Abstract: A rotary damper includes an operating part mounted in an interior in a vehicle in such a manner that the operating part can be introduced or withdrawn, an operating part case that guides a path of the operating part, a pinion gear mounted to one side of the operating part and a guide rail rotatably mounted to the operating part case such that the pinion gear can be engaged with the guide rail. Further, a separation preventing protrusion is provided at a portion of the guide rail, where the pinion gear starts to move in a curvilinear form, the separation preventing protrusion configured to support an outside surface of the pinion gear.

Abstract: An apparatus separating a polarizable analyte using dielectrophoresis includes a vessel including a membrane having a plurality of nano- to micro-sized pores, the membrane disposed inside the vessel, electrodes generating spatially non-uniform electric fields in the nano- to micro-sized pores of the membrane when an AC voltage is applied to the electrodes, and a power source applying the AC voltage to the electrodes, wherein a sectional area of the pores varies along a depth of the pores. A method of separating a polarizable material uses the apparatus.