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31.
The low for random reals are characterized topologically, as well as in terms of domination of Turing functionals on a set of positive measure.
32.
Torbjörn Kolsrud 《Journal of Theoretical Probability》1989,2(4):399-418
We derive explicit isomorphism formulas between weighted Dirichlet integrals for harmonic functions and boundary Dirichlet forms. Applications yield results on traces of Markov processes and convergence quasieverywhere of harmonic functions. 相似文献
33.
34.
Nanoparticles coated with single stranded DNA have been shown to efficiently hybridize to targets of complementary DNA. This property might be used to implement programmable (or algorithmic) self-assembly to build nanoparticle structures. However, we argue that a DNA coated nanoparticle by itself cannot be used as a programmable self-assembly building block since it does not have directed bonds. A general scheme for assembling and purifying nanoparticle eight-mers with eight geometrically well-directed bonds is presented together with some preliminary experimental work. 相似文献
35.
We compute the entropyh
A
(
U
) in the sense of Connes, Narnhofer and Thirring of Bogoliubov automorphisms
U
of the CAR-algebra with respect to invariant quasifree states
A
with 0A1 having pure point spectrum.Supported in part by a grant from the National Science Foundation 相似文献
36.
Büttiker and Landauer studied scattering off an oscillating rectangular barrier in order to shed light on the time aspects of tunneling. The expression for the traversal time resulting from this study is controversial. In addition, doubts have recently been expressed on technical aspects of their work. In an attempt to clarify these issues, we investigate a generalization of their model to arbitrary oscillating barriers,V(x, t)=V
0(x)+V
1(x)cos t. In the process, we confirm that Büttiker and Landauer's work is technically sound. However, we show, by several examples, that no direct general relation exists between the characteristic frequency of an oscillating barrier and the duration of the tunneling process. For a wide range of realistic parameters this characteristic frequency does not even exist.This paper is dedicated to E. G. D. Cohen. 相似文献
37.
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Journal of Thermal Analysis and Calorimetry - 相似文献
40.
1,2-Dithiolylium salts are thermolysed in the ion source of a mass spectrometer; some salts (group I) undergo thermolysis to give a stable dithiolyl radical where subsequent ionization gives rise to a mass spectrum in which the parent ion corresponds to the dithiolyl ion. The radical may be stabilized before ionization by expulsion of a hydrogen atom to form a neutral dithiole derivative, and then mass spectra exhibit abundant molecular ions corresponding to such dithiole derivatives.Other salts (group II) may expel a proton with formation of a carbene and subsequent dimerization to a tetrathiafulvalene.The thermolytic behaviour of 1,2-dithiolylium salts is compared with their electrochemical behaviour and several analogies are found. 相似文献