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Solubility of Anthracene in Binary Alcohol + 2-Methoxyethanol Solvent Mixtures (open access)

Solubility of Anthracene in Binary Alcohol + 2-Methoxyethanol Solvent Mixtures

Article on the solubility of anthracene in binary alcohol + 2-methoxyethanol solvent mixtures.
Date: January 11, 1996
Creator: McHale, Mary E. R.; Powell, Joyce R.; Kauppila, Ann-Sofi M. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Cost effectiveness of silent discharge plasma for point-of-use VOC emissions control in semiconductor fabrication (open access)

Cost effectiveness of silent discharge plasma for point-of-use VOC emissions control in semiconductor fabrication

Extensive research into the treatment and control of Volatile Organic Compounds (VOCs) from semiconductor industry manufacturing processes has identified the need for alternatives to existing combustion devices. Specifically, semiconductor manufacturing design is moving toward the application of effective, small-scale, abatement control technologies for specific point-of-use (POU) waste streams associated with a particular component or manufacturing tool. The consortium of companies involved in semiconductor precompetitive research and development known collectively as SEMATECH recently evaluated eleven emerging environmental technologies designed to treat POU process emissions of VOCs specific to the semiconductor industry. After rigorous technical review only one technology, the Silent Discharge Plasma (SDP) developed at Low Alamos National Laboratory, was considered to successfully meet the required technical performance standards and potential cost effectiveness necessary for continued consideration by SEMATECH in their point-of-use emissions control plans.
Date: December 11, 1996
Creator: Cummings, M. & Booth, S.R.
System: The UNT Digital Library
Applied grinding wheel performance evaluation for optical fabrication (open access)

Applied grinding wheel performance evaluation for optical fabrication

We are collaborating with the Center for Optics Manufacturing (Rochester NY) to develop fine diamond grinding wheels for spherical grinding of glass optics. A standardized method for evaluating wheel performance includes in-process acoustic emission (AE). This paper includes recent AE measurements taken during the evaluation of several fine diamond grinding wheels and discusses how this new information might relate to the physical performance of the wheels. An interesting observation is also reported on the surface topography of worn bronze wheels using an interferometric profiler.
Date: June 11, 1996
Creator: Piscotty, M. A.; Taylor, J. S. & Blaedel, K. L.
System: The UNT Digital Library
Implementation of an acoustic emission proximity detector for use in generating glass optics (open access)

Implementation of an acoustic emission proximity detector for use in generating glass optics

We are using the approach acoustic emission (AE) signal during a grinding operation to detect the proximity of the grinding wheel relative to a brittle material workpiece and are using this detection as a feed- back control signal in our CNC. The repeatability of the AE signal during the wheel approach is the key that allows AE to be used as a proximity detector and is demonstrated at LLNL to be about mm. We noted significant changes of the AE signal as process parameters are modified, but conclude that with a quick CNC calibration routine and holding the parameters constant during a given operation, the AE system can be successfully used to sense pre- contact wheel- to- workpiece separation. Additionally, the AE sensing system allows real- time monitoring during grinding to provide in- process information. The first prototype of an AE system on a commercially available generator is currently be tested at the Center for Optics Manufacturing.
Date: November 11, 1996
Creator: Blaedel, K. L.; Piscotty, M. A. & Taylor, J. S.
System: The UNT Digital Library
High density, high magnetic field concepts for compact fusion reactors (open access)

High density, high magnetic field concepts for compact fusion reactors

One rather discouraging feature of our conventional approaches to fusion energy is that they do not appear to lend themselves to a small reactor for developmental purposes. This is in contrast with the normal evolution of a new technology which typically proceeds to a full scale commercial plant via a set of graduated steps. Accordingly` several concepts concerned with dense plasma fusion systems are being studied theoretically and experimentally. A common aspect is that they employ: (a) high to very high plasma densities ({approximately}10{sup 16}cm{sup -3} to {approximately}10{sup 26}cm{sup -3}) and (b) magnetic fields. If they could be shown to be viable at high fusion Q, they could conceivably lead to compact and inexpensive commercial reactors. At least, their compactness suggests that both proof of principle experiments and development costs will be relatively inexpensive compared with the present conventional approaches. In this paper, the following concepts are considered: (1) The staged Z-pinch, (2) Liner implosion of closed-field-line configurations, (3) Magnetic ``fast`` ignition of inertial fusion targets, (4) The continuous flow Z-pinch.
Date: October 11, 1996
Creator: Perkins, L. J.
System: The UNT Digital Library
Conceptual design for a neutron imaging system for thick target analysis operating in the 10-15 MeV energy range (open access)

