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41.
Silicon - The products of solid-phase mechanochemical interaction between pyrocatechol and silicon dioxide yielding a powdered composite were studied using a number of physicochemical methods. This... 相似文献
42.
Lun Feng William G. Fahrenholtz Gregory E. Hilmas Frédéric Monteverde 《Journal of the European Ceramic Society》2021,41(1):92-100
Dense high-entropy (Hf,Zr,Ti,Ta,Nb)B2 ceramics with Nb contents ranging from 0 to 20 at% were produced by a two-step spark plasma sintering process. X-ray diffraction indicated that a single-phase with hexagonal structure was detected in the composition without Nb. In contrast, two phases with the same hexagonal structure, but slightly different lattice parameters were present in compositions containing Nb. The addition of Nb resulted in the presence of a Nb-rich second phase and the amount of the second phase increased as the Nb content increased. The relative densities were all >99.5 %, but decreased from ~100 % to ~99.5 % as the Nb content increased from 0 to 20 at%. The average grain size decreased from 13.9 ± 5.5 μm for the composition without Nb additions to 5.2 ± 2.0 μm for the composition containing 20 at% Nb. The reduction of grain size with increasing Nb content was due to the suppression of grain growth by the Nb-rich second phase. The addition of Nb increased Young’s modulus and Vickers hardness, but decreased shear modulus. While some Nb dissolved into the main phase, a Nb-rich second phase was formed in all Nb-containing compositions. 相似文献
43.
Golubev N. V. Ignat’eva E. S. Maurus A. A. Ziyatdinova M. Z. Lopatina E. V. Lorenzi R. Paleari A. Sigaev V. N. 《Glass and Ceramics》2021,77(11-12):415-418
Glass and Ceramics - The influence of Al2O3 as an additive and the heat-treatment regime on the luminescence spectra of gallate glass-ceramics was investigated. It is shown that its luminescence... 相似文献
44.
Wireless Networks - Orthogonal frequency-division multiplexing with random multiple access (OFDRMA) is discussed for down-link communications, whereby a single base-station transmits information... 相似文献
45.
46.
Mahantesh H. M. Nageswara Guptha M. Hema M. S. 《Wireless Personal Communications》2021,120(3):2349-2365
Wireless Personal Communications - 2In Software Defined Network based Internet of Things (SDN-IoT), the path selected for forwarding the packets as per rules, should be Quality of Service (QoS)... 相似文献
47.
Kruglikov S. S. Zagorskii D. L. Kolesnikov V. A. Doludenko I. M. Bedin S. A. 《Theoretical Foundations of Chemical Engineering》2021,55(5):942-951
Theoretical Foundations of Chemical Engineering - The effect of the electrolyte composition, mass-transfer conditions, pore diameter, interpore distance, and electric parameters on the formation of... 相似文献
48.
Vasanthapriya R. Neelakandeswari N. Uthayarani K. Chitra M. 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(11):4272-4280
Journal of Inorganic and Organometallic Polymers and Materials - This paper reports the performance of alizarin based SnO2 dye-sensitized solar cells. A novel template assisted method has been... 相似文献
49.
Abbas Khan. Dong-Qing Wei Kafila Kousar Jehad Abubaker Sajjad Ahmad Javaid Ali Fahd Al-Mulla Syed Shujait Ali N. Nizam-Uddin Abrar Mohammad Sayaf Anwar Mohammad 《Chembiochem : a European journal of chemical biology》2021,22(16):2641-2649
The evolution of new SARS-CoV-2 variants around the globe has made the COVID-19 pandemic more worrisome, further pressuring the health care system and immunity. Novel variations that are unique to the receptor-binding motif (RBM) of the receptor-binding domain (RBD) spike glycoprotein, i. e. L452R-E484Q, may play a different role in the B.1.617 (also known as G/452R.V3) variant's pathogenicity and better survival compared to the wild type. Therefore, a thorough analysis is needed to understand the impact of these mutations on binding with host receptor (RBD) and to guide new therapeutics development. In this study, we used structural and biomolecular simulation techniques to explore the impact of specific mutations (L452R-E484Q) in the B.1.617 variant on the binding of RBD to the host receptor ACE2. Our analysis revealed that the B.1.617 variant possesses different dynamic behaviours by altering dynamic-stability, residual flexibility and structural compactness. Moreover, the new variant had altered the bonding network and structural-dynamics properties significantly. MM/GBSA technique was used, which further established the binding differences between the wild type and B.1.617 variant. In conclusion, this study provides a strong impetus to develop novel drugs against the new SARS-CoV-2 variants. 相似文献
50.
Bolshova T. A. Chernov A. A. Shmakov A. G. 《Combustion, Explosion, and Shock Waves》2021,57(2):159-170
Combustion, Explosion, and Shock Waves - Methyl methacrylate (MMA) is the main pyrolysis product of the widely used polymer polymethyl methacrylate; therefore, a compact mechanism of MMA... 相似文献