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101.
Abstract The results of an evaluation of polymers as cryogenic adhesives are presented. It was observed that polyether-based polyurethanes provided the most attractive capability as adhesives for use at liquid hydrogen temperatures. 相似文献
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Wei Zhao Yi Zhang Xiao Wang Xiaowen Hu Feng Liu Thomas P. Russell Guofu Zhou 《Journal of polymer science. Part A, Polymer chemistry》2018,56(20):1369-1375
Block copolymer (BCP) films with long-range lateral ordering and orientation are crucial for many applications. Here, we report a simple, versatile strategy based on a solution casting procedure, to produce millimeter thick film of BCPs with highly oriented nanostructures. Transmission electron microscope (TEM), small angle X-ray scattering (SAXS), and Hansen solubility parameters were used to study the morphology and interactions of the system. A variety of BCP-solvent pairs were investigated. Factors including set-up geometry, BCP characteristics, solvent evaporation, surface tension, and interactions, such as solvent-BCP, solvent-substrate, and BCP-substrate were examined. A mechanism is proposed to describe the observed long-range lateral ordering and orientation in films up to 1 mm in thickness. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1369–1375 相似文献
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Glen A. Russell Rajive K. Khanna 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-4):271-274
Abstract The anion Ph2P? (K+, 18-crown-6) reacts with t-BuHgCl in HMPA to form Ph2PCMe3 by a free radical chain mechanism. In Me2SO, Ph2P(O)CMe3 is produced. Reaction of Ph2P? with PhCOCH2HgCl yields the oxidative dimerization product isolable from HMPA but readily converted to Ph2P(O)P(O)Ph2 in Me2SO. 相似文献
106.
Russell Merris 《Linear and Multilinear Algebra》2013,61(3):171-178
Various results bearing on the construction of bases for symmetry classes of tensors are discussed. Applications are given to the production of explicit homogeneous polynomial representations of the full linear group. 相似文献
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108.
Russell Johnson Yuri Latushkin Roland Schnaubelt 《Journal of Dynamics and Differential Equations》2014,26(2):243-266
We prove the reduction principle and study other attractivity properties of the center and center-unstable manifolds in the vicinity of a steady-state solution for quasilinear systems of parabolic partial differential equations with fully nonlinear boundary conditions on bounded or exterior domains. 相似文献
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Kevin Becker Sebastian Pfütze Dr. Eric Kuhnert Prof. Dr. Russell J. Cox Prof. Dr. Marc Stadler Dr. Frank Surup 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1438-1450
The diversity of azaphilones in stromatal extracts of the fungus Hypoxylon fragiforme was investigated and linked to their biosynthetic machineries by using bioinformatics. Nineteen azaphilone-type compounds were isolated and characterized by NMR spectroscopy and mass spectrometry, and their absolute stereoconfigurations were assigned by using Mosher ester analysis and electronic circular dichroism spectroscopy. Four unprecedented bis-azaphilones, named hybridorubrins A–D, were elucidated, in addition to new fragirubrins F and G and various known mitorubrin derivatives. Only the hybridorubrins, which are composed of mitorubrin and fragirubrin moieties, exhibited strong inhibition of Staphylococcus aureus biofilm formation. Analysis of the genome of H. fragiforme revealed the presence of two separate biosynthetic gene clusters (BGCs) hfaza1 and hfaza2 responsible for azaphilone formation. While the hfaza1 BGC likely encodes the assembly of the backbone and addition of fatty acid moieties to yield the (R)-configured series of fragirubrins, the hfaza2 BGC contains the necessary genes to synthesise the widely distributed (S)-mitorubrins. This study is the first example of two distant cross-acting fungal BGCs collaborating to produce two families of azaphilones and bis-azaphilones derived therefrom. 相似文献