Abstract: An engine assembly includes an air inlet pipe having an air inlet, an air supply port, and an air return port. The air inlet communicates with air. The air supply port communicates with an air inlet manifold of an engine. In a length direction of the air inlet pipe, the air return port is located between the air inlet and the air supply port. An air inlet control valve is disposed on the air inlet pipe, and located between the air inlet and the air return port. An exhaust gas return pipe communicates with the air return port. An exhaust pipe communicates with the exhaust gas return pipe and an exhaust manifold of the engine. In the length direction of the air inlet pipe, a distance S between the air return port and the air inlet control valve and an inner diameter D of the air inlet pipe meet S/D?2.

Abstract: An oil pump is provided. The oil pump comprises: a shell; a rotor mounting part on the shell and having a rotor supporting structure; and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber. A partition wall is disposed between the low-pressure oil chamber and the high-pressure oil chamber for separating the low-pressure oil chamber and the high-pressure oil chamber. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An oil pump is provided. The oil pump comprises a shell, a rotor mounting part on the shell, and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber therein. A buffer chamber is defined between the low-pressure oil chamber and the high-pressure oil chamber, and a barrier wall is disposed between the buffer chamber and the low-pressure oil chamber. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An oil pump is provided. The oil pump comprises a shell, a rotor mounting part disposed at an end of the shell, and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber therein. The high-pressure oil chamber and the low-pressure oil chamber are located at the same side of a periphery of the rotor mounting part. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An oil pump is provided. The oil pump comprises a shell, a rotor mounting part on the shell, and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber therein. A buffer chamber is defined between the low-pressure oil chamber and the high-pressure oil chamber, and a barrier wall is disposed between the buffer chamber and the low-pressure oil chamber. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An oil pump is provided. The oil pump comprises: a shell; a rotor mounting part on the shell and having a rotor supporting structure; and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber. A partition wall is disposed between the low-pressure oil chamber and the high-pressure oil chamber for separating the low-pressure oil chamber and the high-pressure oil chamber. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An oil pump is provided. The oil pump comprises a shell, a rotor mounting part disposed at an end of the shell, and a rotor mechanism disposed on the rotor mounting part. The shell has an inlet and an outlet and defines a low-pressure oil chamber and a high-pressure oil chamber therein. The high-pressure oil chamber and the low-pressure oil chamber are located at the same side of a periphery of the rotor mounting part side. An engine cover comprising the oil pump and an engine comprising the engine cover are also provided.

Abstract: An osmotic pump controlled release tablet and the preparation method thereof are disclosed. The osmotic pump controlled release tablet is composed of tablet core, semipermeable membrane and optional film coating. The material of said semipermeable membrane is composed of ethyl cellulose and povidone in the ratio of 1:1˜1:4 by weight. Said tablet core comprises drug containing layer and push layer. The osmotic pump controlled release tablet also characterizes in that; (1) the angle ?1 formed by the outer curved surface of the drug containing layer and the lateral surface is 120°-180°; and/or (2) the ratio of L1 to r is 0.27-1.0, wherein L1 is the vertical distance from the central vertex of the outer curved surface of the drug containing layer to the plane formed by the intersection line between the outer curved surface of the drug containing layer and the lateral surface, and r is the radius of the tablet core.

Abstract: An osmotic pump controlled release tablet and the preparation method thereof are disclosed. The osmotic pump controlled release tablet is composed of tablet core, semipermeable membrane and optional film coating. The material of said semipermeable membrane is composed of ethyl cellulose and povidone in the ratio of 1:1˜1:4 by weight. Said tablet core comprises drug containing layer and push layer. The osmotic pump controlled release tablet also characterizes in that; (1) the angle ?1 formed by the outer curved surface of the drug containing layer and the lateral surface is 120°-180°; and/or (2) the ratio of L1 to r is 0.27-1.0, wherein L1 is the vertical distance from the central vertex of the outer curved surface of the drug containing layer to the plane formed by the intersection line between the outer curved surface of the drug containing layer and the lateral surface, and r is the radius of the tablet core.

Abstract: A gastroretentive drug delivery system is provided. Said system comprises a hollow vesicle and a drug-containing layer which surrounds the hollow vesicle. Said hollow vesicle preferably has a single chamber structure. The size in maximal diameter direction of said hollow vesicle is preferably 0.5-3.5 cm. The gastroretentive drug delivery system preferably contains an isolating layer and/or waterproofing layer between the hollow vesicle and the layer containing drug.