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Lessons Learned from the NREL Village Power Program (open access)

Lessons Learned from the NREL Village Power Program

Renewable energy solutions for village power applications can be economical, functional, and sustainable. Pilot projects are an appropriate step in the development of a commercially viable market for rural renewable energy solutions. Moreover, there are a significant number of rural electrification projects under way that employ various technologies, delivery mechanisms, and financing arrangements. These projects, if properly evaluated, communicated, and their lessons incorporated in future projects and programs, can lead the way to a future that includes a robust opportunity for cost-effective, renewable-based village power systems. This paper summarizes some of NRELs recent experiences and lessons learned.
Date: July 1, 1998
Creator: Taylor, R.
System: The UNT Digital Library
Safety Aspects Related to the Radioactively Contaminated Forest Areas in Belarus. (open access)

Safety Aspects Related to the Radioactively Contaminated Forest Areas in Belarus.

None
Date: March 1, 1998
Creator: Sullivan, T.; Gibbs, B.; Andersson, K. G.; Roed, J.; Rymkevich, V. & Brekke, D.
System: The UNT Digital Library
Verification of Subsurface Barrier Integrity Using Perfluorocarbon Gas Tracers. (open access)

Verification of Subsurface Barrier Integrity Using Perfluorocarbon Gas Tracers.

None
Date: March 1, 1998
Creator: Sullivan, T. M.; Gibbs, B.; Senum, G.; Schwartz, M.; Hopkings, T. & Heiser, J.
System: The UNT Digital Library
Photochemical Solar Cells Based on Dye-Sensitization of Nanocrystalline TiO2 (open access)

Photochemical Solar Cells Based on Dye-Sensitization of Nanocrystalline TiO2

A photoelectrochemical solar cell that is based on the dye-sensitization of thin nanocrystalline films of TiO2 (anatase) nanoparticles in contact with a non-aqueous liquid electrolyte is described. The cell, fabricated at NREL, shows a conversion efficiency of -9.2% at AM1.5, which approaches the best reported value of 10%-11% by Grtzel at EPFL in Lausanne, Switzerland. The femtosecond (fs) pump-probe spectroscopy has been used to time resolve the injection of electrons into the conduction band of nanocrystalline TiO2 films under ambient conditions following photoexcitation of the adsorbed Ru(11)-complex dye. The measurement indicates an instrument-limited -50 fs upper limit on the electron injection time. We also report the sensitization of nanocrystalline TiO2 by a novel iron-based dye, CIS-[Fe 11 (2,2'-bipyridine-4,4'-dicarboxylic acid)2 (CN)2], a chromophore with an extremely short-lived, nonemissive excited state. The dye also exhibits a unique"band selective" sensitization through one of its two absorption bands. The operational principle of the device has been studied through the measurement of electric field distribution within the device structure and studies on the pH dependence of dye-redox potential. The incorporation of WO3 -based electrochromic layer into this device has led to a novel photoelectrochromic device structure for"smart window" application.
Date: July 1, 1998
Creator: Deb, S. K.; Ellingson, R.; Ferrere, S.; Frank, A. J.; Gregg, B. A.; Nozik, A. J. et al.
System: The UNT Digital Library
Lockheed Martin Hanford Corporation systems engineering project management (open access)

Lockheed Martin Hanford Corporation systems engineering project management

Lockheed Martin Hanford Corporation is developing and implementing an integrated technical baseline for cleaning up environmental contamination at the Hanford Site in Washington State. The Hanford Site is located in Washington State and has been referred to as one of the largest Environmental Cleanup challenges in the US. It became contaminated with radioactive and dangerous wastes during the 40+ years it was being used to produce weapons grade plutonium in support of the US nuclear weapons program (See Figure 1). The US Department of Energy (US DOE) is responsible for cleanup of the Hanford Site with the Environmental Protection Agency (EPA) and the Washington State Department of Ecology (Ecology) both providing regulatory oversight. The US DOE, EPA and Ecology entered into an agreement in 1989 (Hanford Federal Facility Agreement and Consent Order, commonly referred to as the Tri-Party Agreement) that provides the framework for cleanup of the Hanford Site. However, since the inception of the Tri-Party Agreement, there have been numerous changes due to technical issues, funding issues, and priority changes within the cleanup mission. As a result, progress on the definition and execution of the cleanup work has been slower than anticipated and has resulted in some false starts, …
Date: April 1, 1998
Creator: Baynes, P. A.
System: The UNT Digital Library
Proposed Forward Detectors for Diffractive Physics in CDF-II (open access)

