Electrorhcological(ER) fluid is a kind of new promising material.Usually,it consists of a suspension of fine dieleclric particles in a non-conduc-tive base liquid,Its mechanical ch‘1racterislics change rapidly in the prescnce of an applied clectric field,This phenomenon has potential applications in industries and technologics,In the present paper,the studies on ER fluids are reviewed including its physical mechanism mechanical characteristics,materials technology,application and prospects.

In the last ten years research efforts on active vibration control have focused on several important fields ,including control of large spacc structures for reducing vibration, control of large evil structures for comfort and safety,and semi-active isolation for vehicle smooth-going.In this paper the previous studies on these fields of active vibration control are reviewed briefly ,and the current main research work on these field important topics in the theoretical research and the hardware developm...