States

Characterization of Russian ballistic furnace shells, February, 1999, batch (open access)

Characterization of Russian ballistic furnace shells, February, 1999, batch

This report documents the characterization of the latest batch of shells produced in the Ballistic Furnace System at the Lebedev Physical Institute, Moscow, Russia, that we received in mid-February, 1999. The batch consisted of three cassettes containing 36 shells in each cassette. An initial sphericity measurement was done, each shell was weighed, and shells were selected that were spherical enough to run on the Sphere Mapper AFM.
Date: April 2, 1999
Creator: Fearon, E
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada (open access)

Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada

This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, …
Date: April 2, 1999
Creator: United States. Department of Energy. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada Appendix D - Corrective Action Investigation Report, Central Nevada Test Area, CAU 417 (open access)

Corrective Action Decision Document for Corrective Action Unit 417: Central Nevada Test Area Surface, Nevada Appendix D - Corrective Action Investigation Report, Central Nevada Test Area, CAU 417

This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 417: Central Nevada Test Area Surface, Nevada, under the Federal Facility Agreement and Consent Order. Located in Hot Creek Valley in Nye County, Nevada, and consisting of three separate land withdrawal areas (UC-1, UC-3, and UC-4), CAU 417 is comprised of 34 corrective action sites (CASs) including 2 underground storage tanks, 5 septic systems, 8 shaker pad/cuttings disposal areas, 1 decontamination facility pit, 1 burn area, 1 scrap/trash dump, 1 outlier area, 8 housekeeping sites, and 16 mud pits. Four field events were conducted between September 1996 and June 1998 to complete a corrective action investigation indicating that the only contaminant of concern was total petroleum hydrocarbon (TPH) which was found in 18 of the CASs. A total of 1,028 samples were analyzed. During this investigation, a statistical approach was used to determine which depth intervals or layers inside individual mud pits and shaker pad areas were above the State action levels for the TPH. Other related field sampling activities (i.e., expedited site characterization methods, …
Date: April 2, 1999
Creator: United States. Department of Energy.
Object Type: Report
System: The UNT Digital Library
Distribution of Components in Ion Exchange Materials Taken from the K East Basin and Leaching of Ion Exchange Materials by Nitric/Hydrofluoric Acid and Nitric/Oxalic Acid (open access)

Distribution of Components in Ion Exchange Materials Taken from the K East Basin and Leaching of Ion Exchange Materials by Nitric/Hydrofluoric Acid and Nitric/Oxalic Acid

Laboratory tests were performed to examine the efficacy of mixed nitric/hydrofluoric acid followed by mixed nitric/oxalic acid leach treatments to decontaminate ion exchange materials that have been found in a number of samples retrieved from K East (KE)Basin sludge. The ion exchange materials contain organic ion exchange resins and zeolite inorganic ion exchange material. Based on process records, the ion exchange resins found in the K Basins is a mixed-bed, strong acid/strong base material marketed as Purolite NRW-037. The zeolite material is Zeolon-900, a granular material composed of the mineral mordenite. Radionuclides sorbed or associated with the ion exchange material can restrict its disposal to the Environmental Restoration Disposal Facility (ERDF). The need for testing to support development of a treatment process for K Basin sludge has been described in Section 4.2 of ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process'' (Flament 1998). Elutriation and washing steps are designed to remove the organic resins from the K Basin sludge. To help understand the effects of the anticipated separation steps, tests were performed with well-rinsed ion exchange (IX) material from KE Basin floor sludge (sample H-08 BEAD G) and with well-rinsed IX having small quantities of added …
Date: April 2, 1999
Creator: Delegard, C. H.; Rinehart, D. E. & Hoopes, F. V.
Object Type: Report
System: The UNT Digital Library
Facility Effluent Monitoring Plan for Pacific Northwest National Laboratory Balance-of-Plant Facilities (open access)

Facility Effluent Monitoring Plan for Pacific Northwest National Laboratory Balance-of-Plant Facilities