Proposed Forward Detectors for Diffractive Physics in CDF-II

None
Date: April 1, 1998
Creator: Goulianos, K., Lami, S. & Collaborator, CDF
System: The UNT Digital Library
Operations Training Program (open access)

Operations Training Program

None
Date: January 1, 1998
Creator: Spata, Michael
System: The UNT Digital Library
Longitudinal and Transverse Cross Sections in the <sup>1</sup>H(e,e'K<sup>+</sup>)Lambda Reaction (open access)

Longitudinal and Transverse Cross Sections in the <sup>1</sup>H(e,e'K<sup>+</sup>)Lambda Reaction

The <sup>1</sup>H(e,e'K<sup>+</sup>)Lambda reaction was studied as a function of the squared four-momentum transfer, Q<sup>2</sup>, and the virtual photon polarizations. The Q<sup>2</sup> dependence of the sigma-L/sigma-T ratio differs significantly from current theoretical predictions. This, combined with the precision of the measurement, implies a need for revision of existing calculations.
Date: August 1, 1998
Creator: Niculescu, Gabriel; Gueye, Paul & Mtingwa, Sekazi
System: The UNT Digital Library
Structural Formation Studies of UV-Catalyzed Gels and Aerogels by Light Scattering (open access)

Structural Formation Studies of UV-Catalyzed Gels and Aerogels by Light Scattering

The skeletal structure of aerogel is determined before, during, and after the gel is formed. Supercritical drying of aerogel largely preserves the pore structure that is determined near the time of gelation. To better understand these gel formation mechanisms we carried out measurements of the time evolution of light scattering in a series of gels prepared without conventional acid or base catalysis. Instead, ultraviolet light was used to catalyze the formation of silica gels made from the hydrolysis of tetraethylorthosilicate and partly prehydrolyzed tetraethylorthosilicate in ethanol. Time evolution of light scattering provides information regarding the rate and geometrical nature of the assembly of the primary silica particles formed in the sol. UV-catalyzed gels show volumetric growth typical of acid-catalyzed gels, except when UV exposure is discontinued at the gel point, where gels then show linear chain formation typical of base-catalyzed gels. Long term UV exposure leads to coarsening of the pore network, a decrease in the clarity of the aerogel, and an increase in the surface area of the aerogel. Additionally, UV exposure up to the gel point leads to increased crystallinity in the final aerogel.
Date: April 1, 1998
Creator: Hunt, Arlon J. & Ayers, Michael R.
System: The UNT Digital Library
Development and testing of an information monitoring anddiagnostic system for large commercial buildings (open access)

Development and testing of an information monitoring anddiagnostic system for large commercial buildings

None
Date: August 1, 1998
Creator: Piette, Mary Ann; Gartland, Lisa; Khalsa, Satkartar; Rumsey,Peter; Lock, Lee Eng; Sebald, Anthony et al.
System: The UNT Digital Library
Designing an Epithermal Neutron Beam for Boron Neutron CaptureTherapy for the Fusion Reactions 2H(d,n)3He and 3H(d,n)4He (open access)

Designing an Epithermal Neutron Beam for Boron Neutron CaptureTherapy for the Fusion Reactions 2H(d,n)3He and 3H(d,n)4He

None
Date: August 1, 1998
Creator: Verbeke, J. M.; Costes, S. V.; Bleuel, D.; Vujic, J. & Leung, K. N.
System: The UNT Digital Library
A Sealed-Accelerator-Tube Neutron Generator for Boron Neutron Capture Therapy Application (open access)

A Sealed-Accelerator-Tube Neutron Generator for Boron Neutron Capture Therapy Application

