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A new scanning transmission electron microscope has been developed for three-dimensional (3D) observations of nanostructures. Using double spherical fulcra, accurate eucentric rotation was achieved. Cylindrical specimens for 3D-observation were prepared by a microsampling technique using a focused ion beam. Copper via-holes of a semiconductor memory device and ZnO particles were observed by the 3D-STEM from different directions, and 3D-data of the ZnO particles were successfully reconstructed in a topography mode.

The paper deals with the method of tool path generation for 5-axis control machining using a ball end mill. 5-axis control machining has been used for aircraft parts as well as for complicated shapes such as mold and dies. However, most of the present CAM systems for 5-axis control machining have limited functions in terms of tool collision, workpiece shapes and machining methods. For that reason, in many cases the optimal cutter location (CL) data cannot be obtained or considerable time is consumed. To solve this problem, we applied a 3-dimensional configuration space (C-Space) and showed the relationship between all tool positions and postures and the existence of tool collision. The method of tool path generation devised in the study enables users to generate CL data reflecting their own machining strategy such as smooth change in tool posture and the state of machining without considering the gouging. The validity of this method was experimentally confirmed by successfully milling an impeller without tool collision occurring.

A physical model of the electric field induced by charged droplets taking account of the effect of space charged droplet emitted from the tip of cone-jet to the external electric field is proposed. Combining this model with the fluid flow equations and charge conservation equation, the evolution of the cone-jet is simulated. The diameter of droplets emitted from the cone-jet tip and current on cone-jet are predicted at various applied voltages and flow rates. The calculated droplet diameter agrees well with experimental measurement. For low conductivity liquid, the droplet diameter decreases with the increment of applied voltage, but decreases with the reduction of flow rate. The simulation result also indicates that the current on the cone-jet increases linearly with the applied voltage. The electric field induced by charged droplets results in the decrease of the cone angle and the presence of space charged droplets has a non-negligible effect on the operation parameters.