osp(1, 4).Dedicated to Academician Václav Votruba on the occasion of his eightieth birthday. 相似文献