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991.
D. Ph. Sikovsky 《Thermophysics and Aeromechanics》2011,18(2):235-254
On the basis of the previously developed asymptotic theory of turbulent particle-laden flow with particle deposition in channels
coupled with the transport model for the particle Reynolds stress, an asymptotic solution to the problem on the deposition
of particles in the limit of high Reynolds numbers was obtained. The numerical calculations confirmed the presence, in the
region of the transition from the diffusion-impaction regime of particle sedimentation to the inertia-moderated regime, bifurcation
phenomenon of a solution found previously in earlier studies. Features of particle accumulation in the viscous sublayer are
analyzed. On the basis of the numerical solution, correlations for particle deposition velocity were obtained. Boundary conditions
of the wall-function type for particle concentration whose use allows widening the applicability limits of the equilibrium
Eulerian models in terms of particle inertia are proposed. 相似文献
992.
993.
Ph. Roche 《Communications in Mathematical Physics》1990,127(2):395-424
We show that cell calculus (first introduced by Ocneanu in the context of relative position of factors) is a technique which permits us to connect different integrable models. It generalizes the Vertex-IRF correspondence. 相似文献
994.
Grillon G Balcou P Chambaret J Hulin D Martino J Moustaizis S Notebaert L Pittman M Pussieux T Rousse A Rousseau J Sebban S Sublemontier O Schmidt M 《Physical review letters》2002,89(6):065005
Following the interaction of superintense, short pulse lasers and plasmas, ions can be accelerated to velocities sufficient to drive nuclear fusion reactions, in particular, by the process of Coulomb explosion of clusters [T. Ditmire, Nature (London) 398, 491 (1999)]]. We show here how short bursts of neutrons can be produced using a jet of low-density deuterated methane clusters. Ion velocity distributions were simultaneously measured by a Thomson parabola mass spectrometer, demonstrating deuteron energies up to 120 keV. We show that, in such conditions, nuclear fusion will occur not only in the hot plasma core, but also in the cold outer region by collision processes. 相似文献
995.
Using a unified macroscopic QED formalism, an integral equation for the van der Waals energy of a two-level atomic system near a carbon nanotube is derived. The equation is valid for both strong and weak atom-vacuum field coupling. By solving it numerically, the inapplicability of weak coupling-based van der Waals interaction models in the close vicinity of the nanotube surface is demonstrated. It is also shown that encapsulation of doped atoms into the nanotube is energetically more favorable than their outside adsorption by the nanotube surface. 相似文献
996.
Yu. A. Fridman Ph. N. Klevets D.A. Matunin O.V. Kozhemyako 《Journal of Physics and Chemistry of Solids》2006,67(12):2458-2467
The phase states of a two-dimensional ferromagnet system with anisotropic exchange interaction have been investigated for various relations between the material constants. It is shown that the competition between the exchange and the one-ion anisotropies, and the account of the magnetodipolar and the magnetoelastic interactions lead to the sequence of the phase transitions. The explicit solutions of the dispersion equation have been found in the homogeneous phase states. 相似文献
997.
Ammonia is important in the atmosphere because it neutralizes acidic species. The relative importance of different inorganic ammonium compounds (chloride, nitrate and sulfate) in marine air chemistry was studied by single-particle characterization with the laser microprobe mass analyser. Standard aerosols were generated as a reference for compound identification, based on the fingerprint spectra obtained, and calculation of the relative sensitivity achieved for different ions in a marine aerosol matrix. The relative sensitivity for ammonium was low. Aerosol samples were collected in the Southern Bight of the North Sea under different meteorological conditions and examined for their ammonium compounds. Samples collected during an inversion period with continental influences showed a much higher content in all particles than samples collected under different meteorological conditions, where ammonium was mostly detected in the submicrometer particle-size range. 相似文献
998.
Ph. K. Hopke R. C. Martin M. A. Evins 《Journal of Radioanalytical and Nuclear Chemistry》1987,112(1):215-222
Three hundred ancient Turkish potsherds were analyzed by instrumental neutron activation analysis, and the resulting data analyzed by several techniques of multivariate statistical analysis, some only recently developed. The programs AGCLUS, MASLOC, and SIMCA were sequentially employed to characterize and group the samples by type of pottery and by site of excavation or collection. Comparison of the statistical analyses by each method provided archaeological insight into the site/type relationships of the samples and ultimately evidence relevant to commercial relations between the ancient communities and to specialization of pottery production over time. The techniques used for statistical analysis were found to be of significant potential utility in the future analysis of other archaeometric data sets. 相似文献
999.
1000.
C. Hubert S. Houari F. Lecomte V. Houbart C. De Bleye M. Fillet G. Piel E. Rozet Ph. Hubert 《Journal of chromatography. A》2010,1217(19):3275-3281
A sensitive and accurate LC/MS method was developed for the monitoring of glucosamine (GLcN) dog plasmatic concentration. In this scope, relatively low plasmatic concentrations of GLcN were expected, ranging from 50 to 1000 ng/mL. Liquid chromatography coupled to simple quadrupole mass spectrometry detection (LC/MS) was selected bringing the selectivity and the sensitivity needed for this application. Additionally, a solid phase extraction (SPE) step was performed to reduce matrix and ion suppression effects. Due to the ionisable character of the compound of interest, a mixed-mode strong cation exchange (Plexa PCX) disposable extraction cartridge (DEC) was selected. The separation was carried out on a Zorbax SB-CN column (5 μm, 4.6 mm i.d. × 250 mm), considering hydrophilic interaction liquid chromatography (HILIC). Indeed, the mobile phase was made of methanol and 5 mM ammonium hydrogen carbonate buffer at pH 7.5 (95/5, v/v). The detection was led at m/z ratios of 180.0 and 417.0, for GLcN and IS, respectively. Reliability of the results was demonstrated through the validation of the method using an approach based on the accuracy profile allowing managing the risk associated to the use of these methods in routine analysis: it is thus guaranteed that each future result will fall in the ±30% acceptance limits with a probability of at least 90%. Successful application of the method to a preliminary pharmacokinetic study illustrated the usefulness of the method for pre-clinical studies. 相似文献