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21.
This study is directed towards investigating the role of the surface treatment of clay particles on the rheological and thermomechanical
behaviour of clay-epoxy blends. Nanocomposites were prepared by mixing small amounts (5–10 mass %) of commercial organoclays
or raw clays with an epoxy system commonly used in civil engineering. Rheological characterisations in the liquid state revealed
a pronounced thixotropic character of the organoclay-based systems, which all exhibited a shear-thinning behaviour above a
critical stress threshold (yield stress), depending on both the intensity of interfacial interactions and the degree of filler
dispersion. On the other hand, systems based on raw clay particles behaved like Newtonian fluids, in the same way as the unreinforced
polymer matrix. Complementary dynamic mechanical analyses (DMA) performed on the cured cross-linked nanocomposites also showed
significant changes in the viscoelastic behaviour of the epoxy matrix due to the introduction of organoclays, whereas only
minor variations were observed following the introduction of raw fillers. These results were consistent with nanoscale morphological
characterisations performed by conventional X-ray diffraction (XRD) on the various hybrid systems. In this context, rheology
and DMA appear as attractive alternative methods for assessing the filler dispersion at a macroscopic (and possibly more relevant)
scale. This research is of practical interest for civil engineers, since clay reinforced-epoxies could in the future be used
as coating materials with enhanced barrier performances, in order to protect infrastructures against environmental ageing
or corrosion. 相似文献
22.
For integers m, k≥1, we investigate the maximum size of a directed cut in directed graphs in which there are m edges and each vertex has either indegree at most k or outdegree at most k. © 2009 Wiley Periodicals, Inc. J Graph Theory 相似文献
23.
Myriam E. Rodríguez Cristian A. Strassert Josefina Awruch Lelia E. Dicelio 《Journal of heterocyclic chemistry》2001,38(2):387-389
The synthesis of tetramethyl‐tetraphthalimidomethyl‐phthalocyaninato zinc(II) ( 6 ) and tetramethyl‐tetraaminomethyl‐phthalocyaninato zinc(II) ( 7 ) is described. 相似文献
24.
Jean-François Pilichowski Myriam Morel Farba Tamboura Stefan Chmela Jacques Lacoste 《Polymer Degradation and Stability》2010,95(9):1575-4515
4-13C-isoprene was prepared by the Wittig reaction. All reaction steps were optimised using unlabelled compounds. By reaction with triphenyl phosphine, 13C labelled methyl iodide afforded labelled methyl-triphenyl phosphine iodide in 84% yield. This reacted with meth acrolein with production of 4-13C-isoprene in 64% yield. Labelled polyisoprene was prepared by anionic polymerisation initiated by t-butyl lithium. Based on 13CH3I the overall yield is ca 30%. The polymer was characterized by 1H and 13C NMR spectroscopy. The contribution of each microstructure was [cis 1-4, 72%]; [trans 1-4, 10%]; [3-4, 18%]. 相似文献
25.
Renaud Beaudegnies Alain De Mesmaeker Aurélie Mallinger Myriam Baalouch André Goetz 《Tetrahedron letters》2010,51(20):2741-3222
We report the design and the efficient synthesis of novel spirocyclopropyl cyclohexane-1,3-dione and -1,3,5-trione units to be incorporated into potent HPPD inhibitors. New routes involving original combinations of synthetic equivalents of α-cyclopropyl ketone-α-anion and α-cyclopropyl ester-β-cation are described. 相似文献
26.
Photochromic powders are powders whose color is sensitive to UV irradiation. When such a powder is exposed to the sunlight or any other UV rays, it becomes darker and then looks back progressively to its initial color. An optical method has been set up in order to quantify these colors variations. We can then quantify the variations in the colorimetric space, and the time response of the coming back phenomenon. 相似文献
27.
Myriam Maumy 《Comptes Rendus Mathematique》2002,334(8):705-708
In this paper, we describe the local behaviour of compound Poisson processes based on a Poisson process and a sequence of independent and identically distributed random weights. These results are motived by their natural counterparts in the theory of empirical processes. To cite this article: M. Maumy, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 705–708. 相似文献
28.
Capillary electrophoresis for rapid identification of monoclonal antibodies for routine application in hospital 下载免费PDF全文
Emmanuel Jaccoulet Claire Smadja Patrice Prognon Myriam Taverna 《Electrophoresis》2015,36(17):2050-2056
mAbs are widely used in cancer therapy. Their compounding, performed just before their administration to patients, is executed in a production unit of the hospital. Identification of these drugs, individually prepared in bags for infusion before patient administration, is of paramount importance to detect potential mistakes during compounding stage. A fast and reliable analytical method based on CZE combined to a cationic capillary coating (hexadimethrine bromide) was developed for identification of the most widely used compounded therapeutic for cancer therapy (bevacizumab, cetuximab, rituximab, and trastuzumab). Considering the high structural and physico‐chemical similarities of these mAbs, an extensive optimization of the BGE composition has been performed. The addition of perchlorate ions and polysorbate in the BGE greatly increased the resolution. To validate the method, an internal standard was used and the relative migration times (RTm) were estimated. Very satisfactory RSDs of the RTm for rituximab (0.76%), cetuximab (0.46%), bevacizumab (0.31%), and trastuzumab (0.60%) were obtained. The intraday and interday RSD of the method were less than 0.32 and 1.3%, respectively for RTm. Significant differences between theses RTms have been demonstrated allowing mAbs identification. Finally, accurate mAbs identification has been demonstrated by a blind test. 相似文献
29.