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Applied Biochemistry and Biotechnology - 相似文献
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Calculation of the oblique shock wave of real gases is a difficult and time consuming problem because it involves numerical solution of a set of 10 equations, two of which (i.e., the equation of state and enthalpy function)—if available—are of a very complicated algebraic form. The present work presents a generalized method for calculating oblique shock waves of real gases, based on the Redlich-Kwong equation of state. Also described is an exact method applicable when the exact equation of state and enthalpy function of a real gas are available. Application of the generalized and the exact methods in the case of real air showed that the former is very accurate and at least twenty times faster than the latter. An additional contribution of the study is the derivation of real gas oblique shock wave equations, which are of the same algebraic form as the well known ideal gas normal shock wave relations. 相似文献
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M. Katsikini E. C. Paloura J. Antonopoulos P. Bressler T. D. Moustakas 《Journal of Crystal Growth》2001,230(3-4):405-409
It is demonstrated that the NEXAFS spectra are a “fingerprint” of the symmetry and the composition of the binary nitrides GaN, AlN and InN, as well as of their ternary alloys In0.16Ga0.84N and AlyGa1−yN. From the angular dependence of the N-K-edge NEXAFS spectra, the hexagonal symmetry of the under study compounds is deduced and the (px, py) or pz character of the final state is identified. The energy position of the absorption edge (Eabs) of the binary compounds GaN, AlN and InN is found to red-shift linearly with the atomic number of the cation. The Eabs of the AlyGa1−yN alloys takes values in between those corresponding to the parent compounds AlN and GaN. Contrary to that, the Eabs of In0.16Ga0.84N is red-shifted relative to that of GaN and InN, probably due to ordering and/or phase separation phenomena. The EXAFS analysis results reveal that the first nearest-neighbour shell around the N atom, which consists of Ga atoms, is distorted in both GaN and AlxGa1−xN for x<0.5. 相似文献
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C.G. Antonopoulos A.S. Fokas T.C. Bountis 《The European physical journal. Special topics》2016,225(6-7):1255-1269
We model the neuronal circuit of the C.elegans soil worm in terms of a Hindmarsh-Rose system of ordinary differential equations, dividing its circuit into six communities which are determined via the Walktrap and Louvain methods. Using the numerical solution of these equations, we analyze important measures of dynamical complexity, namely synchronicity, the largest Lyapunov exponent, and the ΦAR auto-regressive integrated information theory measure. We show that ΦAR provides a useful measure of the information contained in the C.elegans brain dynamic network. Our analysis reveals that the C.elegans brain dynamic network generates more information than the sum of its constituent parts, and that attains higher levels of integrated information for couplings for which either all its communities are highly synchronized, or there is a mixed state of highly synchronized and desynchronized communities. 相似文献
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A rigorous crystallographic framework for the characterisation ofinterfacial defects which separate (i) crystallographicallyequivalent and (ii) distinct interfacial structures is described. Forthis purpose, the Volterra approach for characterising line defectsis adapted for bicrystalline media. Defects in the distinct categoryare described in interfaces of materials with the L12(A3B) structure. The diffusive flux of materialassociated with the motion of such defects is determined and comparedwith fluxes for defects separating equivalent structures. This isdone by modifying a recently developed equation which defines thediffusive flux in terms of the defect's topological parameters. It isshown that grain boundary dislocations in the distinct category within-plane Burgers vectors may not be glissile but may requirediffusive flux for their motion. 相似文献
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Applied Biochemistry and Biotechnology - 相似文献
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A numerical method is proposed for detecting resonances of conservative maps which reduces this task to an optimization problem. We then solve this problem using evolutionary algorithms, which are methods for global optimization inspired by biological evolution. The proposed methodology is simple and can be easily applied to maps of arbitrary dimensions. In this Letter we apply it to several examples of 2- and 4-dimensional conservative maps, with quite promising results concerning integrability, the location of resonances and the presence of chaotic regions surrounding the island chains that correspond to these resonances. 相似文献
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Enzymatically digested oligo-iota-carrageenans were separated with liquid chromatography, coupled to evaporative light scattering detection. As expected, compared to oligo-kappa-carrageenans, the additional sulphate group in the neocarrabiose unit of iota-carrageenans significantly modified the separation mechanisms on ion-exchange chromatography, porous graphitic carbon and ion-pair chromatography. The oligomers were then isolated and characterised off-line with electrospray ionisation mass spectrometry in positive-ion mode. The tetrasaccharide, hexasaccharide and octasaccharide that were identified were associated with protonated heptylamine molecules whose number depended on the number of sulphate groups. 相似文献
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Antonopoulos A Bonnet P Botek E Debrun JL Hakim B Herbreteau B Morin-Allory L 《Rapid communications in mass spectrometry : RCM》2003,17(2):122-125
The mechanism of attachment of Na(+) on glucose, methyl-alpha-D-glucose, methyl-beta-D-glucose, 3-O-methylglucose, tetra-O-methylglucose, and also on galactose and methyl-beta-D-galactose, was studied. For this we measured the ion yields for the complex [sugar-Na(+)] formed by ionisation by matrix-assisted laser desorption/ionisation (MALDI) and ionspray. These data were compared with the relative volatilities and hydrophobicities of the sugars, measured by evaporative light scattering and reversed-phase liquid chromatography, respectively. Some formation enthalpies for the complexes [sugar-Na(+)], starting from the sugar and the cation, were obtained by ab initio calculations. No simple correlations could be observed between the ion yields and the parameters studied, so that the cationisation mechanism of the sugars remains unclear. 相似文献