Radio-frequency (RF) driven ion sources are being developed in Lawrence Berkeley National Laboratory (LBNL) for sealed-accelerator-tube neutron generator applications. By using a 2.5-cm-diameter RF-driven multicusp source and a computer designed 100 keV accelerator column, peak extractable hydrogen current exceeding 1 A from a 3-mm-diameter aperture, together with H{sup +} yields over 94% have been achieved. These experimental findings together with recent moderator design will enable one to develop compact 14 MeV neutron generators based on the D-T fusion reaction. In this new neutron generator, the ion source, the accelerator and the target are all housed in a sealed metal container without pumping. With a 120 keV and 1 A deuteron beam, it is estimated that a treatment time of {approx} 45 minutes is needed for boron neutron capture therapy.
Date: June 1, 1998
Creator: Leung, K. N.; Leung, K. N.; Lee, Y.; Verbeke, J. M.; Vurjic, J.; Williams, M. D. et al.
System: The UNT Digital Library
Investigation of 2H(d,n)3He and 3H(d,n)4He Fusion Reactions asAlternative Neutron Sources for BNCT (open access)

Investigation of 2H(d,n)3He and 3H(d,n)4He Fusion Reactions asAlternative Neutron Sources for BNCT

None
Date: June 1, 1998
Creator: Verbeke, J. M.; Vujic, J. & Leung, K. N.
System: The UNT Digital Library
Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers (open access)

Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers

Safety and reliability in glovebox operations can be significantly improved and waste packaging efficiencies can be increased by inserting flexible, lightweight, high capacity HEPA filters into the walls of plastic sheet barriers. This HEPA filter/barrier technology can be adapted to a wide variety of applications: disposable waste bags, protective environmental barriers for electronic equipment, single or multiple use glovebag assemblies, flexible glovebox wall elements, and room partitions. These reliable and inexpensive filtered barriers have many uses in fields such as radioactive waste processing, HVAC filter changeout, vapor or grit blasting, asbestos cleanup, pharmaceutical, medical, biological, and electronic equipment containment. The applications can result in significant cost savings, improved operational reliability and safety, and total waste volume reduction. This technology was developed at the Argonne National Laboratory-West (ANL-W) in 1993 and has been used at ANL-W since then at the TRU Waste Characterization Chamber Gloveboxes. Another 1998 AGS Conference paper titled "TRU Waste Characterization Gloveboxes", presented by Mr. David Duncan of ANL-W, describes these boxes.
Date: July 1, 1998
Creator: Pinson, Paul Arthur
System: The UNT Digital Library
Cross-industry Performance Modeling: Toward Cooperative Analysis (open access)

Cross-industry Performance Modeling: Toward Cooperative Analysis

One of the current unsolved problems in human factors is the difficulty in acquiring information from lessons learned and data collected among human performance analysts in different domains. There are several common concerns and generally accepted issues of importance for human factors, psychology and industry analysts of performance and safety. Among these are the need to incorporate lessons learned in design, to carefully consider implementation of new designs and automation, and the need to reduce human performance-based contributions to risk. In spite of shared concerns, there are several roadblocks to widespread sharing of data and lessons learned from operating experience and simulation, including the fact that very few publicly accessible data bases exist (Gertman & Blackman, 1994, and Kirwan, 1997). There is a need to draw together analysts and analytic methodologies to comprise a centralized source of data with sufficient detail to be meaningful while ensuring source anonymity. We propose that a generic source of performance data and a multi-domain data store may provide the first steps toward cooperative performance modeling and analysis across industries.
Date: October 1, 1998
Creator: Reece, Wendy Jane & Blackman, Harold Stabler
System: The UNT Digital Library
Destructive versus Nondestructive Assay Comparisons Using the SWEPP Gamma-ray Spectrometer (open access)

Destructive versus Nondestructive Assay Comparisons Using the SWEPP Gamma-ray Spectrometer

In support of data quality objectives for the INEEL Stored Waste Examination Pilot Plant (SWEPP) a series of 208-liter (55-gallon) waste drums containing inorganic sludge have been sampled and destructively analyzed. The drums were non-destructively assayed by the SWEPP PAN system and the SWEPP Gamma-Ray Spectrometer (SGRS) prior to sampling. This paper reports some of the conclusions from the destructive versus NDA comparisons, and additionally presents the results of an on-going effort to use the destructive analyses to validate absolute efficiency curves calculated using Monte-Carlo and analytical modeling for the SGRS. Destructive analysis results are available from radiochemical assay of 128 sludge-containing drums. The content codes represented are CC001 (42 items), CC002 (8), CC007 (48), CC800 (16), CC803 (3), and CC807 (11.) Each drum had two full-length vertical cores removed from designated radial positions. The entire length of each core was composited and submitted for analysis. All of the core composites were analyzed radiochemically for Am-241, Pu-239/240, and Pu-238, and by inductively-coupled mass spectrometry (ICPMS) for U-235 and U-238. Not only have the destructive analysis results been useful in documenting the performance of both the SGRS and the PAN system, but also have allowed the determination of certain absolute counting …
Date: November 1, 1998
Creator: Hartwell, John Kelvin; Harker, Yale Deon; Killian, Elmo Wayne & Yoon, Woo Yong
System: The UNT Digital Library
Imaging of Lamb Waves in Plates for Quantitative Determination of Anisotropy using Photorefractive Dynamic Holography (open access)

