Local drainage analyses of the Paducah and Portsmouth Gaseous Diffusion Plants during an extreme storm

International Nuclear Information System (INIS)

Johnson, R.O.; Wang, J.C.; Lee, D.W.

1993-01-01

Local drainage analyses have been performed for the Paducah and Portsmouth Gaseous Diffusion Plants during an extreme storm having an approximate 10,000-yr recurrence interval. This review discusses the methods utilized to accomplish the analyses in accordance with US Department of Energy (DOE) design and evaluation guidelines, and summarizes trends, results, generalizations, and uncertainties applicable to other DOE facilities. Results indicate that some culverts may be undersized, and that the storm sewer system cannot drain the influx of precipitation from the base of buildings. Roofs have not been designed to sustain ponding when the primary drainage system is clogged. Some underground tunnels, building entrances, and ground level air intakes may require waterproofing

Environmental Restoration Site-Specific Plan for the Paducah Gaseous Diffusion Plant, FY 93

International Nuclear Information System (INIS)

1993-01-01

This report provides an overview of the major Environmental Restoration (ER) concerns at Paducah Gaseous Diffusion Plant (PGDP). The identified solid waste management units at PGDP are listed. In the Department of Energy (DOE) Five Year Plan development process, one or more waste management units are addressed in a series of activity data sheets (ADSs) which identify planned scope, schedule, and cost objectives that are representative of the current state of planned technical development for individual or multiple sites

PGDP [Paducah Gaseous Diffusion Plant]-UF6 handling, sampling, analysis and associated QC/QA and safety related procedures

International Nuclear Information System (INIS)

Harris, R.L.

1987-01-01

This document is a compilation of Paducah Gaseous Diffusion Plant procedures on UF 6 handling, sampling, and analysis, along with associated QC/QA and safety related procedures. It was assembled for transmission by the US Department of Energy to the Korean Advanced Energy Institute as a part of the US-Korea technical exchange program

Bioavailability study for the Paducah Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Phipps, T.L.; Kszos, L.A.

1996-08-01

The overall purpose of this plan is to assess the bioavailability of metals in the continuous and intermittent outfalls. The results may be used to determine alternative metal limits that more appropriately measure the portion of metal present necessary for toxicity to aquatic life. These limits must remain protective of in-stream aquatic life; thus, the highest concentration of metal in the water will be determined concurrently with an assessment of acute or chronic toxicity on laboratory tests. Using the method developed by the Kentucky Division of Water (KDOW), biomonitoring results and chemical data will be used to recommend alternative metal limits for the outfalls of concern. The data will be used to meet the objectives of the study: (1) evaluate the toxicity of continuous outfalls and intermittent outfalls at Paducah Gaseous Diffusion Plant; (2) determine the mean ratio of dissolved to Total Recoverable metal for Cd, Cr, Cu, Pb, Ni, and Zn in the continuous and intermittent outfalls; (3) determine whether the concentration of total recoverable metal discharged causes toxicity to fathead minnows and /or Ceriodaphnia; and (4) determine alternative metal limits for each metal of concern (Cd, Cr, Cu, Pb, Ni, and Zn).

An in situ survey of the Paducah Gaseous Diffusion Plant and surrounding area

International Nuclear Information System (INIS)

Hoover, R.A.

1994-02-01

An in situ survey of the area surrounding the Paducah Gaseous Diffusion Plant was conducted between May 17 and 24, 1990. The survey consisted of in situ measurements and of ground sampling. A High Purity Germanium detector was used for the in situ measurements. The ground samples were taken to the, laboratory at EG ampersand G Energy Measurements, Inc., in Santa Barbara, California, for a radionuclide assay on a laboratory system. Results of the in situ measurements found evidence of naturally occurring radioisotopes, cesium-137 from international fallout, and some evidence of anomalous uranium-238. The soil sampling results show only the presence of naturally occurring radioisotopes, cesium-137, and also anomalous uranium-238

Seismically-induced soil amplification at the DOE Paducah Gaseous Diffusion Plant site

International Nuclear Information System (INIS)

Sykora, D.W.; Haynes, M.E.

1991-01-01

A site-specific earthquake site response (soil amplification) study is being conducted for the Department of Energy (DOE), Paducah Gaseous Diffusion Plant (PGDP). This study is pursuant to an upgraded Final Safety Analysis Report in accordance with requirements specified by DOE. The seismic hazard at PGDP is dominated by the New Madrid Seismic Zone. Site-specific synthetic earthquake records developed by others were applied independently to four soil columns with heights above baserock of about 325 ft. The results for the 1000-year earthquake event indicate that the site period is between 1.0 and 1.5 sec. Incident shear waves are amplified at periods of motion greater than 0.15 sec. The peak free-field horizontal acceleration, occurring at very low periods, is 0.28 g. 13 refs., 13 figs

Seismically-induced soil amplification at the DOE Paducah Gaseous Diffusion Plant Site

International Nuclear Information System (INIS)

Sykora, D.W.; Hynes, M.E.; Brock, W.R.; Hunt, R.J.; Shaffer, K.E.

1991-01-01

A site-specific earthquake site response (soil amplification) study is being conducted for the Department of Energy (DOE), Paducah Gaseous Diffusion Plant (PGDP). This study is pursuant to an upgraded Final Safety Analysis Report in accordance with requirements specified by DOE. The seismic hazard at PGDP is dominated by the New Madrid Seismic Zone. Site-specific synthetic earthquake records developed by others were applied independently to four soil columns with heights above baserock of about 325 ft. The results for the 1000-year earthquake event indicate that the site period is between 1.0 and 1.5 sec. Incident shear waves are strongly amplified at periods of motion greater than 0.3 sec. The peak free-field horizontal acceleration, occurring at very low periods, is 0.28 g

Inorganic soil and groundwater chemistry near Paducah Gaseous Diffusion Plant, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

Moore, G.K. [Tennessee Univ., Knoxville, TN (United States)

1995-03-01

Near-surface soils, boreholes, and sediments near the Paducah Gaseous Diffusion Plant (PGDP) were sampled in 1989-91 as were monitoring wells, TVA wells, and privately-owned wells. Most wells were sampled two or three times. The resulting chemical analyses have been published in previous reports and have been previously described (CH2M HILL 1991, 1992; Clausen et al. 1992). The two reports by CH2M HILL are controversial, however, because, the concentrations of some constituents were reported to exceed background levels or drinking water standards and because both on-site (within the perimeter fence at PGDP) and off-site pollution was reported to have occurred. The groundwater samples upon which these interpretations were based may not be representative, however. The CH2M HILL findings are discussed in the report. The purpose of this report is to characterize the inorganic chemistry of groundwater and soils near PGDP, using data from the CH2M HILL reports (1991, 1992), and to determine whether or not any contamination has occurred. The scope is limited to analysis and interpretation of data in the CH2M HILL reports because previous interpretations of these data may not be valid, because samples were collected in a relatively short period of time at several hundred locations, and because the chemical analyses are nearly complete. Recent water samples from the same wells were not considered because the characterization of inorganic chemistry for groundwater and soil requirements only one representative sample and an accurate analysis from each location.

Inorganic soil and groundwater chemistry near Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

Moore, G.K.

1995-03-01

Near-surface soils, boreholes, and sediments near the Paducah Gaseous Diffusion Plant (PGDP) were sampled in 1989-91 as were monitoring wells, TVA wells, and privately-owned wells. Most wells were sampled two or three times. The resulting chemical analyses have been published in previous reports and have been previously described (CH2M HILL 1991, 1992; Clausen et al. 1992). The two reports by CH2M HILL are controversial, however, because, the concentrations of some constituents were reported to exceed background levels or drinking water standards and because both on-site (within the perimeter fence at PGDP) and off-site pollution was reported to have occurred. The groundwater samples upon which these interpretations were based may not be representative, however. The CH2M HILL findings are discussed in the report. The purpose of this report is to characterize the inorganic chemistry of groundwater and soils near PGDP, using data from the CH2M HILL reports (1991, 1992), and to determine whether or not any contamination has occurred. The scope is limited to analysis and interpretation of data in the CH2M HILL reports because previous interpretations of these data may not be valid, because samples were collected in a relatively short period of time at several hundred locations, and because the chemical analyses are nearly complete. Recent water samples from the same wells were not considered because the characterization of inorganic chemistry for groundwater and soil requirements only one representative sample and an accurate analysis from each location

Dual wall reverse circulation drilling with multi-level groundwater sampling for groundwater contaminant plume delineation at Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

Smuin, D.R.; Morti, E.E.; Zutman, J.L.; Pickering, D.A.

1995-01-01

Dual wall reverse circulation (DWRC) drilling was used to drill 48 borings during a groundwater contaminant investigation at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky. This method was selected as an alternative to conventional hollow stem auger drilling for a number of reasons, including the expectation of minimizing waste, increasing the drilling rate, and reducing the potential for cross contamination of aquifers. Groundwater samples were collected from several water-bearing zones during drilling of each borehole. The samples were analyzed for volatile organic compounds using a field gas chromatograph. This approach allowed the investigation to be directed using near-real-time data. Use of downhole geophysical logging, in conjunction with lithologic descriptions of borehole cuttings, resulted in excellent correlation of the geology in the vicinity of the contaminant plume. The total volume of cuttings generated using the DWRC drilling method was less than half of what would have been produced by hollow stem augering; however, the cuttings were recovered in slurry form and had to be dewatered prior to disposal. The drilling rate was very rapid, often approaching 10 ft/min; however, frequent breaks to perform groundwater sampling resulted in an average drilling rate of < 1 ft/min. The time required for groundwater sampling could be shortened by changing the sampling methodology. Analytical results indicated that the drilling method successfully isolated the various water bearing zones and no cross contamination resulted from the investigation

Paducah Site annual environmental report summary for 1994

International Nuclear Information System (INIS)

Horak, C.M.

1996-02-01

This pamphlet contains summaries of the environmental programs at the Paducah Gaseous Plant site, environmental monitoring and the results, and the impact of operations on the environment and the public for 1994

Paducah Gaseous Diffusion Plant Northwest Plume interceptor system evaluation

International Nuclear Information System (INIS)

Laase, A.D.; Clausen, J.L.

1998-01-01

The Paducah Gaseous Diffusion Plant (PGDP) recently installed an interceptor system consisting of four wells, evenly divided between two well fields, to contain the Northwest Plume. As stated in the Northwest Plume Record of Decision (ROD), groundwater will be pumped at a rate to reduce further contamination and initiate control of the northwest contaminant plume. The objective of this evaluation was to determine the optimum (minimal) well field pumping rates required for plume hotspot containment. Plume hotspot, as defined in the Northwest Plume ROD and throughout this report, is that portion of the plume with trichloroethene (TCE) concentrations greater than 1,000 microg/L. An existing 3-dimensional groundwater model was modified and used to perform capture zone analyses of the north and south interceptor system well fields. Model results suggest that the plume hotspot is not contained at the system design pumping rate of 100 gallons per minute (gal/min) per well field. Rather, the modeling determined that north and south well field pumping rates of 400 and 150 gal/min, respectively, are necessary for plume hotspot containment. The difference between the design and optimal pumping rates required for containment can be attributed to the discovery of a highly transmissive zone in the vicinity of the two well fields

Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

International Nuclear Information System (INIS)

1990-01-01

Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky. The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: an emergency management plan, with emphasis on the catastrophic earthquake; an Emergency Operations Center Duty Roster Manual; an Integrated Automated Emergency Management Information System (IAEMIS); and a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6, Volume III -- Chapter 7, and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume I, provides an introduction, summary and recommendations, and the emergency operations center direction and control

Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

International Nuclear Information System (INIS)

1990-01-01

Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP -- Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: (1) an emergency management plan with emphasis on the catas trophic earthquake; (2) an Emergency Operations Center Duty Roster Manual; (3) an Integrated Automated Emergency Management Information System (IAEMIS); and (4) a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6; Volume III -- Chapter 7; and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is this document numbered as Volume III

Environmental investigations at the Paducah Gaseous Diffusion Plant and surrounding area, McCracken County, Kentucky. Volume 1 - Executive summary. Final report

International Nuclear Information System (INIS)

1994-05-01

This report details the results of four studies into environmental and cultural resources on and near the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP) located in Western Kentucky in McCracken County, approximately 10 miles west of Paducah, KY. The area investigated includes the PGDP facility proper, additional area owned by DOE under use permit to the Western Kentucky Wildlife Management Area (WKWMA), area owned by the Commonwealth of Kentucky that is administered by the WKWMA, area owned by the Tennessee Valley Authority (TVA), the Metropolis Lake State Nature preserve and some privately held land. DOE requested the assistance and support of the US Army Engineer District, Nashville (CEORN) in conducting various environmental investigations of the area. The US Army Engineer Waterways Experiment Station (WES) provided technical support to the CEORN for environmental investigations of (1) wetland resources, (2) threatened or endangered species and habitats, and (3) cultural resources. A floodplain investigation was conducted by CEORN

Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

International Nuclear Information System (INIS)

1990-01-01

Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP -- Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: an emergency management plan, with emphasis on the catastrophic earthquake; an Emergency Operations Center Duty Roster Manual; an Integrated Automated Emergency Management Information System (IAEMIS); and a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6, Volume III -- Chapter 7, and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume II, discusses methodology, engineering and environmental analyses, and operational procedures

Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

International Nuclear Information System (INIS)

1990-01-01

Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc, initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP--Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: (1) an emergency management plan, with emphasis on the catas trophic earthquake, (2) an Emergency Operations Center Duty Roster Manual, (3) an Integrated Automated Emergency Management Information System (IAEMIS), and (4) a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I--Chapters 1--3; Volume II--Chapters 4--6, Volume III--Chapter 7, and Volume IV--23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume IV contains the appendices to this report

OCCUPATIONAL EXPOSURE TO TRICHLOROETHYLENE AND CANCER RISK FOR WORKERS AT THE PADUCAH GASEOUS DIFFUSION PLANT

Science.gov (United States)

BAHR, DEBRA E.; ALDRICH, TIMOTHY E.; SEIDU, DAZAR; BRION, GAIL M.; TOLLERUD, DAVID J.; MULDOON, SUSAN; REINHART, NANCY; YOUSEEFAGHA, AHMED; MCKINNEY, PAUL; HUGHES, THERESE; CHAN, CAROLINE; RICE, CAROL; BREWER, DAVID E.; FREYBERG, RONALD W.; MOHLENKAMP, ADRIANE MOSER; HAHN, KRISTEN; HORNUNG, RICHARD; HO, MONA; DASTIDAR, ANIRUDDHA; FREITAS, SAMANTHA; SAMAN, DANIEL; RAVDAL, HEGE; SCUTCHFIELD, DOUGLAS; EGER, KENNETH J.; MINOR, STEVE

2016-01-01

Objective The Paducah Gaseous Diffusion Plant (PGDP) became operational in 1952; it is located in the western part of Kentucky. We conducted a mortality study for adverse health effects that workers may have suffered while working at the plant, including exposures to chemicals. Materials and Methods We studied a cohort of 6820 workers at the PGDP for the period 1953 to 2003; there were a total of 1672 deaths to cohort members. Trichloroethylene (TCE) is a specific concern for this workforce; exposure to TCE occurred primarily in departments that clean the process equipment. The Life Table Analysis System (LTAS) program developed by NIOSH was used to calculate the standardized mortality ratios for the worker cohort and standardized rate ratio relative to exposure to TCE (the U.S. population is the referent for age-adjustment). LTAS calculated a significantly low overall SMR for these workers of 0.76 (95% CI: 0.72–0.79). A further review of three major cancers of interest to Kentucky produced significantly low SMR for trachea, bronchus, lung cancer (0.75, 95% CI: 0.72–0.79) and high SMR for Non-Hodgkin's lymphoma (NHL) (1.49, 95% CI: 1.02–2.10). Results No significant SMR was observed for leukemia and no significant SRRs were observed for any disease. Both the leukemia and lung cancer results were examined and determined to reflect regional mortality patterns. However, the Non-Hodgkin's Lymphoma finding suggests a curious amplification when living cases are included with the mortality experience. Conclusions Further examination is recommended of this recurrent finding from all three U.S. Gaseous Diffusion plants. PMID:21468904

Paducah Site annual report for 1995

Energy Technology Data Exchange (ETDEWEB)

Belcher, G. [ed.

