Abstract: The present invention relates to a method for grafting a surface of a medical device by using quaternized trimethylamine. A catheter onto which quaternized trimethylamine has been grafted allows for the reduction of thrombus production. Therefore, the catheter having quaternized trimethylamine grafted thereto exhibits the effect of repressing thrombus production and enhancing the function of inhibiting blood adsorption and blood cell adsorption.

Abstract: An agent is used to treat waste water containing dimethylsulfoxide and includes a solution of a porous material at a concentration of 6500 to 7500 mg/L, where an average size of pore openings of the porous material in a range of 60–550 ?m. The agent may be used in an aeration tank of a waste water treatment system, where the aeration tank is connected to a waste water tank for collecting waste water containing dimethylsulfoxide. A sedimentation tank of the system is connected to the aeration tank via a connection pipe for biologically decomposing the dimethylsulfoxide and settling sludge produced therein, and a treated water tank of the system returns a portion of treated waste water to the waste water tank and collects the remaining treated water therein.

Abstract: An agent is used to treat waste water containing dimethylsulfoxide and includes a solution of a porous material at a concentration of 6500 to 7500 mg/L, where an average size of pore openings of the porous material in a range of 60-550 &mgr;m. The agent may be used in an aeration tank of a waste water treatment system, where the aeration tank is connected to a waste water tank for collecting waste water containing dimethylsulfoxide. A sedimentation tank of the system is connected to the aeration tank via a connection pipe for biologically decomposing the dimethylsulfoxide and settling sludge produced therein, and a treated water tank of the system returns a portion of treated waste water to the waste water tank and collects the remaining treated water therein.