Imaging of Lamb Waves in Plates for Quantitative Determination of Anisotropy using Photorefractive Dynamic Holography

Anisotropic properties of sheet materials can be determined by measuring the propagation of Lamb waves in different directions. Electromagnetic acoustic transduction and laser ultrasonic methods provide noncontacting approaches that are often desired for application to industrial and processing environments. This paper describes a laser imaging approach utilizing the adaptive property of photorefractive materials to produce a real-time measurement of the antisymmetric Lamb wave mode in all directions simultaneously. Continuous excitation is employed enabling the data to be recorded and displayed by a CCD camera. Analysis of the image produces a direct quantitative determination of the phase velocity in all directions showing plate anisotropy in the plane. Many optical techniques for measuring ultrasonic motion at surfaces have been developed for use in applications such as vibration measurement and laser ultrasonics. Most of these methods have similar sensitivities and are based on time domain processing using homodyne, Fabry-Perot [1], and, more recently, photorefractive interferometry [2]. Generally, the methods described above do not allow measurement at more than one surface point simultaneously, requiring multiple beam movements and scanning in order to produce images of surface ultrasonic motion over a large area. Electronic speckle interferometry, including shearography, does provide images directly of vibrations over …
Date: June 1, 1998
Creator: Telschow, Kenneth Louis; Deason, Vance Albert; Schley, Robert Scott & Watson, Scott Marshall
System: The UNT Digital Library
Uncertainty Analysis of Nondestructive Assay Measurements of Nuclear Waste (open access)

Uncertainty Analysis of Nondestructive Assay Measurements of Nuclear Waste

Regulatory agencies governing the disposal of nuclear waste require that the waste be appropriately characterized prior to disposition. The most important aspect of the characterization process, establishing radionuclide content, is often achieved by nondestructive assay (NDA). For NDA systems to be approved for use in these applications, measurement uncertainty must be established. Standard “propagation of errors” methods provide a good starting point for considering the uncertainty analysis of NDA systems for nuclear waste. However, as compared with other applications (e.g., nuclear material accountability), using NDA systems for nuclear waste measurements presents some unique challenges. These challenges, stemming primarily from the diverse nature of the waste materials encountered, carry over into the uncertainty analysis as well. This paper reviews performance measures appropriate for the assessment of NDA uncertainty, describes characteristics of nuclear waste measurements that contribute to difficulties in assessing uncertainty, and outlines some statistics based methods for incorporating variability in waste characteristics in an uncertainty analysis.
Date: November 1, 1998
Creator: Blackwood, Larry Gene & Harker, Yale Deon
System: The UNT Digital Library
Using New Fission Data with the Multi-detector Analysis System for Spent Nuclear Fuel (open access)

Using New Fission Data with the Multi-detector Analysis System for Spent Nuclear Fuel

New experiments using an array of high purity germanium detectors and fast liquid scintillation detectors has been performed to observe the radiation emitted from the induced fission of 235U with a beam of thermal neutrons. The experiment was performed at the Argonne National Laboratory Intense Pulsed Neutron Source. Preliminary observations of the data are presented. A nondestructive analysis system for the characterization of DOE spent nuclear fuel based on these new data is presented.
Date: November 1, 1998
Creator: Cole, Jerald Donald
System: The UNT Digital Library
Estimating Production Potentials: Expert Bias in Applied Decision Making (open access)

