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51.
For any locally compact groupG, we show that any locally tight homomorphism from a real directed semigroup intoM 1 (G) (semigroup of probability measures onG) has a shift which extends to a continuous one-parameter semigroup. IfG is ap-adic algebraic group then the above holds even iff is not locally tight. These results are applied to give sufficient conditions for embeddability of some translate of limits of sequences of the form {v n kn } and M 1 (G) such that ()= M , for somek>1 and AutG (cf. Theorems 2.1, 2.4, 3.7).  相似文献   
52.
The Banach algebra generated by one-dimensional linear singular integral operators with matrix valued piecewise continuous coefficients in the spaceL p (,) with an arbitrary weight is studied. The contour consists of a finite number of closed curves and open arcs with satisfy the Carleson condition. The contour may have a finite number of points of selfintersection. The symbol calculus in this algebra is the main result of the paper.  相似文献   
53.
We found the field structure, exact dispersion relations and power flow ofp-polarized nonlinear guided and surface waves travelling along a three-component layered structure consisting of a film of thicknessd with dielectric constant b bounded at the negativez-side by a linear medium with dielectric constant a and at the positivez-side by a nonlinear uniaxial substrate characterized by the diagonal dielectric tensor 11 = 22 = + (|E 1|2 + |E 2|2), 33 = , <0 (self-defocusing medium),E 1 andE 2 being the components of the electric field in thex andy-direction, respectively. It is shown that for sufficiently smalld/ (: wavelength) the nonlinear wave may exist only at power flows exceeding some certain minimum values. For sufficiently larged/ to some values of the power flow there correspond two distinct values of the propagation constant. In this case with increasing of the power flow the number of waveguide modes is decreasing and for higher-order modes the film-waveguide exhibits an optical-power limiter from the above behaviour.  相似文献   
54.
维生素B12缺乏致神经损害临床分析   总被引:2,自引:0,他引:2  
维生素B12缺乏多继发于胃肠道外科手术后、贫血及其它内科疾病,其引起的神经系统损害临床表现多样,主要为周围神经损害及亚急性联合变性。测定维生素B1:值、查肌电图等可明确诊断。补充维生素B12治疗有效。  相似文献   
55.
A permutation set (M, I) consisting of a setM and a set of permutations ofM, is calledsymmetric, if for any two permutations, the existence of anx M with (x) (x) and –1 (x) = –1 (x) implies –1 = –1 , andsharply 3-transitive, if for any two triples (x 1,x 2,x 3), (y 1,y 2,y 3) M 3 with|{x 1,x 2,x 3 }| = |{y 1,y 2,y 3 }| = 3 there is exactly one permutation with(x 1) =y 1,(x 2) =y 2,(x 3) =y 3. The following theorem will be proved.THEOREM.Let (M, ) be a sharply 3-transitive symmetric permutation set with |M|3, such that contains the identity. Then is a group and there is a commutative field K such that and the projective linear group PGL(2, K) are isomorphic.  相似文献   
56.
When Fe3+ ions are substituted by aluminum or chromium on magnetite octahedral sites, the ir spectrum shows the conversion of an inverse spinel to a normal spinel. Both broad bands of magnetite are gradually replaced by the four characteristic bands of normal spinels II–III. They are also observed for solid solutions, FeCr2O4FeAl2O4, with, however, a further band at 780 cm?1 which may be assigned to Al3+ ions on tetrahedral sites. Low-temperature (<400°C) oxidation of these compounds whose sizes are less than 2000 Å results in lacunar spinels III–III. The ir spectrum of these solids is characterized by two absorption bands (as for inverse spinels II–III) except for compounds close to pure γFe2O3 in which an order of vacancies could be put in evidence.  相似文献   
57.
Weakly bound linear and bent dimers, FH—X (where X = CO, OC, CNH, NCH, N2O and ON2), are investigated using the DFT B3LYP and ab initio MP2 methods with the same basis sets (6–311++G(3df,2pd)). The strengths of the H—C or H—N H‐bonds in dimers FH—CO, FH—CNH, and FH—N2O are compared with those of the H—O or H—N H‐bonds in dimers FH—OC, FH—NCH, and FH—ON2. The results obtained for the H‐bond distances, the elongation effect of the HF bond, the red shift of the HF stretching frequency, and the energy difference between the dimer and the charge transfer reveal that the H‐bonds of the first group of dimers are stronger than those of the second. The Gibbs energies calculated for the six dimer formations indicate that the weakly bound dimers are unstable at room temperature (T = 298 K) (FH—X's → FH + X's, ΔG < 0).  相似文献   
58.
The structures of B32 and B32H2–32 with Ih symmetry have been investigated by means of ab initio calculations at STO-3G level. The relationship between molecular orbitals of them has been analyzed and their bonding properties have been discussed. Then the possibility of their existence, as well as the similarity and difference between B32 (B32H2–32) and C60 (C60H60) have been inferred.  相似文献   
59.
Summary Nearfields of rank 2 over their kernel which are not Dickson nearfields have recently been constructed by H. Zassenhaus. Here it is shown that KT-nearfields of rank 2 over their kernels and of characteristic 2 are necessarily Dickson nearfields which are coupled to quadratic field extensions and their Dickson group is isomorphic to 2. Using results of Gröger one obtains all KT-nearfields of rank 2 over the field of rational numbers.  相似文献   
60.
Summary LetX be a real vector space,D a convex subset ofX and (Y, K) an order complete ordered vector space. The following sandwich theorem holds: Iff: D Y is midconvex,g: D Y {– } is midconcave andg f onD, then there exists a Jensen mappingh: D Y {– } such thatg h f onD. Using this theorem we show that a mappingf: D Y is midconvex if and only if it has Jensen support at every point ofD. Moreover, ifX is a Baire topological vector space and (Y, K) is an ordered topological vector space satisfying some additional conditions, then a mappingf: D Y is continuous whenever it has continuous Jensen support at every point ofD. As an application of these results we obtain the equality of some set-classes connected with additive and midconvex operators.Dedicated to the memory of Alexander M. Ostrowski on the occasion of the 100th anniversary of his birth  相似文献   
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