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111.
Monica Motta Franco Rampazzo 《NoDEA : Nonlinear Differential Equations and Applications》1996,3(2):191-216
We study a space-time extension of the notion of solution to a nonlinear control system with unbounded controls (in the form of derivatives) and state constraints. A natural motivation is provided by minimum problems, where the presence of unbounded controls together with the lack of any coercivity assumption may give rise to minimizing sequences of trajectories which converge to discontinuous maps. The main problem focused on in this paper can be summarized as follows: is the proposed extension a proper extension? Which means: is one able to approximate an extended trajectory with ordinary ones? When the system is subject to a state constraint the answer is generally negative. On the other hand, we prove that under suitable conditions on the vectogram at the boundary points of the constraint set the extension turns out to be proper. 相似文献
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Erika Ferrari Romano Grandi Sandra Lazzari Gaetano Marverti Maria Cecilia Rossi Monica Saladini 《Polyhedron》2007
The NMR study on the interaction of Pt(II) with Amadori compounds is performed. The Amadori compounds are derived from the reaction of β-d-glucose with l-cystine leading to N,N′-di-(1-deoxy-β-fructos-1-yl)-l-cystine [FruCyscys], and with l-methionine leading to N-(1-deoxy-β-fructos-1-yl)-l-methionine [FruMet]. 相似文献
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Hiroshi Kageyama Takashi Watanabe Yoshihiro Tsujimoto Atsushi Kitada Yuji Sumida Kazuyoshi Kanamori Kazuyoshi Yoshimura Naoaki Hayashi Shigetoshi Muranaka Mikio Takano Monica Ceretti Werner Paulus Clemens Ritter Gilles Andr 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2008,120(31):5824-5829
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A new approach to the determination of afiatoxins B1, B2, G1 and G2 is given; the method involves high-performance liquid chromatography with amperometric detection in the differential-pulse mode at the dropping mercury electrode with 1-s drop time. These aflatoxins can be determined simultaneously with good resolution but with some compromise in sensitivity. The detection limit of underivatized aflatoxin standards is around 5 ng. Average recoveries of aflatoxins from peanut butter by the Beebe method were G2 81%, G1 87%, B2 77% and B1 76%. 相似文献
120.
Irache JM Huici M Konecny M Espuelas S Campanero MA Arbos P 《Molecules (Basel, Switzerland)》2005,10(1):126-145
Bioadhesive nanoparticles have been proposed as carriers for the oral delivery of poorly available drugs and facilitate the use of this route. This work summarises some experiments describing the bioadhesive potential of Gantrez nanoparticles fluorescently labeled with rhodamine B isothiocyanate. The adhesive potential of Gantrez was found to be stronger when folded as nanoparticles than in the solubilised form. Conventional nanoparticles displayed a tropism for the upper areas of the gastrointestinal tract, with a maximum of adhesion 30 min post-administration and a decrease in the adhered fraction along the time depending on the given dose. The cross-linkage of nanoparticles with increasing amounts of 1,3-diaminopropane stabilised the resulting carriers and prolonged their half-life in an aqueous environment; although, the adhesive capacity of nanoparticles, the intensity and the relative duration of the adhesive interactions within the gut as a function of the cross-linking degree. Finally, nanoparticles were coated with either gelatin or albumin. In the first case, the presence of gelatin dramatically decreased the initial capacity of these carriers to interact with the gut mucosa and the intensity of these phenomenons. In the latter, bovine serum albumin coated nanoparticles (BSA-NP) showed an important tropism for the stomach mucosa without further significant distribution to other parts of the gut mucosa. 相似文献