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61.
Journal of Russian Laser Research - In the constant intensity approximation, we study the effects of self-phase and cross-phase modulations in a cubic medium of an optical fiber at four-wave...  相似文献   
62.
Molecular Diversity - Practical synthesis and biological activities of quinazolinyl–triazinyl semicarbazides (10a–j) and quinazolinyl–triazinyl thiosemicarbazides (11a–j)...  相似文献   
63.
Journal of Russian Laser Research - We discuss the use of high-pressure high-temperature (HPHT) diamonds for the determination of trace amounts of various Raman active substances. The amount of the...  相似文献   
64.
Yang  Tianyong  Wang  Bofu  Wu  Jianzhao  Lu  Zhiming  Zhou  Quan 《应用数学和力学(英文版)》2021,42(8):1183-1190
The horizontal convection in a square enclosure driven by a linear temperature profile along the bottom boundary is investigated numerically by using a finite difference method. The Prandtl number is fixed at 4.38, and the Rayleigh number Ra ranges from107 to 1011. The convective flow is steady at a relatively low Rayleigh number, and no thermal plume is observed, whereas it transits to be unsteady when the Rayleigh number increases beyond the critical value. The scaling law for the Nusselt number Nu changes from Rossby's scaling Nu ~ Ra~(1/5) in a steady regime to Nu ~ Ra~(1/4) in an unsteady regime, which agrees well with the theoretically predicted results. Accordingly,the Reynolds number Re scaling varies from Re ~ Ra~(3/11) to Re ~ Ra~(2/5). The investigation on the mean flows shows that the thermal and kinetic boundary layer thickness and the mean temperature in the bulk zone decrease with the increasing Ra. The intensity of fluctuating velocity increases with the increasing Ra.  相似文献   
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In recent years, clapping synchronization between individuals has been widely studied as one of the typical synchronization phenomena. In this paper, we aim to reveal the synchronization mechanism of clapping interactions by observing two individuals’ clapping rhythms in a series of experiments. We find that the two synchronizing clapping rhythm series exhibit long-range cross-correlations(LRCCs);that is, the interaction of clapping rhythms can be seen as a strong-anticipation process. Previous studies have demonstrated that the interactions in local timescales or global matching in statistical structures of fluctuation in long timescales can be sources of the strong-anticipation process. However, the origin of the strong anticipation process often appears elusive in many complex systems. Here, we find that the clapping synchronization process may result from the local interaction between two clapping individuals and may result from the more global coordination between two clapping individuals. We introduce two stochastic models for mutually interacting clapping individuals that generate the LRCCs and prove theoretically that the generation of clapping synchronization process needs to consider both local interaction and global matching. This study provides a statistical framework for studying the internal synchronization mechanism of other complex systems. Our theoretical model can also be applied to study the dynamics of other complex systems with the LRCCs, including finance, transportation, and climate.  相似文献   
67.
Lu  J. F.  Gao  J. H.  Tang  B.  Sun  M.  Ge  H. G. 《Crystallography Reports》2021,66(7):1295-1299
Crystallography Reports - A novel 3D metal coordination polymer, {[Na4(µ2-H2O)(DMF)2(BCT)2]?DMF}n (I) (DMF = N,N-dimethylformamide, H2BCT =...  相似文献   
68.
Mechanics of Composite Materials - Particleboards based on a mixture of grey alder (Alnus incana (L.) Moench) wood particles (sieve fraction 0.4-2 mm) and 15 or 25% of lignin powder obtained by hot...  相似文献   
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Journal of Applied Spectroscopy - The speciation of extracted chromium from ZSM-5 into an ionic liquid (IL) was studied using X-ray absorption near-edge structure (XANES) spectroscopy. The main...  相似文献   
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