1997-01-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US department of Energy (DOE) leased the production areas of the site to the US Enrichment Corporation (USEC). A new subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. DOE maintains responsibility for the environmental restoration, waste management, and enrichment facilities activities at the plant through its management contractor, Lockheed Martin Energy Systems. The purpose of this document is to summarize calendar year 1995 environmental monitoring activities for DOE activities at the Paducah Site. DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities.

Paducah Site annual report for 1995

International Nuclear Information System (INIS)

Belcher, G.

1997-01-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US department of Energy (DOE) leased the production areas of the site to the US Enrichment Corporation (USEC). A new subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. DOE maintains responsibility for the environmental restoration, waste management, and enrichment facilities activities at the plant through its management contractor, Lockheed Martin Energy Systems. The purpose of this document is to summarize calendar year 1995 environmental monitoring activities for DOE activities at the Paducah Site. DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities

Proposed sale of radioactively contaminated nickel ingots located at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

1995-10-01

The U.S. Department of Energy (DOE) proposes to sell 8,500 radioactively contaminated nickel ingots (9.350 short tons), currently in open storage at the Paducah Gaseous Diffusion Plant (PGDP), to Scientific Ecology Group, Inc. (SEG) for decontamination and resale on the international market. SEG would take ownership of the ingots when they are loaded for transport by truck to its facility in Oak Ridge, Tennessee. SEG would receive approximately 200 short tons per month over approximately 48 months (an average of 180 ingots per month). The nickel decontamination process specified in SEG's technical proposal is considered the best available technology and has been demonstrated in prototype at SEG. The resultant metal for resale would have contamination levels between 0.3 and 20 becquerel per gram (Bq/g). The health hazards associated with release of the decontaminated nickel are minimal. The activity concentration of the end product would be further reduced when the nickel is combined with other metals to make stainless steel. Low-level radioactive waste from the SEG decontamination process, estimated to be approximately 382 m 3 (12,730 ft), would be shipped to a licensed commercial or DOE disposal facility. If the waste were packaged in 0.23 m 3 -(7.5 ft 3 -) capacity drums, approximately 1,500 to 1,900 drums would be transported over the 48-month contract period. Impacts from the construction of decontamination facilities and the selected site are minimal

Paducah site annual environmental for 1996

Energy Technology Data Exchange (ETDEWEB)

Belcher, G. [ed.

1997-12-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US Department of Energy (DOE) leased the production areas of the site to the United States Enrichment Corporation (USEC). A subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. The DOE maintains responsibility for the environmental restoration, waste management, and depleted uranium hexafluoride cylinder program activities at the plant through its management contractor, Lockheed Martin Energy Systems. The purpose of this document is to summarize calendar year 1996 environmental monitoring activities for DOE activities at the Paducah Site. The DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities.

Paducah Site 1997 annual environmental report

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US Department of Energy (DOE) leased the production areas of the site to the US Enrichment Corporation (USEC). A subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. The DOE maintains responsibility for the environmental restoration, waste management, and depleted uranium hexafluoride cylinder program activities at the plant through its management contractor. The purpose of this document is to summarize calendar year 1997 environmental monitoring activities for DOE activities at the Paducah Site managed by Lockheed Martin Energy Systems. The DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities.

Paducah Site 1997 annual environmental report

International Nuclear Information System (INIS)

1998-12-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US Department of Energy (DOE) leased the production areas of the site to the US Enrichment Corporation (USEC). A subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. The DOE maintains responsibility for the environmental restoration, waste management, and depleted uranium hexafluoride cylinder program activities at the plant through its management contractor. The purpose of this document is to summarize calendar year 1997 environmental monitoring activities for DOE activities at the Paducah Site managed by Lockheed Martin Energy Systems. The DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities

Paducah Site annual environmental report for 1994

International Nuclear Information System (INIS)

Horak, C.M.

1996-02-01

Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US Department of Energy (DOE) leased the production areas of the site to the United States Enrichment Corporation (USEC). A new subsidiary of Lockheed Martin Corporation (formerly Martin Marietta Corporation), Lockheed Martin Utility Services, manages the leased facilities for USEC. DOE maintains responsibility for the environmental restoration and waste management activities at the plant through its management contractor, Lockheed Martin Energy Systems. The purpose of this document is to summarize calendar year 1994 environmental monitoring activities for DOE activities at the Paducah site. DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities

Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant December 1992--December 1993

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A.; Hinzman, R.L.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

1995-06-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The goals of BMP are to demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, characterize potential health and environmental impacts, document the effects of pollution abatement facilities on stream biota, and recommend any program improvements that would increase effluent treatability. The BMP for PGDP consists of three major tasks: effluent and ambient toxicity monitoring, bioaccumulation studies, and ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1992 to December 1993, although activities conducted outside this time period are included as appropriate.

Paducah site annual environmental report for 1996

International Nuclear Information System (INIS)

Belcher, G.

1997-12-01

The Paducah Gaseous Diffusion Plant, located in McCracken County, Kentucky, has been producing enriched uranium since 1952. In July 1993, the US Department of Energy (DOE) leased the production areas of the site to the United States Enrichment Corporation (USEC). A subsidiary of Lockheed Martin Corporation, Lockheed Martin Utility Services, manages the leased facilities for USEC. The DOE maintains responsibility for the environmental restoration, waste management, and depleted uranium hexafluoride cylinder program activities at the plant through its management contractor, Lockheed Martin Energy Systems. The purpose of this document is to summarize calendar year 1996 environmental monitoring activities for DOE activities at the Paducah Site. The DOE requires all of its facilities to conduct and document such activities annually. This report does not include USEC environmental activities

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January--December 1996

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A. [ed.; Konetsky, B.K.; Peterson, M.J.; Petrie, R.B.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

1997-06-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous diffusion Plant (PGDP). The PGDP BMP was conducted by the University of Kentucky Between 1987 and 1992 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 to present. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, and (3) document the effects of pollution abatement facilities on stream. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report focuses on ESD activities occurring from January 1996 to December 1996, although activities conducted outside this time period are included as appropriate.

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January - December 1996

International Nuclear Information System (INIS)

Kszos, L.A.; Konetsky, B.K.; Peterson, M.J.; Petrie, R.B.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

1997-06-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous diffusion Plant (PGDP). The PGDP BMP was conducted by the University of Kentucky Between 1987 and 1992 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 to present. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, and (3) document the effects of pollution abatement facilities on stream. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report focuses on ESD activities occurring from January 1996 to December 1996, although activities conducted outside this time period are included as appropriate

LANMAS alpha configured for Sandia National Laboratories and Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Woychick, M.R.; Bracey, J.T.; Kern, E.A.; Alvarado, A.

1993-07-01

Los Alamos National Laboratory and the Westinghouse Hanford Company have been working jointly for the past 2 years to develop LANMAS (Local Area Network Material Accountability System), the next generation of a US Department of Energy nuclear material accountability system. LANMAS is being designed to reflect the broad-based needs of the US Department of Energy's Material Control ampersand Accountability and Nuclear Materials Management communities, and its developers believe that significant cost savings can be achieved by implementing LANMAS complex-wide, where feasible. LANMAS is being designed so that it is transportable to appropriate US Department of Energy sites. To accomplish this, LANMAS will be configurable to local site work culture. Many US Department of Energy sites are interested in the LANMAS project, and several have participated in its development; some have committed resources. The original LANMAS project team included representatives from the Hanford Site and Los Alamos. As of June 1993, the following sites have also supported the project: Sandia National Laboratory Albuquerque; Sandia National Laboratory Livermore; Paducah Gaseous Diffusion Plant; Lawrence Livermore National Laboratory; Bettis Atomic Power Laboratory; and Knolls Atomic Power Laboratory. In addition, LANMAS is being targeted as a candidate for the US Department of Energy Complex 21, a project designed to restructure the nation's nuclear weapons complex

Dose Modeling Evaluations and Technical Support Document For the Authorized Limits Request for the DOE-Owned Property Outside the Limited Area, Paducah Gaseous Diffusion Plant Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

Boerner, A. J. [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program; Maldonado, D. G. [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program; Hansen, Tom [Ameriphysics, LLC (United States)

2012-09-01

Environmental assessments and remediation activities are being conducted by the U.S. Department of Energy (DOE) at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky. The Oak Ridge Institute for Science and Education (ORISE), a DOE prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct radiation dose modeling analyses and derive single radionuclide soil guidelines (soil guidelines) in support of the derivation of Authorized Limits (ALs) for 'DOE-Owned Property Outside the Limited Area' ('Property') at the PGDP. The ORISE evaluation specifically included the area identified by DOE restricted area postings (public use access restrictions) and areas licensed by DOE to the West Kentucky Wildlife Management Area (WKWMA). The licensed areas are available without restriction to the general public for a variety of (primarily) recreational uses. Relevant receptors impacting current and reasonably anticipated future use activities were evaluated. In support of soil guideline derivation, a Conceptual Site Model (CSM) was developed. The CSM listed radiation and contamination sources, release mechanisms, transport media, representative exposure pathways from residual radioactivity, and a total of three receptors (under present and future use scenarios). Plausible receptors included a Resident Farmer, Recreational User, and Wildlife Worker. single radionuclide soil guidelines (outputs specified by the software modeling code) were generated for three receptors and thirteen targeted radionuclides. These soil guidelines were based on satisfying the project dose constraints. For comparison, soil guidelines applicable to the basic radiation public dose limit of 100 mrem/yr were generated. Single radionuclide soil guidelines from the most limiting (restrictive) receptor based on a target dose constraint of 25 mrem/yr were then rounded and identified as the derived soil guidelines. An additional evaluation using the derived soil

Dose Modeling Evaluations and Technical Support Document For the Authorized Limits Request for the DOE-Owned Property Outside the Limited Area, Paducah Gaseous Diffusion Plant Paducah, Kentucky

International Nuclear Information System (INIS)

Boerner, A. J.

2012-01-01

Environmental assessments and remediation activities are being conducted by the U.S. Department of Energy (DOE) at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky. The Oak Ridge Institute for Science and Education (ORISE), a DOE prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct radiation dose modeling analyses and derive single radionuclide soil guidelines (soil guidelines) in support of the derivation of Authorized Limits (ALs) for 'DOE-Owned Property Outside the Limited Area' ('Property') at the PGDP. The ORISE evaluation specifically included the area identified by DOE restricted area postings (public use access restrictions) and areas licensed by DOE to the West Kentucky Wildlife Management Area (WKWMA). The licensed areas are available without restriction to the general public for a variety of (primarily) recreational uses. Relevant receptors impacting current and reasonably anticipated future use activities were evaluated. In support of soil guideline derivation, a Conceptual Site Model (CSM) was developed. The CSM listed radiation and contamination sources, release mechanisms, transport media, representative exposure pathways from residual radioactivity, and a total of three receptors (under present and future use scenarios). Plausible receptors included a Resident Farmer, Recreational User, and Wildlife Worker. single radionuclide soil guidelines (outputs specified by the software modeling code) were generated for three receptors and thirteen targeted radionuclides. These soil guidelines were based on satisfying the project dose constraints. For comparison, soil guidelines applicable to the basic radiation public dose limit of 100 mrem/yr were generated. Single radionuclide soil guidelines from the most limiting (restrictive) receptor based on a target dose constraint of 25 mrem/yr were then rounded and identified as the derived soil guidelines. An additional evaluation using the derived soil

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1993 to December 1994

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A. [ed.

1996-05-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The PGDP BMP was implemented in 1987 by the University of Kentucky. Research staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) served as reviewers and advisers to the University of Kentucky. Beginning in fall 1991, ESD added data collection and report preparation to its responsibilities for the PGDP BMP. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, (3) document the effects of pollution abatement facilities on stream biota, and (4) recommend any program improvements that would increase effluent treatability. In September 1992, a renewed Kentucky Pollutant Discharge Elimination System (KPDES) permit was issued to PGDP. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1993 to December 1994, although activities conducted outside this time period are included as appropriate.

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1993 to December 1994

International Nuclear Information System (INIS)

Kszos, L.A.

1996-05-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The PGDP BMP was implemented in 1987 by the University of Kentucky. Research staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) served as reviewers and advisers to the University of Kentucky. Beginning in fall 1991, ESD added data collection and report preparation to its responsibilities for the PGDP BMP. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, (3) document the effects of pollution abatement facilities on stream biota, and (4) recommend any program improvements that would increase effluent treatability. In September 1992, a renewed Kentucky Pollutant Discharge Elimination System (KPDES) permit was issued to PGDP. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1993 to December 1994, although activities conducted outside this time period are included as appropriate

Dispersion of UO2F2 aerosol and HF vapor in the operating floor during winter ventilation at the Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Kim, S.H.; Chen, N.C.J.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.; Carter, J.C.

1996-01-01

The gaseous diffusion process is currently employed at two plants in the US: the Paducah Gaseous Diffusion Plant and the Portsmouth Gaseous Diffusion Plant. As part of a facility-wide safety evaluation, a postulated design basis accident involving large line-rupture induced releases of uranium hexafluoride (UF 6 ) into the process building of a gaseous diffusion plant (GDP) is evaluated. When UF 6 is released into the atmosphere, it undergoes an exothermic chemical reaction with moisture (H 2 O) in the air to form vaporized hydrogen fluoride (HF) and aerosolized uranyl fluoride (UO 2 F 2 ). These reactants disperse in the process building and transport through the building ventilation system. The ventilation system draws outside air into the process building, distributes it evenly throughout the building, and discharges it to the atmosphere at an elevated temperature. Since air is recirculated from the cell floor area to the operating floor, issues concerning in-building worker safety and evacuation need to be addressed. Therefore, the objective of this study is to evaluate the transport of HF vapor and UO 2 F 2 aerosols throughout the operating floor area following B-line break accident in the cell floor area

Independent Technical Review Of The Focused Feasibility Study And Proposed Plan For Designated Solid Waste Management Units Contributing To The Southwest Groundwater Plume At The Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Looney, B.; Eddy-Dilek, C.; Amidon, M.; Rossabi, J.; Stewart, L.

2011-01-01

The U. S. Department of Energy (DOE) is currently developing a Proposed Plan (PP) for remediation of designated sources of chlorinated solvents that contribute contamination to the Southwest (SW) Groundwater Plume at the Paducah Gaseous Diffusion Plant (PGDP), in Paducah, KY. The principal contaminants in the SW Plume are trichloroethene (TCE) and other volatile organic compounds (VOCs); these industrial solvents were used and disposed in various facilities and locations at PGDP. In the SW plume area, residual TCE sources are primarily in the fine-grained sediments of the Upper Continental Recharge System (UCRS), a partially saturated zone that delivers contaminants downward into the coarse-grained Regional Gravel Aquifer (RGA). The RGA serves as the significant lateral groundwater transport pathway for the plume. In the SW Plume area, the four main contributing TCE source units are: (1) Solid Waste Management Unit (SWMU) 1 / Oil Landfarm; (2) C-720 Building TCE Northeast Spill Site (SWMU 211A); (3) C-720 Building TCE Southeast Spill Site (SWMU 211B); and (4) C-747 Contaminated Burial Yard (SWMU 4). The PP presents the Preferred Alternatives for remediation of VOCs in the UCRS at the Oil Landfarm and the C-720 Building spill sites. The basis for the PP is documented in a Focused Feasibility Study (FFS) (DOE, 2011) and a Site Investigation Report (SI) (DOE, 2007). The SW plume is currently within the boundaries of PGDP (i.e., does not extend off-site). Nonetheless, reasonable mitigation of the multiple contaminant sources contributing to the SW plume is one of the necessary components identified in the PGDP End State Vision (DOE, 2005). Because of the importance of the proposed actions DOE assembled an Independent Technical Review (ITR) team to provide input and assistance in finalizing the PP.

