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Environmental Report 2001

Description: The chapter summaries demonstrate the breadth of the environmental activities at LLNL. There are 14 chapters in this report: 3 chapters provide general information about the LLNL sites, regulatory activities, and the structure of environmental programs at LLNL; 10 chapters provide environmental monitoring measurements and analyses; and 1 chapter describes the quality assurance program and quality control activities that ensure the validity of the data. Brief descriptions of the contents of each of the individual chapters are presented here. Chapter 1, Introduction, describes the physical setting of the two LLNL sites. The description includes information about the topography, geology, and meteorology of the sites and clearly states the differences between them despite their proximity. Chapter 2, Compliance Summary, summarizes information about LLNL's substantial compliance activities, including compliance with the major federal, state, and local environmental initiatives. The major topics covered are the Clean Air Act, the Clean Water Act and related state programs, the Comprehensive Environmental Response, Compensation and Liability Act the Resource Conservation and Recovery Act and state and local hazardous waste regulations, the National Environmental Policy Act and the California Environmental Quality Act, the Endangered Species Act, the National Historic Preservation Act, and the Antiquities Act. Chapter 3, Environmental Program Information, describes the organization of LLNL's Environmental Protection Department and its divisions, giving the responsibilities of each organization for compliance and monitoring. Chapter 4, Air Effluent Monitoring, summarizes the facilities that have continuous air monitoring for their operations, including a summary of the results of the monitoring data collected for the sources. Chapter 5, Air Surveillance Monitoring, describes the purpose of the air particulate and tritium ambient air monitoring programs and provides analyses of the measurements taken in calendar year 2001. The chapter provides dose estimates from exposure to radiological materials in the ambient air. Chapter 6, Sewer ...
Date: September 1, 2002
Creator: Althouse, P E; Bertoldo, N A; Blake, R G; Brigdon, S L; Brown, R A; Campbell, C G et al.
Partner: UNT Libraries Government Documents Department

Modular intelligent sensor system

Description: This paper describes a sensor system architecture suitable for application in systems intended for battery powered unattended use. The modularity concept addresses the logical interconnects between modules, the electrical interconnects between modules, and a system for the generalization of data to permit modular processing.
Date: June 17, 1993
Creator: Fuess, D. A.
Partner: UNT Libraries Government Documents Department

Site Environmental Report summary, 1993

Description: This report describes the Fernald site mission, exposure pathways, and environmental standards and guidelines. Environmental monitoring activities measure and estimate the amount of radioactive and nonradioactive materials that may leave the site and enter the surrounding environment. This presents an overall view of the impact these activities have on the local environment and public health.
Date: June 1, 1994
Partner: UNT Libraries Government Documents Department

Two-dimensional numerical simulation of a Stirling engine heat exchanger

Description: This paper describes the first phase of an effort to develop multidimensional models of Stirling engine components; the ultimate goal is to model an entire engine working space. More specifically, this paper describes parallel plate and tubular heat exchanger models with emphasis on the central part of the channel (i.e., ignoring hydrodynamic and thermal end effects). The model assumes: Laminar, incompressible flow with constant thermophysical properties. In addition, a constant axial temperature gradient is imposed. The governing equations, describing the model, have been solved Crack-Nicloson finite-difference scheme. Model predictions have been compared with analytical solutions for oscillating/reversing flow and heat transfer in order to check numerical accuracy. The simplifying assumptions will later be relaxed to permit modeling of incompressible, laminar/turbulent flow that occurs in Stirling heat exchanger. Excellent agreement has been obtained for the model predictions with analytical solutions available for both flow in circular tubes and between parallel plates. Also the heat transfer computational results are in good agreement with the heat transfer analytical results for parallel plates.
Date: September 1, 1994
Creator: Ibrahim, M. B.; Tew, R. C. & Dudenhoefer, J. E.
Partner: UNT Libraries Government Documents Department

Advanced gas turbine systems research. Quarterly technical progress report, April 1, 1994--June 30, 1994

Description: A cooperative development of gas turbines for electric power generation in USA is underway. Since the first AGTSR program manager has retired, a search for a new manager has begun. Reports during this period include membership, combustion instability white paper, and a summary paper for the ASME IGTI conference.
Date: July 1, 1994
Partner: UNT Libraries Government Documents Department

Heterogeneous catalytic process for alcohol fuels from syngas. Fifth quarterly technical progress report, January--March, 1993

