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81.
Konyukhov V. K. Stepanov E. V. Borisov S. K. 《Bulletin of the Lebedev Physics Institute》2020,47(2):59-63
Bulletin of the Lebedev Physics Institute - Abstract—The self-similarity effect during rarefied water vapor flow between two finite-volume vessels is repeatedly recorded with a similarity... 相似文献
82.
The characteristics of heat transfer in the three-dimensional stagnationpoint flow past a stretching/shrinking surface of the Al_2O_3-Cu/H_2O hybrid nanofluid with anisotropic slip are investigated. The partial differential equations are converted into a system of ordinary differential equations by valid similarity transformations. The simplified mathematical model is solved computationally by the bvp4c approach in the MATLAB operating system. This solving method is capable of generating more than one solutions when suitable initial guesses are proposed. The results are proven to have dual solutions, which consequently lead to the application of a stability analysis that verifies the achievability of the first solution. The findings reveal infinite values of the dual solutions at several measured parameters causing the non-appearance of the turning points and the critical values. The skin friction increases with the addition of nanoparticles, while the escalation of the anisotropic slip effect causes a reduction in the heat transfer rate. 相似文献
83.
Zhihua Xie Dimitrios Pavlidis Pablo Salinas Christopher C. Pain Omar K. Matar 《国际流体数值方法杂志》2020,92(7):765-784
A novel control volume finite element method with adaptive anisotropic unstructured meshes is presented for three-dimensional three-phase flows with interfacial tension. The numerical framework consists of a mixed control volume and finite element formulation with a new P1DG-P2 elements (linear discontinuous velocity between elements and quadratic continuous pressure between elements). A “volume of fluid” type method is used for the interface capturing, which is based on compressive control volume advection and second-order finite element methods. A force-balanced continuum surface force model is employed for the interfacial tension on unstructured meshes. The interfacial tension coefficient decomposition method is also used to deal with interfacial tension pairings between different phases. Numerical examples of benchmark tests and the dynamics of three-dimensional three-phase rising bubble, and droplet impact are presented. The results are compared with the analytical solutions and previously published experimental data, demonstrating the capability of the present method. 相似文献
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86.
Temperature Evolution of the Dielectric Response of α-Lactose Monohydrate in the THz Frequency Range
Komandin G. A. Porodinkov O. E. Nozdrin V. S. Musina G. R. Chernomyrdin N. V. Zaytsev K. I. Spektor I. E. 《Optics and Spectroscopy》2020,128(6):752-758
Optics and Spectroscopy - Transmission spectra of pressed microcrystalline α-lactose monohydrate samples have been measured by THz time-domain spectroscopy in the temperature range of... 相似文献
87.
Mechanics of Composite Materials - Based on the classical laminate theory and proceeding from the necessary and sufficient conditions for the hygrothermal stability of materials, interlayer hybrid... 相似文献
88.
Elyashevich G. K. Kuryndin I. S. Rozova E. Yu. Saprykina N. N. 《Physics of the Solid State》2020,62(3):566-573
Physics of the Solid State - The preparation method to obtain the new hybrid piezoelectric systems is developed. In it, layer-by-layer oxidative polymerization of aniline is performed in situ on... 相似文献
89.
Jrme Canivet Elise Bernoud Jonathan Bonnefoy Alexandre Legrand Tanya K. Todorova Elsje Alessandra Quadrelli Caroline Mellot-Draznieks 《Chemical science》2020,11(33):8800
Understanding and controlling molecular recognition mechanisms at a chiral solid interface is a continuously addressed challenge in heterogeneous catalysis. Here, the molecular recognition of a chiral peptide-functionalized metal–organic framework (MOF) catalyst towards a pro-chiral substrate is evaluated experimentally and in silico. The MIL-101 metal–organic framework is used as a macroligand for hosting a Noyori-type chiral ruthenium molecular catalyst, namely (benzene)Ru@MIL-101-NH-Gly-Pro. Its catalytic perfomance toward the asymmetric transfer hydrogenation (ATH) of acetophenone into R- and S-phenylethanol are assessed. The excellent match between the experimentally obtained enantiomeric excesses and the computational outcomes provides a robust atomic-level rationale for the observed product selectivities. The unprecedented role of the MOF in confining the molecular Ru-catalyst and in determining the access of the prochiral substrate to the active site is revealed in terms of highly face-specific host–guest interactions. The predicted surface-specific face differentiation of the prochiral substrate is experimentally corroborated since a three-fold increase in enantiomeric excess is obtained with the heterogeneous MOF-based catalyst when compared to its homogeneous molecular counterpart.Understanding and controlling molecular recognition mechanisms at a chiral solid interface has been addressed in metal–organic framework catalysts for the asymmetric transfer hydrogenation reaction. 相似文献
90.