INDEPENDENT TECHNICAL REVIEW OF THE FOCUSED FEASIBILITY STUDY AND PROPOSED PLAN FOR DESIGNATED SOLID WASTE MANAGEMENT UNITS CONTRIBUTING TO THE SOUTHWEST GROUNDWATER PLUME AT THE PADUCAH GASEOUS DIFFUSION PLANT

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Eddy-Dilek, C.; Amidon, M.; Rossabi, J.; Stewart, L.

2011-05-31

The U. S. Department of Energy (DOE) is currently developing a Proposed Plan (PP) for remediation of designated sources of chlorinated solvents that contribute contamination to the Southwest (SW) Groundwater Plume at the Paducah Gaseous Diffusion Plant (PGDP), in Paducah, KY. The principal contaminants in the SW Plume are trichloroethene (TCE) and other volatile organic compounds (VOCs); these industrial solvents were used and disposed in various facilities and locations at PGDP. In the SW plume area, residual TCE sources are primarily in the fine-grained sediments of the Upper Continental Recharge System (UCRS), a partially saturated zone that delivers contaminants downward into the coarse-grained Regional Gravel Aquifer (RGA). The RGA serves as the significant lateral groundwater transport pathway for the plume. In the SW Plume area, the four main contributing TCE source units are: (1) Solid Waste Management Unit (SWMU) 1 / Oil Landfarm; (2) C-720 Building TCE Northeast Spill Site (SWMU 211A); (3) C-720 Building TCE Southeast Spill Site (SWMU 211B); and (4) C-747 Contaminated Burial Yard (SWMU 4). The PP presents the Preferred Alternatives for remediation of VOCs in the UCRS at the Oil Landfarm and the C-720 Building spill sites. The basis for the PP is documented in a Focused Feasibility Study (FFS) (DOE, 2011) and a Site Investigation Report (SI) (DOE, 2007). The SW plume is currently within the boundaries of PGDP (i.e., does not extend off-site). Nonetheless, reasonable mitigation of the multiple contaminant sources contributing to the SW plume is one of the necessary components identified in the PGDP End State Vision (DOE, 2005). Because of the importance of the proposed actions DOE assembled an Independent Technical Review (ITR) team to provide input and assistance in finalizing the PP.

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1990 to November 1992

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A. [ed.

1994-03-01

On September 23, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Lab (ORNL) added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in identifying those effluents with the potential for adversely affecting instream fauna, assessing the ecological health of receiving streams, guiding plans for remediation, and protecting human health. In September 1992, a renewed permit was issued which requires toxicity monitoring of continuous and intermittent outfalls on a quarterly basis. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities. This report includes ESD/ORNL activities occurring from December 1990 to November 1992.

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1990 to November 1992

International Nuclear Information System (INIS)

Kszos, L.A.

1994-03-01

On September 23, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Lab (ORNL) added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in identifying those effluents with the potential for adversely affecting instream fauna, assessing the ecological health of receiving streams, guiding plans for remediation, and protecting human health. In September 1992, a renewed permit was issued which requires toxicity monitoring of continuous and intermittent outfalls on a quarterly basis. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities. This report includes ESD/ORNL activities occurring from December 1990 to November 1992

Review of earthquake hazard assessments of plant sites at Paducah, Kentucky and Portsmouth, Ohio

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

Members of the US Geological Survey staff in Golden, Colorado, have reviewed the submissions of Lawrence Livermore National Laboratory (LLNL) staff and of Risk Engineering, Inc. (REI) (Golden, Colorado) for seismic hazard estimates for Department of Energy facilities at Portsmouth, Ohio, and Paducah, Kentucky. We reviewed the historical seismicity and seismotectonics near the two sites, and general features of the LLNL and EPRI/SOG methodologies used by LLNL and Risk Engineering respectively, and also the separate Risk Engineering methodology used at Paducah. We discussed generic issues that affect the modeling of both sites, and performed alternative calculations to determine sensitivities of seismic hazard results to various assumptions and models in an attempt to assign reasonable bounding values of the hazard. In our studies we find that peak acceleration values of 0.08 g for Portsmouth and 0.32 g for Paducah represent central values of the, ground motions obtained at 1000-year return periods. Peak accelerations obtained in the LLNL and Risk Engineering studies have medians near these values (results obtained using the EPRI/SOG methodology appear low at both sites), and we believe that these medians are appropriate values for use in the evaluation of systems, structures, and components for seismic structural integrity and for the seismic design of new and improved systems, structures, and components at Portsmouth and Paducah.

Review of earthquake hazard assessments of plant sites at Paducah, Kentucky, and Portsmouth, Ohio

International Nuclear Information System (INIS)

1992-03-01

Members of the US Geological Survey staff in Golden, Colorado, have reviewed the submissions of Lawrence Livermore National Laboratory (LLNL) staff and of Risk Engineering, Inc. (REI) (Golden, Colorado) for seismic hazard estimates for Department of Energy facilities at Portsmouth, Ohio, and Paducah, Kentucky. We reviewed the historical seismicity and seismotectonics near the two sites, and general features of the LLNL and EPRI/SOG methodologies used by LLNL and Risk Engineering respectively, and also the separate Risk Engineering methodology used at Paducah. We discussed generic issues that affect the modeling of both sites, and performed alternative calculations to determine sensitivities of seismic hazard results to various assumptions and models in an attempt to assign reasonable bounding values of the hazard. In our studies we find that peak acceleration values of 0.08 g for Portsmouth and 0.32 g for Paducah represent central values of the ground motions obtained at 1000-year return periods. Peak accelerations obtained in the LLNL and Risk Engineering studies have medians near these values (results obtained using the EPRI/SOG methodology appear low at both sites), and we believe that these medians are appropriate values for use in the evaluation of systems, structures, and components for seismic structural integrity and for the seismic design of new and improved systems, structures, and components at Portsmouth and Paducah

Review of earthquake hazard assessments of plant sites at Paducah, Kentucky and Portsmouth, Ohio

International Nuclear Information System (INIS)

1997-01-01

Members of the US Geological Survey staff in Golden, Colorado, have reviewed the submissions of Lawrence Livermore National Laboratory (LLNL) staff and of Risk Engineering, Inc. (REI) (Golden, Colorado) for seismic hazard estimates for Department of Energy facilities at Portsmouth, Ohio, and Paducah, Kentucky. We reviewed the historical seismicity and seismotectonics near the two sites, and general features of the LLNL and EPRI/SOG methodologies used by LLNL and Risk Engineering respectively, and also the separate Risk Engineering methodology used at Paducah. We discussed generic issues that affect the modeling of both sites, and performed alternative calculations to determine sensitivities of seismic hazard results to various assumptions and models in an attempt to assign reasonable bounding values of the hazard. In our studies we find that peak acceleration values of 0.08 g for Portsmouth and 0.32 g for Paducah represent central values of the, ground motions obtained at 1000-year return periods. Peak accelerations obtained in the LLNL and Risk Engineering studies have medians near these values (results obtained using the EPRI/SOG methodology appear low at both sites), and we believe that these medians are appropriate values for use in the evaluation of systems, structures, and components for seismic structural integrity and for the seismic design of new and improved systems, structures, and components at Portsmouth and Paducah

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January--December 1997

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

1998-03-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). A plan for the biological monitoring of the receiving streams was implemented in 1987 and consisted of ecological surveys, toxicity monitoring of effluents and receiving streams, evaluation of bioaccumulation of trace contaminants in biota, and supplemental chemical characterization of effluents. Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in (1) identifying those effluents with the potential for adversely affecting instream fauna, (2) assessing the ecological health of receiving streams, and (3) guiding plans for remediation and protecting human health. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of benthic macroinvertebrate communities and fish. With the exception of the benthic macroinvertebrate community surveys, this report focuses on activities from January to December 1997.

Operating limit study for the proposed solid waste landfill at Paducah Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Lee, D.W.; Wang, J.C.; Kocher, D.C.

1995-06-01

A proposed solid waste landfill at Paducah Gaseous Diffusion Plant (PGDP) would accept wastes generated during normal operations that are identified as non-radioactive. These wastes may include small amounts of radioactive material from incidental contamination during plant operations. A site-specific analysis of the new solid waste landfill is presented to determine a proposed operating limit that will allow for waste disposal operations to occur such that protection of public health and the environment from the presence of incidentally contaminated waste materials can be assured. Performance objectives for disposal were defined from existing regulatory guidance to establish reasonable dose limits for protection of public health and the environment. Waste concentration limits were determined consistent with these performance objectives for the protection of off-site individuals and inadvertent intruders who might be directly exposed to disposed wastes. Exposures of off-site individuals were estimated using a conservative, site-specific model of the groundwater transport of contamination from the wastes. Direct intrusion was analyzed using an agricultural homesteader scenario. The most limiting concentrations from direct intrusion or groundwater transport were used to establish the concentration limits for radionuclides likely to be present in PGDP wastes.

Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January-December 1997

International Nuclear Information System (INIS)

Kszos, L.A.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

1998-03-01

On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). A plan for the biological monitoring of the receiving streams was implemented in 1987 and consisted of ecological surveys, toxicity monitoring of effluents and receiving streams, evaluation of bioaccumulation of trace contaminants in biota, and supplemental chemical characterization of effluents. Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in (1) identifying those effluents with the potential for adversely affecting instream fauna, (2) assessing the ecological health of receiving streams, and (3) guiding plans for remediation and protecting human health. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of benthic macroinvertebrate communities and fish. With the exception of the benthic macroinvertebrate community surveys, this report focuses on activities from January to December 1997

Operating limit study for the proposed solid waste landfill at Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Lee, D.W.; Wang, J.C.; Kocher, D.C.

1995-06-01

A proposed solid waste landfill at Paducah Gaseous Diffusion Plant (PGDP) would accept wastes generated during normal operations that are identified as non-radioactive. These wastes may include small amounts of radioactive material from incidental contamination during plant operations. A site-specific analysis of the new solid waste landfill is presented to determine a proposed operating limit that will allow for waste disposal operations to occur such that protection of public health and the environment from the presence of incidentally contaminated waste materials can be assured. Performance objectives for disposal were defined from existing regulatory guidance to establish reasonable dose limits for protection of public health and the environment. Waste concentration limits were determined consistent with these performance objectives for the protection of off-site individuals and inadvertent intruders who might be directly exposed to disposed wastes. Exposures of off-site individuals were estimated using a conservative, site-specific model of the groundwater transport of contamination from the wastes. Direct intrusion was analyzed using an agricultural homesteader scenario. The most limiting concentrations from direct intrusion or groundwater transport were used to establish the concentration limits for radionuclides likely to be present in PGDP wastes

Determination of operating limits for radionuclides for a proposed landfill at Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Wang, J.C.; Lee, D.W.; Ketelle, R.H.; Lee, R.R.; Kocher, D.C.

1994-01-01

The operating limits for radionuclides in sanitary and industrial wastes were determined for a proposed landfill at the Paducah Gaseous Diffusion Plant (PGDP), Kentucky. These limits, which may be very small but nonzero, are not mandated by law or regulation but are needed for rational operation. The approach was based on analyses of the potential contamination of groundwater at the plant boundary and the potential exposure to radioactivity of an intruder at the landfill after closure. The groundwater analysis includes (1) a source model describing the disposal of waste and the release of radionuclides from waste to the groundwater, (2) site-specific groundwater flow and contaminant transport calculations, and (3) calculations of operating limits from the dose limit and conversion factors. The intruder analysis includes pathways through ingestion of contaminated vegetables and soil, external exposure to contaminated soil, and inhalation of suspended activity from contaminated soil particles. In both analyses, a limit on annual effective dose equivalent of 4 mrem (0.04 mSv) was adopted. The intended application of the results is to refine the radiological monitoring standards employed by the PGDP Health Physics personnel to determine what constitutes radioactive wastes, with concurrence of the Commonwealth of Kentucky

Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Taylor, F.G.; Hanna, S.R.; Parr, P.D.

1979-01-01

The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified at the Department of Energy's uranium enrichment facility at Paducah, Kentucky. Chromium concentrations in plant materials (fescue grass) decreased with increasing distance from the cooing tower, ranging from 251 +- 19 ppM at 15 meters to 0.52 +- 0.07 ppM at 1500 meters. The site of drift contamination, size characteristics, and elemental content of drift particles were determined using a scanning electron microscope with energy dispersive x-ray analysis capabilities. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. A laboratory study simulating throughfall from 1 to 6 inches of rain suggested that there are more exchange sites associated with litter than live foliage. Leachate from each one inch throughfall simulant removed 3% of the drift mass from litter compared to 7 to 9% from live foliage. Results suggest that differences in retention are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil--water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Samples from two depths following rainstorms revealed the absence of vertical or horizontal movement with maximum concentrations of 0.13 ppb at 50 meters from the tower. Preliminary model estimates of drift deposition are compared to depositionmeasurements. Isopleths of the predicted deposition are useful to identify areas of maximum drift transport in the environs of the gaseous diffusion plant

77 FR 51789 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-08-27

... management and related activities. Tentative Agenda Call to Order, Introductions, Review of Agenda... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act...

Assessment and interpretation of cross- and down-hole seismograms at the Paducah Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Staub, W.P.; Wang, J.C. (Oak Ridge National Lab., TN (United States)); Selfridge, R.J. (Automated Sciences Group, (United States))

1991-09-01

This paper is an assessment and interpretation of cross-and down-hole seismograms recorded at four sites in the vicinity of the Paducah Gaseous Diffusion Plant (PGDP). Arrival times of shear (S-) and compressional (P-) waves are recorded on these seismograms in milliseconds. Together with known distances between energy sources and seismometers lowered into boreholes, these arrival times are used to calculate S- and P-wave velocities in unconsolidated soils and sediments that overlie bedrock approximately 320 ft beneath PGDP. The soil columns are modified after an earlier draft by ERC Environmental and Energy Services Company (ERCE), 1990. In addition to S- and P- wave velocity estimates from this paper, the soil columns contain ERCE's lithologic and other geotechnical data for unconsolidated soils and sediments from the surface to bedrock. Soil columns for Sites 1 through 4 and a site location map are in Plates 1 through 5 of Appendix 6. The velocities in the four columns are input parameters for the SHAKE computer program, a nationally recognized computer model that simulates ground response of unconsolidated materials to earthquake generated seismic waves. The results of the SHAKE simulation are combined with predicted ground responses on rock foundations (caused by a given design earthquake) to predict ground responses of facilities with foundations placed on unconsolidated materials. 3 refs.

Environmental assessment for the construction and operation of waste storage facilities at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-06-01

DOE is proposing to construct and operate 3 waste storage facilities (one 42,000 ft{sup 2} waste storage facility for RCRA waste, one 42,000 ft{sup 2} waste storage facility for toxic waste (TSCA), and one 200,000 ft{sup 2} mixed (hazardous/radioactive) waste storage facility) at Paducah. This environmental assessment compares impacts of this proposed action with those of continuing present practices aof of using alternative locations. It is found that the construction, operation, and ultimate closure of the proposed waste storage facilities would not significantly affect the quality of the human environment within the meaning of NEPA; therefore an environmental impact statement is not required.

Environmental assessment for the construction and operation of waste storage facilities at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

1994-06-01

DOE is proposing to construct and operate 3 waste storage facilities (one 42,000 ft 2 waste storage facility for RCRA waste, one 42,000 ft 2 waste storage facility for toxic waste (TSCA), and one 200,000 ft 2 mixed (hazardous/radioactive) waste storage facility) at Paducah. This environmental assessment compares impacts of this proposed action with those of continuing present practices aof of using alternative locations. It is found that the construction, operation, and ultimate closure of the proposed waste storage facilities would not significantly affect the quality of the human environment within the meaning of NEPA; therefore an environmental impact statement is not required

The Blend Down Monitoring System Demonstration at the Padijcah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Benton, J.; Close, D.; Johnson, W. Jr.; Kerr, P.; March-Leuba, J.; Mastal, E.; Moss, C.; Powell, D.; Sumner, J.; Uckan, T.; Vines, R.; Wright, P.D.

