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Results:
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Results from an FPIX0 chip bump-bonded to an atlas pixel detector
Results are presented of tests performed on the first pixel detector readout ASIC designed at Fermilab (FPIX0).
Date:
October 1, 1998
Creator:
A. Mekkaoui, D. Christian, S. Kwan, J Srage and R. Yarema
Object Type:
Article
System:
The UNT Digital Library
Expected Harmonics (Version 1.0) in BNL-built LHC Dipoles
None
Date:
January 1, 1998
Creator:
A., Jain
Object Type:
Report
System:
The UNT Digital Library
Advanced Emissions Control Development Program
The objective of the Advanced Emissions Control Development Program (AECDP) is to develop practical, cost-effective strategies for reducing the emissions of air toxics from coal-fired boilers. Ideally, the project aim is to effectively control air toxic emissions through the use of conventional flue gas cleanup equipment such as electrostatic precipitators (ESPS), fabric filters (baghouse), and wet flue gas desulfurization. Development work to date has concentrated on the capture of mercury, other trace metals, fine particulate and hydrogen chloride. Following the construction and evaluation of a representative air toxics test facility in Phase I, Phase II focused on the evaluation of mercury and several other air toxics emissions. The AECDP is jointly funded by the United States Department of Energy's Federal Energy Technology Center (DOE), the Ohio Coal Development Office within the Ohio Department of Development (oCDO), and Babcock& Wilcox-a McDermott company (B&W).
Date:
April 1, 1998
Creator:
A.P.Evans; Redinger, K.E. & Holmes, M.J.
Object Type:
Report
System:
The UNT Digital Library
GEOTHERMAL HEAT PUMP GROUTING MATERIALS
The thermal conductivity of cementitious grouts has been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. The cement-sand grouts were also tested for rheological characteristics, bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the thermal conductivity, permeability, bonding and exotherm data for selected cementitious grouts. The theoretical reduction in bore length that could be achieved with the BNL-developed cement-sand grouts is examined. Finally, the FY 98 research and field trials are discussed.
Date:
April 1, 1998
Creator:
ALLAN,M.
Object Type:
Article
System:
The UNT Digital Library
THERMAL CONDUCTIVITY AND OTHER PROPERTIES OF CEMENTITIOUS GROUTS
The thermal conductivity and other properties cementitious grouts have been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. In addition to thermal conductivity, the cementitious grouts were also tested for bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the results for selected grout mixes. Relatively high thermal conductivities were obtained and this leads to reduction in predicted bore length and installation costs. Improvements in shrinkage resistance and bonding were achieved.
Date:
May 1, 1998
Creator:
ALLAN,M.
Object Type:
Article
System:
The UNT Digital Library
Quasifree (e,e'p) Reactions and Proton Propagation in Nuclei
The (e,e'p) reaction was studies on targets of C, Fe, and Au at momentum transfers squared Q{sup 2} of 0.6, 1.3, 1.8 and 3.3 GeV{sup 2} in a region of kinematics dominated by quasifree electron-proton scattering. Missing energy and missing momentum distributions are reasonably well described by plane wave impulse approximation calculations with Q{sup 2} and A dependent corrections that measure the attenuation of the final state protons.
Date:
June 1, 1998
Creator:
Abbott, David; Ahmidouch, A.; Amatuni, Ts. A.; Armstrong, C.; Arrington, J.; Assamagan, J. A. et al.
Object Type:
Article
System:
The UNT Digital Library
An automated vacuum gauge calibration system
An automated system for calibrating vacuum gauges over the pressure range of 10{sup {minus}6} to 0.1 Pa was designed and constructed at the National Institute of Standards and Technology (NIST) for the Department of Energy (DOE) Primary Standards Laboratory at Sandia National Laboratories (SNL). Calculable pressures are generated by passing a known flow of gas through an orifice of known conductance. The orifice conductance is derived from dimensional measurements and accurate flows are generated using metal capillary leaks. The expanded uncertainty (k = 2) in the generated pressure is estimated to be between 1% and 4% over the calibration range. The design, calibration results. and component uncertainties will be discussed.
Date:
April 1, 1998
Creator:
Abbott, P. J. & Benner, M. S.
