Fabrication and Characterization of Graphene Based Nanocomposite for Electrical Properties

In the present study, we have described the synthesis of acid functionalized graphene (GE) which was grafted to chitosan (CH) by first reacting the oxidized GE with thionyl chloride to form acyl-chlorinated GE. This product was subsequently dispersed in chitosan and covalently grafted to form GE-chitosan. GE-chitosan was further grafted onto poly(anthranilic acid) (PAA) by free radical polymerization conditions, to yield GE-g-chitosan-g-PAA for our investigations. The structure of GE-CH-PAA composites was characterized by X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), cyclovoltammetrie (CV) and transmission electron microscopy (TEM). XRD report suggested the strongly crystalline character of the specimen prepared. The performance of cycle voltammeter was attributed to the GE-CH-PAA, which provided a large number of active sites and good electrical conductivity. Experimental results suggested that nanocomposites could be combined together for industrial applications.

不同催化剂对聚乙二醇改性油酸产物性能的影响

为提高液压液的稳定性,保障液压支架跟机移架的可靠性,采用聚乙二醇对液压液常用润滑原料油酸进行改性,研究了不同催化剂对改性产物性能的影响。以500 mg/L的人工硬水为配液水,将改性产物按相同质量比各配稀释液,考察稀释液的外观、电导率、Zeta电位、表面张力和平均粒径。实验结果表明,无机和有机强酸分别催化后的产物,在人工硬水中分散性较好,外观呈透亮状态,电导率较人工硬水自身略有提高,表面张力均在40 mN/m以上,表现出良好的亲水能力,平均粒径在30 nm以下,在人工硬水中表现出良好的稳定性。

壳聚糖在柠檬酸溶液中溶解行为研究

采用电位测试法和电导测试法研究壳聚糖在柠檬酸溶液中的溶解行为。即利用电位测试法确定壳聚糖质子化度,利用电导测试法确定壳聚糖溶解于柠檬酸中质子化的作用。结果表明:壳聚糖质子化度α=1.0时,完全溶解;柠檬酸浓度、溶解温度和溶解时间都会影响壳聚糖的溶解,酸浓度的增大、溶解温度的升高和溶解时间的延长都有利于壳聚糖的溶解。壳聚糖存在于柠檬酸溶液中时,溶液性能与其溶解行为密切相关,在一定酸浓度范围内,质子化度达到最大值,有效的解决了壳聚糖的溶解性问题,更好的满足了其在生物医学工程领域的应用要求。

醋酸电离常数测定方法的比较

本文利用同一台仪器的三种电化学功能,选择电导法、p H法、电位滴定法三种不同电化学测定方法,测得醋酸的电离常数,根据测定结果的误差分析,结合操作程序和实验效率,总结出不同测定方法的应用范围,说明了自动电位滴定法测定醋酸电离常数具备准确度高、精密度好、效率高的特点。