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61.
62.
A study is made of two classes of product topologies on powers of spaces: the general box product topologies, and the general uniform product topologies. Some examples are given and some results are shown about the properties of these general product spaces. This is applied to show that certain spaces of continuous functions with the fine topology are homeomorphic to box product spaces, and certain spaces of continuous functions with the uniform topology are homeomorphic to uniform product spaces.  相似文献   
63.
64.
Simulation results for the diffusive behavior of polymer chain/penetrant systems are analyzed. The attractive range and flexibility of simple chain molecules were varied in order to gauge the effect on dynamics. In all cases, the dimensionless diffusion coefficient, D*, is found to be a smooth, single-valued function of the packing fraction, eta. The functions D*(eta) are found to be power laws with exponents that are sensitive to both chain stiffness and particle type. For a specific system type, the D*'s for both penetrant and chain-center-of-mass extrapolate to zero at the same packing fraction, eta0. This limiting packing fraction is interpreted to be the location of the glass transition, and (eta0-eta), the distance to the glass transition.  相似文献   
65.
    
We consider the motion of convex surfaces with normal speed given by arbitrary strictly monotone, homogeneous degree one functions of the principal curvatures (with no further smoothness assumptions). We prove that such processes deform arbitrary uniformly convex initial surfaces to points in finite time, with spherical limiting shape. This result was known previously only for smooth speeds. The crucial new ingredient in the argument, used to prove convergence of the rescaled surfaces to a sphere without requiring smoothness of the speed, is a surprising hidden divergence form structure in the evolution of certain curvature quantities.  相似文献   
66.
The oxidation of W(110) was studied over a temperature a range of 1000 K to 1600 K at 1 × 10? 6 Torr oxygen. The subsequent oxide structure was then characterized using Low Energy Electron Diffraction (LEED) and Scanning Tunneling Microscopy (STM). It was found that the resulting structure was remarkably similar to that of Mo(110) oxidized under similar conditions. Using the Mo(110) oxide structure as our basis, along with atomic resolution STM images, we have constructed a model for the surface oxide of W(110).  相似文献   
67.
We demonstrate for the six vertex and XXZ model parameterized by = –(q+q-1)/2±1 that when q2N=1 for integer N2 the Bethe's ansatz equations determine only the eigenvectors which are the highest weights of the infinite dimensional sl2 loop algebra symmetry group of the model. Therefore in this case the Bethe's ansatz equations are incomplete and further conditions need to be imposed in order to completely specify the wave function. We discuss how the evaluation parameters of the finite dimensional representations of the sl2 loop algebra can be used to complete this specification.  相似文献   
68.
Employing both null transmission ellipsometry and resonant x-ray diffraction, we confirmed the SmC*FI2-SmC* phase sequence reversal in one liquid crystal compound and specially prepared binary mixtures. This phase sequence reversal was predicted by two recent theoretical advances. Moreover, the temperature range for the SmC*FI2 phase increases significantly in the mixture suggesting that such a phase sequence may exist in other compounds.  相似文献   
69.
There are two critical issues when deriving a macro-scale prediction model starting from a more complete, underlying model. The first is the precise relationship of the fields predicted by the more complete model and the fields predicted by the macro-scale model. The second is the manner of solving a closure problem that is invariably encountered in all such derivations. The understanding that moving averages of the fields predicted by the more complete model are the fields predicted by the macro-scale model is challenged on the grounds that accomplishing a moving average does not eliminate micro-scale variation, it only appears to do so in one representation of the moving average field. The solution of a closure problem by assumption is challenged on the grounds that the most common assumptions are demonstrably invalid, even while leading to prediction models that can provide reasonable estimates of the macro-scale response in some scenarios. In presenting the challenges, it is further shown how a multiresolution analysis by an orthogonal wavelet system provides a framework for both precisely defining macro-scale response fields, i.e., fields from which all micro-scale variation has been eliminated, and presenting a formally exact solution for a precisely described closure problem.  相似文献   
70.
This paper presents experimental evidence, supported by two-dimensional theoretical calculations, that HOONO can be observed in cis-perp (cp) configurations in a pulsed supersonic expansion. The spectral properties (transition frequency, rotational constants, and transition type) of OH overtone transitions originating from a state with predominately cp character are predicted theoretically and compared with those associated with a weak feature at 6996.2 cm(-1) observed experimentally using infrared action spectroscopy. This spectral feature is attributed to HOONO in cp configurations based on its vibrational frequency, rotational band contour, and resultant OH product state distribution.  相似文献   
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