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981.
Eric Slud 《Probability Theory and Related Fields》1978,42(4):341-352
Summary For rank-discounted partial sums and averages, forward and backward invariance principles are established through the use of the Bahadur-Kiefer representation of sample quantiles and the Kiefer process approximation of the sample distributions.Work supported by the Air Force Office of Scientific Research, USAF, AFSC, Grant No. AFOSR 74-2736 相似文献
982.
983.
Summary.
In this paper we perform an asymptotic study of the Maxwell equations with
respect to the small parameter where is the characteristic
velocity associated with the physical problem and is the speed of light.
This enables us to derive the quasistatic and Darwin models as respectively
first and second order approximations of the Maxwell equations. Moreover,
an interpretation of the obtained variational formulations gives us the
appropriate boundary conditions for these models.
Received May 18, 1995 相似文献
984.
The Casimir energy of the gravitational field in Kaluza-Klein theories is investigated. The mathematical techniques needed to compute the contribution of a single graviton loop to the quantum effective potential on a background manifold of (Minkowski space) ? (N-sphere) are developed. In these computations the cosmological constant plays a dynamical role, acting like a mass for the graviton. The numerical work for the case N = 1 is done explicitly, and a solution to the one-loop corrected equations of motion is found, although it is not stable. The possibility of an imaginary part to the effective potential for N > 1 is noted, and its existence is attributed to tachyonic terms in the mode sum. 相似文献
985.
Diisopropyl fluorophosphate (DFP), a volatile highly toxic enzyme inhibitor, in buffer (pH 3, pH 5, pH 7, pH 9, pH 11, Hank’s,
Dulbecco’s, PBS, TBE, and HEPES) or water (10 mM), in DMF solution (200 mM), and bulk quantities can be degraded by adding
1M NaOH. The DFP was completely degraded, as determined by enzymatic assay, and the final reaction mixtures were not mutagenic. 相似文献
986.
Pierre-Jean Nacher Eric Stoltz Geneviève Tastevin 《Czechoslovak Journal of Physics》1996,46(6):3025-3032
Laser optical pumping in low magnetic field provides very high nuclear polarizations in gaseous helium mixtures, and is used to prepare polarized liquid. Wall relaxation in glass cells is effiently reduced using cesium coatings, and bulk longitudinal relaxation times are measured. In highly magnetized samples, dipolar fields control the spin dynamics in anisotropic volumes and weak external magnetic field inhomogeneities. Long lived magnetostatic modes are observed by pulsed NMR. Detailed analysis of their frequency and damping gives information on magnetization density and spin diffusion coefficient in polarized mixtures. Experiments are performed above 0.2 K on mixtures with3He concentrations of order a few percents or larger. When phase separation occurs, the3He-rich phase retains a high polarization. 相似文献
987.
Pentaammineruthenium complexes bridged by 2,3-dicyanopyrazine and 2,3-dicyano-5, 6-dimethylpyrazine have been prepared and characterized. The bridging ligand binds to the metal atoms through the cyano nitrogen. Complexes can be prepared in the +4 and +6 oxidation states but the mixed-valence, +5, state is not observed experimentally, unlike the previously prepared 1,2-dicyanobenzene dimer which does have a stable +5 state. A simple electronic model is constructed from the spectroscopic data and is used to show that the electronic perturbations caused by the uncomplexed nitrogen atoms in the pyrazine ring are sufficient to drive the disproportionation reaction of the +5 state. 相似文献
988.
The Schrödinger equation for a spin-0 particle in the field of a dyon is obtained by dimensional reduction of the four-dimensional harmonic oscillator; the reduction is effected by imposing an equivariance condition on the wave functions of the latter system. This geometrical construction allows for a simple derivation of the SO(4, 2) spectrum symmetry of the dyon system. A supermultiplet of one and two spin-0 particles in a Coulomb potential is demonstrated to possess an N = 2 conformal supersymmetry through a generalization of the same method. The states and wave functions for these systems can be obtained from the representation theory of the corresponding symmetry algebras. A particular case for which this approach provides a complete group theoretical analysis is that of the Pauli equation for a particle in the field of a dyon. 相似文献
989.
990.
Nicolas Popoff Jeff Espinas Eric Gour Olivier Boyron Erwan Le Roux Jean‐Marie Basset Rgis M. Gauvin Aimery De Mallmann Mostafa Taoufik 《Macromolecular rapid communications》2011,32(23):1921-1924
Silica‐supported titanium(IV) chloride is readily reduced by Mashima and co‐workers' reagent (1‐methyl‐3,6‐bis(trimethylsilyl)‐1,4‐cyclohexadiene) to afford materials active in ethylene polymerisation without need of aluminum alkyl cocatalyst. 相似文献