Interfacial nanobubbles produced by long-time preserved cold water

Interfacial gaseous nanobubbles which have remarkable properties such as unexpectedly long lifetime and significant potential applications, are drawing more and more attention. However, the recent dispute about the contamination or gas inside the nanobubbles causes a large confusion due to the lack of simple and clean method to produce gas nanobubbles.Here we report a convenient and clean method to effectively produce interfacial nanobubbles based on a pure water system.By adding the cold water cooled at 4℃ for more than 48 h onto highly oriented pyrolytic graphite(HOPG) surface, we find that the average density and total volume of nanobubbles are increased to a high level and mainly dominated by the concentrations of the dissolved gases in cold water. Our findings and methods are crucial and helpful for settling the newly arisen debates on gas nanobubbles.     

一种通用的微波化学合成实验装置

自1986年以来,微波加热应用于化学领域已获得重要进展,与传统加热方法相比,微波加热有许多特点.首先,微波加热是内源性热源,是就地产热方式,与传统上热源均在反应物外 ,热量依靠传导、对流或辐射逐步由表及里传入反应物内部根本不同.微波加热的第二个特点是具有选择性,对各种非极性介质(如多种高分子材料,各种气体)微波很难对它们加热. 因而用这些材料制成的容器,对微波是"透明的",基本不发热,只是容器内的反应物才受微波作用而发热.     

基于IEEE1588协议时钟同步精度影响因素的研究

随着分布式测试技术的快速发展,对地理位置分散的测试设备协同完成测试任务的需求也越来越大,而设备之间的时钟同步精度成为制约测试效果的关键因素;为了对时钟同步精度的影响因素进行研究,提出了基于IEEE1588协议的网络时钟同步实现方案;首先对IEEE1588基本原理进行分析,然后提出了IEEE1588协议的实现方案,最后搭建实验平台对影响同步精度的因素进行研究;研究结果表明,同步间隔和网络拓扑结构影响时钟同步精度的两个主要因素。