Abstract: The ionization device of the present invention is intended for use in conjunction with an aerosol TOF MS operating in a continuous mode and is capable of ionizing particulated substances in a wide range of particle masses. In the illustrated embodiment, the ionization unit consists of three coaxial cylindrical bodies having a three aligned longitudinal slits for directing electron beams from externally located electron gun onto the axially arranged flow of droplets. The cylindrical bodies are connected to voltage sources so that the external cylindrical body functions as an anode that extracts electrons from the current-heated filament. The central cylindrical body, in combination with the aforementioned anode, serves as an electron-energy control member for precisely controlling and selecting the energy of electrons that reach the flow of particles, while the inner cylindrical body functions as a decelerating member that can be used for adjusting energy of electrons which reached the flow of particles.

Abstract: A method of preparing substantially homogeneous aluminum oxynitride powder and other nitrogen-containing powders is provided. Particularly with respect to the AlON powder, the method comprises the steps of milling a mixture of aluminum and aluminum oxide in a nitrogen-containing atmosphere until a milled powder composed of aluminum-nitrogen solid solution and aluminum oxide forms. The next step is heating the milled powder in the presence of an inert gas and keeping it at sufficient temperature for a sufficient heating time to form the substantially homogenous aluminum oxynitride powder. This method is extended to the preparation of other powders by employing appropriate starting materials. The resultant powders are also claimed as part of the instant invention.