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181.
Jaume Llibre Paulo R. da Silva Marco A. Teixeira 《Journal of Dynamics and Differential Equations》2012,24(1):1-12
In this article we establish an interaction between non-smooth systems, geometric singular perturbation theory and synchronization
phenomena. We find conditions for a non-smooth vector fields be locally synchronized. Moreover its regularization provide
a singular perturbation problem with attracting critical manifold. We also state a result about the synchronization which
occurs in the regularization of the fold-fold case. We restrict ourselves to the 3-dimensional systems (ℓ = 3) and consider the case known as a T-singularity. 相似文献
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Dr. Sumith A. Kularatne Vishal Deshmukh Dr. Marco Gymnopoulos Dr. Sandra L. Biroc Dr. Jinming Xia Shailaja Srinagesh Dr. Ying Sun Dr. Ning Zou Dr. Mark Shimazu Dr. Jason Pinkstaff Dr. Semsi Ensari Nick Knudsen Anthony Manibusan Dr. Jun Y. Axup Dr. Chan Hyuk Kim Prof. Vaughn V. Smider Dr. Tsotne Javahishvili Prof.Dr. Peter G. Schultz 《Angewandte Chemie (International ed. in English)》2013,52(46):12101-12104
184.
Tommaso Bruno Marco M. Peloso Anita Tabacco Maria Vallarino 《Journal of Functional Analysis》2019,276(10):3014-3050
Let G be a noncompact connected Lie group, denote with ρ a right Haar measure and choose a family of linearly independent left-invariant vector fields X on G satisfying Hörmander's condition. Let χ be a positive character of G and consider the measure whose density with respect to ρ is χ. In this paper, we introduce Sobolev spaces adapted to X and (, ) and study embedding theorems and algebra properties of these spaces. As an application, we prove local well-posedness and regularity results of solutions of some nonlinear heat and Schrödinger equations on the group. 相似文献
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187.
Polymer-Mercury Coated Screen-Printed Sensors for Electrochemical Stripping Analysis of Heavy Metals
Ilaria Palchetti Sanaa Majid Alessandra Kicela Giovanna Marrazza Marco Mascini 《International journal of environmental analytical chemistry》2013,93(7-8):701-711
In the perspective of in-field stripping analysis of heavy metals, the use and disposal of toxic mercury solutions (necessary to plate a mercury film on a carbon electrode surface) presents a problem. The aim of this work was the development of mercury coated screen-printed electrodes previously prepared in the lab and ready to use in-field. Thus some commercially available polymers like Nafion®, Eastman Kodak AQ29®, and Methocel® were investigated as mercury entrapping systems for electrochemical stripping analysis of heavy metals. Screen-printed disposable cells with a silver pseudo-reference electrode, a graphite counter electrode, and a graphite working electrode were used. To modify the sensor, the polymer solution was cast onto the carbon working electrode surface. Detection limits of 0.8 and 1 μg/L were obtained for lead and cadmium respectively. Since Methocel® based electrodes showed the best performance, they were used for the analysis of real samples. The results were compared with those obtained using a classical thin mercury film electrode and ICP spectroscopy. All the experiments reported here were performed in un-deareated solutions as required for in-field analysis. 相似文献
188.
Marco Faustini David Grosso Cédric Boissière Renal Backov Clément Sanchez 《Journal of Sol-Gel Science and Technology》2014,70(2):216-226
Integrative sol–gel chemistry based strategies allow, through the strong coupling between materials chemistry and advanced processing, the fabrication of functional inorganic and hybrid materials. The following article will highlight some of the main accomplishments performed during the last years in the design of nano- and multi-scale structured materials shaped as thin films, powders and monoliths with additional functionalities and outstanding properties in several fields of application such as optics, catalysis and nanomedicine. In particular we discuss the key role played by the adapted liquid processing of sol–gel based solution. We will describe some technologies (including dip coating, spray drying, droplet-microfluidics, ink-jet and foaming) in which a high degree of control in term of liquid shaping/evaporation/manipulation is required in order to achieve specific functionalities. 相似文献
189.
The Oxidation of Thiols by Flavoprotein Oxidases: a Biocatalytic Route to Reactive Thiocarbonyls
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Tom A. Ewing Willem P. Dijkman Prof. Dr. Jacques M. Vervoort Marco W. Fraaije Prof. Dr. Willem J. H. van Berkel 《Angewandte Chemie (International ed. in English)》2014,53(48):13206-13209
Flavoprotein oxidases are a diverse class of biocatalysts, most of which catalyze the oxidation of C? O, C? N, or C? C bonds. Flavoprotein oxidases that are known to catalyze the oxidation of C? S bonds are rare, being limited to enzymes that catalyze the oxidative cleavage of thioethers. Herein, we report that various flavoprotein oxidases, previously thought to solely act on alcohols, also catalyze the oxidation of thiols to thiocarbonyls. These results highlight the versatility of enzymatic catalysis and provide a potential biocatalytic route to reactive thiocarbonyl compounds, which have a variety of applications in synthetic organic chemistry. 相似文献
190.
Ricerche di Matematica - This paper provides an account of results and methods from the theory of infinite groups admitting only finitely many normalizers of subgroups with a given property. Some... 相似文献