Abstract: A calibration method for an oxygen sensor and a medical ventilation system are disclosed. At least two electrical signals are acquired at two time points within a preset time period, when the oxygen sensor is in a preset oxygen concentration. A response function of the oxygen sensor which corresponds to the preset oxygen concentration, is determined according to the at least two time points and the at least two electrical signals. A steady-state output value of the oxygen sensor in the preset oxygen concentration is determined, according to the response function and a characteristic curve of the oxygen sensor is determined, according to the steady-state output value of the oxygen sensor in the preset oxygen concentration. The described method reduces the time waiting for the oxygen sensor to respond, thus improving calibration efficiency, and facilitating the improvement of the oxygen concentration monitoring accuracy of a ventilation device in daily use.

Abstract: A multilayer water pipe for mining operations has an outer layer and an inner layer. The inner layer of the multilayer water pipe includes a composition containing a poly(phenylene ether), a hydrogenated block copolymer of an alkenyl aromatic monomer and a conjugated diene, optionally, a homopolystyrene, a rubber-modified polystyrene, or a combination comprising at least one of the foregoing, and a flame retardant comprising an organophosphate ester. The outer layer of the multilayer water pipe includes a composition containing a high density polyethylene, an antistatic agent, a flame retardant, and a flame retardant synergist. The multilayer water pipe exhibits a desirable balance of impact strength, tensile strength, burst pressure resistance, static pressure resistance, flame retardancy, and outer surface electrical resistance.

Abstract: A multilayer water pipe for mining operations has an outer layer and an inner layer. The inner layer of the multilayer water pipe includes a composition containing a poly(phenylene ether), a hydrogenated block copolymer of an alkenyl aromatic monomer and a conjugated diene, optionally, a homopolystyrene, a rubber-modified polystyrene, or a combination comprising at least one of the foregoing, and a flame retardant comprising an organophosphate ester. The outer layer of the multilayer water pipe includes a composition containing a high density polyethylene, an antistatic agent, a flame retardant, and a flame retardant synergist. The multilayer water pipe exhibits a desirable balance of impact strength, tensile strength, burst pressure resistance, static pressure resistance, flame retardancy, and outer surface electrical resistance.

Abstract: A water pipe for mining operations has an outer diameter of 20 to 200 millimeters and a wall thickness of 2 to 20 millimeters. The water pipe includes a composition containing 58 to 82 parts by weight poly(phenylene ether), 8 to 18 parts by weight of a hydrogenated block copolymer of an alkenyl aromatic monomer and a conjugated diene, 0 to 15 parts by weight of polystyrene selected from the group consisting of homopolystyrenes, rubber-modified polystyrenes, and combinations thereof, and 10 to 20 parts by weight of a flame retardant comprising an organophosphate ester, wherein parts by weight values are based on 100 parts by weight total of the poly(phenylene ether), the hydrogenated block copolymer, the polystyrene, and the flame retardant. The water pipe exhibits a desirable balance of impact strength, tensile strength, burst pressure resistance, static pressure resistance, and flame retardancy.

Abstract: A water pipe for mining operations has an outer diameter of 20 to 200 millimeters and a wall thickness of 2 to 20 millimeters. The water pipe includes a composition containing 58 to 82 parts by weight poly(phenylene ether), 8 to 18 parts by weight of a hydrogenated block copolymer of an alkenyl aromatic monomer and a conjugated diene, 0 to 15 parts by weight of polystyrene selected from the group consisting of homopolystyrenes, rubber-modified polystyrenes, and combinations thereof, and 10 to 20 parts by weight of a flame retardant comprising an organophosphate ester, wherein parts by weight values are based on 100 parts by weight total of the poly(phenylene ether), the hydrogenated block copolymer, the polystyrene, and the flame retardant. The water pipe exhibits a desirable balance of impact strength, tensile strength, burst pressure resistance, static pressure resistance, and flame retardancy.