Object Type:
Article
System:
The UNT Digital Library
The calculation of satellite line structures in highly stripped plasmas
This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Recently developed high-resolution x-ray spectrographs have made it possible to measure satellite structures from various plasma sources with great detail. These lines are weak optically thin lines caused by the decay of dielectronic states and generally accompany the resonance lines of H-like and He-like ions. The Los Alamos atomic physics and kinetics codes provide a unique capability for calculating the position and intensities of such lines. These programs have been used to interpret such highly resolved spectral measurements from pulsed power devices and laser produced plasmas. Some of these experiments were performed at the LANL Bright Source and Trident laser facilities. The satellite structures are compared with calculations to diagnose temperatures and densities. The effect of non-thermal electron distributions of electrons on calculated spectra was also considered. Collaborations with Russian scientists have added tremendous value to this research die to their vast experience in x-ray spectroscopy.
Date:
November 1, 1998
Creator:
Abdallah, J. Jr.; Kilcrease, D. P.; Faenov, A. Ya. & Pikuz, T. A.
Object Type:
Report
System:
The UNT Digital Library
Optimal choice of cupola furnace nominal operating point
One of the main goals in the operation of a cupola furnace is to keep the molten iron properties within prescribed bounds while maintaining the most economical operation for the cupola. In this paper the authors present a procedure to obtain the nominal values for the manipulated process variables. The nominal values are calculated by solving a constrained nonlinear programming optimization problem. Two different optimization problems are discussed and examples for using the procedure are presented.
Date:
August 1, 1998
Creator:
Abdelrahman, M.A. & Moore, K.L.
Object Type:
Article
System:
The UNT Digital Library
Design characteristics for facilities which process hazardous particulate
Los Alamos National Laboratory is establishing a research and processing capability for beryllium. The unique properties of beryllium, including light weight, rigidity, thermal conductivity, heat capacity, and nuclear properties make it critical to a number of US defense and aerospace programs. Concomitant with the unique engineering properties are the health hazards associated with processing beryllium in a particulate form and the potential for worker inhalation of aerosolized beryllium. Beryllium has the lowest airborne standard for worker protection compared to all other nonradioactive metals by more than an order of magnitude. This paper describes the design characteristics of the new beryllium facility at Los Alamos as they relate to protection of the workforce. Design characteristics to be reviewed include; facility layout, support systems to minimize aerosol exposure and spread, and detailed review of the ventilation system design for general room air cleanliness and extraction of particulate at the source.
Date:
December 1, 1998
Creator:
Abeln, S.P.; Creek, K. & Salisbury, S.
Object Type:
Article
System:
The UNT Digital Library
Laser barometer
This paper describes an invention of a pressure measuring instrument which uses laser radiation to sense the pressure in an enclosed environment by means of measuring the change in refractive index of a gas - which is pressure dependent.
Date:
April 1, 1998
Creator:
Abercrombie, K.R.; Shiels, D. & Rash, T.
Object Type:
Patent
System:
The UNT Digital Library
Comparison of ICl- and IBr-Based Plasma Chemistries for Inductively Coupled Plasma Etching of GaN, InN and AlN
A parametric study of the etch characteristics of GaN, AIN and InN has been earned out with IC1/Ar and IBr/Ar chemistries in an Inductively Coupled Plasma discharge. The etch rates of InN and AIN were relatively independent of plasma composition, while GaN showed increased etch rates with interhalogen concentration. Etch rates for all materials increased with increasing rf chuck power, indicating that higher ion bombardment energies are more efficient in enhancing sputter resorption of etch products. The etch rates increased for source powers up to 500 W and remained relatively thereafter for all materials, while GaN and InN showed maximum etch rates with increasing pressure. The etched GaN showed extremely smooth surfaces, which were somewhat better with IBr/Ar than with IC1/Ar. Maximum selectivities of- 14 for InN over GaN and >25 for InN over AIN were obtained with both chemistries.
Date:
December 1, 1998
Creator:
Abernathy, C.R.; Cho, H.; Donovan, S.M.; Hahn, Y.B.; Han, J.; Hays, D.C. et al.
