Abstract: The present invention provides a biopsy rotary cutting device, which comprises a dynamic sealing structure(4) arranged outside an inner cutting cannula(3); the dynamic sealing structure(4) forms a cavity outside the inner cutting cannula(3); the inner cutting cannula(3) comprises a first tube section(31) and a second tube section(32) that are arranged in sequence along the axial direction of the inner cutting cannula(3); the outer diameter of the second tube section(32) is smaller than that of the first tube section(31); a sealing ring(43) is arranged inside the dynamic sealing structure(4); the cavity comprises a first cavity(41) and a second cavity(42); when the inner cutting cannula(3) moves to a first position along its axial direction, the sealing ring(43) is located at the outer side of the second tube section(32); and there is an inter-cavity gap(46) between the sealing ring(43) and the second tube section(32) to realize communication between the first cavity(41) and the second cavity(42).

Abstract: The present invention relates to a kind of microwave cavity for atomic frequency standard, which consists of slotted tube, cylindrical cavity body, dielectric ring, heating filament, screw bolt for adjustment of cavity frequency. Its characteristics are listed as follows: 1. There are slots and electrodes at the upside of slotted tube. 2. The slotted tube and the bottom cap of the cavity are made as a whole. 3. The Rb absorption cell is inserted in the slotted tube. 4. The dielectric ring is inserted between the slotted tube and the cylindrical cavity body. 5. There is one or more screw hole in the wall of cylindrical cavity body. 6. One or more screw bolt for adjustment of cavity frequency is installed into the screw hole.