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151.
The form of fluctuating hydrodynamic forces has been derived recently [R.B. Jones, Physica 105A (1981) 395] from the stochastic fluid equations of Landau and Lifshitz. We show by general physical arguments as well as by a direct calculation that such forces do not exist in the classical limit. 相似文献
152.
153.
Derek W Robinson 《Journal of Functional Analysis》1977,24(3):280-290
Let U, V be two strongly continuous one-parameter groups of bounded operators on a Banach space with corresponding infinitesimal generators S, T. We prove the following: ∥Ut, ? Vt ∥ = O(t), t → 0, if and only if U = V; ∥Ut ? Vt∥ = O(tα), t → 0; with 0 ? α ? 1, if and only if , where Ω, P, are bounded operators on such that if and only if has a bounded extension to 1. Further results of this nature are inferred for semigroups, reflexive spaces, Hilbert spaces, and von Neumann algebras. 相似文献
154.
The thermodynamic properties of a fluid of hard spheres with dipole and tetrahedral quadrupole moments are investigated using thermodynamic perturbation theory. The drpole-quadrupole coupling is found to be very important at values of the multipole moments that are close to those of water. 相似文献
155.
Dr. Derek A. Waller 《Mathematische Zeitschrift》1972,126(3):243-246
156.
Sodium hydrogen telluride opens many epoxides cleanly by an SN2 process to give telluro-alcohols, which by reduction with nickel boride afford alcohols. An intermediate telluro-alcohol was converted to olefin in high yield by treatment with -toluene-sulphonyl chloride in pyridine. Quaternary ammonium salt are also cleaved efficiently by sodium hydrogen telluride. 相似文献
157.
Giuseppe Distefano Maurizio Guerra Francesco Paolo Colonna Derek Jones Giovanni Consiglio Domenico Spinelli 《Chemical physics》1982,72(3):267-279
The shake-up satellites present in the O1s and N1s energy regions of the XPS spectra of the planar 4-N-piperidyl-nitrobenzene (1) and 2-N-piperidyl-5-nitrothiophen (3), and of the sterically hindered 2-N-piperidyl-nitrobenzene (2), 2-N-piperidyl-3-nitrothiophen (4) and 3-N-piperidyl-2-nitrothiophen (5) and, for comparison, of 2-bromo-3-nitrothiophen (6) have been analyzed with the help of CNDO/S CI calculations. The spectra of the planar derivatives closely resemble these of the related compounds previously analysed, the main satellites deriving from the transition between the highest occupied molecular orbital (HOMO, localized at the donor-ring moiety) towards the lowest unoccupied one (LUMO, localized at the nitro group). Calculations indicate that in the ortho derivatives new relaxation processes are allowed upon N1s/NO2 ionization. In 2, where the angle of rotation θ is closer to 90° than 60°, the NR 2 lone-pair orbital relaxes through space towards the core-ionized N/NO2 atom. In 4 and 5, where 45° ? θ ? 60°, both through-ring and through-space relaxations are present. The assignment of the main N1s/NO2 line in 1 is discussed. 相似文献
158.
We analyze convolution semigroups on a regular measure space which satisfies the local doubling property. We assume the kernels are bounded and symmetric with the characteristic small-time, volume-dependent, singularity. Then, using a weak conservation property, we deduce local lower bounds with a comparable singularity.Applications are given to a wide range of subelliptic and strongly elliptic self-adjoint, or near self-adjoint, operators on Lie groups. 相似文献
159.
Sodium hydrogen telluride reduces .-amine -oxides to the corresponding amines in very high yield, but does not reduce sulphoxides. This reagent also reduces nitrones to .-amines at pH6 and to imines at alkaline pH (10–11). 相似文献
160.
Bert Fraser-Reid Deen B. Tulshian Ray Tsang Derek Lowe Vernon G.S. Box 《Tetrahedron letters》1984,25(41):4579-4582
Structurally equivalent derivatives of pyranosides and cyclohexanes undergo the spiro-Claisen rearrangement with different stereochemical results. A rationalization for the course observed with the pyranosides is suggested, which invokes interaction of the oxygen lone pair with a (developing) electron deficient centre at the spiro carbon. 相似文献