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Corrective Action Investigation Plan for Corrective Action Unit 143: Area 25 Contaminated Waste Dumps, Nevada Test Site, Nevada
None
Date:
July 12, 1999
Creator:
/NV, USDOE
Object Type:
Report
System:
The UNT Digital Library
Evaluation of the Cask Transportation Facility Modifications (CTFM) compliance to DOE order 6430.1A
This report was prepared to evaluate the compliance of Cask Transportation Facility Modifications (CTFM) to DOE Order 6430.1A.
Date:
July 14, 1999
Creator:
ARD, K.E.
Object Type:
Report
System:
The UNT Digital Library
XAF/XANES studies of plutonium-loaded sodalite/glass composite waste forms.
A sodalite/glass ceramic waste form has been developed to immobilize highly radioactive nuclear wastes in chloride form, as part of an electrochemical cleanup process. Simulated waste forms have been fabricated which contain plutonium and are representative of the salt from the electrometallurgical process to recover uranium from spent nuclear fuel. X-ray absorption fine structure spectroscopy (XAFS) and x-ray absorption near-edge spectroscopy (XANES) studies were performed to determine the location, oxidation state and form of the plutonium within these waste forms. Plutonium, in the non-fission-element case, was found to segregate as plutonium(IV) oxide with a crystallite size of at least 20 nm. With fission elements present, the crystallite size was about 2 nm. No plutonium was observed within the sodalite or glass in the waste form.
Date:
July 14, 1999
Creator:
Aase, S. B.; Kropf, A. J.; Lewis, M. A.; Reed, D. T. & Richmann, M. K.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the angular distribution of electrons from W {right arrow} e{nu} decays observed in p pbar collisions at {squareroot}s = 1.8 TeV
We present a preliminary measurement of the electron angular distribution parameter {alpha}<sub>2</sub> in W {yields} e{nu} events using data collected by the D0 detector during the 1994-1995 Tevatron run. We compare our results with next-to- leading order perturbative QCD, which predicts an angular distribution of (1±{alpha}<sub>1</sub> cos{theta}* +{alpha}<sub>2</sub> cos²{theta}*), where {theta}* is the angle between the charged lepton and the antiproton in the Collins-Soper frame. In the presence of QCD corrections, the parameters {alpha}<sub>1</sub> and {alpha}<sub>2</sub> become functions of p<sup>W</sup><sub>T</sub> , the W boson transverse momentum. We present the first measurement of {alpha}<sub>2</sub> as a function of p<sup>W</sup><sub>T</sub>. This measurement is of importance, because it provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W mass measurement.
Date:
July 26, 1999
Creator:
Abbott, B.
Object Type:
Article
System:
The UNT Digital Library
Direct Measurement of A{sub c} using Inclusive Charm Tagging at the SLD Detector
We report a new measurement of A{sub c} using data obtained by SLD in 1993-98. This measurement uses a vertex tag technique, where the selection of a c hemisphere is based on the reconstructed mass of the charm hadron decay vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and the small and stable SLC beams to obtain a high c-event tagging efficiency and purity of 28% and 82%, respectively. Charged kaons identified by the CRID detector and the charge of the reconstructed vertex provide an efficient quark-antiquark tag, with the analyzing power calibrated from the data. We obtain a preliminary result of A{sub c} = 0.603 {+-} 0.028 {+-} 0.023.
Date:
July 14, 1999
Creator:
Abe, K
Object Type:
Report
System:
The UNT Digital Library
New Measurement of A{sub b} at the Z{sup 0} Resonance Using a Vertex Charge Technique
We present a new preliminary measurement of the parity-violation parameter A{sub b} using a self-calibrating vertex-charge technique. In the SLD experiment we observe hadronic decays of Z{sup 0} bosons produced in collisions between longitudinally polarized electrons and unpolarized positrons at the SLAC Linear Collider. A sample of b{bar b} events is selected using the topologically reconstructed mass of B hadrons. From our 1996-1998 data sample of approximately 400,000 hadronic Z{sup 0} decays, we obtain A{sub b} = 0.897 {+-} 0.027(stat){sub -0.034}{sup +0.036}(syst).