The Pacific Northwest National Laboratory (PNNL) operates a number of research and development (R and D) facilities for the Department of Energy on the Hanford Site. According to DOE Order 5400.1, a Facility Effluent Monitoring Plan is required for each site, facility, or process that uses, generates, releases, or manages significant pollutants or hazardous materials. Three of the R and D facilities: the 325, 331, and 3720 Buildings, are considered major emission points for radionuclide air sampling and thus individual Facility Effluent Monitoring Plans (FEMPs) have been developed for them. Because no definition of ''significant'' is provided in DOE Order 5400.1 or the accompanying regulatory guide DOE/EH-0173T, this FEMP was developed to describe monitoring requirements in the DOE-owned, PNNL-operated facilities that do not have individual FEMPs. The remainder of the DOE-owned, PNNL-operated facilities are referred to as Balance-of-Plant (BOP) facilities. Activities in the BOP facilities range from administrative to laboratory and pilot-scale R and D. R and D activities include both radioactive and chemical waste characterization, fluid dynamics research, mechanical property testing, dosimetry research, and molecular sciences. The mission and activities for individual buildings are described in the FEMP.
Date: April 2, 1999
Creator: Ballinger, M.Y. & Shields, K.D.
Object Type: Report
System: The UNT Digital Library
Facility Effluent Monitoring Plan for the 325 Radiochemical Processing Laboratory (open access)

Facility Effluent Monitoring Plan for the 325 Radiochemical Processing Laboratory

This Facility Effluent Monitoring Plan (FEMP) has been prepared for the 325 Building Radiochemical Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) to meet the requirements in DOE Order 5400.1, ''General Environmental Protection Programs.'' This FEMP has been prepared for the RPL primarily because it has a ''major'' (potential to emit >0.1 mrem/yr) emission point for radionuclide air emissions according to the annual National Emission Standards for Hazardous Air Pollutants (NESHAP) assessment performed. This section summarizes the airborne and liquid effluents and the inventory based NESHAP assessment for the facility. The complete monitoring plan includes characterization of effluent streams, monitoring/sampling design criteria, a description of the monitoring systems and sample analysis, and quality assurance requirements. The RPL at PNNL houses radiochemistry research, radioanalytical service, radiochemical process development, and hazardous and radioactive mixed waste treatment activities. The laboratories and specialized facilities enable work ranging from that with nonradioactive materials to work with picogram to kilogram quantities of fissionable materials and up to megacurie quantities of other radionuclides. The special facilities within the building include two shielded hot-cell areas that provide for process development or analytical chemistry work with highly radioactive materials and a waste treatment facility for processing hazardous, …
Date: April 2, 1999
Creator: Shields, K.D. & Ballinger, M.Y.
Object Type: Report
System: The UNT Digital Library
Facility Effluent Monitoring Plan for the 331 Complex (open access)

Facility Effluent Monitoring Plan for the 331 Complex

None
Date: April 2, 1999
Creator: Ballinger, M.Y. & Shields, K.D.
Object Type: Report
System: The UNT Digital Library
Facility Effluent Monitoring Plan for the 3720 Building (open access)

Facility Effluent Monitoring Plan for the 3720 Building

This Facility Effluent Monitoring Plan (FEMP) has been prepared for the Environmental Science Laboratory (3720 Facility) at the Pacific Northwest National Laboratory (PNNL) to meet the requirements in DOE Order 5400.1, ''General Environmental Protection Programs'' This FEMP has been prepared for the 3720 Facility primarily because it has a major (potential to emit >0.1 mrem/yr) emission point for radionuclide air emissions according to the annual National Emission Standards for Hazardous Air Pollutants (NESHAP) assessment performed. This section summarizes the airborne and liquid effluents and the inventory based NESHAP assessment for the facility. The complete monitoring plan includes characterization of effluent streams, monitoring/sampling design criteria, a description of the monitoring systems and sample analysis, and quality assurance requirements. The 3720 Facility provides office and laboratory space for PNNL scientific and engineering staff conducting multidisciplinary research in the areas of materials characterization and testing and waste management. The facility is designed to accommodate the use of radioactive and hazardous materials to conduct these activities. Radioactive material storage and usage occur throughout the facility and include a large number of isotopes. This material is in several forms, including solid, liquid, and dispersible particulate. The facility is in the process of being vacated for …
Date: April 2, 1999
Creator: Shields, K.D. & Ballinger, M.Y.
Object Type: Report
System: The UNT Digital Library
Fire-Induced Response in Foam Encapsulants (open access)