1999-01-01

Agreements between the governments of the US and the Russian Federation for the US purchase of low enriched uranium (LEU) derived from highly enriched uranium (HEU) from dismantled Russian nuclear weapons calls for the establishment of transparency measures to provide confidence that nuclear nonproliferation goals are being met. To meet these transparency goals, the agreements call for the installation of nonintrusive US instruments to monitor the down blending of HEU to LEU. The Blend Down Monitoring System (BDMS) has been jointly developed by the Los Alamos National Laboratory (LANL) and the Oak Ridge National Laboratory (ORNL) to continuously monitor 235 U enrichments and mass flow rates at Russian blending facilities. Prior to its installation in Russian facilities, the BDMS was installed and operated in a UF 6 flow loop in the Paducah Gaseous Diffusion Plant simulating flow and enrichment conditions expected in a typical down-blending facility. A Russian delegation to the US witnessed the equipment demonstration in June, 1998. To conduct the demonstration in the Paducah Gaseous Diffusion Plant (PGDP), the BDMS was required to meet stringent Nuclear Regulatory Commission licensing, safety and operational requirements. The Paducah demonstration was an important milestone in achieving the operational certification for the BDMS use in Russian facilities

Increased Suicide Risk among Workers following Toxic Metal Exposure at the Paducah Gaseous Diffusion Plant From 1952 to 2003: A Cohort Study

Directory of Open Access Journals (Sweden)

LW Figgs

2011-09-01

Full Text Available Background: Suicide is a problem worldwide and occupation is an important risk factor. In the last decade, 55 200 deaths in the US were attributed to occupational risk factors. Objective: To determine if toxic metal exposure was associated with suicide risk among Paducah gaseous diffusion plant (PGDP workers. Methods: We assembled a cohort of 6820 nuclear industry workers employed from 1952 to 2003. A job-specific exposure matrix (JEM was used to determine metal exposure likelihood. Uranium exposure was also assessed by urinalysis. All suicide/self-injury International Classification for Disease (ICD codes were used to identify suicides. Standardized mortality ratios (SMR, odds ratios (OR, and hazard ratios (HR were used to estimate suicide risk. Results: PGDP suicide victims typically were younger white men. Within exposure likelihood categories, several suicide SMRs were typically elevated for several metals. Only beryllium exposure likelihood was associated with an increased HR. Uranium urine concentration was associated with an elevated suicide risk after stratification by urinalysis frequency. Conclusion: Suicide risk is associated with uranium exposure.

Gaseous diffusion -- the enrichment workhorse

International Nuclear Information System (INIS)

Shoemaker, J.E. Jr.

1984-01-01

Construction of the first large-scale gaseous diffusion facility was started as part of the Manhattan Project in Oak Ridge, Tennessee, in 1943. This facility, code named ''K-25,'' began operation in January 1945 and was fully on stream by September 1945. Four additional process buildings were later added in Oak Ridge as the demand for enriched uranium escalated. New gaseous diffusion plants were constructed at Paducah, Kentucky, and Portsmouth, Ohio, during this period. The three gaseous diffusion plants were the ''workhorses'' which provided the entire enriched uranium demand for the United States during the 1950s and 1960s. As the demand for enriched uranium for military purposes decreased during the early 1960s, power to the diffusion plants was curtailed to reduce production. During the 1960s, as plans for the nuclear power industry were formulated, the role of the diffusion plants gradually changed from providing highly-enriched uranium for the military to providing low-enriched uranium for power reactors

Thermal discharges from Paducah Gaseous Diffusion Plant outfalls: Impacts on stream temperatures and fauna of Little Bayou and Big Bayou Creeks

International Nuclear Information System (INIS)

Roy, W.K.; Ryon, M.G.; Hinzman, R.L.

1996-03-01

The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the US Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7 C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances

Thermal discharges from Paducah Gaseous Diffusion Plant outfalls: Impacts on stream temperatures and fauna of Little Bayou and Big Bayou Creeks

Energy Technology Data Exchange (ETDEWEB)

Roy, W.K.; Ryon, M.G.; Hinzman, R.L. [Oak Ridge National Lab., TN (United States). Computer Science and Mathematics Div.

1996-03-01

The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the US Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7 C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances.

Thermal Discharges from Paducah Gaseous Diffusion Plant Outfalls: Impacts on Stream Temperatures and Fauna of Little Bayou and Big Bayou Creeks

International Nuclear Information System (INIS)

Roy, W.K.

1999-01-01

The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the United States Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances

Thermal Discharges from Paducah Gaseous Diffusion Plant Outfalls: Impacts on Stream Temperatures and Fauna of Little Bayou and Big Bayou Creeks

Energy Technology Data Exchange (ETDEWEB)

Roy, W.K.

1999-01-01

The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the United States Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances.

TECHNICAL EVALUATION OF TEMPORAL GROUNDWATER MONITORING VARIABILITY IN MW66 AND NEARBY WELLS, PADUCAH GASEOUS DIFFUSION PLANT

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Eddy-Dilek, C.

2012-08-28

Evaluation of disposal records, soil data, and spatial/temporal groundwater data from the Paducah Gaseous Diffusion Plant (PGDP) Solid Waste Management Unit (SWMU) 7 indicate that the peak contaminant concentrations measured in monitoring well (MW) 66 result from the influence of the regional PGDP NW Plume, and does not support the presence of significant vertical transport from local contaminant sources in SWMU 7. This updated evaluation supports the 2006 conceptualization which suggested the high and low concentrations in MW66 represent different flow conditions (i.e., local versus regional influences). Incorporation of the additional lines of evidence from data collected since 2006 provide the basis to link high contaminant concentrations in MW66 (peaks) to the regional 'Northwest Plume' and to the upgradient source, specifically, the C400 Building Area. The conceptual model was further refined to demonstrate that groundwater and the various contaminant plumes respond to complex site conditions in predictable ways. This type of conceptualization bounds the expected system behavior and supports development of environmental cleanup strategies, providing a basis to support decisions even if it is not feasible to completely characterize all of the 'complexities' present in the system. We recommend that the site carefully consider the potential impacts to groundwater and contaminant plume migration as they plan and implement onsite production operations, remediation efforts, and reconfiguration activities. For example, this conceptual model suggests that rerouting drainage water, constructing ponds or basin, reconfiguring cooling water systems, capping sites, decommissioning buildings, fixing (or not fixing) water leaks, and other similar actions will potentially have a 'direct' impact on the groundwater contaminant plumes. Our conclusion that the peak concentrations in MW66 are linked to the regional PGDP NW Plume does not imply that

Evaluation of the proposed pilot groundwater pump and treat demonstration for the Paducah Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Bodenstein, G.W.; Bonczek, R.R.; Early, T.O.; Hale, T.B.; Huff, D.D.; Nickelson, M.D.; Rightmire, C.T.

1992-11-01

This report contains the evaluation and recommendations of a Groundwater Corrective Actions Review Team. The primary goal is to evaluate the technical merit of and the need to implement a proposed groundwater pump-and-treat demonstration project for the Northwest contaminant plume at Paducah, Kentucky. A key distinction recognized by the review team is that the proposed project is intended to be a full-scale hydraulic containment of contaminants migrating from the sources of the plume, not plume remediation. The key questions incorporated into this plan are whether (1) dense, nonaqueous-phase liquids (DNAPLS) are present in the Regional Gravel Aquifer (RGA) at the source of the plume and (2) 99 Tc removal must be included as part of any groundwater treatment process. The first question cannot be answered until the contaminant sources are better defined; the second question requires further risk assessment and/or a policy decision by DOE. Technical evaluation by the review team suggests that the recommended course of action be to modify the proposed work plan to include accurate identification of the sources of contaminants and vertical distribution of contaminants within the Northwest plume before a decision is made on the preferred source-control option. If DNAPLs are not present in the RGA, removal or containment of the sources is recommended. If DNAPLs are present, then hydraulic containment will be required. Finally, the review team recognizes that it is necessary to initiate a more comprehensive analysis of sitewide remediation needs to create links between action taken for the Northwest plume and action taken for other contamination sites at PGPD

A Technical Assessment Of The Current Water Policy Boundary At U.S. Department Of Energy, Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

None

2012-01-01

In 1988, groundwater contaminated with trichloroethene (TCE) and technetium-99 (Tc-99) was identified in samples collected from residential water wells withdrawing groundwater from the Regional Gravel Aquifer (RGA) north of the Paducah Gaseous Diffusion Plant (PGDP) facility. In response, the U.S. Department of Energy (DOE) provided temporary drinking water supplies to approximately 100 potentially affected residents by initially supplying bottled water, water tanks, and water-treatment systems, and then by extending municipal water lines, all at no cost, to those persons whose wells could be affected by contaminated groundwater. The Water Policy boundary was established in 1993. In the Policy, DOE agreed to pay the reasonable monthly cost of water for homes and businesses and, in exchange, many of the land owners signed license agreements committing to cease using the groundwater via rural water wells. In 2012, DOE requested that Oak Ridge Associated Universities (ORAU), managing contractor of Oak Ridge Institute for Science and Education (ORISE), provide an independent assessment of the quality and quantity of the existing groundwater monitoring data and determine if there is sufficient information to support a modification to the boundary of the current Water Policy. As a result of the assessment, ORAU concludes that sufficient groundwater monitoring data exists to determine that a shrinkage and/or shift of the plume(s) responsible for the initial development of this policy has occurred. Specifically, there is compelling evidence that the TCE plume is undergoing shrinkage due to natural attenuation and associated degradation. The plume shrinkage (and migration) has also been augmented in local areas where large volumes of groundwater were recovered by pump-and treat remedial systems along the eastern and western boundaries of the Northwest Plume, and in other areas where pump-and-treat systems have been deployed by DOE to remove source contaminants. The

Dose Modeling Evaluations and Technical Support Document for the Authorized Limits Request for the C-746-U Landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

Boerner, A. J. [IEAVP, ORISE, Oak Ridge, TN (United States); Maldonado, D. G. [IEAVP, ORISE, Oak Ridge, TN (United States; Hansen, Tom [Ameriphysics, LLC (United States)

2012-06-01

This report contains the technical basis in support of the DOE?s derivation of Authorized Limits (ALs) for the DOE Paducah C-746-U Landfill. A complete description of the methodology, including an assessment of the input parameters, model inputs, and results is provided in this report. This report also provides initial recommendations on applying the derived soil guidelines. The ORISE-derived soil guidelines are specifically applicable to the Landfill at the end of its operational life. A suggested 'upper bound' multiple of the derived soil guidelines for individual shipments is provided.

Dose Modeling Evaluations and Technical Support Document for the Authorized Limits Request for the C-746-U Landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

Boerner, A. J.; Maldonado, D. G.; Hansen, Tom

2012-01-01

This report contains the technical basis in support of the DOE's derivation of Authorized Limits (ALs) for the DOE Paducah C-746-U Landfill. A complete description of the methodology, including an assessment of the input parameters, model inputs, and results is provided in this report. This report also provides initial recommendations on applying the derived soil guidelines. The ORISE-derived soil guidelines are specifically applicable to the Landfill at the end of its operational life. A suggested 'upper bound' multiple of the derived soil guidelines for individual shipments is provided

Evaluation of the proposed pilot groundwater pump and treat demonstration for the Paducah Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Bodenstein, G.W.; Bonczek, R.R.; Early, T.O.; Hale, T.B.; Huff, D.D.; Nickelson, M.D.; Rightmire, C.T.

1992-11-01

This report contains the evaluation and recommendations of a Groundwater Corrective Actions Review Team. The primary goal is to evaluate the technical merit of and the need to implement a proposed groundwater pump-and-treat demonstration project for the Northwest contaminant plume at Paducah, Kentucky. A key distinction recognized by the review team is that the proposed project is intended to be a full-scale hydraulic containment of contaminants migrating from the sources of the plume, not plume remediation. The key questions incorporated into this plan are whether (1) dense, nonaqueous-phase liquids (DNAPLS) are present in the Regional Gravel Aquifer (RGA) at the source of the plume and (2) [sup 99]Tc removal must be included as part of any groundwater treatment process. The first question cannot be answered until the contaminant sources are better defined; the second question requires further risk assessment and/or a policy decision by DOE. Technical evaluation by the review team suggests that the recommended course of action be to modify the proposed work plan to include accurate identification of the sources of contaminants and vertical distribution of contaminants within the Northwest plume before a decision is made on the preferred source-control option. If DNAPLs are not present in the RGA, removal or containment of the sources is recommended. If DNAPLs are present, then hydraulic containment will be required. Finally, the review team recognizes that it is necessary to initiate a more comprehensive analysis of sitewide remediation needs to create links between action taken for the Northwest plume and action taken for other contamination sites at PGPD.

76 FR 5147 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2011-01-28

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

77 FR 59598 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-09-28

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

75 FR 54600 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-09-08

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

75 FR 66074 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-10-27

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

75 FR 24686 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-05-05

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

76 FR 80355 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2011-12-23

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... make recommendations to DOE-EM and site management in the areas of environmental restoration, waste...

75 FR 9404 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-03-02

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

77 FR 43583 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-07-25

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

75 FR 61711 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-10-06

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

75 FR 82002 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2010-12-29

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

76 FR 61350 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2011-10-04

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... make recommendations to DOE-EM and site management in the areas of environmental restoration, waste...

77 FR 2282 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-01-17

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... the Environmental Management Site-Specific Advisory Board, Paducah. This notice announces the... Management Officer. [FR Doc. 2012-831 Filed 1-12-12; 4:15 pm] BILLING CODE 6405-01-P ...

76 FR 48148 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2011-08-08

... DEPARTMENT OF ENERGY Environmental Management Site-Specific Advisory Board, Paducah AGENCY... Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act... recommendations to DOE-EM and site management in the areas of environmental restoration, waste management and...

Control of technetium at the Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Saraceno, A.J.

1981-01-01

Technetium-99 entered the gaseous diffusion complex as a volatile impurity in recycled uranium that was fed to the Paducah Gaseous Diffusion Plant. Subsequently, it entered the Oak Ridge and Portsmouth cascades as an impurity in Paducah product feed. Most of the technetium was adsorbed on cascade equipment in increasingly high concentrations as it moved up the cascade. Since the low energy beta radiation produced by technetium cannot penetrate cascade equipment, it presents no significant hazard to workers as long as it remains inside of equipment. However, when equipment that contains high concentrations of technetium is opened for maintenance or change-out, precautions are taken to ensure worker safety. Traps containing activated alumina are used at the plant vent streams to limit radioactive emissions as far as possible. Annual vent stream emissions have been well below DOE limits. To allow continued compliance, other potential trapping agents have been tested. Several that limit emissions more effectively than activated alumina have been found. Other traps containing magnesium fluoride are used in the upper cascade to reduce the technetium concentration. Waste solutions from decontamination can also contain technetium. These solutions must either be stored for controlled discharge or treated to remove the technetium. To allow the latter, an ion exchange facility is being installed for operation by the end of FY-1982. Liquid discharges at Portsmouth have usually been less than 5% of the DOE imposed limits

Applicable or relevant and appropriate requirements (ARARs) for remedial actions at the Paducah Gaseous Diffusion Plant: A compendium of environmental laws and guidance

International Nuclear Information System (INIS)

Etnier, E.L.; Eaton, L.A.