Date:
July 20, 1999
Creator:
Abe, K
Object Type:
Report
System:
The UNT Digital Library
Development of a Real-Time Beryllium Air Monitor Utilizing Microwave Induced Plasma Spectroscopy (MIPAES)
This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) Program Development project at the Los Alamos National laboratory (LANL). The focus of this development has been an innovative beryllium air monitor for on-site' real-time continuous monitoring which overcomes limitations of the previous techniques for beryllium monitoring. A bench-top instrument has been set up and the performance of the instrument has been tested based on a solution aerosol. The sensitivity obtained with the instrument is sufficient to ensure workers can respond at airborne levels well below current exposure regulations. With this versatile, real-time monitor, worker exposure can be greatly reduced.
Date:
July 16, 1999
Creator:
Abeln, S.; Duan, Y.-A.; Olivares, J. A.; Koby, M. & Scopsick, R. C.
Object Type:
Report
System:
The UNT Digital Library
MCNP-REN - A Monte Carlo Tool for Neutron Detector Design Without Using the Point Model
The development of neutron detectors makes extensive use of the predictions of detector response through the use of Monte Carlo techniques in conjunction with the point reactor model. Unfortunately, the point reactor model fails to accurately predict detector response in common applications. For this reason, the general Monte Carlo N-Particle code (MCNP) was modified to simulate the pulse streams that would be generated by a neutron detector and normally analyzed by a shift register. This modified code, MCNP - Random Exponentially Distributed Neutron Source (MCNP-REN), along with the Time Analysis Program (TAP) predict neutron detector response without using the point reactor model, making it unnecessary for the user to decide whether or not the assumptions of the point model are met for their application. MCNP-REN is capable of simulating standard neutron coincidence counting as well as neutron multiplicity counting. Measurements of MOX fresh fuel made using the Underwater Coincidence Counter (UWCC) as well as measurements of HEU reactor fuel using the active neutron Research Reactor Fuel Counter (RRFC) are compared with calculations. The method used in MCNP-REN is demonstrated to be fundamentally sound and shown to eliminate the need to use the point model for detector performance predictions.
Date:
July 25, 1999
Creator:
Abhold, M.E. & Baker, M.C.
Object Type:
Article
System:
The UNT Digital Library
Focused Ion Beam Induced Effects on MOS Transistor Parameters
We report on recent studies of the effects of 50 keV focused ion beam (FIB) exposure on MOS transistors. We demonstrate that the changes in value of transistor parameters (such as threshold voltage, V{sub t}) are essentially the same for exposure to a Ga+ ion beam at 30 and 50 keV under the same exposure conditions. We characterize the effects of FIB exposure on test transistors fabricated in both 0.5 {micro}m and 0.225 {micro}m technologies from two different vendors. We report on the effectiveness of overlying metal layers in screening MOS transistors from FIB-induced damage and examine the importance of ion dose rate and the physical dimensions of the exposed area.
Date:
July 28, 1999
Creator:
Abramo, Marsha T.; Antoniou, Nicholas; Campbell, Ann N.; Fleetwood, Daniel M.; Hembree, Charles E.; Jessing, Jeffrey R. et al.
Object Type:
Article
System:
The UNT Digital Library
Angular quadratures for improved transport computations
This paper introduces new octant-range, composite-type Gauss and mid-point rule angular quadrature formulas for neutron and photon transport computations. A generalization to octant-range quadratures is also introduced in order to allow for discontinuities at material interfaces for two- and three-dimensional transport problems which can be modeled with 60-degree triangular or hexagonal mesh subdivisions in the x-y plane.
Date:
July 22, 1999
Creator:
Abu-Shumays, I.K.
