Abstract:
An electron emitter comprises field emitter zones formed by projections of field emissive material separated by regions which are not field emissive. An extractor electrode for applying an electric field to the projections and a focus electrode have openings aligned with the emitter zones and material particles aligned with the non-emissive regions. The electrodes form, when suitably energised electron focussing fields to focus electrons emitted from the zones.
Abstract:
A thermionic electron emitter comprises a tube of wall thickness less than 0.1 mm, a body of thermionic electron emissive material compressed and sintered in the tube, and a ring, coaxial with the tube, within the body to provide constraint against cracking of the body.
Abstract:
A thermionic cathode (FIG. 1) comprises a porous matrix of tungsten (4) impregnated with alkaline earth activator.A coating (5) 1 .mu.m thick is formed on the matrix (4). The coating is of .sigma. phase alloy of molybdenum and osmium.Alternative .sigma. phase alloys are disclosed, and various methods of making cathodes are disclosed.
Abstract:
A foliar nutritional composition and method for using same for providing nutrients and/or for treating disease in plants. The foliar nutritional composition comprises a metal salt complexed with amino acids from hydrolyzed yeast extract. The metal salt is selected for high solubility using a salt of a metal selected from the group consisting of copper, nickel, zinc, iron, manganese, and combinations thereof. Preferred metal salt are nitrates, chlorides, and combinations thereof. In the method, an aqueous solution of this composition is sprayed on the plant foliage and absorbed by the plant.
Abstract:
Method and composition for treating citrus canker on citrus plants. The composition comprises copper nitrate complexed with amino acids from hydrolyzed yeast extract. In the method, an aqueous solution of this composition is sprayed on the plant foliage and absorbed by the plant.