| 摘要 |
A solid granulated, active bacterial insecticide concentrate prepared with vegetable oil eliminates mosquito larvae. The concentrate has a sand carrier characterized by the following data: 0.8-2 mm average grain size; larger than 1.0, preferably having 1.7 kg/cudm density. The preparation is spread by aerial means over required surface areas by a spreading unit. The unit can be fitted to a dosing tank. The spreader is complete with a drive (2). It also has a centrifugal disc thrower (3) the central axis of which is concentric with the aperture of the dosing shutter (1), and its plane of rotation is perpendicular to the axis. Several 'U' shaped curved scoops (4) are found on the unit's spreading surface. |
