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Base hydrolysis and supercritical water oxidation of PBX-9404 (open access)

Base hydrolysis and supercritical water oxidation of PBX-9404

Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The authors also examine products from the subsequent hydrothermal treatment of the base hydrolysate. The gases produced from hydrolysis of PBX-9404 are ammonia, nitrous oxide, and nitrogen. Major aqueous products are sodium formate, acetate, nitrate, and nitrite, but not all carbon products have been identified. Hydrothermal processing of base hydrolysate destroyed up to 98% of the organic carbon in solution, and higher destruction efficiencies are possible. Major gas products detected from hydrothermal processing were nitrogen and nitrous oxide.
Date: November 9, 1994
Creator: Flesner, R. L.; Spontarelli, T.; Dell`Orco, P. C.; Kramer, J. F. & Sanchez, J. A.
System: The UNT Digital Library
An approximate algorithm for the flux from a rectangular volume source (open access)

An approximate algorithm for the flux from a rectangular volume source

An exact semi-analytic formula for the flux from a rectangular surface source with a slab shield has been derived and the required function table has been calculated. This formula is the basis for an algorithm which gives a good approximation for the flux from a rectangular volume source. No other hand calculation method for this source geometry is available in the literature.
Date: November 9, 1994
Creator: Wallace, O. J.
System: The UNT Digital Library
New applications of copper vapor lasers in micromachining (open access)

New applications of copper vapor lasers in micromachining

We have developed a copper vapor laser based micromachinig system using advanced beam quality control and precision wavefront tilting technologies. Precision microdrilling has been demonstrated through percussion drilling and trepanning using this system. With a 30-W copper vapor from running at multi-kHz pulse repetition frequency, straight parallel holes with size varying from 500 microns to less than 25 microns and with aspect ratio up to 1:40 have been consistently drilled with good surface finish on a variety of metals. Micromilling and microdrilling on ceramics using a 250-W copper vapor laser have also been demonstrated with good result. Materialographic sections of machined parts show little (submicron scale) recast layer and heat affected zone.
Date: November 9, 1994
Creator: Chang, J. J.; Martinez, M. W.; Warner, B. E.; Dragon, E. P.; Huete, G. & Solarski, M. E.
System: The UNT Digital Library
Multiple-beam pulse shaping and preamplification (open access)

Multiple-beam pulse shaping and preamplification

Glass fusion laser systems typically use a master oscillator-power amplifier (MOPA) architecture, where control of the optical pulse temporal and spatial parameters is accomplished mainly in the master oscillator and low power optics. The pulses from this low power ``front end`` are amplified in the power amplifier, which modifies the pulse shape temporally and spatially. Nonlinear frequency conversion crystals following the amplifier further change the pulse before it reaches the target. To effectively control the optical pulse on target for different types of experiments, and compensate for nonlinearity in the preceding optics, the front end system must be versatile enough to easily control many pulse parameters over a large range. The front end pulse generation system described in this article represents a new approach to this problem. The proposed National Ignition Facility (NIF) has 192 beamlines, each of which requires an input pulse of up to 12 Joules in around 4 ns equivalent square pulse length. Considerations of laser architecture for supplying each of these beamlines from a central oscillator system were crucial in the design of the front end. Previous lasers have used bulk optics to split a single oscillator signal and report beams to multiple amplifier chains. A …
Date: November 9, 1994
Creator: Wilcox, R. B.; VanWonterghem, B. W.; Burkhart, S. C. & Davin, J. M.
System: The UNT Digital Library