Conceptual design for a neutron imaging system for thick target analysis operating in the 10-15 MeV energy range

Fast neutron imaging offers the potential to be a powerful non- destructive inspection tool for evaluating the integrity of thick sealed targets. This is particularly true in cases where one is interested in detecting voids, cracks or other defects in low-Z materials (e.g. plastics, ceramics, salts, etc.) which are shielded by thick, high-Z parts. In this paper we present the conceptual design for a neutron imaging system for use in the 10 - 15 MeV energy range and discuss potential applications in the area of nuclear stockpile steward- ship. The background of this project, currently under development at LLNL, will be outlined and computer simulations will be presented which predict system performance. Efforts to assess technical risks involved in the development of the system will be discussed and the results of a recent experiment designed to evaluate background radiation levels will also be presented.
Date: September 11, 1996
Creator: Dietrich, F.; Hall, J. & Logan, C.
System: The UNT Digital Library
Synthetic strong ground motions for engineering design utilizing empirical Green`s functions (open access)

Synthetic strong ground motions for engineering design utilizing empirical Green`s functions

We present a methodology for developing realistic synthetic strong ground motions for specific sites from specific earthquakes. We analyzed the possible ground motion resulting from a M = 7.25 earthquake that ruptures 82 km of the Hayward fault for a site 1.4 km from the fault in the eastern San Francisco Bay area. We developed a suite of 100 rupture scenarios for the Hayward fault earthquake and computed the corresponding strong ground motion time histories. We synthesized strong ground motion with physics-based solutions of earthquake rupture and applied physical bounds on rupture parameters. By having a suite of rupture scenarios of hazardous earthquakes for a fixed magnitude and identifying the hazard to the site from the statistical distribution of engineering parameters, we introduce a probabilistic component into the deterministic hazard calculation. Engineering parameters of synthesized ground motions agree with those recorded from the 1995 Kobe, Japan and the 1992 Landers, California earthquakes at similar distances and site geologies.
Date: April 11, 1996
Creator: Hutchings, L. J.; Jarpe, S. P.; Kasameyer, P. W. & Foxall, W.
System: The UNT Digital Library
Detecting circumscribed lesions with the Hough transform (open access)

Detecting circumscribed lesions with the Hough transform

We have designed and implemented a circumscribed lesion detection algorithm, based on the Hough Transform, which will detect zero or more approximately circular structures in a mammogram over a range of radii from a few pixels to nearly the size of the breast. We address the geometrical behavior of peaks in Hough parameter space (x,y,r) for both the true radius of a circular structure in the image (r = r{sub o}), and for the parameter r as it passes through this radius. In addition, we evaluate peaks in Hough parameter space by re-analyzing the underlying mammogram in the vicinity of the circular disk indicated by the peak. Discs suggested by the resulting peaks are accumulated in a feature image, scaled by a measure of their quality. These results are then rectified with respect to image contrast extremes and average value. The result is a feature with a continuously scaled pixel level output which suggests the likelihood that a pixel is located inside a circular structure, irrespective of the radius of the structure and overall mammogram contrast. These features are evaluated fast qualitative and quantitative performance metrics which permit circumscribed lesion detection features to be initially evaluated without a full end-to-end …
Date: January 11, 1996
Creator: Groshong, B. R & Kegelmeyer, W. P., Jr.
System: The UNT Digital Library
Forecasting long-range atmospheric pollutant transport and dispersion: Approaches and issues (open access)

Forecasting long-range atmospheric pollutant transport and dispersion: Approaches and issues

