Novel Thermally Conductive Thermoplastic/Ceramic Composite Foams

Multifunctional materials that are lightweight and thermally conductive but electrically insulating are important for modern electronics, computer, and telecommunication technologies. Here, a novel foam structure of a polymer/matrix composite filled with ceramic platelets with improved thermal conductivity is reported. Such improvement is caused by the stress‐induced alignment of thermally conductive fillers in the cell wall of the plastic foam. The foam structure is very promising for use as a lightweight electronic packaging material owing to its light weight, thermal conduction ability, electrical insulation, and good processability.

     

Effect of [6,6]‐phenyl‐C61‐butyric acid methyl ester on the morphology of poly(3‐hexylthiophene) film

The change of morphology of poly(3‐hexylthiophene) (P3HT) film as a result of blending with [6,6]‐phenyl‐C₆₁‐butyric acid methyl ester (PCBM) was studied using a freeze‐dry method. A porous structure was observed as the P3HT/PCBM solution was freeze‐dried. The pore size decreased as the proportion of PCBM increased in the P3HT/PCBM blended film. Additionally, the freeze‐dried P3HT/PCBM film was more resistant to the formation of PCBM crystals than that prepared by a spin‐coating method during the thermal annealing process. Homogeneous distribution of PCBM in the freeze‐dried P3HT/PCBM film was the main reason for the reduction of large PCBM crystal formation. Copyright © 2011 Society of Chemical Industry     

Synthesis and Characterization of Mesoporous Hypercrosslinked Poly (Styrene Co- Maleic Anhydride) Microspheres

Mesoporous hypercrosslinked styrene and maleic anhydride microspheres were prepared by suspension polymerization using a free radical initiator. Degree of crosslinking was increased by increasing the divinylbenzene content. Scanning electron micrographs revealed the introduction of definite compactness in the microspheres with increase in divinylbenzene content. The crosslinking degree affected the degree of swelling in organic solvents, and was found to be higher with lower concentration of divinylbenzene. Enhanced hydrogen adsorption was observed, indicating the polymer to be a promising material for hydrogen storage.     

Cellular Response of Limbal Stem Cells on Poly (Hydroxybuthyrate-co-Hydroxyvalerate) Porous Scaffolds for Ocular Surface Bioengineering

The aim of this study was to develop a modified-porous poly (3-hydroxybutyrate-co-3- hydroxyvalerate) (PHBV) scaffold for limbal stem cell (LSC) expansion that can serve as a potential alternative substrate to replace human amniotic membrane. The human limbal stem cell was used to evaluate the biocompatibility of substrates (porous scaffold, human amniotic membrane and thermoresponsive substrate) based on their viability, proliferation, and attachment ability. Biocompatibility results indicated that the all substrates were highly biocompatible, as LSCs could favorably attach and proliferate on the scaffold surface. Microscopic figures showed that the human limbal stem cell was firmly anchored to the substrates and were able to retain a normal corneal stem cell phenotype. Microscopic analyses illustrated that cells infiltrated the porous scaffold and successfully formed a three-dimensional corneal epithelium, which was viable for two weeks. Gene expression results revealed no change in the expression profile of LECs grown on scaffold when compared to those grown on human amniotic membrane or thermo responsive substrate. In addition, porous PHBV substrate provides not only a milieu supporting LSCs expansion, but also serve as a useful alternative carrier for ocular surface tissue engineering and could be used as an alternative substrate to amniotic membrane.     

微波陶瓷在高阻带低损耗介质滤波器上的应用研究

研究了ZST系微波陶瓷的组成对介电性能的影响。介绍了用掺入ZnO的ZST系微波陶瓷材料制作高阻带、低损耗介质滤波器的方法;分析了影响滤波器插入衰耗的主要因素。通过对制造的滤波器测试结果表明;其电性能满足设计要求。     

氧化铝陶瓷低温烧结的研究现状和发展前景

本文综述了氧化铝陶瓷低温烧结的研究现状,包括粉体的制备,处理,成型及烧结工艺,并对此领域做了相应的设想和展望。     

多孔介质中流体流动的格子气自动机模拟

介绍了 13-Bit正六边形多速格子气自动机模型的特点 ,讨论了多孔介质流体流动的格子气自动机模型的渗透率等参量算方法 ,应用该模型对计算机产生的多孔介质几何构型和焦炭多孔介质中的流体流动进行了模拟 ,其结果既可以给出多孔介质中的流动细节 ,也可统计得到表征多孔介质宏观流动特征的物理参量 .初步研究表明 :格子气自动机模型可用于模拟复杂边界条件下多孔介质的流体流动     

SrSn_4P_6O_(24)粉料的合成

本研究的目的在于根据NZP[NaZr2 (PO4) 3]晶体化学特性 ,设计出一新的NZP化合物SrSn4P6 O2 4(SSP) ,为二元及多元NZP热膨胀调整提供新的单元组成 .为此 ,本研究采用固相法、共沉淀法及水热法进行了合成实验 ,并做了XRD ,SEM ,TEM及IR光谱检测 .结果表明 :3种方法都能合成SSP ,其中以共沉淀法合成的物相最纯 ,固相法合成的SSP的X射线衍射强度最大 .粉料的颗粒形貌取决于合成条件及合成方法 ,水热法在使用磷酸作矿化剂时获得了单分布形状为正六边形的颗粒 ,物相为单斜相 .使用水和氢氧化钠为矿化剂时 ,颗粒为近似方形及圆形 ,均为NZP相     

铝阳极氧化膜微孔内电沉积超细金属微粒

将铝在磷酸和草酸溶液中用直流和交流阳极氧化,生长多孔氧化膜. 利用这种多孔膜微孔密度大、尺寸细小、结构均匀的特点,将其置于镍盐和钴盐溶液中,电沉积镍、钴和钴磷合金的超细微粒及纤维. 运用TEM配合超薄切片、SAD、EDAX技术和方法,对多孔膜、超细微粒及纤维进行了分析和观测. 所得的超细微粒和纤维是金属,表面有一层薄氧化膜. 镍微粒和纤维由尺寸更细小的微晶组成,而钴趋为单晶体. 磷可通过电沉积加入钴中,但会降低微粒和纤维的生长速度.     

多层陶瓷基板制造技术

采用CuO浆料为布线导体材料是制造多层陶瓷基板的新技术,该方法可彻底除去浆料中的有机物,制造性能良好,易于推广和批量生产的多层陶瓷基板,本文总结了CuO多层陶瓷基板材料及其制造技术,分析了各工艺对基板性能的影响,确定了最佳技术条件。