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排序方式: 共有161条查询结果,搜索用时 0 毫秒
151.
In this paper, we employ some analysis technics to study the existence of positive periodic solutions to a system of equations with a parameter and impulse on time scales. 相似文献
152.
Some Contributions to Stochastic Asymptotic Stability and Boundedness via Multiple Lyapunov Functions 总被引:1,自引:0,他引:1
Xuerong Mao 《Journal of Mathematical Analysis and Applications》2001,260(2):4123
Most of the existing results on stochastic stability use a single Lyapunov function, but we shall instead use multiple Lyapunov functions in this paper to establish some sufficient criteria for locating the limit sets of solutions of stochastic differential equations. From them follow many useful results on stochastic asymptotic stability and boundedness, which enable us to construct the Lyapunov functions much more easily in applications. In particular, the well-known classical theorem on stochastic asymptotic stability is a special case of our more general results. These show clearly the power of our new results. 相似文献
153.
通过层层静电自组装法将溶菌酶和聚苯乙烯磺酸钠(PSS)交替沉积在羊毛纤维表面, 赋予其抗菌性. 应用扫描电镜(SEM)考察组装后纤维表面形态, Zeta电位、染色、溶菌酶活性测试研究纤维表面组装机制并考察改性羊毛抗菌效果. SEM结果表明组装后纤维表面粗糙, 部分凹槽被填埋, 证明溶菌酶/PSS自发组装到纤维表面. 表面电位、染料上染量、溶菌酶活力随纤维表面沉积物质不同, 均呈现明显的“层层交替振荡”现象, 证实了组装后纤维表面电荷的交替变化|织物紫外线透过率随组装层数增加呈近似线性降低, 表明溶菌酶在羊毛表面实现了多层组装, 揭示了羊毛纤维表面抗菌功能涂层的层层静电自组装构筑机制. 同时, 组装层数增多, 溶菌酶活性逐渐增大. 载酶羊毛抗菌率达到91.7%, 具有良好的抗菌性能. 相似文献
154.
In this paper, we study the buckling problem of the drifting Laplacian on bounded domains in a complete Riemannian manifold with nonnegative ∞-dimensional Bakry–Émery Ricci curvature. According to the property of the manifold, we obtain a family of trial functions. By making use of these trial functions, we derive a universal inequality of eigenvalues, which is independent of the domains. 相似文献
155.
John A. D. Appleby Xuerong Mao Alexandra Rodkina 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(3):241-269
This paper studies the pathwise asymptotic stability of the zero solution of scalar stochastic differential equation of Itô type. In particular, we provide conditions for solutions to converge to zero at a given rate, which is faster than any exponential rate of decay. The results completely classify the rates of decay of many parameterised families of stochastic differential equations. 相似文献
156.
Shen Y Li S Xie A Xu W Qiu L Yao H Yu X Chen Z 《Colloids and surfaces. B, Biointerfaces》2007,58(2):298-304
The growth of calcium oxalate (CaC2O4) crystal in water channels of three kinds of bicontinuous microemulsions, consisted of P-octyl polyethylene glycol phenylether (OP)/n-amyl alcohol/cyclohexane/water and above microemulsions containing tryptophan (Trp) or aspartic acid (Asp) has been studied. The products were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The results indicated that both surfactant and amino acids all could prompt the growth of calcium oxalate monohydrate (COM) crystal, but the crystal morphology varied with the different microemulsions, pH values of the aqueous solution in channels and concentrations of the reactants. Various crystal morphologies such as butterfly-like, hollow and spiny spherical could be observed easily. A model of molecular identification – organized assembly – pervasion-combination balance was proposed to explain the formation mechanism of CaC2O4 crystals in the microemulsions containing Asp. 相似文献
157.
Xiaoyue Li Alison Gray Xuerong Mao 《Journal of Mathematical Analysis and Applications》2011,376(1):11-28
In this paper, we prove that a stochastic logistic population under regime switching controlled by a Markov chain is either stochastically permanent or extinctive, and we obtain the sufficient and necessary conditions for stochastic permanence and extinction under some assumptions. In the case of stochastic permanence we estimate the limit of the average in time of the sample path of the solution by two constants related to the stationary probability distribution of the Markov chain and the parameters of the subsystems of the population model. Finally, we illustrate our conclusions through two examples. 相似文献
158.
Dong Y Mao X Jiang X Hou J Cheng Y Zhu C 《Chemical communications (Cambridge, England)》2011,47(33):9450-9452
Mg(2+) can lead to the fluorescence enhancement of a dye molecule as high as 47.3-fold while L-proline acts as a promoter in this multicomponent sensory system. The fluorescence color could be easily detected by the naked eye under a UV-lamp. 相似文献
159.
160.
Dr. Yang Wang Dr. Xiaopeng Li Dr. Zhong Huang Dr. Haozhi Wang Dr. Zelin Chen Dr. Jinfeng Zhang Prof. Xuerong Zheng Prof. Yida Deng Prof. Wenbin Hu 《Angewandte Chemie (International ed. in English)》2023,62(6):e202215256
It is vitally important to develop highly active, robust and low-cost transition metal-based electrocatalysts for overall water splitting in neutral solution especially at large current density. In this work, amorphous Mo-doped NiS0.5Se0.5 nanosheets@crystalline NiS0.5Se0.5 nanorods (Am−Mo−NiS0.5Se0.5) was synthesized using a facil one-step strategy. In phosphate buffer saline solution, the Am−Mo−NiS0.5Se0.5 shows tiny overpotentials of 48 and 209 mV for hydrogen evolution reaction (HER), 238 and 514 mV for oxygen evolution reaction (OER) at 10 and 1000 mA cm−2, respectively. Moreover, Am−Mo−NiS0.5Se0.5 delivers excellent stability for at least 300 h without obvious degradation. Theoretical calculations revealed that the Ni sites in the defect-rich amorphous structure of Am−Mo−NiS0.5Se0.5 owns higher electron state density and strengthened the binding energy of H2O, which will optimize H adsorption/desorption energy barriers and reduce the adsorption energy of OER determining step. 相似文献