The ability to forecast the transport and diffusion of airborne contaminants over long distances is vital when responding to nuclear emergencies. Increases in computing capabilities and ready access to large-scale model output make it possible to employ advanced three-dimensional prognostic models to forecast the long-range transport of toxic or radioactive gases for emergency response. The Savannah River Technology Center (SRTC) of the U.S. Department of Energy`s Savannah River Site demonstrated this during the European Tracer EXperiment (ETEX). ETEX, conducted in the Fall of 1994, is designed to evaluate the performance of models for long-range atmospheric pollutant transport and dispersion. ETEX involved two tracer experiments as well as a multinational real-time modeling exercise. The real-time modeling component tested the ability of participants to provide timely long-range forecasts of the tracer plume transport and diffusion. Notification of the time, location and amount of tracer occurred after the start of the release. Participants provided 60-hour forecasts of tracer surface concentration within 6 hours of being notified, and updated forecasts every 12 hours thereafter. The two tracer experiments were conducted near Rennes, France on October 23, 1994 and November 14, 1994.
Date: January 11, 1996
Creator: Griggs, D. P. & Addis, R. P.
System: The UNT Digital Library
Holledge gauge failure testing using concurrent information processing algorithm (open access)

Holledge gauge failure testing using concurrent information processing algorithm

For several decades, computerized information processing systems and human information processing models have developed with a good deal of mutual influence. Any comprehensive psychology text in this decade uses terms that originated in the computer industry, such as ``cache`` and ``memory``, to describe human information processing. Likewise, many engineers today are using ``artificial intelligence``and ``artificial neural network`` computing tools that originated as models of human thought to solve industrial problems. This paper concerns a recently developed human information processing model, called ``concurrent information processing`` (CIP), and a related set of computing tools for solving industrial problems. The problem of focus is adaptive gauge monitoring; the application is pneumatic pressure repeaters (Holledge gauges) used to measure liquid level and density in the Defense Waste Processing Facility and the Integrated DWPF Melter System.
Date: April 11, 1996
Creator: Weeks, G. E.; Daniel, W. E.; Edwards, R. E.; Jannarone, R. J.; Joshi, S. N.; Palakodety, S. S. et al.
System: The UNT Digital Library
Isolated prompt photon cross sections (open access)

Isolated prompt photon cross sections

We show that the conventionally defined partonic cross section for the production of isolated prompt photons is not an infrared safe quantity. We work out the case of {ital e}{sup +}{ital e}{sup -} {r_arrow} {gamma} + {Chi}, and discuss implications for hadron reactions.
Date: September 11, 1996
Creator: Berger, E. L.; Guo, Xiaofeng & Qiu, Jianwei
System: The UNT Digital Library
High-Resolution Superconducting X-Ray Spectrometers With an Active Area of 282 μm x 282 μm (open access)

High-Resolution Superconducting X-Ray Spectrometers With an Active Area of 282 μm x 282 μm

Superconducting tunnel junctions coupled to superconducting absorbers may be used as high-resolution, high-efficiency X-ray spectrometers. We have tested devices with niobium X-ray absorbing layers coupled to aluminum layers that serve as quasiparticle traps. In this work we measured the current pulses from a large area tunnel junction using an amplifier based on an array of 100 SQUIDs. Using this amplifier and a 282 micron X 282 micron junction, we have measured an energy resolution of 19 eV FWHM for 1.5 keV X rays and 21 eV for 2.6 keV X rays. The area of this junction is eight times the area of any junction previously measured to have such high energy resolution.
Date: September 11, 1996
Creator: Mears, C. A.; Labov, S. E.; Frank, M.; Netel, H.; Hiller, L. J.; Lindeman, M. A. et al.
System: The UNT Digital Library
Developing inertial fusion energy - Where do we go from here? (open access)

Developing inertial fusion energy - Where do we go from here?

Development of inertial fusion energy (IFE) will require continued R&D in target physics, driver technology, target production and delivery systems, and chamber technologies. It will also require the integration of these technologies in tests and engineering demonstrations of increasing capability and complexity. Development needs in each of these areas are discussed. It is shown how IFE development will leverage off the DOE Defense Programs funded inertial confinement fusion (ICF) work.
Date: June 11, 1996
Creator: Meier, W. R. & Logan, G.
System: The UNT Digital Library
RK-TBA prototype RF source (open access)

RK-TBA prototype RF source

A prototype rf power source based on the Relativistic Klystron Two-Beam Accelerator (RK-TBA) concept is being constructed at the Lawrence Berkeley National Laboratory to study physics, engineering, and costing issues. The prototype is described and compared to a full scale design appropriate for driving the Next Linear Collider (NLC). Specific details of the induction core tests and pulsed power system are presented. The 1-MeV, 1.2-kA induction gun currently under construction is also described in detail.
Date: April 11, 1996
Creator: Houck, T.; Anderson, D. & Giordano, G.
System: The UNT Digital Library
Cesium determination for the DWPF off-gas system performance test (open access)