1992-03-01

Section 121 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 specifies that remedial actions for cleanup of hazardous substances found at sites placed on the National Priorities List (NPL) by the US Environmental Protection Agency (EPA) must comply with applicable or relevant and appropriate requirements (ARARs) or standards under federal and state environmental laws. To date, the US Department of Energy (DOE) Paducah Gaseous Diffusion Plant (PGDP) has not been on the NPL. Although DOE and EPA have entered into an Administrative Consent Order (ACO), the prime regulatory authority for cleanup at PGDP will be the Resource Conservation and Recovery Act (RCRA). This report supplies a preliminary list of available federal and state ARARs that might be considered for remedial response at PGDP in the event that the plant becomes included on the NPL or the ACO is modified to include CERCLA cleanup. A description of the terms ''applicable'' and ''relevant and appropriate'' is provided, as well as definitions of chemical-, location-, and action-specific ARARS. ARARs promulgated by the federal government and by the state of Kentucky are listed in tables. In addition, the major provisions of RCRA, the Safe Drinking Water Act, the Clean Water Act, the Clean Air Act, and other acts, as they apply to hazardous and radioactive waste cleanup, are discussed

Portsmouth Gaseous Diffusion Plant Annual Site Environmental Report summary for 1993

International Nuclear Information System (INIS)

1994-11-01

This report contains summaries of the environmental programs at Paducah Gaseous Diffusion Plant, environmental monitoring and the results, and the impact of operations on the environment and the public for 1993. The environmental monitoring program at Paducah includes effluent monitoring and environmental surveillance. Effluent monitoring is measurement of releases as they occur. Contaminants are released through either airborne emissions or liquids discharged from the plant. These releases occur as part of normal site operations, such as cooling water discharged from the uranium enrichment cascade operations or airborne releases from ventilation systems. In the event of system failure, this monitoring provides timely warning so that corrective action can be taken before releases reach an unsafe level. Environmental surveillance tracks the dispersion of materials into the environment after they have been released. This involves the collection of samples from various media, such as water, soil, vegetation, and food crops, and the analysis of these samples for certain radionuclides, chemicals, and metals

Application of the electromagnetic borehole flowmeter and evaluation of previous pumping tests at Paducah Gaseous Diffusion Plant. Final report, June 15, 1992--August 31, 1992

Energy Technology Data Exchange (ETDEWEB)

Young, S.C.; Julian, S.C.; Neton, M.J.

1993-01-01

Multi-well pumping tests have been concluded at wells MW79, MW108, and PW1 at the Paducah Gaseous Diffusion Plant (PGDP) to determine the hydraulic properties of the Regional Gravel Aquifer (RGA). Soil cores suggest that the RGA consists of a thin sandy facies (2 to 6 feet) at the top of a thicker (> 10 feet) gravelly facies. Previous analyses have not considered any permeability contrast between the two facies. To assess the accuracy of this assumption, TVA personnel conducted borehole flowmeter tests at wells MW108 and PW1. Well MW79 could not be tested. The high K sand unit is probably 10 times more permeable than comparable zone in the gravelly portion of the RGA. Previous analyses of the three multi-well aquifer tests do not use the same conceptual aquifer model. Data analysis for one pumping test assumed that leakance was significant. Data analysis for another pumping test assumed that a geologic boundary was significant. By collectively analyzing all three tests with the borehole flowmeter results, the inconsistency among the three pumping tests can be explained. Disparity exists because each pumping test had a different placement of observation wells relative to the high K zone delineating by flowmeter testing.

Gamma radiological surveys of the Oak Ridge Reservation, Paducah Gaseous Diffusion Plant, and Portsmouth Gaseous Diffusion Plant, 1990-1993, and overview of data processing and analysis by the Environmental Restoration Remote Sensing Program, Fiscal Year 1995

International Nuclear Information System (INIS)

Smyre, J.L.; Moll, B.W.; King, A.L.

1996-06-01

Three gamma radiological surveys have been conducted under auspices of the ER Remote Sensing Program: (1) Oak Ridge Reservation (ORR) (1992), (2) Clinch River (1992), and (3) Portsmouth Gaseous Diffusion Plant (PORTS) (1993). In addition, the Remote Sensing Program has acquired the results of earlier surveys at Paducah Gaseous Diffusion Plant (PGDP) (1990) and PORTS (1990). These radiological surveys provide data for characterization and long-term monitoring of U.S. Department of Energy (DOE) contamination areas since many of the radioactive materials processed or handled on the ORR, PGDP, and PORTS are direct gamma radiation emitters or have gamma emitting daughter radionuclides. High resolution airborne gamma radiation surveys require a helicopter outfitted with one or two detector pods, a computer-based data acquisition system, and an accurate navigational positioning system for relating collected data to ground location. Sensors measure the ground-level gamma energy spectrum in the 38 to 3,026 KeV range. Analysis can provide gamma emission strength in counts per second for either gross or total man-made gamma emissions. Gross count gamma radiation includes natural background radiation from terrestrial sources (radionuclides present in small amounts in the earth's soil and bedrock), from radon gas, and from cosmic rays from outer space as well as radiation from man-made radionuclides. Man-made count gamma data include only the portion of the gross count that can be directly attributed to gamma rays from man-made radionuclides. Interpretation of the gamma energy spectra can make possible the determination of which specific radioisotopes contribute to the observed man-made gamma radiation, either as direct or as indirect (i.e., daughter) gamma energy from specific radionuclides (e.g., cesium-137, cobalt-60, uranium-238)

Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

1996-07-01

The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact

Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-07-01

The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact.

Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant. [Transport of drift-derived chromium in terrestrial ecosystems

Energy Technology Data Exchange (ETDEWEB)

Taylor, F.G.; Hanna, S.R.; Parr, P.D.

1979-01-01

The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified at the Department of Energy's uranium enrichment facility at Paducah, Kentucky. Chromium concentrations in plant materials (fescue grass) decreased with increasing distance from the cooing tower, ranging from 251 +- 19 ppM at 15 meters to 0.52 +- 0.07 ppM at 1500 meters. The site of drift contamination, size characteristics, and elemental content of drift particles were determined using a scanning electron microscope with energy dispersive x-ray analysis capabilities. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. A laboratory study simulating throughfall from 1 to 6 inches of rain suggested that there are more exchange sites associated with litter than live foliage. Leachate from each one inch throughfall simulant removed 3% of the drift mass from litter compared to 7 to 9% from live foliage. Results suggest that differences in retention are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil--water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Samples from two depths following rainstorms revealed the absence of vertical or horizontal movement with maximum concentrations of 0.13 ppb at 50 meters from the tower. Preliminary model estimates of drift deposition are compared to depositionmeasurements. Isopleths of the predicted deposition are useful to identify areas of maximum drift transport in the environs of the gaseous diffusion plant.

Evaluation of the proposed pilot groundwater pump and treat demonstration for the Paducah Gaseous Diffusion Plant. Environmental Restoration Program

Energy Technology Data Exchange (ETDEWEB)

Bodenstein, G.W.; Bonczek, R.R.; Early, T.O.; Hale, T.B.; Huff, D.D.; Nickelson, M.D.; Rightmire, C.T.

1992-11-01

This report contains the evaluation and recommendations of a Groundwater Corrective Actions Review Team. The primary goal is to evaluate the technical merit of and the need to implement a proposed groundwater pump-and-treat demonstration project for the Northwest contaminant plume at Paducah, Kentucky. A key distinction recognized by the review team is that the proposed project is intended to be a full-scale hydraulic containment of contaminants migrating from the sources of the plume, not plume remediation. The key questions incorporated into this plan are whether (1) dense, nonaqueous-phase liquids (DNAPLS) are present in the Regional Gravel Aquifer (RGA) at the source of the plume and (2) {sup 99}Tc removal must be included as part of any groundwater treatment process. The first question cannot be answered until the contaminant sources are better defined; the second question requires further risk assessment and/or a policy decision by DOE. Technical evaluation by the review team suggests that the recommended course of action be to modify the proposed work plan to include accurate identification of the sources of contaminants and vertical distribution of contaminants within the Northwest plume before a decision is made on the preferred source-control option. If DNAPLs are not present in the RGA, removal or containment of the sources is recommended. If DNAPLs are present, then hydraulic containment will be required. Finally, the review team recognizes that it is necessary to initiate a more comprehensive analysis of sitewide remediation needs to create links between action taken for the Northwest plume and action taken for other contamination sites at PGPD.

An introduction to technetium in the gaseous diffusion cascades

International Nuclear Information System (INIS)

Simmons, D.W.

1996-09-01

The radioisotope technetium-99 ( 99 Tc) was introduced into the gaseous diffusion plants (GDP) as a contaminant in uranium that had been reprocessed from spent nuclear reactor fuel. 99 Tc is a product of the nuclear fission of uranium-235 ( 235 U). The significantly higher emitted radioactivity of 99 Tc generates concern in the enrichment complex and warrants increased attention (1) to the control of all site emissions, (2) to worker exposures and contamination control when process equipment requires disassembly and decontamination, and (3) to product purity when the enriched uranium hexafluoride (UF 6 ) product is marketed to the private sector. A total of 101,268 metric tons of RU (∼96% of the total) was fed at the Paducah Gaseous Diffusion Plant (PGDP) between FY1953 and FY1976. An additional 5600 metric tons of RU from the government reactors were fed at the Oak Ridge Gaseous Diffusion Plant (ORGDP), plus an approximate 500 tons of foreign reactor returns. Only a small amount of RU was fed directly at the Portsmouth Gaseous Diffusion Plant (PORTS). The slightly enriched PGDP product was then fed to either the ORGDP or PORTS cascades for final enrichment. Bailey estimated in 1988 that of the 606 kg of Tc received at PGDP from RU, 121 kg was subsequently re-fed to ORGDP and 85 kg re-fed to PORTS

Depleted uranium hexafluoride management program : data compilation for the Paducah site

International Nuclear Information System (INIS)

Hartmann, H.

2001-01-01

This report is a compilation of data and analyses for the Paducah site, near Paducah, Kentucky. The data were collected and the analyses were done in support of the U.S. Department of Energy (DOE) 1999 Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride (DOE/EIS-0269). The report describes the affected environment at the Paducah site and summarizes potential environmental impacts that could result from conducting the following depleted uranium hexafluoride (UF 6 ) activities at the site: continued cylinder storage, preparation of cylinders for shipment, conversion, and long-term storage. DOE's preferred alternative is to begin converting the depleted UF 6 inventory as soon as possible to either uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible

Lung Cancer Mortality among Uranium Gaseous Diffusion Plant Workers: A Cohort Study 1952–2004

Directory of Open Access Journals (Sweden)

LW Figgs

2013-07-01

Full Text Available Background: 9%–15% of all lung cancers are attributable to occupational exposures. Reports are disparate regarding elevated lung cancer mortality risk among workers employed at uranium gaseous diffusion plants. Objective: To investigate whether external radiation exposure is associated with lung cancer mortality risk among uranium gaseous diffusion workers. Methods: A cohort of 6820 nuclear industry workers employed from 1952 to 2003 at the Paducah uranium gaseous diffusion plant (PGDP was assembled. A job-specific exposure matrix (JEM was used to determine likely toxic metal exposure categories. In addition, radiation film badge dosimeters were used to monitor cumulative external ionizing radiation exposure. International Classification for Disease (ICD codes 9 and 10 were used to identify 147 lung cancer deaths. Logistic and proportional hazards regression were used to estimate lung cancer mortality risk. Results: Lung cancer mortality risk was elevated among workers who experienced external radiation >3.5 mrem and employment duration >12 years. Conclusion: Employees of uranium gaseous diffusion plants carry a higher risk of lung cancer mortality; the mortality is associated with increased radiation exposure and duration of employment.

APPLICATION OF THE LASAGNA(trademark) SOIL REMEDIATION TECHNOLOGY AT THE DOE PADUCAH GASEOUS DIFFUSION PLANT

International Nuclear Information System (INIS)

Swift, Barry D.; Tarantino, Joseph J. P. E.

2003-01-01

The Paducah Gaseous Diffusion Plant (PGDP), owned by the Department of Energy (DOE), has been enriching uranium since the early 1950s. The enrichment process involves electrical and mechanical components that require periodic cleaning. The primary cleaning agent was trichloroethene (TCE) until the late 1980s. Historical documentation indicates that a mixture of TCE and dry ice were used at PGDP for testing the integrity of steel cylinders, which stored depleted uranium. TCE and dry ice were contained in a below-ground pit and used during the integrity testing. TCE seeped from the pit and contaminated the surrounding soil. The Lasagna(trademark) technology was identified in the Record of Decision (ROD) as the selected alternative for remediation of the cylinder testing site. A public-private consortium formed in 1992 (including DOE, the U.S. Environmental Protection Agency, and the Kentucky Department for Environmental Protection, Monsanto, DuPont, and General Electric) developed the Lasagna(trademark) technology. This innovative technology employs electrokinetics to remediate soil contaminated with organics and is especially suited to sites with low permeability soils. This technology uses direct current to move water through the soil faster and more uniformly than hydraulic methods. Electrokinetics moves contaminants in soil pore water through treatment zones comprised of iron filings, where the contaminants are decomposed to basic chemical compounds such as ethane. After three years of development in the laboratory, the consortium field tested the Lasagna(trademark) process in several phases. CDM installed and operated Phase I, the trial installation and field test of a 150-square-foot area selected for a 120-day run in 1995. Approximately 98 percent of the TCE was removed. CDM then installed and operated the next phase (IIa), a year-long test on a 600-square-foot site. Completed in July 1997, this test removed 75 percent of the total volume of TCE down to a

Independent Technical Review of the C-400 Interim Remedial Project Phase I Results, Paducah, Kentucky

International Nuclear Information System (INIS)

Looney, B.; Rossabi, J.; Stewart, L.; Richards, W.

2010-01-01

The groundwater and soil in the vicinity of the C-400 Building at the Paducah Gaseous Diffusion Plant (PGDP), is contaminated with substantial quantities of industrial solvents, primarily trichoroethene (TCE). This solvent 'source' is recognized as a significant challenge and an important remediation target in the overall environmental cleanup strategy for PGDP. Thus, the cleanup of the C-400 TCE Source is a principal focus for the Department of Energy (DOE) and its contractors, and for PGDP regulators and stakeholders. Using a formal investigation, feasibility study and decision process, Electrical Resistance Heating (ERH) was selected for the treatment of the soil and groundwater in the vicinity of C-400. ERH was selected as an interim action to remove 'a significant portion of the contaminant mass of TCE at the C-400 Cleaning Building area through treatment' with the longer term goal of reducing 'the period the TCE concentration in groundwater remains above its Maximum Contaminant Level (MCL).' ERH is a thermal treatment that enhances the removal of TCE and related solvents from soil and groundwater. The heterogeneous conditions at PGDP, particularly the high permeability regional gravel aquifer (RGA), are challenging to ERH. Thus, a phased approach is being followed to implement this relatively expensive and complex remediation technology. Conceptually, the phased approach encourages safety and efficiency by providing a 'lessons learned' process and allowing appropriate adjustments to be identified and implemented prior to follow-on phase(s) of treatment. More specifically, early deployment targeted portions of the challenging RGA treatment zone with relatively little contamination reducing the risk of adverse collateral impacts from underperformance in terms of heating and capture. Because of the importance and scope of the C-400 TCE source remediation activities, DOE chartered an Independent Technical Review (ITR) in 2007 to assess the C-400 ERH plans prior

INDEPENDENT TECHNICAL REVIEW OF THE C-400 INTERIM REMEDIAL PROJECT PHASE I RESULTS, PADUCAH, KENTUCKY

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Rossabi, J.; Stewart,L.; Richards, W.