Fire-Induced Response in Foam Encapsulants

The paper provides a concise overview of a coordinated experimental/theoretical/numerical program at Sandia National Laboratories to develop an experimentally validated model of fire-induced response of foam-filled engineered systems for nuclear and transportation safety applications. Integral experiments are performed to investigate the thermal response of polyurethane foam-filled systems exposed to fire-like heat fluxes. A suite of laboratory experiments is performed to characterize the decomposition chemistry of polyurethane. Mass loss and energy associated with foam decomposition and chemical structures of the virgin and decomposed foam are determined. Decomposition chemistry is modeled as the degradation of macromolecular structures by bond breaking followed by vaporization of small fragments of the macromolecule with high vapor pressures. The chemical decomposition model is validated against the laboratory data. Data from integral experiments is used to assess and validate a FEM foam thermal response model with the chemistry model developed from the decomposition experiments. Good agreement was achieved both in the progression of the decomposition front and the in-depth thermal response.
Date: April 2, 1999
Creator: Borek, T. T.; Chu, T. Y.; Erickson, K. L.; Gill, W.; Hobbs, M. L.; Humphries, L. L. et al.
Object Type: Article
System: The UNT Digital Library
Future Role of the Cost Accounting Standards Board (open access)

Future Role of the Cost Accounting Standards Board

Other written product issued by the General Accounting Office with an abstract that begins "GAO published a summary of recommendations made by the Cost Accounting Standards (CAS) Board Review Panel regarding the CAS Board and the CAS system. The panel believes that reforms are needed to encourage the participation of new commercial companies in government procurement and to reduce the burden of government unique accounting requirements on smaller companies. The panel believes that: (1) there should be changes to CAS' location, membership, and staffing; (2) there should be changes in CAS applicability thresholds; (3) Congress should provide contracting agencies with responsibility for contract administration related to CAS; and (4) an overall review of the CAS and its attendant requirements is warranted to judge whether the standards should be streamlined."
Date: April 2, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Griffith Energy Project Final Environmental Impact Statement (open access)

Griffith Energy Project Final Environmental Impact Statement

Griffith Energy Limited Liability Corporation (Griffith) proposes to construct and operate the Griffith Energy Project (Project), a natural gas-fuel, combined cycle power plant, on private lands south of Kingman, Ariz. The Project would be a ''merchant plant'' which means that it is not owned by a utility and there is currently no long-term commitment or obligation by any utility to purchase the capacity and energy generated by the power plant. Griffith applied to interconnect its proposed power plant with the Western Area Power Administration's (Western) Pacific Northwest-Pacific Southwest Intertie and Parker-Davis transmission systems. Western, as a major transmission system owner, needs to provide access to its transmission system when it is requested by an eligible organization per existing policies, regulations and laws. The proposed interconnection would integrate the power generated by the Project into the regional transmission grid and would allow Griffith to supply its power to the competitive electric wholesale market. Based on the application, Western's proposed action is to enter into an interconnection and construction agreement with Griffith for the requested interconnections. The proposed action includes the power plant, water wells and transmission line, natural gas pipelines, new electrical transmission lines and a substation, upgrade of an existing …
Date: April 2, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Illegal Aliens: Significant Obstacles to Reducing Unauthorized Alien Employment Exist (open access)

Illegal Aliens: Significant Obstacles to Reducing Unauthorized Alien Employment Exist

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Attorney General's strategy for enforcing workplace immigration laws, focusing on: (1) the effectiveness of the employment verification process in preventing employers from hiring unauthorized aliens; (2) the Immigration and Naturalization Service's (INS) efforts to improve the employment verification process; (3) the level of effort INS and the Department of Labor (DOL) devoted to worksite enforcement activities and the results of these activities; and (4) changes being made to INS' worksite enforcement program."
Date: April 2, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
K Basin Sludge Conditioning Process Testing Project Results from Test 4, ''Acid Digestion of Mixed-Bed Ion Exchange Resin'' (open access)

K Basin Sludge Conditioning Process Testing Project Results from Test 4, ''Acid Digestion of Mixed-Bed Ion Exchange Resin''