Object Type:
Article
System:
The UNT Digital Library
Sensitivity of natural gas HCCI combustion to fuel and operating parameters using detailed kinetic modeling
This paper uses the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to analyze natural gas HCCI combustion in an engine. The HCT code has been modified to better represent the conditions existing inside an engine, including a wall heat transfer correlation. Combustion control and low power output per displacement remain as two of the biggest challenges to obtaining satisfactory performance out of an HCCI engine, and these are addressed in this paper. The paper considers the effect of natural gas composition on HCCI combustion, and then explores three control strategies for HCCI engines: DME (dimethyl ether) addition, intake heating and hot EGR addition. The results show that HCCI combustion is sensitive to natural gas composition, and an active control may be required to compensate for possible changes in composition. The three control strategies being considered have a significant effect in changing the combustion parameters for the engine, and should be able to control HCCI combustion.
Date:
July 19, 1999
Creator:
Aceves, S.; Dibble, R.; Flowers, D.; Smith, J. R. & Westbrook, C. K.
Object Type:
Article
System:
The UNT Digital Library
The Virtual Library in Action
The SLAC Library has for many years provided SPIRES-HEP, a 300,000 record bibliographic database, to the world particle physics community via the Internet as well as through clone sites in Europe and Japan. The 1991 introduction of the e-print archives at LANL coupled with the World-Wide-Web (WWW) from CERN suddenly made it possible to provide easy linkage between bibliographic database records and the actual full-text of papers. The SLAC Library has turned this possibility into reality by converting hundreds of TeX source documents each month into viewable postscript complete with figures. These (now more than 20,000) postscript files are linked to the HEP database, and the full-text is rendered universally visible via WWW. We discuss the project, the collaboration of physicists and librarians, what is easy, what is hard, and our vision for the future.
Date:
July 2, 1999
Creator:
Addis, Louise
Object Type:
Report
System:
The UNT Digital Library
Modeling and Imaging Flexural Plate Wave Devices
Sandia National Laboratories is developing a new form of flexural plate wave device (FPW) for sensor applications. In this device, Lorentz forces cause out of plane vibrations in a silicon nitride membrane. Current induced in transducer lines on the membrane provides information about the amplitude and phase of these surface vibrations. By tracking the large amplitude vibrations that occur at resonant frequencies, it is possible to infer information about loading on the membrane. In fabricating FPWs, it is important to understand the impact that minor defects can have on operation. Through modeling and testing, they are developing resilient designs that provide large amplitude signals with a high tolerance to defects. A finite element model has been developed to perform design trade-off studies, and results from the model are being verified with a unique measurement system that can image Angstrom scale displacements at vibrational frequencies up to 800 kHz. Results from FPW modeling and imaging efforts are presented in this paper.
Date:
July 9, 1999
Creator:
Adkins, D. R.; Butler, M. A.; Chu, A. S. & Schubert, W. K.
Object Type:
Article
System:
The UNT Digital Library
Investigation of Ultrasonic Wave Interaction with Fluid-Saturated Porous Rocks
None
Date:
July 1999
Creator:
Adler, L.
Object Type:
Report
System:
The UNT Digital Library
Using multicast in the global communications infrastructure for group communication
International Monitoring System (IMS) stations and the International Data Centre (IDC) of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization generate data and products that must be transmitted to one or more receivers. The application protocols used to transmit the IMS data and IDC products will be CD-x and IMS-x and the World Wide Web (WWW). These protocols use existing Internet applications and Internet protocols to send their data. The primary Internet applications in use are electronic mail (e-mail) and the file transfer protocol (ftp). The primary Internet communication protocol in use is the Transmission Control Protocol (TCP), which provides reliable delivery to the receiver. These Internet applications and protocol provide unicast (point-to-point) communication. A message sent using unicast has a single recipient; any message intended for more than one recipient must be sent to each recipient individually. In the current design, the IDC and the National Data Centres (NDC's) provide data forwarding to the appropriate receivers. The overhead associated with using unicast to transmit messages to multiple receivers either directly or through a forwarder increases linearly with the number of receivers. In addition, using a forwarding site introduces possible delays and possible points of failure in the path …
Date:
July 30, 1999
Creator:
Agarwal, Deborah A.
Object Type:
Article
System:
The UNT Digital Library
Liquid fuel reformer development.
