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91.
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
92.
In this paper, we continue to study an initial boundary value problems to a model describing the evolution in time of diffusive phase interfaces in sea ice growth. In a previous paper, the global existence and the large-time behavior of weak solutions in one space was studied under Dirichlet boundary conditions. Here, we show that the global existence of weak solutions and the large-time behavior are also studied under Neumann boundary condition. In this paper, we study in space dimension lower than or equal to 3. 相似文献
93.
时间尺度上二阶动力方程三点边值问题解的存在性 总被引:1,自引:0,他引:1
运用锥中twin不动点定理,讨论了时间尺度上二阶动力方程三点边值问题至少有两个正解存在的条件. 相似文献
94.
Shu-jin Wu Xiao-lin Guo Song-qing Lin 《应用数学学报(英文版)》2006,22(4):627-632
The existence and uniqueness in mean square of solutions to certain random impulsive differentialsystems is discussed in this paper.Cauchy-Schwarz inequality,Lipschtiz condition and techniques in stochasticanalysis are employed in achieve the desired results. 相似文献
95.
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
96.
关于Schottky定理与Hayman常数 总被引:1,自引:0,他引:1
本文对于在单位圆盘中不取值0与1的正则函数,利用了这种函数的对数导数模的准确上界与及Hayman常数有关的上界,得到了这种函数模的显式上界与Hayman常数的关系及这种函数的正规级. 相似文献
97.
本文考虑含扰动项的具有正负系数的中立型泛函微分方程一致稳定和渐近稳定的充分条件,推广了现有文献中的结论. 相似文献
98.
99.
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
100.
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