2010-10-29

The groundwater and soil in the vicinity of the C-400 Building at the Paducah Gaseous Diffusion Plant (PGDP), is contaminated with substantial quantities of industrial solvents, primarily trichoroethene (TCE). This solvent 'source' is recognized as a significant challenge and an important remediation target in the overall environmental cleanup strategy for PGDP. Thus, the cleanup of the C-400 TCE Source is a principal focus for the Department of Energy (DOE) and its contractors, and for PGDP regulators and stakeholders. Using a formal investigation, feasibility study and decision process, Electrical Resistance Heating (ERH) was selected for the treatment of the soil and groundwater in the vicinity of C-400. ERH was selected as an interim action to remove 'a significant portion of the contaminant mass of TCE at the C-400 Cleaning Building area through treatment' with the longer term goal of reducing 'the period the TCE concentration in groundwater remains above its Maximum Contaminant Level (MCL).' ERH is a thermal treatment that enhances the removal of TCE and related solvents from soil and groundwater. The heterogeneous conditions at PGDP, particularly the high permeability regional gravel aquifer (RGA), are challenging to ERH. Thus, a phased approach is being followed to implement this relatively expensive and complex remediation technology. Conceptually, the phased approach encourages safety and efficiency by providing a 'lessons learned' process and allowing appropriate adjustments to be identified and implemented prior to follow-on phase(s) of treatment. More specifically, early deployment targeted portions of the challenging RGA treatment zone with relatively little contamination reducing the risk of adverse collateral impacts from underperformance in terms of heating and capture. Because of the importance and scope of the C-400 TCE source remediation activities, DOE chartered an Independent Technical Review (ITR) in

ENZYME ACTIVITY PROBE AND GEOCHEMICAL ASSESSMENT FOR POTENTIAL AEROBIC COMETABOLISM OF TRICHLOROETHENE IN GROUNDWATER OF THE NORTHWEST PLUME, PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

International Nuclear Information System (INIS)

Looney, B; M. Hope Lee, M; S. K. Hampson, S

2008-01-01

The overarching objective of the Paducah Gaseous Diffusion Plant (PGDP) enzyme activity probe (EAP) effort is to determine if aerobic cometabolism is contributing to the attenuation of trichloroethene (TCE) and other chlorinated solvents in the contaminated groundwater beneath PGDP. The site-specific objective for the EAP assessment is to identify if key metabolic pathways are present and expressed in the microbial community--namely the pathways that are responsible for degradation of methane and aromatic (e.g. toluene, benzene, phenol) substrates. The enzymes produced to degrade methane and aromatic compounds also break down TCE through a process known as cometabolism. EAPs directly measure if methane and/or aromatic enzyme production pathways are operating and, for the aromatic pathways, provide an estimate of the number of active organisms in the sampled groundwater. This study in the groundwater plumes at PGDP is a major part of a larger scientific effort being conducted by Interstate Technology and Regulatory Council (ITRC), U.S. Department of Energy (DOE) Office of Environmental Management (EM), Savannah River National Laboratory (SRNL), and North Wind Inc. in which EAPs are being applied to contaminated groundwater from diverse hydrogeologic and plume settings throughout the U.S. to help standardize their application as well as their interpretation. While EAP data provide key information to support the site specific objective for PGDP, several additional lines of evidence are being evaluated to increase confidence in the determination of the occurrence of biodegradation and the rate and sustainability of aerobic cometabolism. These complementary efforts include: (1) Examination of plume flowpaths and comparison of TCE behavior to 'conservative' tracers in the plume (e.g., 99 Tc); (2) Evaluation of geochemical conditions throughout the plume; and (3) Evaluation of stable isotopes in the contaminants and their daughter products throughout the plume. If the

Issues and recommendations related to replacement of CFC-114 at the uranium enrichment gaseous diffusion plant

International Nuclear Information System (INIS)

Anderson, B.L.; Banaghan, E.

1993-01-01

The operating uranium enrichment gaseous diffusion plants (GDPs) in Portsmouth, Ohio and Paducah, Kentucky, which are operated for the United States Department for Energy by Martin Marietta Energy Systems (MMES), currently use a chlorofluorocarbon (CFC-114) as the primary process stream coolant. Due to recent legislation embodied in the Clean Air Act, the production of this and other related chlorofluorocarbons (CFCS) are to be phased out with no production occurring after 1995. Since the plants lose approximately 500,000 pounds per year of this process stream coolant through various leaks, the GDPs are faced with the challenge of identifying a replacement coolant that will allow continued operation of the plants. MMES formed the CFC Task Team to identify and solve the various problems associated with identifying and implementing a replacement coolant. This report includes a review of the work performed by the CFC Task Team, and recommendations that were formulated based on this review and upon original work. The topics covered include; identifying a replacement coolant, coolant leak detection and repair efforts, coolant safety concerns, coolant level sensors, regulatory issues, and an analytical decision analysis

Gaseous diffusion plant transition from DOE to external regulation

International Nuclear Information System (INIS)

Dann, R.K.; Crites, T.R.; Rahm-Crites, L.K.

1997-01-01

After many years of operation as government-owned/contractor-operated facilities, large portions of the gaseous diffusion plants (GDPs) at Portsmouth, Ohio, and Paducah, Kentucky, were leased to the United States Enrichment Corporation (USEC). These facilities are now certified by the U.S. Nuclear Regulatory Commission (NRC) and subject to oversight by the Occupational Safety and Health Administration (OSHA). The transition from DOE to NRC regulation was more difficult than expected. The original commitment was to achieve NRC certification in October 1995; however, considerably more time was required and transition-related costs escalated. The Oak Ridge Operations Office originally estimated the cost of transition at $60 million; $240 million has been spent to date. The DOE's experience in transitioning the GDPs to USEC operation with NRC oversight provides valuable lessons (both positive and negative) that could be applied to future transitions

Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

International Nuclear Information System (INIS)

Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C.

1995-01-01

In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation

Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

Energy Technology Data Exchange (ETDEWEB)

Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C. [Oak Ridge National Lab., TN (United States). Technical Programs and Services; Brock, W.R.; Denton, D.R. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States)

1995-12-31

In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation.

Final Report: Seismic Hazard Assessment at the PGDP

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhinmeng [KY Geological Survey, Univ of KY

2007-06-01

Selecting a level of seismic hazard at the Paducah Gaseous Diffusion Plant for policy considerations and engineering design is not an easy task because it not only depends on seismic hazard, but also on seismic risk and other related environmental, social, and economic issues. Seismic hazard is the main focus. There is no question that there are seismic hazards at the Paducah Gaseous Diffusion Plant because of its proximity to several known seismic zones, particularly the New Madrid Seismic Zone. The issues in estimating seismic hazard are (1) the methods being used and (2) difficulty in characterizing the uncertainties of seismic sources, earthquake occurrence frequencies, and ground-motion attenuation relationships. This report summarizes how input data were derived, which methodologies were used, and what the hazard estimates at the Paducah Gaseous Diffusion Plant are.

78 FR 73519 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-12-06

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 45518 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-07-29

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 38969 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-06-28

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 54460 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-09-04

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 25064 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-04-29

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 78952 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-12-27

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 32640 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-05-31

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

77 FR 4799 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-01-31

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 7767 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-02-04

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

77 FR 31837 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2012-05-30

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. No. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 16260 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-03-14

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. No. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

78 FR 26635 - Environmental Management Site-Specific Advisory Board, Paducah

Science.gov (United States)

2013-05-07

...On April 29, 2013, the Department of Energy (DOE) published a notice of open meeting announcing a meeting on May 16, 2013 of the Environmental Management Site-Specific Advisory Board, Paducah (78 FR 25064). This document makes a correction to that notice.

REVIEW REPORT: BUILDING C-400 THERMAL TREATMENT 90 PERCENT REMEDIAL DESIGN REPORT AND SITE INVESTIGATION, PGDP, PADUCAH, KENTUCKY

International Nuclear Information System (INIS)

Looney, B; Jed Costanza, J; Eva Davis, E; Joe Rossabi, J; Lloyd Stewart, L; Hans Stroo, H

2007-01-01

On 9 April 2007, the U.S. Department of Energy (DOE) Headquarters, Office of Soil and Groundwater Remediation (EM-22) initiated an Independent Technical Review (ITR) of the 90% Remedial Design Report (RDR) and Site Investigation (RDSI) for thermal treatment of trichloroethylene (TCE) in the soil and groundwater in the vicinity of Building C-400 at the Paducah Gaseous Diffusion Plant (PGDP). The general ITR goals were to assess the technical adequacy of the 90% RDSI and provide recommendations sufficient for DOE to determine if modifications are warranted pertaining to the design, schedule, or cost of implementing the proposed design. The ultimate goal of the effort was to assist the DOE Paducah/Portsmouth Project Office (PPPO) and their contractor team in ''removing'' the TCE source zone located near the C-400 Building. This report provides the ITR findings and recommendations and supporting evaluations as needed to facilitate use of the recommendations. The ITR team supports the remedial action objective (RAO) at C-400 to reduce the TCE source area via subsurface Electrical Resistance Heating (ERH). Further, the ITR team commends PPPO, their contractor team, regulators, and stakeholders for the significant efforts taken in preparing the 90% RDR. To maximize TCE removal at the target source area, several themes emerge from the review which the ITR team believes should be considered and addressed before implementing the thermal treatment. These themes include the need for: (1) Accurate and site-specific models as the basis to verify the ERH design for full-scale implementation for this challenging hydrogeologic setting; (2) Flexible project implementation and operation to allow the project team to respond to observations and data collected during construction and operation; (3) Defensible performance metrics and monitoring, appropriate for ERH, to ensure sufficient and efficient clean-up; and (4) Comprehensive (creative and diverse) contingencies to address the

78 FR 63172 - Environmental Management Site-Specific Advisory Board, Paducah; Meeting

Science.gov (United States)

2013-10-23

...This notice announces a meeting of the Environmental Management Site-Specific Advisory Board (EM SSAB), Paducah. The Federal Advisory Committee Act (Pub. L. 92-463, 86 Stat. 770) requires that public notice of this meeting be announced in the Federal Register.

Review of microfluidic cell culture devices for the control of gaseous microenvironments in vitro

Science.gov (United States)

Wu, H.-M.; Lee, T.-A.; Ko, P.-L.; Chiang, H.-J.; Peng, C.-C.; Tung, Y.-C.

2018-04-01

Gaseous microenvironments play important roles in various biological activities in vivo. However, it is challenging to precisely control gaseous microenvironments in vitro for cell culture due to the high diffusivity nature of gases. In recent years, microfluidics has paved the way for the development of new types of cell culture devices capable of manipulating cellular microenvironments, and provides a powerful tool for in vitro cell studies. This paper reviews recent developments of microfluidic cell culture devices for the control of gaseous microenvironments, and discusses the advantages and limitations of current devices. We conclude with suggestions for the future development of microfluidic cell culture devices for the control of gaseous microenvironments.

Paducah Site annual environmental report summary for 1995

International Nuclear Information System (INIS)

Belcher, G.

1997-01-01

This report contains summaries of the environmental programs at the Paducah Site, as well as the impacts of its operations on the environment and the public for 1995. The results of environmental monitoring are presented. The goal is to keep emissions as low as possible, enhance the strict safety controls that are in place and use state-of-the-art technology to complete environmental remediation projects in the most cost-effective and efficient manner possible

Safety analysis report on the ''Paducah Tiger'' protective overpack for 10-ton cylinders of uranium hexafluoride. Supplement 1

International Nuclear Information System (INIS)

Stitt, D.H.

1977-01-01

This supplement details design changes made to the ''Paducah Tiger'' since the issue date of the SAR, June 16, 1976. A 3 / 8 -inch thick, 304L stainless steel plate has been added on the valve end of existing and future overpacks to provide increased puncture resistance and the overpack cavity has been modified to preclude incorrect loading of the type 48X cylinder. Temperature profiles of the ''Paducah Tiger'' during the 30-minute fire test are included

Task 16 -- Sampling and analysis at the Vortec vitrification facility in Paducah, Kentucky. Semi-annual report, April 1--September 30, 1997

International Nuclear Information System (INIS)

Laudal, D.L.; Lilemoen, C.M.; Hurley, J.P.; Ness, S.R.; Stepan, D.J.; Thompson, J.S.

1997-05-01

The Vortec Cyclone Melting System (CMS reg-sign) facility, to be located at the US Department of Energy (DOE) Paducah Gaseous Diffusion Plant, is designed to treat soil contaminated with low levels of heavy metals and radioactive elements, as well as organic waste. To assure that costs of sampling and analysis are contained, Vortec and the DOE Federal Energy Technology Center (FETC) have decided that initially the primary focus of the sampling activities will be on meeting permitting requirements of the state of Kentucky. Therefore, sampling will be limited to the feedstock entering the system, and the glass, flue gas, and water leaving the system. The authors provide suggestions for optional sampling points and procedures in case there is later interest in operations or mass balance data. The permits do not require speciation of the materials in the effluents, only opacity, total radioactivity, total particulate, and total HCl emissions for the gaseous emissions and total radioactivity in the water and solid products. In case future testing to support operations or mass balances is required, the authors include in this document additional information on the analyses of some species of interest. They include heavy metals (RCRA [Resource Conservation and Recovery Act] and Cu and Ni), radionuclides (Th 230 , U 235 , Tc 99 , Cs 137 , and Pu 239 ), and dioxins/furans

Draft Environmental Impact Statement for Construction and Operation of a Depleted Uranium Hexafluoride Conversion Facility at the Paducah, Kentucky, Site

International Nuclear Information System (INIS)

2003-01-01

This document is a site-specific environmental impact statement (EIS) for construction and operation of a proposed depleted uranium hexafluoride (DUF 6 ) conversion facility at the U.S. Department of Energy (DOE) Paducah site in northwestern Kentucky (Figure S-1). The proposed facility would convert the DUF 6 stored at Paducah to a more stable chemical form suitable for use or disposal. In a Notice of Intent (NOI) published in the ''Federal Register'' (FR) on September 18, 2001 (''Federal Register'', Volume 66, page 48123 [66 FR 48123]), DOE announced its intention to prepare a single EIS for a proposal to construct, operate, maintain, and decontaminate and decommission two DUF 6 conversion facilities at Portsmouth, Ohio, and Paducah, Kentucky, in accordance with the National Environmental Policy Act of 1969 (NEPA) (''United States Code'', Title 42, Section 4321 et seq. [42 USC 4321 et seq.]) and DOE's NEPA implementing procedures (''Code of Federal Regulations'', Title 10, Part 1021 [10 CFR Part 1021]). Subsequent to award of a contract to Uranium Disposition Services, LLC (hereafter referred to as UDS), Oak Ridge, Tennessee, on August 29, 2002, for design, construction, and operation of DUF 6 conversion facilities at Portsmouth and Paducah, DOE reevaluated its approach to the NEPA process and decided to prepare separate site-specific EISs. This change was announced in a ''Federal Register'' Notice of Change in NEPA Compliance Approach published on April 28, 2003 (68 FR 22368); the Notice is included as Attachment B to Appendix C of this EIS. This EIS addresses the potential environmental impacts from the construction, operation, maintenance, and decontamination and decommissioning (DandD) of the proposed conversion facility at three alternative locations within the Paducah site; from the transportation of depleted uranium conversion products to a disposal facility; and from the transportation, sale, use, or disposal of the fluoride-containing conversion products

Sampling and Analysis at the Vortec Vitrification Facility in Paducah, Kentucky. Semiannual report, November 1, 1996--March 31, 1997

International Nuclear Information System (INIS)

Laudal, Dennis L.; Lillemoen, Carolyn M.; Hurley, John P.; Ness, Sumitra R.; Stepan, Daniel J.; Thompson, Jeffrey S.