At Argonne National Laboratory we are developing a process to convert hydrocarbon fuels to a clean hydrogen feed for a fuel cell. The process incorporates a partial oxidation/steam reforming catalyst that can process hydrocarbon feeds at lower temperatures than existing commercial catalysts. We have tested the catalyst with three diesel-type fuels: hexadecane, low-sulfur diesel fuel, and a regular diesel fuel. We achieved complete conversion of the feed to products. Hexadecane yielded products containing 60% hydrogen on a dry, nitrogen-free basis at 800 C. For the two diesel fuels, higher temperatures, >850 C, were required to approach similar levels of hydrogen in the product stream. At 800 C, hydrogen yield of the low sulfur diesel was 32%, while that of the regular diesel was 52%. Residual products in both cases included CO, CO{sub 2}, ethane, ethylene, and methane.
Date:
July 30, 1999
Creator:
Ahmed, S.; Krumpelt, M.; Pereira, C. & Wilkenhoener, R.
Object Type:
Article
System:
The UNT Digital Library
Protected silver coatings for flashlamp-pumped Nd: glass amplifiers
None
Date:
July 1, 1999
Creator:
Ahre, D; Erlandson, A; Farmer, J; Fix, D; Gregg, H; Marshall, C et al.
Object Type:
Article
System:
The UNT Digital Library
Molecular size and structure in pyridine extracts of upper Freeport coal as separated by M41S sieving.
The determination of the structure of coal has long been of interest due to its crucial importance in research on reactivity and processing. However, the chemically and physically heterogeneous nature of coals makes determination of the chemical nature of even the building blocks complicated, since the molecular structure and molecular weight distribution are not dependent on a single molecule or repeat unit as in technical polymers or biopolymers, but on a complex mixture of molecules and potential connections between them which may vary among coals. Coal extracts have long been used to obtain coal material in solution form that can readily be characterized. However, what part of the total coal structure these extracts represent is not completely known. Pyridine has been a particularly good solvent for coal; for example, the extractability of Upper Freeport has been shown to be as high 30%. Although pyridine extracts of coal have been referred to as solutions, there is good evidence that they are not truly solvated, but are dispersions which are polydisperse in particle size. The particle sizes may span the size range from clusters of small molecules (a few {angstrom}) to extended clusters of large particles (a few hundred {angstrom}), not unlike …
Date:
July 2, 1999
Creator:
Ahrens, M.; Hunt, J. E.; Winans, R. E. & Xu, L.
Object Type:
Article
System:
The UNT Digital Library
Overview of small optics for the National Ignition Facility
LLNL's project to construct the National Ignition Facility (NIF), a 192 beam laser system capable of generating enough light energy necessary to achieve fusion ignition, will require 26,641 small optics, many of which will be supplied in the form of cleaned, tested and aligned assemblies. These assemblies will be built to print, cleaned to specifications, and tested to performance specifications, ready to be installed in the laser system. A wide range of potential suppliers will participate in the manufacture of these sophisticated opto-mechanical systems. The injection laser system requires 7,440 precision optical components manufactured to state of the art performance specifications. In addition to 550 aspheric lenses, almost 2,000 precision spherical elements are required. Wave-fronts are specified in terms of P-V, RMS and RMS Gradient wave-front error, with strict requirements on the filtering and resolution which is required. Precision polarizers, high reflectors, leaking mirrors, high damage threshold coatings and cleanliness levels of 50 to 100 are also specified for this section of the NIF laser. The alignment and diagnostics systems for the NIF require 19,201 optics, many of which have requirements that exceed those of the injection laser system. All of these optics will be purchased using the ISO 10110 …
Date:
July 1, 1999
Creator:
Aikens, D & Bissinger, H D
Object Type:
Article
System:
The UNT Digital Library
Implementation of ISO 10110 optics drawing standards for the National Ignition Facility
The National Ignition Facility (NIF) project elected to implement ISO 10110 standard for the specifications of NIF optics drawings in 1996. More than 7,000 NIF large optics and 20,000 NIF small optics will be manufactured based on ISO 10110 indications. ISO 10110 standard meets many of the needs of the NIF optics specifications. It allows the optical engineer to quantify and clearly communicate the desired optical specifications. While no single drawing standard specifies all the requirements of high energy laser system, a combination of ISO 10110 standard with detailed notes make it possible to apply international drawing standards to the NIF laser system. This paper will briefly describe LLNL's interpretation and implementation of the ISO 10110 drawing standard, present some examples of NIF optics drawings, and discuss pros and cons of the indications from the perspective of this application. Emphasis will be given to the surface imperfection specifications, known as 5/, for the NIF optics.
