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101.
In this paper, the best constant with respect to an inequality for martingales in Hall and Heyde (1980) is obtained. As a consequence, some large deviations with martingale difference and moving average process are established. 相似文献
102.
Dezhi Liu Guiyuan YangWei Zhang 《Journal of Computational and Applied Mathematics》2011,235(10):3115-3120
In the paper, the asymptotic mean square stability of the zero solution for neutral stochastic delay differential equations with Poisson jumps is studied by fixed points theory without Lyapunov functions. The coefficient functions have not been asked for a fixed sign, and the sufficient condition for mean square stability has been obtained. Therefore, some well-known results are improved and generalized. 相似文献
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Zhu Yanling 《Annals of Differential Equations》2007,23(1):119-126
By using the theory of coincidence degree, we study a kind of periodic solution to p-Laplacian differential equation with a deviating argument such as ((?)p(x'(t)))' f(x(t)) g(x(t - r(t))) = e(t), a result on the existence of periodic solution is obtained. 相似文献
106.
Summary A sensitive and selective spectrophotometric method has been developed for the determination of nickel, based on the formation of red ternary complex of nickel with cadion and 1,10-phenanthro- line in alkaline solution (0.5N NaOH). The complex is quantitatively extracted by chloroform and exhibits an absorption maximum at 505 nm. Beer's law is obeyed in the concentration range of 0–2.5g of Ni(II)/5 ml chloroform. The Sandell sensitivity and molar absorptivity of the reaction are 0.000587g cm–2 and 1.0×l05l· mol–1·cm–1, respectively. The method has been applied to the determination of nickel in alloy steels, aluminium alloys and soils.
Extraktion und spektrophotometrische Bestimmung von Nickel mit Cadion und 1,10-Pbenanthrolin als ternärer Komplex
Zusammenfassung Eine empfindliche und selektive Methode zur Bestimmung von Nickel mit Cadion und 1,10-Phenanthrolin wurde ausgearbeitet. Sie beruht auf der Bildung eines roten ternären Komplexes in alkalischer Lösung (0.5N NaOH). Bei 505 nm entspricht die Färbung dem Beerschen Gesetz zwischen 0 und 2,5g Ni(II)/5 ml Chloroform. Der Komplex läßt sich mit Chloroform extrahieren. Die Empfindlichkeit der Reaktion beträgt 0,000587g· cm–2 und die molare Absorption 1.0×105l·mol–1·cm–1. Die Bestimmung von Nickel in Stahl, Aluminiumlegierungen und Böden ergab zufriedenstellende Resultate.相似文献
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Aurone derivatives were synthesized in good to high yields by PBu3‐catalyzed intramolecular 5‐exo cyclization of 2‐alkynoylphenols. The reaction proceeds in high regioselectivity without forming 6‐endo cyclization products. 相似文献
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AbstractA series of tertiary amine containing PHMEMA-PEG-PHMEMA ABA triblock copolymers were synthesized by atom transfer radical polymerization (ATRP) using bromine-capped poly(ethylene glycol) (Br-PEG-Br) and 2-(hexamethyleneimino)ethyl methacrylate (HMEMA) as macro-initiator and monomers, respectively. The chemical structures and molecular weights of triblock copolymers were characterized by 1H NMR and gel permeation chromatography (GPC). The self-assembly behaviors of copolymers in different pH conditions were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Triblock copolymers self-assembled into micelles in water (pH 7.4) and the micelles disassembled at acidic pH (pH 5.0). Anticancer drug doxorubicin (DOX) was used as a drug model and physically encapsulated into polymeric micelles. The drug release of DOX-loaded polymeric micelles was pH-responsive; the drug-loaded micelles that had higher contents of tertiary amine in polymer pendant groups showed faster release speed. In addition, the drug-loaded micelles showed excellent inhibition efficacy against HeLa cells in vitro. 相似文献