纳米银/聚丙烯酰胺/乙烯-醋酸乙烯酯共聚物复合材料的电性能

Nano-Ag particles/polyacrylamide （PAM） composites were synthesized by γ irradiation method and then blended with ethylene vinyl acetate （EVA）. Dielectric behaviors of the Ag/PAM/EVA composites are investigated as a function of both the concentration and size of Ag particles. When concentration of the Ag fillers is rarely low, dielectric anomalies were first observed in contrast to the traditional percolation theory. As concentration of Ag increases, volume resistivity and breakdown field strength are enhanced, loss tangent （tan δ） reduced and dielectric constant kept invariable. In addition, the above variation became larger when the diameter of the Ag nano-particles is smaller. Such dielectric anomalies may be understood by considering the unique ＂Coulomb Blockade Effect＂ of the nano-sized Ag particles.     

用于乙醇-水分离的SA-PVA/PSF中空纤维渗透汽化复合膜

Using polysulfone (PSF) hollow fiber ultrafiltration membranes as the substrate, sodium alginate (SA) and polyvinyl alcohol (PVA) blend solutions as the coating solution, and maleic anhydride (MAC) as the cross-linked agent, SAPVA/PSF hollow fiber composite membranes were prepared for the dehydration of ethanol-water. The effects of different sodium alginate concentration in the coating solutions and different operating temperatures on pervaporation performance were investigated. The experimental results showed that pervaporation performance of the SA-PVA/PSF composite membranes for ethanol-water solution exhibited a high separation factor although they had a relatively low permeation flux. As SA concentration in SA-PVA coating solution was 66.7% and the operating temperature was 40 ℃, SA-PVA/PSF hollow fiber composite membrane (PS4) had a separation factor of 886 and flux of 12.6 g/(m2·h). Besides, SA-PVA/PSF hollow fiber composite membranes (PS3 and PS4) were used for the investigation of the effect of ethanol concentration in the feed solution on pervaporation performance.     

一类高维非线性椭圆型方程正整解的存在性

以Shauder-Tychonoff不动点定理为工具,建立一类高维非线性椭圆型方程△u=f（x,△↓u）u^y（x∈R^n,n≥3,0〈y〈1）正的整体解的存在性定理,并给出了解的有关性质．     

Meta—Lindeloef空间的性质

对meta—Lindeloef空间的性质进行了探讨．给出了X是meta—Lindeloef空间的一个等价条件：X的每一开覆盖哑都有点可数的加细覆盖。E使对每一个x∈X,x∈Int（st（z,v））;证明了meta—Lindeloef空间被可数对一开映射保持;在可分空间中meta—Lindeloef空间与Lindeloef空间等价．     

广义度量空间中几种映射的关系

主要讨论了序列覆盖的伪开映射与几乎开映射之间的关系,也讨论了在第一可数空间中与序列覆盖映射等价的几个条件,以及由定理得出的几个推论．     

多值Φ-强伪压缩映像不动点的集合序列的Ishikawa迭代逼近

在一致光滑的实Banach空间中,研究多值Φ强伪压缩映像集合序列生成的Ishikawa迭代序列逼近问题,给出了迭代集合序列逼近多值Φ强伪压缩映像不动点集合的强收敛定理,是Ishikawa迭代序列逼近多值Φ强伪压缩映像不动点问题的推广。     

散体材料桩和水泥桩复合地基固结理论研究综述

复合地基在地基处理中具有十分重要的地位,其用于加固地基,增强地基承载力和减小地基沉降具有良好的效果,因而在工程中被广泛采用。由于研究复合地基的固结是研究复合地基加固机理的主要内容之一,土体的固结直接影响复合地基的变形和承载能力。因此,有必要对复合地基的固结理论进行全面、系统地认识。本文主要对散体材料桩和水泥桩复合地基的固结理论进行综述,阐述了复合地基固结理论研究的现状和取得的理论成果。     

凸模糊映射次微分的性质

引入模糊数空间中凸模糊映射和模糊数导概念,定义了凸模糊映射循环单调映射的概念,找到并证明了多个凸模糊映射次微分的性质。     

隐喻、转喻机制下的英语一词多义现象

一词多义是一种重要的语言现象,主要通过隐喻和转喻来实现。隐喻和转喻不仅是修辞手段,而且是两种重要的词义延伸的方式。隐喻以事物间的相似性为基础由源域向目的域映射,转喻以相邻性和突显性为基础在同一个域内实现事物间的映射。隐喻和转喻并不是截然对立的。