STUDY ON ELECTRORHEOLOGICAL FLUID DAMPER FOR APPLICATION IN MACHINING CHATTER CONTROL

The electrorheological fluid(ERF)is a kind of intelligent material withbright prospects for industry applications, which has viscoelastic characteristic under the appliedelectric field. The dynamic model of a milling system with an ERF damper is established, and thechaffer suppression mechanism of the ER effect is discussed theoretically. Both the theoreticalstudy and the experimental investigation show that the additional damping and additional stiffnessproduced by the ERF increase with the rise in the strength of electric field E, but their influenceon the cuffing stability is different. Only when both additional damping and additional stiffnesscooperate, the milling chatter can be suppressed quickly and effectively. In additional, an ERFdamper used on the arbor of horizontal spindle milling machine is developed, and a series of millingchatter control experiments are performed. The experimental results show that the milling chaffercan be suppressed effectively by using the ER damper.

安阳市2005年HIV初筛实验考评结果分析

目的:评价安阳市HIV初筛实验室管理现状,为进一步加强全市HIV初筛实验室管理,规范HIV初筛实验室建设和完善HIV检测网络提供参考。方法:采取现场综合考核和发放质控血清现场检测的方式,制定统一考评标准对全市38家待审批HIV初筛实验室进行考评。结果:38家待审批HIV初筛实验室中,3家硬件不符合要求,1家1份样品检测结果不正确,最终34家待审批HIV初筛实验室通过考核颁发合格证书。结论:考评结果显示,我市HIV初筛试验室建设比较规范,HIV检测网络已初步形成,能够满足目前我市HIV检测工作的需要。但初筛实验室工作人员业务素质和技术水平需进一步提高。