Cesium determination for the DWPF off-gas system performance test

In an effort to determine the cesium decontamination factors (DF`s) of the Defense Waste Processing Facility (DWPF) melter off-gas system at the Savannah River Site, the system was verified during an off-gas performance test. The off-gas performance test occurred during the DWPF waste Qualification Campaigns, WP-16 and WP-17. The verification of the off-gas system, which eliminated the need for a startup test involving a radioactive cesium addition, was based on the analysis of nonradioactive cesium across the first and second stage High Efficiency Particulate Air (HEPA) filters. The amount of cesium on the first and second stage HEPA filters was determined by leaching samples from each HEPA filter with nitric acid and analyzing the leachate using Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). The ICP-MS method has been demonstrated to be sufficiently sensitive to measure small quantities of cesium on filters. Based on the cesium results of the HEPA filter, cesium DF`s were calculated. The DF`s indicated that the DWPF HEPA filters performed better than the design basis. In addition to the HEPA filters, a determination of the cesium concentration in the melter feed, the canister glass and the off-gas condensate was made. These analyses provided information on cesium flow …
Date: April 11, 1996
Creator: Andrews, M.K.; Elder, H.H. & Boyce, W.T.
System: The UNT Digital Library
Coresident sensor fusion and compression using the wavelet transform (open access)

Coresident sensor fusion and compression using the wavelet transform

Imagery from coresident sensor platforms, such as unmanned aerial vehicles, can be combined using, multiresolution decomposition of the sensor images by means of the two-dimensional wavelet transform. The wavelet approach uses the combination of spatial/spectral information at multiple scales to create a fused image. This can be done in both an ad hoc or model-based approach. We compare results from commercial ``fusion`` software and the ad hoc, wavelet approach. Results show the wavelet approach outperforms the commercial algorithms and also supports efficient compression of the fused image.
Date: March 11, 1996
Creator: Yocky, David A.
System: The UNT Digital Library
Comparison of non-thermal plasma techniques for abatement of volatile organic compounds and nitrogen oxides (open access)

Comparison of non-thermal plasma techniques for abatement of volatile organic compounds and nitrogen oxides

Non-thermal plasma processing is an emerging technology for the abatement of dilute concentrations of volatile organic compounds (VOCs), nitrogen oxides (NO{sub x}) and other hazardous air pollutants (HAPs) in atmospheric-pressure gas streams. Either electrical discharge or electron beam methods can produce these plasmas. Recent laboratory-scale experiments show that the electron beam method is remarkably more energy efficient than competing non-thermal plasma techniques based on pulsed corona and other types of electrical discharge plasma. Preliminary cost analysis based on these data also show that the electron beam method may be cost-competitive to thermal and catalytic methods that employ heat recovery or hybrid techniques.
Date: January 11, 1996
Creator: Penetrante, B. M.; Hsiao, M. C. & Bardsley, J. N.
System: The UNT Digital Library
Aerogel derived catalysts (open access)

Aerogel derived catalysts

Aerogels area class of colloidal materials which have high surface areas and abundant mesoporous structure. SiO{sub 2} aerogels show unique physical, optical and structural properties. When catalytic metals are incorporated in the aerogel framework, the potential exists for new and very effective catalysts for industrial processes. Three applications of these metal-containing SiO{sub 2} aerogels as catalysts are briefly reviewed in this paper--NO{sub x} reduction, volatile organic compound destruction, and partial oxidation of methane.
Date: December 11, 1996
Creator: Reynolds, J. G., LLNL
System: The UNT Digital Library
Declassified reports show Holocaust began in 1941 on Soviet soil (open access)

Declassified reports show Holocaust began in 1941 on Soviet soil

Newspaper article from The Houston Chronicle, discussing new evidence uncovered about the beginning of the Holocaust in 1941.
Date: November 11, 1996
Creator: Dobbs, Michael
System: The Portal to Texas History
[Obituary for Mayne S. Kopisch] (open access)

[Obituary for Mayne S. Kopisch]

Obituary for Mayne S. Kopisch of Temple, Texas, printed in the Temple Daily Telegram.
Date: April 11, 1996
Creator: unknown
System: The Portal to Texas History