Description: Objective is to evaluate heterogeneous catalysts for converting syngas to oxygenates for use as fuel enhancers, and to develop the best total process for converting syngas to liquid fuels. Two tasks are being pursued: Catalyst R and D, and engineering studies. Initial work will be on the isobutanol catalyst system. A microreactor has been prepared for screening heterogeneous catalysts.
Date: November 1, 1993
Partner: UNT Libraries Government Documents Department

Design/Installation and Structural Integrity Assessment of Bethel Valley Low-Level Waste collection and transfer system upgrade for Building 3092 (central off-gas scrubber facility) at Oak Ridge National Laboratory

Description: This document describes and assesses planned modifications to be made to the Building 3092 Central Off-Gas Scrubber Facility of the Oak Ridge National Laboratory, Oak Ridge, Tennessee. The modifications are made in response to the requirements of 40CFR264 Subpart J, relating to environmental protection requirements for buried tank systems. The modifications include the provision of a new scrubber recirculation tank in a new, below ground, lined concrete vault, replacing an existing recirculation sump that does not provide double containment. A new buried, double contained pipeline is provided to permit discharge of spent scrubber recirculation fluid to the Central Waste Collection Header. The new vault, tank, and discharge line are provided with leak detection and provisions to remove accumulated liquid. Ne scrubber recirculation pumps, piping, and accessories are also provided. This assessment concludes that the planned modifications comply with applicable requirements of 40CFR264 Subpart J, as set forth in Appendix F to the Federal Facility Agreement, Docket No. 89-04-FF, covering the Oak Ridge Reservation. A formal design certification statement is included herein on Page 53, a certification covering the installation shall be executed prior to placing the modified facility into service.
Date: October 1, 1994
Partner: UNT Libraries Government Documents Department

ATOMISTIC SIMULATION OF VACANCY AND SELF-INTERSTITIAL DIFFUSION IN Fe-Cu ALLOYS

Description: Neutron hardening and embrittlement of pressure vessel steels is due to a high density of nanometer scale features, including Cu-rich precipitates which form as a result of radiation enhanced diffusion. High-energy displacement cascades generate large numbers of both isolated point defects and clusters of vacancies and interstitials. The subsequent clustering, diffusion and ultimate annihilation of primary damage is inherently coupled with solute transport and hence, the overall chemical and microstructural evolutions under irradiation. In this work, we present atomistic simulation results, based on many-body interatomic potentials, of the migration of vacancies, solute and self-interstitial atoms (SIA) in pure Fe and binary Fe-0.9 and 1.0 at.% Cu alloys. Cu diffusion occurs by a vacancy mechanism and the calculated Cu diffusivity is in good agreement with experimental data. Strain field interactions between the oversized substitutional Cu solute atoms and SIA and SIA clusters are predominantly repulsive and result in both a decreased activation energy and diffusion pre-factor for SIA and small (N < 5) SIA cluster migration, which occurs by three-dimensional motion. The Cu appears to enhance the reorientation of the SIA clusters to different <111> directions, as well as the transition from <110> to mobile <111> configurations. The migration behavior of larger SIA clusters, which undergo only one-dimensional diffusion during molecular dynamics timescales, is largely unaffected by the Fe-Cu alloy, although SIA clusters are effectively repelled by coherent Cu precipitates.
Date: January 25, 2001
Creator: Marian, J; Wirth, B D; Perlado, J M; Odette, G R & Diaz de la Rubia, T
Partner: UNT Libraries Government Documents Department

OCRWM procedure for reporting software baseline change information

Description: The purpose of this procedure is to establish a requirement and method for participant organizations to report software baseline change information to the M&O Configuration Management (CM) organization for inclusion in the OCRWM Configuration Information System (CIS). (The requirements for performing software configuration management (SCM) are found in the OCRWM Quality Assurance Requirements and Description (QARD) document and in applicable DOE orders, and not in this procedure.) This procedure provides a linkage between each participant`s SCM system and the CIS, which may be accessed for identification, descriptive, and contact information pertaining to software released by a participant. Such information from the CIS will enable retrieval of details and copies of software code and documentation from the participant SCM system.
Date: July 1, 1994
Partner: UNT Libraries Government Documents Department

Electron density profile from visible bremsstrahlung array measurements on TFTR

Description: A new asymmetric Abel inversion method developed for interferometry is applied to tangential visible bremsstrahlung (VB) array (16 channels) measurements on TFTR to evaluate electron density and Z{sub eff} profiles. the electron density profile deduced from VB array measurements is meaningful in tokamak plasmas where the Z{sub eff} profile is flat or nearly flat. In addition, a preliminary result shows that the Z{sub eff} profile is hollow in high power neutral-beam heated plasmas.
Date: October 1, 1993
Creator: Park, H. K. & Adler, H.
Partner: UNT Libraries Government Documents Department