1997-01-01

The Vortec Cyclone Melting System (CMS) facility; to be located at the U.S. Department of Energy (DOE) Paducah Gaseous Diffusion Plant, is designed to treat soil contaminated with low levels of heavy metals and radioactive elements, as well as organic waste. The primary components of Vortec's CMS are a counter rotating vortex (CRV) reactor and cyclone melter. In the CMS process, granular glass forming ingredients and other feedstocks are introduced into the CRV reactor where the intense CRV mixing allows the mixture to achieve a stable reaction and rapid heating of the feedstock materials. Organic contaminants in the feedstock are effectively oxidized, and the inert inorganic solids are melted. The University of North Dakota Energy ampersand Environmental Research Center (EERC) has been contacted to help in the development of sampling plans and to conduct the sampling at the facility. This document is written in a format that assumes that the EERC will perform the sampling activities and be in charge of sample chain of custody, but that another laboratory will perform required sample analyses

COMBINED GEOPHYSICAL INVESTIGATION TECHNIQUES TO IDENTIFY BURIED WASTE IN AN UNCONTROLLED LANDFILL AT THE PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

International Nuclear Information System (INIS)

Miller, Peter T.; Starmer, R. John

2003-01-01

The primary objective of the investigation was to confirm the presence and determine the location of a cache of 30 to 60 buried 55-gallon drums that were allegedly dumped along the course of the pre-existing, northsouth diversion ditch (NSDD) adjacent to permitted landfills at the Paducah Gaseous Diffusion Plant, Kentucky. The ditch had been rerouted and was being filled and re-graded at the time of the alleged dumping. Historic information and interviews with individuals associated with alleged dumping activities indicated that the drums were dumped prior to the addition of other fill materials. In addition, materials alleged to have been dumped in the ditch, such as buried roofing materials, roof flashing, metal pins, tar substances, fly ash, and concrete rubble complicated data interpretation. Some clean fill materials have been placed over the site and graded. This is an environment that is extremely complicated in terms of past waste dumping activities, construction practices and miscellaneous landfill operations. The combination of site knowledge gained from interviews and research of existing site maps, variable frequency EM data, classical total magnetic field data and optimized GPR lead to success where a simpler less focused approach by other investigators using EM-31 and EM-61 electromagnetic methods and unfocused ground penetrating radar (GPR)did not produce results and defined no real anomalies. A variable frequency electromagnetic conductivity unit was used to collect the EM data at 3,030 Hz, 5,070 Hz, 8,430 Hz, and 14,010 Hz. Both in-phase and quadrature components were recorded at each station point. These results provided depth estimates for targets and some information on the subsurface conditions. A standard magnetometer was used to conduct the magnetic survey that showed the locations and extent of buried metal, the approximate volume of ferrous metal present within a particular area, and allowed estimation of approximate target depths. The GPR

COMBINED GEOPHYSICAL INVESTIGATION TECHNIQUES TO IDENTIFY BURIED WASTE IN AN UNCONTROLLED LANDFILL AT THE PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

Energy Technology Data Exchange (ETDEWEB)

Miller, Peter T.; Starmer, R. John

2003-02-27

The primary objective of the investigation was to confirm the presence and determine the location of a cache of 30 to 60 buried 55-gallon drums that were allegedly dumped along the course of the pre-existing, northsouth diversion ditch (NSDD) adjacent to permitted landfills at the Paducah Gaseous Diffusion Plant, Kentucky. The ditch had been rerouted and was being filled and re-graded at the time of the alleged dumping. Historic information and interviews with individuals associated with alleged dumping activities indicated that the drums were dumped prior to the addition of other fill materials. In addition, materials alleged to have been dumped in the ditch, such as buried roofing materials, roof flashing, metal pins, tar substances, fly ash, and concrete rubble complicated data interpretation. Some clean fill materials have been placed over the site and graded. This is an environment that is extremely complicated in terms of past waste dumping activities, construction practices and miscellaneous landfill operations. The combination of site knowledge gained from interviews and research of existing site maps, variable frequency EM data, classical total magnetic field data and optimized GPR lead to success where a simpler less focused approach by other investigators using EM-31 and EM-61 electromagnetic methods and unfocused ground penetrating radar (GPR)did not produce results and defined no real anomalies. A variable frequency electromagnetic conductivity unit was used to collect the EM data at 3,030 Hz, 5,070 Hz, 8,430 Hz, and 14,010 Hz. Both in-phase and quadrature components were recorded at each station point. These results provided depth estimates for targets and some information on the subsurface conditions. A standard magnetometer was used to conduct the magnetic survey that showed the locations and extent of buried metal, the approximate volume of ferrous metal present within a particular area, and allowed estimation of approximate target depths. The GPR

10 CFR 40.4 - Definitions.

Science.gov (United States)

2010-01-01

... Corporation that is authorized by statute to lease the gaseous diffusion enrichment plants in Paducah... of the gaseous diffusion plants, or other facilities, pursuant to a plan for the privatization of... subject to these commitments, which in some cases involve an exchange of information on imports, exports...

Criticality safety concerns of uranium deposits in cascade equipment

International Nuclear Information System (INIS)

Plaster, M.J.

1996-01-01

The Paducah and Portsmouth Gaseous Diffusion Plants enrich uranium in the 235 U isotope by diffusing gaseous uranium hexafluoride (UF 6 ) through a porous barrier. The UF 6 gaseous diffusion cascade utilized several thousand open-quotes stagesclose quotes of barrier to produce highly enriched uranium (HEU). Historically, Portsmouth has enriched the Paducah Gaseous Diffusion Plant's product (typically 1.8 wt% 235 U) as well as natural enrichment feed stock up to 97 wt%. Due to the chemical reactivity of UF 6 , particularly with water, the formation of solid uranium deposits occur at a gaseous diffusion plant. Much of the equipment operates below atmospheric pressure, and deposits are formed when atmospheric air enters the cascade. Deposits may also be formed from UF 6 reactions with oil, UF 6 reactions with the metallic surfaces of equipment, and desublimation of UF 6 . The major deposits form as a result of moist air in leakage due to failure of compressor casing flanges, blow-off plates, seals, expansion joint convolutions, and instrument lines. This report describes criticality concerns and deposit disposition

Environmental program audit, Paducah Gaseous Diffusion Plant, Paducah, Kentucky. Final report

International Nuclear Information System (INIS)

1985-08-01

The environmental monitoring program, environmental control equipment and its use, and the facility's compliance with DOE orders, Federal and State laws and regulations were evaluated in this audit. No imminent threat to public health and safety was discovered. A needed quality assurance program is being added. Recommendations are given

Safety analysis report on the ''Paducah Tiger'' protective overpack for 10-ton cylinders of uranium hexafluoride

International Nuclear Information System (INIS)

Stitt, D.H.

1975-01-01

The ''Paducah Tiger'' is a protective overpack used in shipment of 10-ton cylinders of enriched UF 6 . The calculations and tests are described which made and which indicate that the overpack is in compliance with the type B packaging requirements of ERDA Manual Chapter 0529 and Title 10 Code Federal Regulations Part 71. (U.S.)

Biological assessment of the effects of construction and operation of a depleted uranium hexafluoride conversion facility at the Paducah, Kentucky, site.

Energy Technology Data Exchange (ETDEWEB)

Van Lonkhuyzen, R.

2005-09-09

The U.S. Department of Energy (DOE) Depleted Uranium Hexafluoride (DUF{sub 6}) Management Program evaluated alternatives for managing its inventory of DUF{sub 6} and issued the ''Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride'' (DUF{sub 6} PEIS) in April 1999 (DOE 1999). The DUF{sub 6} inventory is stored in cylinders at three DOE sites: Paducah, Kentucky; Portsmouth, Ohio; and East Tennessee Technology Park (ETTP), near Oak Ridge, Tennessee. In the Record of Decision for the DUF{sub 6} PEIS, DOE stated its decision to promptly convert the DUF6 inventory to a more stable chemical form. Subsequently, the U.S. Congress passed, and the President signed, the ''2002 Supplemental Appropriations Act for Further Recovery from and Response to Terrorist Attacks on the United States'' (Public Law No. 107-206). This law stipulated in part that, within 30 days of enactment, DOE must award a contract for the design, construction, and operation of a DUF{sub 6} conversion plant at the Department's Paducah, Kentucky, and Portsmouth, Ohio, sites, and for the shipment of DUF{sub 6} cylinders stored at ETTP to the Portsmouth site for conversion. This biological assessment (BA) has been prepared by DOE, pursuant to the National Environmental Policy Act of 1969 (NEPA) and the Endangered Species Act of 1974, to evaluate potential impacts to federally listed species from the construction and operation of a conversion facility at the DOE Paducah site.

Gaseous isotope correlation technique for safeguards at reprocessing facilities

International Nuclear Information System (INIS)

Ohkubo, Michiaki.

1988-03-01

The isotope correlation technique based on gaseous stable fission products can be used as a means of verifying the input measurement to fuel reprocessing plants. This paper reviews the theoretical background of the gaseous fission product isotope correlation technique. The correlations considered are those between burnup and various isotopic ratios of Kr and Xe nuclides. The feasibility of gaseous ICT application to Pu input accountancy of reprocessing facilities is also discussed. The technique offers the possibility of in situ measurement verification by the inspector. (author). 16 refs, 7 figs

Final environmental impact assessment of the Paducah Gaseous Diffusion Plant site, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

1982-08-01

This document considers: the need for uranium enrichment facilities; site location; plant description; and describes the power generating facilities in light of its existing environment. The impacts from continuing operations are compared with alternatives of shutdown, relocation, and alternative power systems. (PSB)

Some aspects of numerical analysis of turbulent gaseous and spray combustion

International Nuclear Information System (INIS)

Takagi, T.

1991-01-01

In this paper numerical calculations and analysis on turbulent non-premixed gaseous and spray combustion are reviewed. Attentions were paid to the turbulent flow and combustion modeling applicable to predicting the flow, mixing and combustion of gaseous fuels and sprays. Some of the computed results of turbulent gaseous non-premixed (diffusion) flames with and without swirl and transient spray combustion were compared with experimental ones to understand the processes in the flame and to assure how the computations predict the experiments

Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

International Nuclear Information System (INIS)

Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

1991-09-01

Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3

Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

Energy Technology Data Exchange (ETDEWEB)

Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

1991-09-01

Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3.

Gaseous nebulae

International Nuclear Information System (INIS)

Williams, R.E.

1976-01-01

Gaseous nebulae are large, tenuous clouds of ionized gas that are associated with hot stars and that emit visible light because of the energy that they receive from the ultraviolet radiation of the stars. Examples include H II regions, planetary nebulae, and nova/supernova remnants. The emphasis is on the physical processes that occur in gaseous nebulae as opposed to a study of the objects themselves. The introduction discusses thermodynamic vs. steady-state equilibrium and excitation conditions in a dilute radiation field. Subsequent sections take up important atomic processes in gaseous nebulae (particle--particle collision rates, radiative interaction rates, cross sections), the ionization equilibrium (sizes of H II regions, ionization of the heavier elements), kinetic temperature and energy balance (heating of the electrons, cooling of the electrons), and the spectra of gaseous nebulae (line fluxes in nebulae). 7 figures, 5 tables

Gaseous detectors for energy dispersive X-ray fluorescence analysis

Science.gov (United States)

Veloso, J. F. C. A.; Silva, A. L. M.

2018-01-01

The energy resolution capability of gaseous detectors is being used in the last years to perform studies on the detection of characteristic X-ray lines emitted by elements when excited by external radiation sources. One of the most successful techniques is the Energy Dispersive X-ray Fluorescence (EDXRF) analysis. Recent developments in the new generation of micropatterned gaseous detectors (MPGDs), triggered the possibility not only of recording the photon energy, but also of providing position information, extending their application to EDXRF imaging. The relevant features and strategies to be applied in gaseous detectors in order to better fit the requirements for EDXRF imaging will be reviewed and discussed, and some application examples will be presented.

Treatment of Radioactive Gaseous Waste

International Nuclear Information System (INIS)

2014-07-01

filtration of gaseous radioactive substances. It is also necessary to capture and condition the radioactive substances in the exhaust gas from the nuclear plant and equipment and the controlled zones. The second subsystem provides effective control and management of gaseous waste in normal and accidental conditions — one of the main issues of nuclear fuel cycle facility design and operation. Many of the issues relating to air cleaning and gaseous radioactive waste management systems have been covered in several IAEA publications. This publication is an attempt to provide systematic and comprehensive information on the entire subject. This publication takes into account the increasing requirements for the protection of the public and the environment, and during the publication’s preparation, the available technical information was collected and reviewed

CHANGING THE LANDSCAPE--LOW-TECH SOLUTIONS TO THE PADUCAH SCRAP METAL REMOVAL PROJECT ARE PROVIDING SAFE, COST-EFFECTIVE REMEDIATION OF CONTAMINATED SCRAP YARDS

International Nuclear Information System (INIS)

Watson, Dan; Eyman, Jeff

2003-01-01

Between 1974 and 1983, contaminated equipment was removed from the Paducah Gaseous Diffusion Plant (PGDP) process buildings as part of an enrichment process upgrade program. The upgrades consisted of the dismantlement, removal, and on-site storage of contaminated equipment, cell components, and scrap material (e.g., metal) from the cascade facilities. Scrap metal including other materials (e.g., drums, obsolete equipment) not related to this upgrade program have thus far accumulated in nine contiguous radiologically-contaminated and non-contaminated scrap yards covering 1.05E5 m2 (26 acres) located in the northwestern portion of the PGDP. This paper presents the sequencing of field operations and methods used to achieve the safe removal and disposition of over 47,000 tonnes (53,000 tons) of metal and miscellaneous items contained in these yards. The methods of accomplishment consist of mobilization, performing nuclear criticality safety evaluations, moving scrap metal to ground level, inspection and segregation, sampling and characterization, scrap metal sizing, packaging and disposal, and finally demobilization. Preventing the intermingling of characteristically hazardous and non-hazardous wastes promotes waste minimization, allowing for the metal and materials to be segregated into 13 separate waste streams. Low-tech solutions such as using heavy equipment to retrieve, size, and package scrap materials in conjunction with thorough planning that integrates safe work practices, commitment to teamwork, and incorporating lessons learned ensures that field operations will be conducted efficiently and safely

Characteristics and applications of small, portable gaseous air pollution monitors.

Science.gov (United States)

McKercher, Grant R; Salmond, Jennifer A; Vanos, Jennifer K

2017-04-01

Traditional approaches for measuring air quality based on fixed measurements are inadequate for personal exposure monitoring. To combat this issue, the use of small, portable gas-sensing air pollution monitoring technologies is increasing, with researchers and individuals employing portable and mobile methods to obtain more spatially and temporally representative air pollution data. However, many commercially available options are built for various applications and based on different technologies, assumptions, and limitations. A review of the monitor characteristics of small, gaseous monitors is missing from current scientific literature. A state-of-the-art review of small, portable monitors that measure ambient gaseous outdoor pollutants was developed to address broad trends during the last 5-10 years, and to help future experimenters interested in studying gaseous air pollutants choose monitors appropriate for their application and sampling needs. Trends in small, portable gaseous air pollution monitor uses and technologies were first identified and discussed in a review of literature. Next, searches of online databases were performed for articles containing specific information related to performance, characteristics, and use of such monitors that measure one or more of three criteria gaseous air pollutants: ozone, nitrogen dioxide, and carbon monoxide. All data were summarized into reference tables for comparison between applications, physical features, sensing capabilities, and costs of the devices. Recent portable monitoring trends are strongly related to associated applications and audiences. Fundamental research requires monitors with the best individual performance, and thus the highest cost technology. Monitor networking favors real-time capabilities and moderate cost for greater reproduction. Citizen science and crowdsourcing applications allow for lower-cost components; however important strengths and limitations for each application must be addressed

Diesel Engine Convert to Port Injection CNG Engine Using Gaseous Injector Nozzle Multi Holes Geometries Improvement: A Review

OpenAIRE

Semin; Abdul R. Ismail; Rosli A. Bakar

2009-01-01

The objective of this study was to review the previous research in the development of gaseous fuel injector for port injection CNG engine converted from diesel engine. Problem statement: The regular development of internal combustion engines change direction to answer the two most important problems determining the development trends of engines technology and in particular, their combustion systems. They were environmental protection against emission and noise, shortage of hydrocarbon fuels, ...

INVESTIGATION OF HOLOCENE FAULTING PROPOSED C-746-U LANDFILL EXPANSION

Energy Technology Data Exchange (ETDEWEB)

Lettis, William [William Lettis & Associates, Inc.

2006-07-01

This report presents the findings of a fault hazard investigation for the C-746-U landfill's proposed expansion located at the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP), in Paducah, Kentucky. The planned expansion is located directly north of the present-day C-746-U landfill. Previous geophysical studies within the PGDP site vicinity interpret possible northeast-striking faults beneath the proposed landfill expansion, although prior to this investigation the existence, locations, and ages of these inferred faults have not been confirmed through independent subsurface exploration. The purpose of this investigation is to assess whether or not Holocene-active fault displacement is present beneath the footprint of the proposed landfill expansion.

Development of gaseous photomultiplier

International Nuclear Information System (INIS)

Tokanai, F.; Sumiyoshi, T.; Sugiyama, H.; Okada, T.

