一类Hammerstein积分方程的正分歧点

本文考虑有序Banach空间中形如x(t)=∫_Gk(t,s)[λAx(s) f(s,x(s),λ)]ds的Hammerstein型积分方程,给出了此类方程存在正分歧点的某些充分条件。     

Banking behaviour after the lifecycle event of “moving in together”: An exploratory study of the role of marketing investments

This study addresses an important issue for both managers and researchers: whether it is advantageous for financial services providers to invest in youth marketing. More specifically, the effectiveness of these investments is evaluated in terms of retention proneness once youngsters enter the lifecycle event of “moving in together”. The study identifies eight constructs of youth marketing and contrasts their impact against the best deal when youngsters decide to move in together and consequently experience the need to buy their first collectivized financial products, such as a joint account or a mortgage for their new home. Furthermore, the influence of the partner, prior patronage behaviour, customer demographics and psychographic variables are tested for. The findings of the study reveal that: (i) individuals are likely to change their banking behaviour during crucial lifetime events such as moving in together, (ii) not all youth marketing investments are equally effective, while (iii) the best deal components (e.g. convenience, price conditions, etc.) have a major impact.     

Applicability of classical methods of pore size analysis for MCM-41 and SBA-15 silicas

Two most popular ordered mesoporous silicas, MCM-41 and SBA-15, exhibiting uniform mesopores of approximately cylindrical shapes, have been used as model adsorbents for verification, improvement and/or development of adsorption-based methods for characterization nanoporous materials. While the applicability of the classical methods for pore size analysis was widely examined by employing MCM-41 materials, the large-pore materials such as SBA-15 did not find adequate usage for this type of studies. The current work addresses the issue of applicability of classical methods such as Barrett-Joyner-Hallenda (BJH) and Broekhoff-de Boer (BdB) methods for pore size analysis of mesoporous silicas by using MCM-41 and SBA-15 materials as model adsorbents. In addition, the Kruk-Jaroniec-Sayari (KJS) method, which is based on the BJH algorithm and experimental relations for the pore width and statistical film thickness, is discussed too. While the MCM-41 materials cover the range of small mesopores (about 2-7 nm), the inclusion of SBA-15 materials allowed us to examine the range of the pore diameters up to about 12 nm. The high quality MCM-41 and SBA-15 samples are used to discuss the applicability and limitations of the aforementioned characterization methods and to propose some recommendations for pore size analysis of these materials.     

Synthesis of highly ordered nanopores on alumina by two-step anodization process

Highly ordered anodic alumina was produced, on RF sputtered aluminium on a conductive glass substrate, by two step anodizing process in 0.4 M sulphuric acid at constant cell potentials of between 5 and 25 V and at a constant current density of 20 mA cm⁻². The temperature was kept constant at 15 °C during both anodization processes. The effects of the anodizing potential, current density, and time on the pore diameters were established. Longer anodization periods result in wider irregular pores with reduced porosity for both constant potential and constant current density anodization processes. The current density increases with increasing constant anodizing potential and generally remains constant with time after a sharp rise. Potential drop during constant current density anodization behaves in a similar manner. We confirm that sulphuric acid has a self-ordering potential of 25 V above which burning occurs.     

胆固醇(Cholesterol)嵌入卵磷脂(PC)有序体后对其中CaCO3晶型结构的影响

在PC和Chol/PC有序体中进行CaCO₃沉淀反应,用X射线衍射和扫描电镜方法表征了反应物结构,研究了作为有机模板剂的不同分子有序体对CaCO₃的晶型和形态的指导作用.在反胶束合成中出纳米级CaCO₃颗粒.胆固醇对有序体有显著影响,进而影响此体系中形成的CaCO₃晶型,可诱导生成3种CaCO₃异构体:胶体CaCO₃、球霰石和方解石.方解石含量随胆固醇含量增加减少.     

弱交换富足序半群(Ⅰ)

本文将序半群上的 Ｇｒｅｅｎ’ｓ－关系推广为 Ｇｒｅｅｎ’ｓ＊一关系．给出主序（左、右）＊－理想、主序＊－滤特征描述和弱交换富足序半群的特征．用这些特征证明了一类弱交换富足序半群的结构定理：若序半群Ｓ满足 ,则Ｓ是弱交换富足序半群当且仅当Ｓ是左（右）单序半群｛（ｅ）（Ｓ）｝的半格．     

Banach空间中不连续非线性Volterra型积分方程的唯一解

本文在一般序Ｂａｎａｃｈ空间中研究了不连续非线性Ｖｏｌｔｅｒｒａ型积分方程的唯一解．在非常弱的条件下证明了非线性Ｖｏｌｔｅｒｒａ型积分方程的唯一解可以由迭代序列的一致极限得到,并给出了逼近解的迭代序列的误差估计式,然后应用到一阶微分方程的初值问题,本质改进并推广了最近的一些结果．     

非线性算子方程迭代解的存在性定理及其应用

在Ｂａｎａｃｈ空间中,利用锥理论和单调迭代方法研究了一类非线性算子方程的解和最小最大耦合解的存在与迭代逼近定理,并应用到Ｂａｎａｃｈ空间中非线性Ｖｏｌｔｅｒｒａ型积分方程和常微分方程的初值问题．     

线性空间中向量极值问题的最优性条件

文 [1]建立了线性拓扑空间中向量极值问题的广义 Kuhn- Tucker条件和 L agrange乘子存在定理 .本文将在线性空间中讨论这方面问题 ,首先在线性空间中建立了次似凸向量值映射的择一定理 ,进而得出序线性空间中向量极值问题的最优性条件及其标量化定理 .     

Studying the mechanism of ordered growth of InAs quantum dots on GaAs/InP

We study the mechanism of ordered growth of InAs quantum dots (islands) on a GaAs/InP substrate in theory and point out that the tensile strain can be used to control InAs/InP self-assembled quantum dots arrangement. Photoluminescence spectrum, and atomic force microscopy images have been investigated. In the experiment, ordered InAs islands have been obtained and the maximum density of quantum dots is 1.6×10¹⁰ cm⁻² at 4 monolayers InAs layer.