摘要:
A method of controlling deflection of a charged particle beam in an electrostatic lens includes establishing a symmetrical electrostatic lens configuration comprising a plurality of electrodes disposed at unadjusted positions that are symmetric with respect to the central ray trajectory with applied unadjusted voltages that create fields symmetric with respect to the central ray trajectory. A symmetric electric field is calculated corresponding to the set of unadjusted voltages. A plurality of lower electrodes is arranged at adjusted positions that are asymmetric with respect to the central ray trajectory. A set of adjusted voltages is obtained for the plurality of lower electrodes, wherein the set of adjusted voltages corresponds to a set of respective potentials of the symmetric electric field at respective adjusted asymmetric positions. The adjusted voltages are applied to the asymmetric lens configuration when the charged particle beam passes therethrough.
摘要:
A method of controlling deflection of a charged particle beam in an electrostatic lens includes establishing a symmetrical electrostatic lens configuration comprising a plurality of electrodes disposed at unadjusted positions that are symmetric with respect to the central ray trajectory with applied unadjusted voltages that create fields symmetric with respect to the central ray trajectory. A symmetric electric field is calculated corresponding to the set of unadjusted voltages. A plurality of lower electrodes is arranged at adjusted positions that are asymmetric with respect to the central ray trajectory. A set of adjusted voltages is obtained for the plurality of lower electrodes, wherein the set of adjusted voltages corresponds to a set of respective potentials of the symmetric electric field at respective adjusted asymmetric positions. The adjusted voltages are applied to the asymmetric lens configuration when the charged particle beam passes therethrough.
摘要:
A technique for shaping a ribbon-shaped ion beam is disclosed. In one particular exemplary embodiment, the technique may be realized as an apparatus for shaping a ribbon-shaped ion beam. The apparatus may comprise an electrostatic lens having a substantially rectangular aperture for a ribbon-shaped ion beam to pass through, wherein a plurality of focusing elements are positioned along short edges of the aperture, and wherein each focusing element is separately biased and oriented to shape the ribbon-shaped ion beam.
摘要:
A removable belt-backing mechanism (50) is provided for a hand-held endless loop belt sander (2). The belt-backing mechanism (50) includes an attachment bracket (52), which slidably cooperates with a pair of slots (66, 68) to provide a removable connection to the sander. A plate (70) is movably connected to the attachment bracket (52) by a set of pins (72, 74, 76, 78), and is biased toward the inside surface of the sanding belt (26) by a set of springs (96, 98) to provide a flat sanding area for sanding planar surfaces.
摘要:
The impregnation of carbon with nitrite compounds drastically reduces the formation of acetylene and carbon dioxide in the adsorptive recovery of vinyl chloride monomer from air-contaminated streams containing such monomer.
摘要:
A belt sander attachment (2) is disclosed for a portable drill or the like (4), for sanding curved or flat surfaces. A frame (6) has a drive roller (8) and an idle roller (10) mounted thereto together with a movable carriage (22) carrying a second idle roller (24). The attachment includes belt changing locking means (78) for holding the carriage in a retracted position against the bias of belt tensioning biasing springs (32, 34). A positive belt tracking system (40) is provided for laterally adjusting the carriage relative to longitudinal belt movement around the rollers, to enable proper alignment and positive tracking under differing conditions. A belt tracking tray (70) is mounted to the carriage. A combined guard plate and pressure guide (54) enables guidance and application of sanding pressure by the user in a convenient orientation.
摘要:
A method for decomposing halogenated organic compounds which comprises: (a) preheating the halogenated organic compound to a temperature above about 300.degree. C. and (b) contacting the preheated organic compound with a platinum catalyst in the presence of an oxidizing agent at a temperature of at least 350.degree. C. The process converts the major part of the halide in the organic halide to hydrogen halide.