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New Metal Chelates as Antioxidant Stabilizers for Polymers and Low Molecular-Weight Substances
Published in Richard A. Pethrick, Gennadi E. Zaikov, Teiji Tsuruta, Naoyuki Koide, Polymer Yearbook 13, 2019
V.G. Vinogradova, A.B. Mazaletskii
In addition to the above mentioned copper complexes XVIII and XIX, the second group of complexes is composed of all bicyclic and tricyclic copper chelates with active centers Cu(N,N)2 and Cu(N4), sulphur- and nitrogen-containing bicyclic copper chelate XX and bicyclic cobalt chelate XXIII with active center Co(N,NH)2. All these complexes, as well as Zn and Bi dithiocarbamates XXIV and XXV, are able to terminate the oxidation chains in reactions with “ether-type” peroxy radicals. Upon oxidation of oligomeric PEGs and PEG-1500 these chelates are likely to interact with peroxy radicals of both types. At any rate, copper chelates I and XX inhibit efficiently the initiated cyclohexanol oxidation, which is mediated by α-hydroxyperoxy radicals.
Anionically Prepared Telechelic Polymers
Published in Eric J. Goethals, Telechelic Polymers: Synthesis and Applications, 2018
David H. Richards, Geoffrey C. Eastmond, Malcolm J. Stewart
This difficult procedure has been developed by Nitadori et al.89 as a means of ultimately making block copolymers. It is a system in which it is not easy to avoid side reactions, but the following procedure allows them to be minimized. Living polymer, as the potassium salt, is reacted with two to four times excess toluene diisocyanate (TDI). The terminal group thus created (Structure XVIII, Equation 31) is capable of polymerizing isocyanate groups, but this is () ()
Nineteen Phases of Ice and Counting
Published in Fausto Martelli, Properties of Water from Numerical and Experimental Perspectives, 2022
Alfred Amon, Bharvi Chikani, Siriney O. Halukeerthi, Carissa Ponan, Alexander Rosu-Finsen, Zainab Sharif, Rachael L. Smith, Sukhpreet K. Talewar, Christoph G. Salzmann
Subjecting ice VII to sophisticated laser-driven shock-compression, superionic ice XVIII with Fm-3m space group symmetry forms above 100 GPa and 2000 K (Millot et al. 2018, Millot et al. 2019). The hydrogen atoms in ice XVIII are free to move between the densely packed oxygen atoms. Ice XVIII has a melting point near 5000 K at 190 GPa which means that it may be present in the interiors of Neptune and Uranus. A variety of other superionic ices have been predicted computationally (Sun et al. 2015).
Detection techniques for mitigating the nonlinear distortion of ADPCM link
Published in Australian Journal of Multi-Disciplinary Engineering, 2018
The 32 kb/s ADPCM link is used in various digital communication networks, including corporate private networks, and long-distance transmission lines in public-switched network. Furthermore, ADPCM can be easily and efficiently incorporated together with digital speech interpolation in Digital Circuit Multiplication Equipment (DCME), which had been scheduled to be installed in optical submarine cable systems and international satellite communication systems. In any application, voiceband data signals as well as speech signals must be transmitted, and adequate transmission performance should be maintained not only for speech signals but also for high-speed voiceband data signals. The standard 32 kb/s ADPCM algorithm provides a good performance for speech signals, and can transmit voiceband data signals up to 4.8 kb/s since it was recognised at study group XVIII meeting (CCITT Recommendation G.721, 1984) that the 32 kb/s ADPCM adds severe nonlinear distortion to the voiceband data signal at high data rate. However, speech and voiceband data signals have different characteristics in time domain and frequency domain. The differences between them increase the difficulty of adequate transmission performance for both.
Deep Learning for Multigroup Cross-Section Representation in Two-Step Core Calculations
Published in Nuclear Science and Engineering, 2023
Nicolas Martin, Zachary Prince, Vincent Labouré, Mauricio Tano-Retamales
Similar to what was presented in Sec. III.C for the HTGR case, the validation data set was employed to estimate the generalization error for the piecewise multilinear model built on the training data set, which was then used as a goal for the hyperparameter search. Since the total number of multigroup cross sections was significantly larger with a 24-group structure, only the total cross sections are provided in Table XVIII.