Abstract: A reactive torque automatic balancing device for a screw drilling tool includes an upper joint (1); a core cylinder (9) having an inner chamber in communication with the screw drilling tool (305) located downstream, so that drilling fluid from the inner chamber of the upper joint (1) flows to the screw drilling tool (305) through the inner chamber of the core cylinder (9) to allow the screw drilling tool to perform drilling; a lower joint (16) fixedly arranged at a lower end of the core cylinder (9); and an automatic balancing assembly, which is arranged between an outer wall of the core cylinder (9) and an inner wall of the upper joint (1), and driven by hydraulic pressure generated by a part of the drilling fluid flowing through the inner chamber of the upper joint (1).

Abstract: A reactive torque automatic balancing device for a screw drilling tool includes an upper joint (1); a core cylinder (9) having an inner chamber in communication with the screw drilling tool (305) located downstream, so that drilling fluid from the inner chamber of the upper joint (1) flows to the screw drilling tool (305) through the inner chamber of the core cylinder (9) to allow the screw drilling tool to perform drilling; a lower joint (16) fixedly arranged at a lower end of the core cylinder (9); and an automatic balancing assembly, which is arranged between an outer wall of the core cylinder (9) and an inner wall of the upper joint (1), and driven by hydraulic pressure generated by a part of the drilling fluid flowing through the inner chamber of the upper joint (1).

Abstract: Disclosed in the present invention is a pharmaceutical composition, comprising a weight ratio of 1:120 to 1:1000 of camptothecin compound of formula I and ?-cyclodextrin or derivatives thereof, and an acidic buffer to adjust the pH=3.5-6.0. The composition can be used to treat solid tumours, such as melanoma, pancreatic cancer, hepatoma etc. The pharmaceutical composition of the present invention is miscible with a water-miscible co-solvent system in any proportion, and can be used as an intravenous infusion solvent, and has no obvious hemolysis or vascular stimulation; the pharmaceutical composition has a better tumour inhibiting rate than solubilisation of surfactants.