Object Type:
Article
System:
The UNT Digital Library
U.S./Russian cooperative efforts to enhance nuclear MPC&A at VNIITF, (Chelyabinsk-70)
The All Russian Scientific Research Institute of Technical Physics (VNIITF) is one of the major sites in the nuclear weapons complex in Russia. The site contains a number of research facilities which use nuclear material as well as assembly, disassembly, and testing of prototypes (pilot samples) of nuclear weapons. VNIITF also has ties to the major nuclear materials production facilities in the Urals region of Russia. The objective of the U.S./Russian Materials Protection Control and Accounting (MPC&A) cooperative program between the US Department of Energy and Russia�s Ministry of Atomic Eneryy, at VNIITF is to improve the protection and accountability of nuclear material at VNIITF. Enhanced safeguards systems have been implemented at a reactor test area called the Pulse Research Reactor Facility (PRR) in Area 20. The area contains three pulse reactors with associated storage areas. The integrated MPC&A system at the PRR was demonstrated to US and Russian audiences in May, 1998. Expansion of work into several new facilities is underway both in Area 20 and at other locations. These include processing and production facilities some of which are considered sensitive facilities, by the Russian side. Methods have been developed to assure that work is done as agreed without …
Date:
September 1, 1998
Creator:
Abramson, B.; Apt, K.; Blasy, J.; Bukin, D.; Churikov, Y.; Eras, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Drying behavior of K-East canister sludge
A series of tests were conducted by Pacific Northwest National Laboratory to evaluate the drying behavior of sludge taken from the Hanford K-East Basin storage canisters. Some of the components of K-Basin sludge, such as oxides of uranium and its hydrates, could be associated with the spent nuclear fuel that will ultimately be loaded into Multi-Canister Overpacks (MCOs) and transferred to interim dry storage on the Hanford Site. The materials sealed in the MCOs must be compatible with the storage facility safety basis and the design accident analyses. Understanding the drying behavior of hydrates that may be formed by the reaction of uranium oxides (corrosion products) and water will help ensure these criteria are addressed. Drying measurements of sludge samples collected from K-East Basin canisters showed the water content (physically plus chemically bound) to range between 5 wt% and 75 wt%. Uranium oxide hydrates, the main source of gaseous products that can pressurize the MCOs during storage, constituted about 3 wt% to 15 wt% of the total water content of the initial weight. Most of the physically bound water was assumed to be released from the samples at ambient temperature when the system was pumped down to vacuum conditions of …
Date:
May 1, 1998
Creator:
Abrefah, J.; Buchanan, H. C. & Marschman, S. C.
Object Type:
Report
System:
The UNT Digital Library
Oxidation rate of K-Basin spent nuclear fuel in moist air
Experiments have been conducted by Pacific Northwest National Laboratory to determine the oxidation rate of damaged/corroded N-Reactor fuel material in moist air. Five SNF pieces (with regular geometrical shapes) sectioned from a damaged element stored in the K-West Basin were oxidized in flowing air containing moisture. The SNF oxidation behavior in moist air at a temperature of 198 C can best be fitted by parabolic oxidation kinetics. A linear rate equation gave the best fit to the oxidation data at 250 C and above. The results within the temperature range studied, therefore, show a transition from parabolic oxidation kinetics to linear oxidation kinetics. The transition temperature is somewhere between 198 C and 250 C. The tests at approximately 300 C gave results that were very different from the other tests at temperatures of 198 C, 250 C, and 349 C. The SNF sample weight change at this temperature showed erratic behavior. Visual examination indicated the sample fragmented into small pieces and powder as a result of rapid oxidation and hydration. Additional tests at temperatures close to 300 C (i.e., 300 {+-} 10 C) are recommended in order to fully understand the oxidation behavior of the damaged/corroded SNF samples in moist …
Date:
June 1, 1998
Creator:
Abrefah, J.; Buchanan, H. C. & Marschman, S. C.
Object Type:
Report
System:
The UNT Digital Library
Dry air oxidation kinetics of K-Basin spent nuclear fuel
The safety and process analyses of the proposed Integrated Process Strategy (IPS) to move the N-Reactor spent nuclear fuel (SNF) stored at K-Basin to an interim storage facility require information about the oxidation behavior of the metallic uranium. Limited experiments have been performed on the oxidation reaction of SNF samples taken from an N-Reactor outer fuel element in various atmospheres. This report discusses studies on the oxidation behavior of SNF using two independent experimental systems: (1) a tube furnace with a flowing gas mixture of 2% oxygen/98% argon; and (2) a thermogravimetric system for dry air oxidation.
Date:
June 1, 1998
Creator:
Abrefah, J.; Buchanan, H. C.; Gerry, W. M.; Gray, W. J. & Marschman, S. C.
