Nafion-graphene nanocomposite film as enhanced sensing platform for ultrasensitive determination of cadmium

In this work, an ultrasensitive platform for the detection of cadmium (Cd2+) combining the nafion-graphene nanocomposite film with differential pulse anodic stripping voltammetry (DPASV) analysis was presented. It is found that this sensing platform exhibits enhanced response to the determination of the Cd2+ and has been used to determine the Cd2+ in real sample with good recovery.

Electrogenerated chemiluminescence sensing platform using Ru(bpy)(3)(2+) doped silica nanoparticles and carbon nanotubes

An effective electrogenerated chemiluminescence (ECL) sensor was developed by coimmobilization of the Ru(bpy)(2)(3+)-doped silica (RuDS) nanoparticles and carbon nanotubes (CNTs) on glassy carbon electrode through hydrophobic interaction. The uniform RuDS nanoparticles were prepared by a water-in-oil (W/O) microemulsion method and Ru(bpy)(3)(2+) doped inside could still maintain its high ECL efficiency. With such unique immobilization method, a great deal of Ru(bpy)(3)(2+) was immobilized three-dimensionally on the electrode , which could greatly enhance the ECL response and result in the increased sensitivity. On the other hand, CNTs played dual roles as matrix to immobilize RuDS nanoparticles and promoter to accelerate the electron transfer between Ru(bpy)(3)(2+) and the electrode. The as-prepared ECL sensor displayed good sensitivity and stability.

Intra-habitat heterogeneity of microbial food web structure under the regime of eutrophication and sediment resuspension in the large subtropical shallow Lake Taihu, China

Planktonic microbial community structure and classical food web were investigated in the large shallow eutrophic Lake Taihu (2338 km(2), mean depth 1.9 m) located in subtropical Southeast China. The water column of the lake was sampled biweekly at two sites located 22 km apart over a period of twelve month. Site 1 is under the regime of heavy eutrophication while Site 2 is governed by wind-driven sediment resuspension. Within-lake comparison indicates that phosphorus enrichment resulted in increased abundance of microbial components. However, the coupling between total phosphorus and abundance of microbial components was different between the two sites. Much stronger coupling was observed at Site 1 than at Site 2. The weak coupling at Site 2 was mainly caused by strong sediment resuspension, which limited growth of phytoplankton and, consequently, growth of bacterioplankton and other microbial components. High percentages of attached bacteria, which were strongly correlated with the biomass of phytoplankton, especially Microcystis spp., were found at Site 1 during summer and early autumn, but no such correlation was observed at Site 2. This potentially leads to differences in carbon flow through microbial food web at different locations. Overall, significant heterogeneity of microbial food web structure between the two sites was observed. Site-specific differences in nutrient enrichment (i.e. nitrogen and phosphorus) and sediment resuspension were identified as driving forces of the observed intra-habitat differences in food web structure.

Corrosion fatigue of welded joints of steel for marine platform

Experiments on the corrosion fatigue behaviour of welded joints of the steel for marine platform in air and seawater, and of the joints in seawater with cathodic protection, yielded data for linear regression to obtain fatigue life curves (Delta S-N-f). The laws of corrosion fatigue in welded joints of test steel are discussed with reference to those of A(587) and A(131) steel. In these experiments, the fatigue damage occurring at all welded joints around the weld interface resulted in the cracks and fractures. The fatigue life of the specimens in seawater with cathodic protection is longer than that in seawater Without protection.

基于web的遥操作系统时延分析

采用预测控制算法给出了一种带有时延补偿器的新的控制结构,分别在前向通道和反馈通道设计补偿器对网络时延进行补偿.实验结果表明:带有预测器及补偿器的新的控制结构可以改善系统的动态性能,并且能够保证系统在具有时延和数据丢失的环境下的稳定性.

基于Petri网的Web数据库访问的建模研究

本文针对多用户访问Web数据库的过程进行了分析并提出改进思路,然后利用带抑止弧的扩充Petri网对改进后的访问过程进行建模。

基于web的远程控制机器人研究

Internet连接了全球的计算机 ,它为人们提供了分享数据、图片、影像甚至实时影像的机会 ,但与远程地点的真实交互还是离不开象机器人这样的智能设备 .Web技术与机器人控制技术的结合 ,促成了基于 web的远程控制机器人概念的诞生 .本文将就基于 web的远程控制机器人的发展历程、研究现状、主要技术与实现、发展趋势及应用前景等做综合的介绍 .

基于WEB支持的市场客户管理系统的设计

本文阐述了采用Ｉｎｔｅｒｎｅｔ／Ｉｎｔｒａｎｅｔ技术和利用ＡＳＰ实现数据的动态发布技术以及基于分布网络环境下的异地设计与制造技术，设计了基于ｗｅｂ的支持机器人异地设计制造的市场客户管理系统，从而探讨了Ｂｒｏｗｓｅｒ／Ｓｅｒｖｅｒ结构的数据库发布系统的设计方法。

虚拟企业支撑平台系统的设计

虚拟企业(或曰动态企业联盟)是目前公认的增强企业竞争力、对多变的全球市场进行快速反应的有效途径,受到普遍关注。目前对虚拟企业技术的研究大多在模型以及支撑技术等方面,面向中小企业的虚拟企业构建支撑平台还没有得到应有的重视,然而这却是影响虚拟企业技术走向实用的关键。本文在研究了基于INTERNET/WEB虚拟企业模型基础上,深入研究了虚拟企业生命周期中各阶段的工作内容和特点,提出了基于WEB的虚拟企业全生命周期支撑平台的系统概念和体系结构;同时详细介绍了我们开发的面向制造企业的虚拟企业生命周期的支撑平台系统-VESS。VESS将为我国制造企业快速构建自己的虚拟企业提供系统支撑。

Web数据挖掘的原理、方法及用途

Web数据挖掘是将数据挖掘技术和理论应用于对WWW资源进行挖掘的一个新兴的研究领域,本文介绍了Web数据挖掘的基本概念,分类,并给出 Web数据挖掘的基本原理,基本方法,最后指出 Web数据挖掘的用途,展望了其美好的发展前景。