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81.
Recently Heyde, Kou and Peng [C.C. Heyde, S.G. Kou, X.H. Peng, What is a good external risk measure: Bridging the gaps between robustness, subadditivity, and insurance risk measures, 2007, preprint.] proposed the notion of a natural risk statistic associated with a finite sample that relaxes the subadditivity assumption in the classical coherent risk statistics. In this note we use convex analysis to provide alternate proofs of the representation results regarding natural risk statistics. 相似文献
82.
Georg Gregor 《Monatshefte für Chemie / Chemical Monthly》1894,15(1):437-445
Ohne Zusammenfassung 相似文献
83.
J. Kunze S. Koelling M. Reich M. A. Wimmer 《Analytical and bioanalytical chemistry》2000,366(2):165-166
A technique for the determination of titanium and zirconium in human blood serum, after pressurized digestion utilizing ICP-MS coupled to an ultrasonic nebulizer (USN) and desolvating membrane is described. As no CRM for titanium is available, zirconium has been determined in order to demonstrate the accuracy of the technique, as the limits in blood are well known. Bone cement consists basically of a polymer, namely polymethylmethacrylate (PMMA). For better X-ray contrast some manufacturers use incorporated ZrO2 with a volume fraction of 10 to 15%. Thus, the zirconium present in the PMMA matrix can be used as an indicator for the PMMA particulate debris. 相似文献
84.
Ingo Klimant Falk Ruckruh Gregor Liebsch Achim Stangelmayer Otto S. Wolfbeis 《Mikrochimica acta》1999,131(1-2):35-46
A new type of phenyl substituted ormosils as a matrix for oxygen-sensitive micro-optodes is described. The new ormosils combine
features of classical polymers such as solubility in organic solvents and those of sol–gel glasses such as mechanical stability
and a porous structure. They make possible a simple and fast fabrication of microsensors with reproducible properties. The
influence of the conditions during the polymerisation process (precursor composition and thermal treatment) on the sensing
properties has been studied in detail. Oxygen-sensitive films with ruthenium(II)–tris-(4,7-diphenyl-1,10-phenanthroline) and
platinum(II)–octaethylporphyrin as indicators were characterised with respect to their mechanical and photophysical properties.
Photostability, oxygen sensitivity, response behaviour and signal intensities of the sensing films and the micro-optodes were
examined. Micro-optodes based on the new sensing materials are fast responding, photostable and can be produced with a sufficient
batch to batch reproducibility. Compared to previously described oxygen micro-optodes, where polystyrene was used as immobilisation
matrix, the new sensors can be autoclaved and show favourable properties such as a faster response and a higher sensitivity.
They possess many potential applications in medical and biological research.
Received June 12, 1998. Revision December 10, 1998. 相似文献
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89.
Catalytic ignition of ionic liquids for propellant applications 总被引:1,自引:0,他引:1
Shamshina JL Smiglak M Drab DM Parker TG Dykes HW Di Salvo R Reich AJ Rogers RD 《Chemical communications (Cambridge, England)》2010,46(47):8965-8967
In this proof of concept study, the ionic liquids, 2-hydroxyethylhydrazinium nitrate and 2-hydroxyethylhydrazinium dinitrate, ignited on contact with preheated Shell 405 (iridium supported on alumina) catalyst and energetically decomposed with no additional ignition source, suggesting a possible route to hydrazine replacements. 相似文献
90.