Object Type:
Report
System:
The UNT Digital Library
Drying results of K-Basin fuel element 3128W (run 2)
An N-Reactor outer fuel element that had been stored underwater in the Hanford 100 Area K-East Basin was subjected to a combination of low- and high-temperature vacuum drying treatments. These studies are part of a series of tests being conducted by Pacific Northwest National Laboratory on the drying behavior of N-Reactor spent nuclear fuel elements removed from both the K-West and K-East Basins. The drying test series was designed to test fuel elements that ranged from intact to severely damaged. The fuel element discussed in this report was removed from an open K-East canister (3128W) during the first fuel selection campaign conducted in 1995, and has remained in wet storage in the Postirradiation Testing Laboratory (PTL, 327 Building) since that time. Although it was judged to be breached during in-basin (i.e., K-Basin) examinations, visual inspection of this fuel element in the hot cell indicated that it was likely intact. Some scratches on the coating covering the cladding were identified before the furnace test. The drying test was conducted in the Whole Element Furnace Testing System located in G-Cell within the PTL. This test system is composed of three basic systems: the in-cell furnace equipment, the system gas loop, and the …
Date:
July 1, 1998
Creator:
Abrefah, J.; Klinger, G. S.; Oliver, B. M.; Marshman, S. C.; MacFarlan, P. J.; Ritter, G. A. et al.
Object Type:
Report
System:
The UNT Digital Library
Examination of the surface coating removed from K-East Basin fuel elements
This report provides the results of studies conducted on coatings discovered on the surfaces of some N-Reactor spent nuclear fuel (SNF) elements stored at the Hanford K-East Basin. These elements had been removed from the canisters and visually examined in-basin during FY 1996 as part of a series of characterization tests. The characterization tests are being performed to support the Integrated Process Strategy developed to package, dry, transport, and store the SNF in an interim storage facility on the Hanford site. Samples of coating materials were removed from K-East canister elements 2350E and 2540E, which had been sent, along with nine other elements, to the Postirradiation Testing Laboratory (327 Building) for further characterization following the in-basin examinations. These coating samples were evaluated by Pacific Northwest National Laboratory using various analytical methods. This report is part of the overall studies to determine the drying behavior of corrosion products associated with the K-Basin fuel elements. Altogether, five samples of coating materials were analyzed. These analyses suggest that hydration of the coating materials could be an additional source of moisture in the Multi-Canister Overpacks being used to contain the fuel for storage.
Date:
May 1, 1998
Creator:
Abrefah, J.; Marschman, S.C. & Jenson, E.D.
Object Type:
Report
System:
The UNT Digital Library
The migration and entrapment of DNAPLs in physically and chemically heterogeneous porous media. 1998 annual progress report
'The migration and entrapment of dense nonaqueous phase liquids (DNAPLs) at hazardous waste sites is typically believed to be controlled by physical heterogeneities. This belief is based upon the assumption that permeability and capillary properties are determined by soil texture. These transport properties however, also depend on porous media wettability characteristics, which may vary spatially in a formation due to variations in aqueous phase chemistry, contaminant aging, and/or variations in mineralogy and organic matter distributions. The overall objective of this research is to investigate the influence of such coupled physical and chemical heterogeneities on the migration and entrapment of DNAPLs in the saturated zone. This research includes laboratory and numerical investigations for a matrix of organic contaminants and solid media encompassing a range of wettability characteristics. Specific objectives include: (1) quantification of system wettability and interfacial tensions; (2) determination of transport property relations; (3) two-dimensional infiltration experiments; (4) modification of a continuum based multiphase flow simulator to account for physical heterogeneity, saturation independent and saturation dependent wettability, and concentration dependent wettability and interfacial tension; and (5) utilization of this model to explore the potential influence of coupled physical and chemical heterogeneities on the migration of DNAPLs and the development of …
Date:
June 1, 1998
Creator:
Abriola, L.M. & Demond, A.H.
Object Type:
Report
System:
The UNT Digital Library
Tropical Western Pacific site science mission plan. Semiannual project report, January--June 1998
The Department of Energy`s Atmospheric Radiation Measurement (ARM) program was created in 1989 as part of the US Global Change Research Program to improve the treatment of atmospheric radiative and cloud processes in computer models used to predict climate change. The overall goal of the ARM program is to develop and test parameterizations of important atmospheric processes, particularly cloud and radiative processes, for use in atmospheric models. This goal is being achieved through a combination of field measurements and modeling studies. Three primary locales were chosen for extensive field measurement facilities. These are the Southern Great Plains (SGP) of the United States, the Tropical Western Pacific (TWP), and the North Slope of Alaska and Adjacent Arctic Ocean (NSA/AAO). This Site Science Mission Plan [RPT(TWP)-010.000] describes the ARM program in the Tropical Western Pacific locale.
Date:
November 1, 1998
Creator:
Ackerman, T.; Mather, J.; Clements, W. & Barnes, F.