Approximately 73 m{sup 3} of heterogeneous solid material, ''sludge,'' (upper bound estimate, Packer 1997) have accumulated at the bottom of the K Basins in the 100 K Area of the Hanford Site. This sludge is a mixture of spent fuel element corrosion products, ion exchange materials (organic and inorganic), graphite-based gasket materials, iron and aluminum metal corrosion products, sand, and debris (Makenas et al. 1996, 1997). In addition, small amounts of polychlorinated biphenyls (PCBs) have been found. Ultimately, it is planned to transfer the K Basins sludge to the Hanford double shell tanks (DSTs). The Hanford Spent Nuclear Fuel (HSNF) project has conducted a number of evaluations to examine technology and processing alternatives to pretreat K Basin sludge to meet storage and disposal requirements. From these evaluations, chemical pretreatment has been selected to address criticality issues, reactivity, and the destruction or removal of PCBs before the K Basin sludge can be transferred to the DSTs. Chemical pretreatment, referred to as the K Basin sludge conditioning process, includes nitric acid dissolution of the sludge (with removal of acid insoluble solids), neutrons absorber addition, neutralization, and reprecipitation. Laboratory testing is being conducted by the Pacific Northwest National Laboratory (PNNL) to provide data …
Date: April 2, 1999
Creator: Pool, K. H.; Delegard, C. H.; Schmidt, A. J.; Thornton, B. M. & Silvers, K. L.
Object Type: Report
System: The UNT Digital Library
K Basin Sludge Conditioning Testing Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing (open access)

K Basin Sludge Conditioning Testing Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing

This report describes work performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) to support the development of the K Basin Sludge Treatment System. For this work, testing was performed to examine the dissolution behavior of a K East Basin floor and Weasel Pit sludge composite, referred to as K East area sludge composite, in nitric acid at the following concentrations: 2 M, 4 M, 6 M and 7.8 M. With the exception of one high solids loading test the nitric acid was added at 4X the stoichiometric requirement (assuming 100% of the sludge was uranium metal). The dissolution tests were conducted at boiling temperatures for 24 hours. Most of the tests were conducted with {approximately}2.5 g of sludge (dry basis). The high solids loading test was conducted with {approximately}7 g of sludge. A large-scale dissolution test was conducted with 26.5 g of sludge and 620 mL of 6 M nitric acid. The objectives of this test were to (1) generate a sufficient quantity of acid-insoluble residual solids for use in leaching studies, and (2) examine the dissolution behavior of the sludge composite at a larger scale.
Date: April 2, 1999
Creator: Carlson, C. D.; Delegard, C. H.; Burgeson, I. E.; Schmidt, A. J. & Silvers, K. L.
Object Type: Report
System: The UNT Digital Library
Material Requirements for Buffer Layers Used to Obtain Solar Cells with High Open Circuit Voltages (open access)

Material Requirements for Buffer Layers Used to Obtain Solar Cells with High Open Circuit Voltages

This paper discusses material requirements for junction layers needed to obtain solar cells with highest possible open-circuit voltages (VOC). In a typical a-Si:H-based ''p/i/n'' solar cell, this includes the transparent conductive oxide (TCO) contact layer, the p-layer, a ''buffer layer'' inserted at the p/i interface, and the surface portion of the intrinsic layer. In HIT-cells, the i-layer between (n-type) c-Si and (p-type) a-Si:H may be regarded as the buffer. Our suggestion to obtain high values of VOC relies on using materials with high lifetimes and low carrier mobilities that are capable of reducing surface or junction recombination by reducing the flow of carriers into this loss-pathway. We provide a general calculation that supports these approaches and can explain why these schemes are beneficial for all solar cells.
Date: April 2, 1999
Creator: von Roedern, B. & Bauer, G. H.
Object Type: Article
System: The UNT Digital Library
Radionuclide Leaching from Organic Ion Exchange Resin (open access)

