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71.
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As a result of environmental concern, there is an increasing interest in the development of biodegradable polymers for packaging with suitable properties, as an alternative to the synthetic petroleum‐based polymers. However, such biodegradable polymers are prevented for use in wide industrial and commercial packaging because of their limited gas and vapor barrier properties. This obstacle urges innovative strategies to achieve enhanced gas barrier properties using “bio‐layering” technologies. Whey protein isolate (WPI), a by‐product of the cheese industry, has quite promising properties for packaging purposes. It possesses good oxygen, aroma, and oil barrier properties; however, its permeability to water vapor is high. In this study, several WPI coatings were obtained, adding polyvinyl alcohol and pectin to improve the coated film properties; in addition, nanoclays were used to improve water vapor barrier properties. Comparison of neat poly (lactic acid) film versus poly (lactic acid) coated with WPI presented advantage of the later: improvement of about 90% in the oxygen barrier properties and about 27% in the water vapor barrier properties. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
73.
In this paper we present an analytic expression for the Lorentz integral transform of an arbitrary response function expressed
as a polynomial times a decaying exponent. The resulting expression is applied to the inversion problem of the Lorentz integral
transform, simplifying the inversion procedure and improving the accuracy of the procedure. 相似文献
74.
75.
Simon Halvdansson Jan-Fredrik Olsen Nir Sochen Ron Levie 《Mathematische Nachrichten》2023,296(3):1156-1172
Continuous wavelet design is the endeavor to construct mother wavelets with desirable properties for the continuous wavelet transform (CWT). One class of methods for choosing a mother wavelet involves minimizing a functional, called the wavelet uncertainty functional. Recently, two new wavelet uncertainty functionals were derived from theoretical foundations. In both approaches, the uncertainty of a mother wavelet describes its concentration, or accuracy, as a time-scale probe. While an uncertainty minimizing mother wavelet can be proven to have desirable localization properties, the existence of such a minimizer was never studied. In this paper, we prove the existence of minimizers for the two uncertainty functionals. 相似文献
76.
Itzhak Halevy Shlomo Haroush Yosef Eisen Ido Silberman Dany Moreno Amir Hen Mike L. Winterrose Sanjit Ghose Zhiqiang Chen 《Hyperfine Interactions》2010,197(1-3):135-141
Annealed (H1) and cold-rolled (H2) HAVAR has been studied using high-pressure synchrotron X-ray diffraction. A structural phase transformation was discovered at ~13 GPa at ambient temperature, transforming from m ??3 m (S.G. 225) to P 63/m m c (S.G. 194) symmetry. The transition was not reversible on pressure release. The low-pressure cubic phase was found to be more compressible than the high-pressure hexagonal phase. Conventional Mössbauer and NFS shows that the HAVAR is not magnetic at room temperature and no splitting is observed. The SQUID indicates a huge difference in the temperature dependence of the magnetic susceptibility between the cold Rolled HAVAR compared to the annealed HAVAR. 相似文献
77.
We consider the deadline problem and budget problem of the nonlinear time–cost tradeoff project scheduling model in a series–parallel activity network. We develop fully polynomial-time approximation schemes for both problems using K-approximation sets and functions, together with series and parallel reductions. 相似文献
78.
We have conducted ab initio molecular dynamics simulations of hydrogen fluoride (HF) at pressures of 5-66 GPa along the 900 K isotherm. We predict a superionic phase at 33 GPa, where the fluorine atoms are fixed in a bcc lattice while the hydrogen atoms diffuse rapidly with a diffusion constant between 2 x 10(-5) and 5 x 10(-5)cm(2)s. We find that a transformation from asymmetric to symmetric hydrogen bonding occurs in HF at 66 GPa and 900 K. With superionic HF we have discovered a model system where symmetric hydrogen bonding occurs at experimentally achievable conditions. Given previous results on superionic H(2)O [Goldman et al., Phys. Rev. Lett. 94, 217801 (2005)] and NH(3) [Cavazzoni et al., Science 283, 44 (1999)], we conclude that high P, T superionic phases of electronegative element hydrides could be common. 相似文献
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80.
New physics contributions to Bs-Bs mixing can be parametrized by the size (rs2) and the phase (2thetas) of the total mixing amplitude relative to the standard model amplitude. The phase has so far been unconstrained. We first use the D0 measurement of the semileptonic CP asymmetry ASL to obtain the first constraint on the semileptonic CP asymmetry in Bs decays, ASLs=-0.008+/-0.011. Then we combine recent measurements by the CDF and D0 Collaborations--the mass difference (DeltaMs), the width difference (DeltaGammas), and ASL;s--to constrain 2thetas. The errors on DeltaGammas and ASL;s should still be reduced to have a sensitive probe of the phase, yet the central values are such that the regions around 2thetas approximately 3pi/2 and, in particular, 2thetas approximately pi/2, are disfavored. 相似文献