Estimating Production Potentials: Expert Bias in Applied Decision Making

A study was conducted to evaluate how workers predict manufacturing production potentials given positively and negatively framed information. Findings indicate the existence of a bias toward positive information and suggest that this bias may be reduced with experience but is never the less maintained. Experts err in the same way non experts do in differentially processing negative and positive information. Additionally, both experts and non experts tend to overestimate production potentials in a positive direction. The authors propose that these biases should be addressed with further research including cross domain analyses and consideration in training, workplace design, and human performance modeling.
Date: October 1, 1998
Creator: Reece, Wendy Jane
System: The UNT Digital Library
Hygroscopic Fine Mode Particle Deposition on Electronic Circuitsand Resulting Degradation of Circuit Performance: An ExperimentalStudy (open access)

Hygroscopic Fine Mode Particle Deposition on Electronic Circuitsand Resulting Degradation of Circuit Performance: An ExperimentalStudy

A portion of electronic equipment failures is a consequenceof particle deposition on electronic circuits in normal indoorenvironments. Deposited hygroscopic particles reduce the electricalisolation (EI) between conductors. In laboratory experiments, weinvestigated the mechanisms, locations, and effects of particledeposition on electronic circuits with surface mounted chips (SMCs) andalso on small television sets. One set of electronics was exposed for 281h to an unusually high concentration of artificially-generated ammoniumsulfate particles while a second set (experimental controls) was exposedto normal indoor particles. The particle mass concentration in thehigh-exposure chamber was 500 times higher than normal. Televisionreliability was observed and the changes in EI between adjacent legs ofSMCs were measured. The experiments demonstrate the strong influence ofelectrostatic forces on the locations and rates of particle deposition.Although televisions did not fail after exposure to concentratedaerosols, the EI between adjacent legs of the SMCs was, in many cases,greatly diminished. Relative humidity had a very strong influence on themagnitude of EI. A qualitative explanation of the mechanisms of particledeposition and circuit degradation is proposed, including the role offibers. Finally, a potential method to reduce particle deposition onelectronic components is discussed.
Date: March 1, 1998
Creator: Litvak, Andres; Gadgil, A. & Fisk, W.J.
System: The UNT Digital Library
Evaluation of Natural Attenuation as One Component of Chloroethene-Contaminated Groundwater Remediation (open access)

Evaluation of Natural Attenuation as One Component of Chloroethene-Contaminated Groundwater Remediation

Test Area North (TAN) at the Idaho National Engineering and Environmental Laboratory (INEEL) is the site of a large trichloroethene (TCE) plume resulting from the historical injection of wastewater into the Snake River Plain Aquifer. The TAN Record of Decision (ROD) selected pump and treat as the final remedy and included a contingency for post-ROD treatability studies of alternative technologies. The technologies still under consideration are in situ bioremediation, in situ chemical oxidation, and natural attenuation. Both anaerobic and aerobic laboratory microcosm studies indicate the presence of microorganisms capable of chloroethene degradation. Field data indicate that TCE concentrations decrease relative to tritium and tetrachloroethene indicating an as yet unknown process is contributing to natural attenuation of TCE. Several methods for analyzing the field data have been evaluated and important limitations identified. Early results from the continued evaluation of the three alternative technologies suggest the combined approach of active remediation of the source area (in situ bioremediation and/or chemical oxidation replacing or augmenting pump and treat) and natural attenuation within the dissolved phase plume may be more cost and schedule effective than the base case pump and treat.
Date: October 1, 1998
Creator: Sorenson, K. S.; Peterson, L. N. & Green, T. S.
System: The UNT Digital Library
Generation of Subpicosecond X-ray Pulses Using RF OrbitDeflection (open access)

Generation of Subpicosecond X-ray Pulses Using RF OrbitDeflection

None
Date: July 1, 1998
Creator: Zholents, A.; Heimann, P.; Zolotorev, M. & Byrd, J.
System: The UNT Digital Library
Reducing Leaking Electricity to 1 Watt (open access)

Reducing Leaking Electricity to 1 Watt

In this study we examine some specific opportunities toreduce standby losses in electronic appliances. A review of powerconsumption levels for the major components responsible for standbyfunctions indicates that nearly all standby functions can be performedwith a total appliance standby power consumption of one watt or less. Wetherefore propose that standby losses be limited to one watt perappliance, a significant reduction from current levels for manyappliances. This target could be achieved with little or no extra cost tomanufacturers and could save over $2 billion in annual U.S. energy costs.Globally, a one-watt plan would lead to a significant reduction in carbonemissions.
Date: August 1, 1998
Creator: Meier, A. K.; Huber, Wolfgang & Rosen, Karen
System: The UNT Digital Library