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291.
Sorption and volume dilation isotherms of semicrystalline poly(4-methyl-1-pentene) (PMP) were measured using CO2 and C3H8 as penetrants, which have sieving diameters of 3.3 and 4.3 Å, respectively. On the other hand, the PMP crystal has a void width of approximately 4 Å as estimated by X-ray diffraction, so it was anticipated that CO2 would be able to sorb into the PMP crystal while C3H8 would not. The data show that C3H8 has a constant partial molar volume of approximately 87 cc/mol, just above the value reported in other rubbery polymers, and are consistent with the hypothesis that the C3H8 molecules are too large to sorb into the PMP crystals. The partial molar volume of CO2 was found to be 39 cc/mol for CO2 weight fractions of up to 0.03. Since the typical partial molar volume of CO2 in rubbery materials is 46 cc/mol, the lower values in this study were attributed to CO2 sorption into crystalline regions of the polymer, which provided no dilation. Application of a two-phase model using the assumption of Henry's law sorption showed that apparently all C3H8 sorption was occurring in the amorphous region but approximately 16% of CO2 sorption occurred in the crystalline regions. © 1996 John Wiley & Sons, Inc. 相似文献
292.
The dynamical characteristics of measurement's uncertainty are investigated under two modes of Dirac field in the Garfinkle–Horowitz–Strominger dilation space‐time. It shows that the Hawking effect induced by the thermal field would result in an expansion of the entropic uncertainty with increasing dilation‐parameter value, as the systemic quantum coherence reduces, reflecting that the Hawking effect could undermine the systemic coherence. Meanwhile, the intrinsic relationship between the uncertainty and quantum coherence is obtained, and it is revealed that the uncertainty's bound is anti‐correlated with the system's quantum coherence. Furthermore, it is illustrated that the systemic mixedness is correlated with the uncertainty to a large extent. Via the information flow theory, various correlations including quantum and classical aspects, which can be used to form a physical explanation on the relationship between the uncertainty and quantum coherence, are also analyzed. Additionally, this investigation is extended to the case of multi‐component measurement, and the applications of the entropic uncertainty relation are illustrated on entanglement criterion and quantum channel capacity. Lastly, it is declared that the measurement uncertainty can be quantitatively suppressed through optimal quantum weak measurement. These investigations might pave an avenue to understand the measurement's uncertainty in the curved space‐time. 相似文献
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We propose a scheme for carpet anti-cloak based on the transformation optics. An anti-cloak layer is designed, which can make the external electromagnetic waves break the carpet cloak shielding. The external electromagnetic waves can be detected under the carpet cloak, while not affecting the role of carpet cloak of stealth. The Jacobian transformation tensor is calculated by numerically solving the Laplace equations with proper boundary condition. Thus, it is possible to design tile anti-cloak layer of irregular shape. The simulation results demonstrate the feasibilities and flexibilities of the structure. Design details and full-wave simulation results are provided. 相似文献
296.
Distributional properties of the order statistics are utilized to characterize distributions of interest. Further, the distributions of one sided random dilation and contraction are obtained and important deductions are discussed. 相似文献
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Dissipative particle dynamics (DPD) was applied to fluid flow in irregular geometries using non‐orthogonal transformation, where an irregular domain is transformed into a simple rectangular domain. Transformation for position and velocity was used to relate the physical and computational domains. This approach was described by simulating fluid flow inside a two‐dimensional convergent–divergent nozzle. The nozzle geometry is controlled by the contraction ratio (CR) in the middle of the channel. The range of Reynolds number and CR, in this paper, was Re = 10hbox??200 and CR = 0.8 and 0.6, respectively. The DPD results were validated against in‐house computational fluid dynamic (CFD) finite volume code based on the stream function vorticity approach. The results revealed an excellent agreement between DPD and CFD. The maximum deviation between the DPD and CFD results was within 2%. Local and average coefficients of friction was calculated and it compared well with the CFD results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
299.
We show that a new attempt by Corda (2016), just like his previous attempt (Corda, 2015) that we had answered before (A.L. Kholmetskii et al., 2015), to reinterpret Mössbauer experiments in a rotating system as a “new, strong and independent proof of the correctness of Einstein’s vision of gravity” is erroneous. In addition, we demonstrate that Corda’s criticism of Yarman–Arik–Kholmetskii gravitation theory (in short YARK), is based on the application of ill-posed logic; thus rendering his claims against YARK as unfounded. 相似文献
300.
Sarnak's Disjointness Conjecture states that the Möbius function is disjoint with any zeroentropy flow. This note establishes this conjecture, with a rate, for Furstenberg's irregular flows on the infinite-dimensional torus. 相似文献