Microscopic evaluation of low-temperature embrittlement in Type 308 stainless steel welds

Description: Effect of aging of type 308 stainless steel weld metal from 400 to 550C on microstructure was examined. Microstructural development was correlated with earlier results on mechanical properties that showed the ferrite-containing welds were prone to severe embrittlement when aged in this temperature range. The embrittlement was manifested by an increase in the ductile-brittle transition temperature and a drop in the upper-shelf energy. It was found that although the embrittlement over this aging temperature range was comparable, the microstructural changes that were responsible for the embrittlement were different at different temperatures. Embrittlement was caused by a combination of spinodal decomposition of ferrite, precipitation of M{sub 23}C{sub 6} carbide at the ferrite/austenite interface, and G-phase precipitation within the ferrite. Sigma phase formation at 550C may also be a contributing factor to the embrittlement.
Date: September 1, 1993
Creator: Vitek, J. M.; David, S. A. & Alexander, D. J.
Partner: UNT Libraries Government Documents Department

BioZoom: Exploiting Source-Capability Information for Integrated Access to Multiple Bioinformatics Data Sources

Description: Modern Bioinformatics data sources are widely used by molecular biologists for homology searching and new drug discovery. User-friendly and yet responsive access is one of the most desirable properties for integrated access to the rapidly growing, heterogeneous, and distributed collection of data sources. The increasing volume and diversity of digital information related to bioinformatics (such as genomes, protein sequences, protein structures, etc.) have led to a growing problem that conventional data management systems do not have, namely finding which information sources out of many candidate choices are the most relevant and most accessible to answer a given user query. We refer to this problem as the query routing problem. In this paper we introduce the notation and issues of query routing, and present a practical solution for designing a scalable query routing system based on multi-level progressive pruning strategies. The key idea is to create and maintain source-capability profiles independently, and to provide algorithms that can dynamically discover relevant information sources for a given query through the smart use of source profiles. Compared to the keyword-based indexing techniques adopted in most of the search engines and software, our approach offers fine-granularity of interest matching, thus it is more powerful and effective for handling queries with complex conditions.
Date: January 9, 2003
Creator: Liu, L; Buttler, D; Critchlow, T J; Han, W; Paques, H; Pu, C et al.
Partner: UNT Libraries Government Documents Department

Structural Modifications in Fused Silica Due to Laser Damage Induced Shock Compression

Description: High power laser pulses can produce damage in high quality fused silica optics that can lead to its eventual obscuration and failure. Current models suggest the initiation of a plasma detonation due to absorbing initiators and defects, leading to the formation of shock waves. Recent experiments have found a densified layer at the bottom of damage sites, as evidence of the laser-damage model. We have studied the propagation of shock waves through fused silica using molecular dynamics. These simulations show drastic modifications in the structure and topology of the network, in agreement with experimental observations.
Date: December 5, 2001
Creator: Kubota, A; Davila, L; Caturla, M J; Stolken, J S; Sadigh, B; Quong, A et al.
Partner: UNT Libraries Government Documents Department

Designing an enhanced groundwater sample collection system

Description: As part of an ongoing technical support mission to achieve excellence and efficiency in environmental restoration activities at the Laboratory for Energy and Health-Related Research (LEHR), Pacific Northwest Laboratory (PNL) provided guidance on the design and construction of monitoring wells and identified the most suitable type of groundwater sampling pump and accessories for monitoring wells. The goal was to utilize a monitoring well design that would allow for hydrologic testing and reduce turbidity to minimize the impact of sampling. The sampling results of the newly designed monitoring wells were clearly superior to those of the previously installed monitoring wells. The new wells exhibited reduced turbidity, in addition to improved access for instrumentation and hydrologic testing. The variable frequency submersible pump was selected as the best choice for obtaining groundwater samples. The literature references are listed at the end of this report. Despite some initial difficulties, the actual performance of the variable frequency, submersible pump and its accessories was effective in reducing sampling time and labor costs, and its ease of use was preferred over the previously used bladder pumps. The surface seals system, called the Dedicator, proved to be useful accessory to prevent surface contamination while providing easy access for water-level measurements and for connecting the pump. Cost savings resulted from the use of the pre-production pumps (beta units) donated by the manufacturer for the demonstration. However, larger savings resulted from shortened field time due to the ease in using the submersible pumps and the surface seal access system. Proper deployment of the monitoring wells also resulted in cost savings and ensured representative samples.
Date: October 1, 1994
Creator: Schalla, R.
Partner: UNT Libraries Government Documents Department