Abstract: A method and system for balancing a rotating machinery that operates at or near resonance during its normal operating speed, and which has three separate shafts whose axes of rotations are not aligned along a common axis of rotation and counterweights connected near the ends of each of the shafts. The method includes obtaining speed and vibration data, by mounting velocity transducers on the machine's inner frame and outer casing. A data acquisition system is used to collect and analyze the speed and vibration data for steady state and transient operations. The method further includes adjusting the counterweights using a predetermined rotor influence coefficient determined experimentally using the same setup of transducers, to reduce vibrations below an acceptable level. The data is collected from measurement locations where the number and positions of the measurement locations are less than and different from the number and locations of the correction planes.

Abstract: A plurality of copper lasers, as radiant power sources, emits a beam of power carrying radiation. A plurality of fiber injection assemblies receives power from the plurality of copper lasers and injects such power into a plurality of fibers for individually transmitting the received power to a plurality of power-receiving devices. The power-transmitting fibers of the system are so arranged that power is delivered therethrough to each of the power-receiving devices such that, even if a few of the radiant power sources and/or fibers fail, the power supply to any of the power receiving devices will not completely drop to zero but will drop by the same proportionate amount.

Abstract: A method and apparatus for continuously monitoring a melt surface is provided. The camera includes a CCD detector array, electronic shutter, and associated optical train mounted within a water cooled enclosure, all mounted within close proximity to the melt. Radiation shields surround the enclosure in order to attenuate the heat radiated from the melt to manageable levels. To minimize damage to the electro-optical components of the camera due to melt vapors and other contaminants, the camera enclosure includes a small viewing pinhole through which an inert gas is directed. The pinhole is small enough to minimize the gas flow rate while avoiding noticeable image diffraction. The small pinhole also provides a large depth of field, rendering high quality images of the melt. A compound lens system focuses the image into the CCD array to produce a near diffraction limited image over the angles of interest.

Abstract: A method and apparatus for micromachining and microdrilling which results in a machined part of superior surface quality is provided. The system uses a near diffraction limited, high repetition rate, short pulse length, visible wavelength laser. The laser is combined with a high speed precision tilting mirror and suitable beam shaping optics, thus allowing a large amount of energy to be accurately positioned and scanned on the workpiece. As a result of this system, complicated, high resolution machining patterns can be achieved. A cover plate may be temporarily attached to the workpiece. Then as the workpiece material is vaporized during the machining process, the vapors condense on the cover plate rather than the surface of the workpiece. In order to eliminate cutting rate variations as the cutting direction is varied, a randomly polarized laser beam is utilized. A rotating half-wave plate is used to achieve the random polarization.

Abstract: A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

Abstract: A method and apparatus for producing nanoparticles at a high rate is provided. The system uses two chambers separated by a narrow duct. Contained within the lower chamber is the source material, preferably heated with an electron gun and fed with a continuous feeder for extended nanoparticle production runs. The upper chamber is used to nucleate the nanoparticles, the nanoparticles formed when the source vapor collides with a gas contained within the upper chamber. Depending upon the desired nanoparticles, the gas within the upper chamber is either inert or reactive. The duct connecting the upper and lower chambers is narrow enough to allow differential pumping of the chambers. Furthermore the vapor stream flowing though the duct at high speed provides a pumping action which helps to maintain the differential pressures within the two chambers. At least a portion of the top surface of the upper chamber is cooled, thus providing a condensation site for the nanoparticles.

Abstract: A method and apparatus for achieving improved performance in a solid state laser is provided. A flanged, at least partially undoped end-cap is attached to at least one end of a laserable medium. Preferably flanged, undoped end-caps are attached to both ends of the laserable medium. Due to the low scatter requirements for the interface between the end-caps and the laser rod, a non-adhesive method of bonding is utilized such as optical contacting combined with a subsequent heat treatment of the optically contacted composite. The non-bonded end surfaces of the flanged end-caps are coated with laser cavity coatings appropriate for the lasing wavelength of the laser rod. A cooling jacket, sealably coupled to the flanged end-caps, surrounds the entire length of the laserable medium. Radiation from a pump source is focussed by a lens duct and passed through at least one flanged end-cap into the laser rod.

Abstract: Magnesium fluoride slag contaminated with metallic uranium or uranium compounds is treated by digestion with potassium hydroxide to soluble potassium fluoride and insoluble magnesium hydroxide. The solid and liquid phases are then separated and the solids phase is dissolved in acid to form a solution of metal salts. The liquid phase is treated with lime to precipitate calcium fluoride and convert the potassium back to potassium hydroxide for recycle to the digestion reaction. The metal salts are separated to remove the uranium salt from the magnesium salt. The result is an efficient removal of uranium contamination from the magnesium, the recovery of magnesium in a manner that permits efficient reuse or safe disposal, and the production of calcium fluoride useful for a variety of purposes.

Abstract: Processes for the removal of technetium from contaminated uranium hexafluoride containing technetium, typically as technetium-99 (.sup.99 Tc) in nominal chemical forms are provided. The processes involve contacting the contaminated liquefied uranium hexafluoride with a metal fluoride, typically magnesium fluoride (MgF.sub.2), for a period of time sufficient for the technetium to become adsorbed onto the metal fluoride thereby producing a purified uranium hexafluoride liquid; and removing the purified uranium hexafluoride liquid from the metal fluoride having adsorbed technetium.