Object Type:
Report
System:
The UNT Digital Library
Classification of behavior using unsupervised temporal neural networks
Adding recurrent connections to unsupervised neural networks used for clustering creates a temporal neural network which clusters a sequence of inputs as they appear over time. The model presented combines the Jordan architecture with the unsupervised learning technique Adaptive Resonance Theory, Fuzzy ART. The combination yields a neural network capable of quickly clustering sequential pattern sequences as the sequences are generated. The applicability of the architecture is illustrated through a facility monitoring problem.
Date:
March 1, 1998
Creator:
Adair, K.L. & Argo, P.
Object Type:
Article
System:
The UNT Digital Library
Rural electrification: Waste biomass Russian northern territories. Final report
The primary objective of this pre-feasibility evaluation is to examine the economic and technical feasibility of replacing distillate fuel with local waste biomass in the village of Verkhni-Ozerski, Arkhangelsk Region, Russia. This village is evaluated as a pilot location representing the off-grid villages in the Russian Northern Territories. The U.S. Department of Energy (DOE) has agreed to provide technical assistance to the Ministry of Fuel and Energy (MFE). MFE has identified the Northern Territories as a priority area requiring NREL`s assistance. The program initially affects about 900 off-grid villages. Biomass and wind energy, and to a lesser extent small hydro (depending on resource availability) are expected to play the dominant role in the program, Geothermal energy may also have a role in the Russian Far East. The Arkhangelsk, Kariela, and Krasnoyarsk Regions, all in the Russian Northern Territories, have abundant forest resources and forest products industries, making them strong candidates for implementation of small-scale waste biomass-to-energy projects. The 900 or so villages included in the renewable energy program span nine administrative regions and autonomous republics. The regional authorities in the Northern Territories proposed these villages to MFE for consideration in the renewable energy program according to the following selection criteria: …
Date:
February 1, 1998
Creator:
Adamian, S.
Object Type:
Report
System:
The UNT Digital Library
Improved photon production data for MCNP{trademark}
Computer simulations with MCNP are often used to obtain information from measurements of neutron induced gamma-ray spectra. For such simulations to be useful, the complicated spectra produced by a wide variety of nuclides must be reproduced, requiring high quality nuclear data. A previous assessment of the neutron induced photon production data in the MCNP data libraries indicated a need for improvement. The photon production data were often based on outdated experiments and binned in such wide energy groups as to be of limited value for some applications. This paper describes the work that is underway at Los Alamos National Laboratory to improve the photon production data for thermal neutron capture reactions. To date, high quality photon production data for each stable isotope of chlorine, chromium, iron, copper, and nickel have been obtained. The improved spectra have been incorporated into ENDF formatted evaluations and processed into corresponding MCNP data files. Similar improvements for aluminum, manganese, silicon, calcium, and vanadium are also planned. The methodology used to produce the spectra is discussed, and sample results for chlorine are presented.
Date:
April 1, 1998
Creator:
Adams, A. A.; Frankle, S. C. & Little, R. C.
Object Type:
Article
System:
The UNT Digital Library
Feasibility Study of Dupoly to Recycle Depleted Uranium.
DUPoly, depleted uranium (DU) powder microencapsulated in a low-density polyethylene binder, has been demonstrated as an innovative and efficient recycle product, a very durable high density material with significant commercial appeal. DUPoly was successfully prepared using uranium tetrafluoride (UF{sub 4}) ''green salt'' obtained from Fluor Daniel-Fernald, a U.S. Department of Energy reprocessing facility near Cincinnati, Ohio. Samples containing up to 90 wt% UF{sub 4} were produced using a single screw plastics extruder, with sample densities of up to 3.97 {+-} 0.08 g/cm{sup 3} measured. Compressive strength of as-prepared samples (50-90 wt% UF4 ) ranged from 1682 {+-} 116 psi (11.6 {+-} 0.8 MPa) to 3145 {+-} 57 psi (21.7 {+-} 0.4 MPa). Water immersion testing for a period of 90 days produced no visible degradation of the samples. Leach rates were low, ranging from 0.02 % (2.74 x 10{sup {minus}6} gm/gm/d) for 50 wt% UF{sub 4} samples to 0.72 % (7.98 x 10{sup {minus}5} gm/gm/d) for 90 wt% samples. Sample strength was not compromised by water immersion. DUPoly samples containing uranium trioxide (UO{sub 3}), a DU reprocessing byproduct material stockpiled at the Savannah River Site, were gamma irradiated to 1 x 10{sup 9} rad with no visible deterioration. Compressive strength …
Date:
February 1, 1998
Creator:
Adams, J. W.; Lageraaen, P. R.; Kalb, P. D. & Rutenkroger, S. P.
Object Type:
Report
System:
The UNT Digital Library