Radionuclide Leaching from Organic Ion Exchange Resin

Laboratory tests were performed to examine the efficacy of leach treatments for decontaminating organic ion exchange resins (OIER), which have been found in a number of samples retrieved from K East Basin sludge. Based on process records, the OIER found in the K Basins is a mixed-bet strong acid/strong base material marketed as Purolite{trademark} NRW-037. Radionuclides sorbed or associated with the OIER can restrict its disposal to the Environmental Restoration Disposal Facility (ERDF). The need for testing to support development of a treatment process for K Basin sludge has been described in Section 4.2 of ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process'' (Flament 1998). To help understand the effects of anticipated OIER elutriation and washing, tests were performed with well-rinsed OIER material from K East Basin floor sludge (sample H-08 BEAD G) and with well-rinsed OIER having approximately 5% added K East canister composite sludge (sample KECOMP). The rinsed resin-bearing material also contained the inorganic ion exchanger Zeolon-900{trademark}, a zeolite primarily composed of the mineral mordenite. The zeolite was estimated to comprise 27 weight percent of the dry H-08 BEAD G material.
Date: April 2, 1999
Creator: Delegard, C. H. & Rinehart, D. E.
Object Type: Report
System: The UNT Digital Library
Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of Composite K East Canister Sludge (open access)

Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of Composite K East Canister Sludge

Laboratory tests were performed to examine mixed nitric/hydrofluoric acid leach treatments for decontaminating dissolver residual solids (KECDVSR24H-2) produced during a 20- to 24-hr dissolution of a composite K East (KE) Basin canister sludge in 95 C 6 M nitric acid (HNO{sub 3}). The scope of this testing has been described in Section 4.5 of ''Testing Strategy to Support the Development of K Basin Sludge Treatment Process'' (Flament 1998). Radionuclides sorbed or associated with the residual solids generated in the K Basin sludge treatment process can restrict disposal of this solid to the Environmental Restoration Disposal Facility (ERDF). The starting dissolver residual solid for this testing, KECDVSR24H-2, contains radionuclides at concentrations which exceed the ERDF Waste Acceptance Criteria for TRU by about a factor of 70, for {sup 239}Pu by a factor of 200, and for {sup 241}Am by a factor of 50. The solids also exceed the ERDF criterion for {sup 137}Cs by a factor of 2 and uranium by a factor of 5. Therefore, the radionuclides of greatest interest in this leaching study are first {sup 239}Pu and {sup 241}Am (both components of TRU) and then uranium and {sup 137}Cs.
Date: April 2, 1999
Creator: Delegard, C. H.; Rinehart, D. E.; Soderquist, C. Z. & Fadeff, S. K.
Object Type: Report
System: The UNT Digital Library
Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of K East Area Sludge Composite (open access)

Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of K East Area Sludge Composite

Laboratory tests were performed to examine the efficacy of various leach treatments for decontaminating dissolver residual solids (KEACRESID1) produced during a 24-hour dissolution of K East Basin floor and Weasel Pit sludge composite in boiling 6 M HNO{sub 3}. The scope of this testing has been described in Section 4.5 of ''Testing Strategy to Support the Development of K Basin Sludge Treatment Process'' (Flament 1998). Radionuclides sorbed or associated with the residual solids generated in the K Basin sludge treatment process can restrict disposal of this solid to the Environmental Restoration Disposal Facility (ERDF). The starting dissolver residual solid for this testing, KEACRESID1, is a visibly heterogeneous material. This material contains radionuclides at concentrations above the ERDF Waste Acceptance Criteria for transuranics (TRU) by about a factor of 3, for {sup 239}Pu by a factor of 10, and for {sup 241}Am by a factor of 1.6. It meets the ERDF criterion for {sup 137}Cs by a factor of 4 and for uranium by a factor of 10. Therefore, the radionuclides of greatest interest in this leaching study are first {sup 239}Pu, and then {sup 241}Am, {sup 137}Cs, and uranium.
Date: April 2, 1999
Creator: Delegard, C. H.; Rinehart, D. E.; Carlson, C. D.; Soderquist, C. Z. & Fadeff, S. K.
Object Type: Report
System: The UNT Digital Library
Reduction of Risk in Exploration and Prospect Generation through a Multidisciplinary Basin-Analysis Program in the South-Central Mid-Continent Region (open access)

Reduction of Risk in Exploration and Prospect Generation through a Multidisciplinary Basin-Analysis Program in the South-Central Mid-Continent Region

This report will discuss a series of regional studies that were undertaken within the South-Central Mid-Continent region of the U.S. Coverage is also provided about a series of innovative techniques that were used for this assessment.
Date: April 2, 1999
Creator: Reeves, T. K.; Banerjee, Sanjay; Jordan, John; Szpakiewicz, Michael; Safley, Eugene; Guo, Genliang et al.
Object Type: Report
System: The UNT Digital Library
Regulatory Flexibility Act: Agencies' Interpretations of Review Requirements Vary (open access)

