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Rock heat-loss shape factors for Subterrene penetrators

Description: Results of calculations to predict heat losses to surrounding rock for Subterrene rock-melting penetrators of various shapes are presented in nondimensional form that can be applied to a range of axisymmetric penetrator geometries. Theoretical upper and lower limits are placed on a dimensionless time parameter, which includes penetrator dimensions, rock properties, and penetration rate. At these limits, heat losses either approach zero or are unaffected by penetrator geometry and velocity. The estimated heat losses from the nondimensional parameters agree well with experimental data and numerically calculated results. (auth)
Date: October 1, 1973
Creator: Cort, G.E.
Partner: UNT Libraries Government Documents Department

Investigation of internal cavity pressure and thickness response for injection-molded polycarbonates

Description: The internal cavity pressure of an injection mold was evaluated as a controlling variable for the thickness of typical polycarbonate moldings. Mold temperature, melt temperature, and mold-fill mode were evaluated for their effects on molding thickness and thickness runout, designated as the total indicator reading. (TIR). (auth)
Date: November 1, 1973
Creator: Black, P.C.
Partner: UNT Libraries Government Documents Department

Biomedical engineering support. Quarterly progress report, June 15, 1971-- September 15, 1971

Description: A daily power profile for the artificial heart has been determined from the literature and equipment and instrumentation has been assembled for measuring the efficienciea and power losses in the Kwan-Geff antificial heart. (auth)
Date: October 11, 1971
Creator: Kolff, W.J. & Donovan, F.M. Jr.
Partner: UNT Libraries Government Documents Department

Biomedical engineering support. Quarterly progress report, September 15, 1971--December 15, 1971

Description: The power input to the air drive line, input to the air chamber, input to the pumping diaphragm and output from the Kwan-Gett artificial heart has been measured at different atrial pressures with a constant frequency of 120 beats per minute and constant mean arterial pressure of 100 mm Hg. These measurements were made in vitro. The various efficiencies, cardiac outputs and pressures corresponding to the power measurements were also determined. (auth)
Date: December 16, 1971
Creator: Kolff, W.J. & Donovan, F.M. Jr.
Partner: UNT Libraries Government Documents Department

Versatile rock-melting system for the formation of small-diameter horizontal glass-lined holes

Description: Rock-melting penetrators with diameters ranging from 50 mm (2 in.) to 76 mm (3 in.) have reached a stage of development at the Los Alamos Scientific Laboratory (LASL) which suggests that these devices are ready for practical application. Prototype refractory metal penetrators have formed glass-cased vertical holes of 26 m (82 ft) in a single run, and horizontal holes with diameters up to 127 mm (5 in.) are expected in the near future. These small horizontal holes can be used for underground utility conduits; for high-explo sive shot emplacement; and as drainage holes to stabilize road cuts or embankments. Design concepts and preliminary specifications are described for a Subterrene system that forms small-diameter horizontal holes in rock by melting and simultaneously lines the hole with glassy rock melt. Most components of the system are commercially available. Deviation sensors and alignment-control units can be added to ensure that the holes are straight. The design and operation of this Subterrene system are described and proposed development approaches for the hole-forming assembly are discussed. (auth)
Date: October 1, 1973
Creator: Sims, D.L.
Partner: UNT Libraries Government Documents Department

Improvements in hot-wire electroexplosive devices

Description: Several possible design improvements in hot-wire electroexplosive devices were investigated. These were: an arc-resistant header, greater bridgewire-post heat dissipation area, reacting metal bridgewires, and a secondary explosive substitute for primary explosive. Tests using an SE-1 test fixture with four header-bridgewire models showed highly promising results for raising the overall hot-wire ignition safety margins in electrostatic and rf environments without large increases in firing energy. Various electrical characteristics of the four models are given, together with electrical characteristics and function times of the devices loaded with the secondary explosive. (auth)
Date: October 1, 1973
Creator: Joppa, R.M.
Partner: UNT Libraries Government Documents Department

Filler-wire feeder and positioner for electron-beam welding

Description: A filler-wire feeder and positioner device is described for electron- beam welding to provide automatic features that are necessary for efficient wire feeding in a vacuum chamber. The feeder can accommodate as many as nine individual weld passes and is programmed by the use of dial switches. The positioner has three axes of movement, each of which can be controlled from the exterior of the vacuum chamber of the electron-beam welding machine. These area of movement are used to locate, precisely, the wire feed nozzle in relation to the weld joint groove and to raise or lower the nozzle between weld passes. (auth)
Date: February 22, 1974
Creator: Murphy, J.L. & Turner, P.W.
Partner: UNT Libraries Government Documents Department

Solution control for hybrid microcircuit etching

Description: Methods were developed for monitoring the photoresistant developer and gold etchant used in hybrid microcircuit etching. The developer color, which darkens with use, was monitored using a spectrophotometric procedure. The gold concentration in the gold etch was found to be very critical to the etch rate. Measurement of solution density was found to be effective in monitoring the gold concentration. (auth)
Date: October 1, 1973
Creator: Lantz, L.L.
Partner: UNT Libraries Government Documents Department