摘要:
A system and method according to which a bearing assembly is removed from a casing. In several exemplary embodiments, the bearing assembly is removed from a turbine casing such as, for example, a gas-turbine casing in a jet engine.
摘要:
Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.
摘要:
Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.
摘要:
Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.
摘要:
A discharge lamp system and method of operating a discharge lamp system in which vertical segregation of vapor phase species is reduced. Lamp power is modulated with an arc-straightening frequency and with a frequency that excites a combination radial plus longitudinal acoustic mode of the lamp. The combination radial plus longitudinal acoustic mode may be a combination first radial mode and nth longitudinal acoustic mode and may be excited with a single power frequency or a swept power frequency range. The two frequencies may be provided at the same time, or separately where the modulation at the arc-straightening frequency is 2 to 16 times longer than a subsequent modulation at the combination radial plus longitudinal acoustic mode.
摘要:
A method for producing a superconducting copper oxide based helical resonator coil exhibiting improved quality factor, Q. A copper oxide based superconductor powder is mixed with a binder melt at about 45-65% solids by volume. The binder is an RCOOR' ester wax with R and R' each a long chain hydrocarbon group of at least 6 carbons. The ester wax has a melting point of about 40.degree.-100.degree. C. and a viscosity of about 94-2000 centipoise at its melting point. The binder/powder mixture is extruded and wrapped around a mandrel to form a helical coil. The coil is embedded in a setter powder and heated in an oxidizing atmosphere at up to about 2.degree. C./min to about 450.degree.-650.degree. C., and held for a time sufficient to remove the binder. The coil is then heated in the oxidizing atmosphere at up to about 3.degree. C./min to at least about 920.degree. C., and held at about 920.degree.-990.degree. C. for a time sufficient to achieve a density of at least about 93% of theoretical density. The densified coil is cooled in the oxidizing atmosphere at below about 2.degree. C./min to at or below about 550.degree. C., and annealed at about 450-550.degree. C. in flowing oxygen for a time sufficient to convert the crystal structure of the coil to at least 50 v/o high T.sub.c phase superconducting perovskite crystal. The geometry of the extruded, wrapped helical coil is selected to produce, after subsequent densification, a helical resonator coil about 3-17 mm in inner diameter, of a total length n .lambda./2, wherein n is an integer and .lambda. is the operating wavelength of the helical resonator coil.
摘要:
An arc tube for a high intensity discharge lamp comprising a translucent body defining a discharge space and including spaced-apart electrodes; an arc generating and sustaining medium within the discharge space; and a starting aid contained within the discharge space, the starting aid comprising an electrically conductive stripe formed from a mixture of an electrically conductive material and the high temperature material.
摘要:
Solder paste is deposited using a solder stencil with an aperture having a concave edge in order to reduce the formation of solder balls. The solder deposit may be formed on a pad such that the paste has a concave edge. Solder paste deposits may be made on adjacent pads with the concave surfaces facing one another.