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21.
《Physics letters. A》2019,383(17):2028-2032
We find that the simple coupling of network growth to the position of a random walker on the network generates a traveling wave in the probability distribution of nodes visited by the walker. We argue that the entropy of this probability distribution is bounded as the network size tends to infinity. This means that the growth of a space coupled to a random walker situated in it constrains its dynamics to a set of typical random walker trajectories, and walker trajectories inside the growing space are compressible. 相似文献
22.
《Journal of separation science》2018,41(2):560-570
To explore the global mechanism of Ermiaowan on hyperuricemia regulation, the holistic function of Ermiaowan for hyperuricemia in rats was firstly assessed by the urinary metabonomics method which was based on ultra‐high performance liquid chromatography with electrospray ionization quadrupole time‐of‐flight mass spectrometry. The urinary targeted metabonomics approach combined with the serum biochemical analysis and histological assay was conducted to verify the research result. As a result, the significant differences in metabolic profiles were observed from Ermiaowan‐treated group, model group, and healthy control group by using multivariate statistical approaches. Twenty therapeutic related metabolites were identified in response to the therapeutic effects of Ermiaowan, which were mainly associated with purine metabolism, pyrimidine metabolism, tryptophan metabolism, tricarboxylic acid cycle, and tyrosine metabolism. In addition, the urinary targeted metabonomics study showed that Ermiaowan can better restore the disturbed pathways than Phellodendri cortex and Atractylodis rhizome. The biochemical assay and histopathological assay confirmed that Ermiaowan could significantly reduce uric acid and fibrosis areas of kidney. These results provided new insights into the mechanism of Ermiaowan on hyperuricemia. 相似文献
23.
本文给出对数K-Carleson测度的一个新特征,并以此为工具研究QK空间的乘子代数M(QK),给出乘子代数M(QK)的某些特征描述.利用对数K-Carleson测度及QK空间的一个新特征,建立乘子代数M(QK)上的Corona定理和Wolff定理. 相似文献
24.
《Mathematische Nachrichten》2018,291(10):1470-1485
In this paper we study a class of second order coefficient operators differential equation with general (possibly non local) boundary conditions. We obtain new results extending those given in a previous paper 1 . Existence, uniqueness and optimal regularity of the strict solution are proved in UMD spaces, using the well‐known Dore–Venni theorem. 相似文献
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The recently introduced analytical model for the heat current autocorrelation function of a crystal with a monatomic lattice [Evteev et al., Phil. Mag. 94 (2014) p. 731 and 94 (2014) p. 3992] is employed in conjunction with the Green–Kubo formalism to investigate in detail the results of an equilibrium molecular dynamics calculations of the temperature dependence of the lattice thermal conductivity and phonon dynamics in f.c.c. Ni. Only the contribution to the lattice thermal conductivity determined by the phonon–phonon scattering processes is considered, while the contribution due to phonon–electron scattering processes is intentionally ignored. Nonetheless, during comparison of our data with experiment an estimation of the second contribution is made. Furthermore, by comparing the results obtained for f.c.c. Ni model to those for other models of elemental crystals with the f.c.c. lattice, we give an estimation of the scaling relations of the lattice thermal conductivity with other lattice properties such as the coefficient of thermal expansion and the bulk modulus. Moreover, within the framework of linear response theory and the fluctuation-dissipation theorem, we extend our analysis in this paper into the frequency domain to predict the power spectra of equilibrium fluctuations associated with the phonon-mediated heat dissipation in a monatomic lattice. The practical importance of the analytical treatment lies in the fact that it has the potential to be used in the future to efficiently decode the generic information on the lattice thermal conductivity and phonon dynamics from a power spectrum of the acoustic excitations in a monatomic crystal measured by a spectroscopic technique in the frequency range of about 1–20 THz. 相似文献