Regulatory Flexibility Act: Agencies' Interpretations of Review Requirements Vary

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO updated its previous reports on agencies' use of the Unified Agenda of Federal Regulatory and Deregulatory Actions to publish final rule notices, focusing on: (1) how many agencies had no Agenda entries that were characterized as Regulatory Flexibility Act (RFA) of 1980, section 610 reviews, whether agencies are interpreting the review requirements consistently, and why certain agencies that appeared subject to the requirements had no entries; (2) how many of the section 610 review entries in these Agendas appeared to meet the notification requirements in subsection 610(c); (3) if the section 610 review entries did not appear to meet the statutory requirements, why certain agencies' entries were characterized as section 610 reviews; and (4) whether any federal agencies had revised their section 610 review plans."
Date: April 2, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Short-pulse laser materials processing (open access)

Short-pulse laser materials processing

The goal of this project was to develop, through experiments and modeling, a better understanding of the physics issues and machining techniques related to short-pulse laser materials processing. Although we have successfully demonstrated many types of cuts in a wide range of materials, our general short-pulse machiing scientific knowledge and our ability to model the complex physical processes involved are limited. During this past year we made good progress in addressing some of these issues, but there remain many unanswered questions. Section 2 begins with a theoretical look at short-pulse laser ablation of material using a 1-D radiation-hydrodynamic code which includes a self-consistent description of laser absorption and reflection from an expanding plasma. In Section 3 we present measurements of scaling relationships, hole drilling progression, electric field and polarization effects, and a detailed look at the interesting structures formed during hole drilling of metals under various conditions. Section 4 describes the consequences of the presence of a prepulse before the main drilling pulse. In Section 5 we take a brief look at the plasma plume: how it can be useful, and how we can avoid it. Finally, Section 6 contains a couple of examples of machining non-metals. The laser system …
Date: April 2, 1999
Creator: Banks, P S; Feit, M D; Komashko, A; Perry, M D; Rubenchik, A M; Shirk, M et al.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 24, Number 14, Pages 2535-2804, April 2, 1999 (open access)

Texas Register, Volume 24, Number 14, Pages 2535-2804, April 2, 1999

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: April 2, 1999
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Western National Forests: A Cohesive Strategy is Needed to Address Catastrophic Wildfire Threats (open access)

Western National Forests: A Cohesive Strategy is Needed to Address Catastrophic Wildfire Threats

A chapter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on: (1) the extent and seriousness of forest-health-related problems in national forests in the interior West; (2) the status of efforts by the Forest Service to address the most serious of these problems; and (3) barriers to successfully addressing these problems and options for overcoming them."
Date: April 2, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Design of second generation Hanford tank corrosion monitoring system (open access)

Design of second generation Hanford tank corrosion monitoring system

The Hanford Site has 177 underground waste tanks that store approximately 253 million liters of radioactive waste from 50 years of plutonium production. Twenty-eight tanks have a double shell and are constructed of welded ASTM A537-Class 1 (UNS K02400), ASTM A515-Grade 60 (UNS K02401), or ASTM A516-Grade 60 (UNS K02100) material. The inner tanks of the double-shell tanks (DSTS) were stress relieved following fabrication. One hundred and forty-nine tanks have a single shell, also constructed of welded mild steel, but not stress relieved following fabrication. Tank waste is in liquid, solid, and sludge forms. Tanks also contain a vapor space above the solid and liquid waste regions. The composition of the waste varies from tank to tank but generally has a high pH (>12) and contains sodium nitrate, sodium hydroxide, sodium nitrite, and other minor radioactive constituents resulting from plutonium separation processes. Leaks began to appear in the single-shell tanks shortly after the introduction of nitrate-based wastes in the 1950s. Leaks are now confirmed or suspected to be present in a significant number of single-shell tanks. The probable modes of corrosion failures are reported as nitrate stress corrosion cracking (SCC) and pitting. Previous efforts to monitor internal corrosion of waste …
Date: April 2, 1998
Creator: Edgemon, G.L.
Object Type: Report
System: The UNT Digital Library