Date:
July 1, 1999
Creator:
Aikens, D M; English, R E & Wang, D Y
Object Type:
Article
System:
The UNT Digital Library
Surface figure and roughness tolerances for NIF optics and the interpretation of the gradient, P-V wavefront and RMS specifications
In a high energy laser system such as the National Ignition Facility (NIF), the ability to focus light into as small a spot as possible at the highest possible fluence is highly dependent on the quality of the optics used in the system. Typically, surface form errors and transmitted and reflected wavefront errors are specified in terms of a peak-to-valley wavefront error (P-V), or occasionally in terms of an RMS wavefront error (RMS) 1 . It has been shown, however, that the parameter that most closely correlates with beam focusability is neither of these, but the RMS of the gradients of the wavefront error (RMS Gradient). Further, the spatial frequency of the wavefront error plays a significant role in the way that a given error effects the performance of the laser system, so careful attention must be paid to how the spatial filtering is both specified and accomplished. Since ISO 10110 has no specific provisions for a gradient specification, LLNL has developed its own notation and procedures for these critical specifications. In evaluating surface figure errors as specified by the NIF drawings, modern phase modulating interferometers (PMI) will be used. In addition to performing QA testing of the optics, LLNL …
Date:
July 1, 1999
Creator:
Aikens, D M; English, R E; House, W; Lawson, J K; Nichols, M A & Whistler, W T
Object Type:
Article
System:
The UNT Digital Library
Diamond Anvils With Integrated Diamond-Encapsulated Microprobes for High-Pressure Electrical Transport Experiments
We have fabricated diamond anvils specially designed for use in ultra-high pressure electrical transport experiments. These anvils, which we refer to as ''designer anvils'', feature thin-film metal microprobes which are encased in a layer of high-quality, epitaxial, chemically vapor deposited (CVD) diamond. The synthetic diamond film ensures that the microprobes are survivable to Mbar pressures, and also serves to electrically insulate the microprobes from the high-pressure gasket. High-pressure resistivity experiments were performed on KI and FeO to pressures of approximately 1.8 and 1.7 Mbars, respectively. Future possible applications of designer anvils are also discussed. [electrical conductivity, synthetic diamond, band overlap, metallization, designer anvils]
Date:
July 21, 1999
Creator:
Akella, J.; Catledge, S. A.; Vohra, Y. K. & Weir, S. T.
Object Type:
Article
System:
The UNT Digital Library
Flexible Allocation of Capacity in Multi-Cell CDMA Networks
This presentation discusses flexible allocation of capacity in multi-cell CDMA networks. The effect of reverse power levels on the capacity of a code-division multiple-access (CDMA) cellular network is evaluated.
Date:
July 1999
Creator:
Akl, Robert G.; Hegde, Manju V.; Naraghi-Pour, Mort & Min, Paul S.
Object Type:
Presentation
System:
The UNT Digital Library
Inclusive Jet Production at CDF
The inclusive jet cross section was measured by CDF at center of mass energies of 1800 and 630 GeV. At {radical}s =1800 GeV, the inclusive jet cross section is compared with NLO QCD predictions (with different sets of parton distribution functions) and with measurement by D0 Collaboration. Strong coupling constant is extracted (as a consistency check) from 1800 GeV inclusive jet data. The ratio of scaled inclusive jet cross sections measured at two values of {radical}s is compared with NLO QCD predictions. Comparison with D0 result is also shown.
Date:
July 20, 1999
Creator:
Akopian, A.
Object Type:
Article
System:
The UNT Digital Library