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991.
NLS approximation of time oscillatory long waves for equations with quasilinear quadratic terms 下载免费PDF全文
Martina Chirilus‐Bruckner Wolf‐Patrick Düll Guido Schneider 《Mathematische Nachrichten》2015,288(2-3):158-166
We consider a nonlinear wave equation with a quasilinear quadratic nonlinearity. Slow spatial and temporal modulations of the envelope of an underlying carrier wave can be described formally by an NLS equation. It is the purpose of this paper to present a method which allows to prove error estimates between this formal approximation and true solutions of the quasilinear wave equation in case . The paper contains the first validity proof of the NLS approximation for a nonlinear wave equation with quasilinear quadratic terms. 相似文献
992.
Eun Hee Min S. R. Simon Ting Laurent Billon Martina H. Stenzel 《Journal of polymer science. Part A, Polymer chemistry》2010,48(15):3440-3455
Stable and surface‐modified films with regular porous arrays were created by crosslinking honeycomb structured porous films prepared via breath figures from poly(styrene‐co‐maleic anhydride). The formation of open or closed pores of the films was controlled by the addition of a polyion complex. Subsequent crosslinking of the films with 1,8‐diaminooctane led to films, which maintain their structure in solvents. In addition, excess amino functionality after crosslinking allowed the attachment of RAFT agent, 3‐benzylsulfanyl thiocarbonyl sulfanylpropionic acid, for the controlled surface polymerization of N‐isopropyl acrylamide (NIPAAm) and N‐acryloyl glucosamine (AGA). The attachment of thermo‐responsive glycopolymers onto the honeycomb structured porous films was confirmed using contact angle measurements and confocal fluorescence microscopy. Cleavage of surface anchored polymers via aminolysis revealed that the molecular weights of the surface grafted chains are significantly larger than the molecular weight of the chains generated in solution. The honeycomb structured porous films with their grafted PNIPAAm‐ran‐PAGA polymer chains showed selective recognition of Concanavalin A (ConA). Below the lower critical solution temperature (LCST) of the surface, the conjugation is switched off, while above the LCST the surface grafted glucose moieties bind strongly to ConA. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3440–3455, 2010 相似文献
993.
Antoine Bousquet Christopher Barner‐Kowollik Martina H. Stenzel 《Journal of polymer science. Part A, Polymer chemistry》2010,48(8):1773-1781
Comb polymers were synthesized by the “grafting‐onto” method via a combination of Reversible Addition‐Fragmentation Chain Transfer (RAFT) polymerization and the hetero‐Diels‐Alder (HDA) cycloaddition. The HDA reactive monomer trans, trans‐hexa‐2,4‐dienylacrylate (ttHA) was copolymerized with styrene via the RAFT process. Crosslinking was minimized by decreasing the monomer concentration—whilst keeping monomer to polymer conversions low—resulting in reactive backbones with on average one reactive pendant diene groups for 10 styrene units. The HDA cycloaddition was performed between the diene functions of the copolymer and a poly(n‐butyl acrylate) (PnBA) prepared via RAFT polymerization with pyridin‐2‐yldithioformate, which can act as a dienophile. The coupling reactions were performed within 24 h at 50 °C and the grafting yield varies from 75% to 100%, depending on the number average molecular weight of the PnBA (3500 g mol?1 < Mn < 13,000 g mol?1) grafted chain and the reaction stoichiometry. The molecular weights of the grafted block copolymers range from 19,000 g mol?1 to 58,000 g mol?1 with polydispersities close to 1.25. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1773–1781, 2010 相似文献
994.
Dr. Markus Follmann Dr. Nils Griebenow Dr. Michael G. Hahn Dr. Ingo Hartung Dr. Franz‐Josef Mais Dr. Joachim Mittendorf Dr. Martina Schäfer Dr. Hartmut Schirok Dr. Johannes‐Peter Stasch Dr. Friederike Stoll Dr. Alexander Straub Prof. Dr. Peter Jeschke Dr. Ralf Nauen Dr. Michael Edmund Beck Dr. Hans‐Wilhelm Engels Dr. Hans‐Georg Pirkl Dr. Reinhard Albers Dr. Rolf W. Albach Dr. Jens Krause Dr. Andreas Hoffmann Dr. Holger Casselmann Dr. Jeff Dormish 《Angewandte Chemie (International ed. in English)》2013,52(36):9333-9333
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Alessandra Lorenzetti Stefano Besco Denis Hrelja Martina Roso Emanuela Gallo Bernhard Schartel Michele Modesti 《Polymer Degradation and Stability》2013
Nanocomposites of a charring polymer (like polyurethane foam) filled with aluminum phosphinate (AlPi) with or without melamine cyanurate (MelCy) have been prepared by microwave processing and their thermal stability and fire behavior have been studied. Results on the interaction between flame retardants and layered silicates were provided as well as detailed investigation of the char strength, which has been carried out using a suitably developed method based on dynamic-mechanic analysis. 相似文献
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Guido L. B. Wiesenberg Martina Gocke Yakov Kuzyakov 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(1):99-108
Two powerful approaches are frequently used to trace incorporation and degradation of plant derived C in soil: 14C labelling/chasing and analysis of lipid composition. In this study, we coupled these approaches in order to trace short
term incorporation of plant derived lipids into rhizosphere and non-rhizosphere soil. Methodological optimization was required
and implied 14C liquid scintillation counting improvement for plant lipid extracts taking into account organic solvents, solvent-to-scintillation
cocktail ratio, and amount of lipids. Following method optimization, 14C data of fatty acids indicated a notable contribution of root derived lipids to rhizosphere and non-rhizosphere soil. Coupling
of 14C labelling/chasing with lipid analysis is a powerful and cheap approach for tracing of root derived C in soil allowing for
estimation of C budget, for determination of C formation and translocation within plants and from plant to soil, as well as
for identification of short term dynamics of specific compound classes within soil. 相似文献
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