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91.
Popova N. A. Nikonenko E. L. Tabieva E. E. Uazyrkhanova G. K. 《Russian Physics Journal》2020,63(5):791-796
Russian Physics Journal - The paper presents the transmission electron microscopy investigations of the structure and phase composition of ferritic-perlitic ST2 steel surface after electrolytic... 相似文献
92.
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
93.
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
94.
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
95.
Peter T. Smith Younghoon Kim Dr. Bahiru Punja Benke Prof. Kimoon Kim Prof. Christopher J. Chang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(12):4932-4937
We report a supramolecular strategy for promoting the selective reduction of O2 for direct electrosynthesis of H2O2. We utilized cobalt tetraphenylporphyrin (Co-TPP), an oxygen reduction reaction (ORR) catalyst with highly variable product selectivity, as a building block to assemble the permanently porous supramolecular cage Co-PB-1(6) bearing six Co-TPP subunits connected through twenty-four imine bonds. Reduction of these imine linkers to amines yields the more flexible cage Co-rPB-1(6). Both Co-PB-1(6) and Co-rPB-1(6) cages produce 90–100 % H2O2 from electrochemical ORR catalysis in neutral pH water, whereas the Co-TPP monomer gives a 50 % mixture of H2O2 and H2O. Bimolecular pathways have been implicated in facilitating H2O formation, therefore, we attribute this high H2O2 selectivity to site isolation of the discrete molecular units in each supramolecule. The ability to control reaction selectivity in supramolecular structures beyond traditional host–guest interactions offers new opportunities for designing such architectures for a broader range of catalytic applications. 相似文献
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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
99.
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
100.
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