2014-01-01

We have been developing gaseous photomultiplier tubes (PMTs) with alkali photocathode combined with micropattern gas detectors (MPGDs). The potential advantage of the gaseous PMT is that it can achieve a very large effective area with adequate position and timing resolutions. In addition, it will be easily operated under a very high magnetic field, compared with the conventional vacuum-based PMT. To evaluate the gaseous PMTs filled with Ne and Ar based gas mixture, we have developed gaseous PMTs with an alkali photocathode combined with MPGDs such as a glass capillary plate, GEM, and Micromegas detector. We describe the recent development of the gaseous PMTs, particularly the production of the photocathode, gas gain, ion and photon feedbacks, quantum efficiency, and the characteristics in the magnetic field environment. (author)

Electron impact phenomena and the properties of gaseous ions

CERN Document Server

Field, F H; Massey, H S W; Brueckner, Keith A

1970-01-01

Electron Impact Phenomena and the Properties of Gaseous Ions, Revised Edition deals with data pertaining to electron impact and to molecular gaseous ionic phenomena. This book discusses electron impact phenomena in gases at low pressure that involve low-energy electrons, which result in ion formation. The text also describes the use of mass spectrometers in electron impact studies and the degree of accuracy obtained when measuring electron impact energies. This book also reviews relatively low speed electrons and the transitions that result in the ionization of the atomic system. This text the

Gaseous poison injection device

International Nuclear Information System (INIS)

Kubota, Ryuji; Sugisaki, Toshihiko; Inada, Ikuo.

1983-01-01

Purpose: To rapidly control the chain reaction due to thermal neutrons in a reactor core by using gaseous poisons as back-up means for control rod drives. Constitution: Gaseous poisons having a large neutron absorption cross section are used as back-up means for control rod drives. Upon failure of control rod insertion, the gaseous poisons are injected into the lower portion of the reactor core to control the reactor power. As the gaseous poisons, vapors at a high temperature and a higher pressure than that of the coolants in the reactor core are injected to control the reactor power due to the void effects. Since the gaseous poisons thus employed rapidly reach the reactor core and form gas bubbles therein, the deccelerating effect of the thermal neutrons is decreased to reduce the chain reaction. (Moriyama, K.)

Basic processes and trends in gaseous detectors

CERN Multimedia

1999-01-01

Almost a century after the invention of the proportional counter, a large research effort is still devoted to better understand the basic properties of gaseous detectors, and to improve their performances and reliability, particularly in view of use at the high radiation levels expected at LHC. In the first part of the lectures, after a brief introduction on underlying physical phenomena, I will review modern sophisticated computational tools, as well as some classic "back of the envelope" analytical methods, available today for estimating the general performances of gaseous detectors. In the second part, I will analyze in more detail problems specific to the use of detectors at high rates (space charge, discharges, aging), and describe the recent development of powerful and perhaps more reliable devices, particularly in the field of position-sensitive micro-pattern detectors.

Chapter 4 Gaseous Elemental Mercury in the Ambient Atmosphere

DEFF Research Database (Denmark)

Ariya, Parisa A.; Skov, Henrik; Grage, Mette M L

2008-01-01

Understanding the kinetics and mechanisms associated with the atmospheric chemistry of mercury is of great importance to protecting the environment. This review will focus on theoretical calculations to advance understanding of gas phase oxidation of gaseous elemental mercury (GEM) by halogen spe...

Sampling technologies and air pollution control devices for gaseous and particulate arsenic: a review

International Nuclear Information System (INIS)

Helsen, Lieve

2005-01-01

Direct measurement of arsenic release requires a good sampling and analysis procedure in order to capture and detect the total amount of metals emitted. The literature is extensively reviewed in order to evaluate the efficiency of full field-scale and laboratory scale techniques for capturing particulate and gaseous emissions of arsenic from the thermo-chemical treatment of different sources of arsenic. Furthermore, trace arsenic concentrations in ambient air, national standard sampling methods and arsenic analysis methods are considered. Besides sampling techniques, the use of sorbents is also reviewed with respect to both approaches (1) to prevent the metals from exiting with the flue gas and (2) to react or combine with the metals in order to be collected in air pollution control systems. The most important conclusion is that submicron arsenic fumes are difficult to control in conventional air pollution control devices. Complete capture of the arsenic species requires a combination of particle control and vapour control devices. - Submicron arsenic fumes are difficult to control in conventional air pollution control devices

Liquid and Gaseous Waste Operations Department annual operating report CY 1996

International Nuclear Information System (INIS)

Maddox, J.J.; Scott, C.B.

1997-03-01

This annual report summarizes operating activities dealing with the process waste system, the liquid low-level waste system, and the gaseous waste system. It also describes upgrade activities dealing with the process and liquid low-level waste systems, the cathodic protection system, a stack ventilation system, and configuration control. Maintenance activities are described dealing with nonradiological wastewater treatment plant, process waste treatment plant and collection system, liquid low-level waste system, and gaseous waste system. Miscellaneous activities include training, audits/reviews/tours, and environmental restoration support

Aging phenomena in gaseous detectors - perspectives from the 2001 workshop

CERN Document Server

Hohlmann, M; Tesch, N; Titov, M

2002-01-01

High-Energy Physics experiments are currently entering a new era which requires the operation of gaseous particle detectors at unprecedented high rates and integrated particle fluxes. Full functionality of such detectors over the lifetime of an experiment in a harsh radiation environment is of prime concern. New classes of gaseous detectors such as large-scale straw-type detectors, Micro-pattern Gas Detectors, and resistive plate chambers--each with their own specific aging characteristics--have evolved since the first workshop on wire chamber aging was held at LBL, Berkeley in 1986. The 2001 workshop provided a forum to review the progress since 1986 in understanding aging effects and to exchange recent experiences. A summary of the main results reported at the 2001 workshop is presented providing a systematic review of aging effects in state-of-the-art detectors.

Effect of engine parameters and type of gaseous fuel on the performance of dual-fuel gas diesel engines. A critical review

Energy Technology Data Exchange (ETDEWEB)

Sahoo, B.B. [Centre for Energy, Indian Institute of Technology, Guwahati 781039 (India); Sahoo, N.; Saha, U.K. [Department of Mechanical Engineering, Indian Institute of Technology, Guwahati 781039 (India)

2009-08-15

Petroleum resources are finite and, therefore, search for their alternative non-petroleum fuels for internal combustion engines is continuing all over the world. Moreover gases emitted by petroleum fuel driven vehicles have an adverse effect on the environment and human health. There is universal acceptance of the need to reduce such emissions. Towards this, scientists have proposed various solutions for diesel engines, one of which is the use of gaseous fuels as a supplement for liquid diesel fuel. These engines, which use conventional diesel fuel and gaseous fuel, are referred to as 'dual-fuel engines'. Natural gas and bio-derived gas appear more attractive alternative fuels for dual-fuel engines in view of their friendly environmental nature. In the gas-fumigated dual-fuel engine, the primary fuel is mixed outside the cylinder before it is inducted into the cylinder. A pilot quantity of liquid fuel is injected towards the end of the compression stroke to initiate combustion. When considering a gaseous fuel for use in existing diesel engines, a number of issues which include, the effects of engine operating and design parameters, and type of gaseous fuel, on the performance of the dual-fuel engines, are important. This paper reviews the research on above issues carried out by various scientists in different diesel engines. This paper touches upon performance, combustion and emission characteristics of dual-fuel engines which use natural gas, biogas, producer gas, methane, liquefied petroleum gas, propane, etc. as gaseous fuel. It reveals that 'dual-fuel concept' is a promising technique for controlling both NO{sub x} and soot emissions even on existing diesel engine. But, HC, CO emissions and 'bsfc' are higher for part load gas diesel engine operations. Thermal efficiency of dual-fuel engines improve either with increased engine speed, or with advanced injection timings, or with increased amount of pilot fuel. The ignition

Handling of UF6 in U.S. gaseous diffusion plants

International Nuclear Information System (INIS)

Legeay, A.J.

1978-01-01

A comprehensive systems analysis of UF 6 handling has been made in the three U.S. gaseous diffusion plants and has resulted in a significant impact on the equipment design and the operating procedures of these facilities. The equipment, facilities, and industrial practices in UF 6 handling operations as they existed in the early 1970's are reviewed with particular emphasis placed on the changes which have been implemented. The changes were applied to the systems and operating methods which evolved from the design, startup, and operation of the Oak Ridge Gaseous Diffusion Plant in 1945

Gaseous Matter

CERN Document Server

Angelo, Joseph A

2011-01-01

aseous Matter focuses on the many important discoveries that led to the scientific interpretation of matter in the gaseous state. This new, full-color resource describes the basic characteristics and properties of several important gases, including air, hydrogen, helium, oxygen, and nitrogen. The nature and scope of the science of fluids is discussed in great detail, highlighting the most important scientific principles upon which the field is based. Chapters include:. Gaseous Matter An Initial Perspective. Physical Characteristics of Gases. The Rise of the Science of Gases. Kinetic Theory of

Network user's guide

International Nuclear Information System (INIS)

McGrady, P.W.

1994-12-01

NETWORK is a FORTRAN code used to model process flow systems in the gaseous diffusion plants at Portsmouth, Ohio and Paducah, Kentucky, operated by the United States Enrichment Corporation. It can handle a wide range of components and several different types of controllers. NETWORK can be run in either a steady-state mode or a transient mode. In the transient mode many different types of perturbations may be modeled. It is currently being used to model taking a cell off-stream in a gaseous diffusion plant. A brief description of the code is given, and process equipment models and input data are discussed

Community Visions for the Paducah Gaseous Diffusion Plant Site

Energy Technology Data Exchange (ETDEWEB)

Ormsbee, Lindell e [Civil Engineering, Univ. of KY; Kipp, James A [Univ. of KY, Kentucky water research Institute

2011-09-01

This report focuses on assessing community preferences for the future use of the PGDP site, given the site's pending closure by US DOE. The project approach fostered interaction and engagement with the public based on lessons learned at other complex DOE environmental cleanup sites and upon the integration of a number of principles and approaches to public engagement from the Project Team's local, state, regional and international public engagement experience. The results of the study provide the community with a record of the diversity of values and preferences related to the environmental cleanup and future use of the site.

Paducah Gaseous Diffusion Plant site environmental report for 1988

International Nuclear Information System (INIS)

Rogers, J.G.; Jett, T.G.

1989-05-01

Quantities of nonradiological chemical emissions are not included in this report this year. An addendum that will include the information will be published after the Superfund Amendments Reauthorization Act (SARA) Title III report is issued on July 1, 1989. When the addendum is published, probably in late July, a summary of the SARA Title III 313 report will be included. The SARA report provides the community with the opportunity to lean about estimated quantities of certain toxic chemicals used at a facility that are routinely or accidentally released into the environment. The addendum that will be published after the SARA report will summarize the SARA report and is expected to include some additional ''large quantity'' chemicals used or stored at the facilities that are not required to be reported by SARA Title III but are known to be emitted from the facilities. The addendum will not be all inclusive but will provide emissions information on the major chemical emissions to the air, water, or land from processes at the facilities

DOE site performance assessment activities

International Nuclear Information System (INIS)

1990-07-01

Information on performance assessment capabilities and activities was collected from eight DOE sites. All eight sites either currently dispose of low-level radioactive waste (LLW) or plan to dispose of LLW in the near future. A survey questionnaire was developed and sent to key individuals involved in DOE Order 5820.2A performance assessment activities at each site. The sites surveyed included: Hanford Site (Hanford), Idaho National Engineering Laboratory (INEL), Los Alamos National Laboratory (LANL), Nevada Test Site (NTS), Oak Ridge National Laboratory (ORNL), Paducah Gaseous Diffusion Plant (Paducah), Portsmouth Gaseous Diffusion Plant (Portsmouth), and Savannah River Site (SRS). The questionnaire addressed all aspects of the performance assessment process; from waste source term to dose conversion factors. This report presents the information developed from the site questionnaire and provides a comparison of site-specific performance assessment approaches, data needs, and ongoing and planned activities. All sites are engaged in completing the radioactive waste disposal facility performance assessment required by DOE Order 5820.2A. Each site has achieved various degrees of progress and have identified a set of critical needs. Within several areas, however, the sites identified common needs and questions

Emission of gaseous organic pollutants and flue gas treatment technology

International Nuclear Information System (INIS)

Chmielewski, A.G.; Sun, Y.

2007-01-01

Gaseous organic pollutants are emitted into atmosphere from various sources, creating a threat to the environment and man. New, economical technologies are needed for flue gas treatment. Emission sources of pollutants are reviewed and different treatment technologies are discussed in this report. (authors)

Monitoring of released radioactive gaseous and liquid effluent at Rokkasho Reprocessing Plant

International Nuclear Information System (INIS)

Oka, M.; Keta, S.; Nagai, S.; Kano, M.; Ishihara, N.; Moriyama, T.; Ogaki, K.; Noda, K.

2009-01-01

Rokkasho Reprocessing Plant (RRP) Rokkasho Reprocessing Plant started its active tests with spent fuel at the end of March 2006. When spent fuels are sheared and dissolved, radioactive gaseous effluent and radioactive liquid effluent such as krypton-85, tritium, etc. are released into the environment. In order to limit the public dose as low as reasonably achievable in an efficient way, RRP removes radioactive material by evaporation, rinsing, filtering, etc., and then releases it through the main stack and the sea discharge pipeline that allow to make dispersion and dilution very efficiently. Also, concerning the radioactive gaseous and liquid effluent to be released into the environment, the target values of annual release have been defined in the Safety Rule based on the estimated annual release evaluated at the safety review of RRP. By monitoring the radioactive material in gaseous exhaust and liquid effluent RRP controls it not to exceed the target values. RRP reprocessed 430 tUpr of spent fuel during Active Test (March 2006 to October 2008). In this report, we report about: The outline of gaseous and liquid effluent monitoring. The amount of radioactive gaseous and liquid effluent during the active test. The performance of removal of radioactive materials in gaseous and liquid effluents. The impact on the public from radioactive effluents during the active test. (author)

Safety analysis report on the ''Paducah Tiger'' overpack for 10-ton cylinder of uranium hexafluoride

International Nuclear Information System (INIS)

Stitt, D.H.

1978-01-01

A summary of analysis performed to assess the puncture resistance of the Paducah Tiger under a particularly severe (worst case) orientation of the external puncture pin is presented. The six-inch diameter cylindrical puncture pin has been oriented to place its impact location immediately opposite the valve body mounted to the dished head of the uranium hexafluoride cylinder. The valve body is assumed to have a one-inch clearance relative to the inner wall of the overpack. Analysis indicates that significant residual kinetic energy remains in the system at the instant of overpack inner wall contact with the valve body. Thus, there is strong evidence suggesting that the valve body can be damaged, or sheared from the dished head of the UF 6 , under the assumed worst case impact orientation

Plant air systems safety study: Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

1982-05-01

The Portsmouth Gaseous Diffusion Plant Air System facilities and operations are reviewed for potential safety problems not covered by standard industrial safety procedures. Information is presented under the following section headings: facility and process description (general); air plant equipment; air distribution system; safety systems; accident analysis; plant air system safety overview; and conclusion

ORO scrap metal decontamination program

International Nuclear Information System (INIS)

Jugan, M.

1987-01-01

The Oak Ridge Operations Office (ORO) of the US Department of Energy (DOE) has approximately 80,000 tons of contaminated scrap metal at the Oak Ridge Gaseous Diffusion Plant in Oak Ridge, Tennessee; Paducah Gaseous Diffusion Plant in Paducah, Kentucky; Portsmouth Gaseous Diffusion Plant in Piketon, Ohio; and the Feed Materials Production Center in Fernald, Ohio. After unsuccessful in-house attempts to eliminate/recycle the contaminated metal, DOE is allowing private enterprise the opportunity to participate in this program. DOE is making this opportunity available under a two-phase approach, which is being supported by two separate and corresponding Request for Proposals. Phase I, which is nearing completion, is a demonstration phase to establish a group of companies that the DOE will consider qualified to eliminate the scrap at one or more sites. In Phase I, the companies decontaminated 25-50 tons of scrap to demonstrate capabilities to DOE and to gain the knowledge required to plan/bid on elimination of the scrap at one or more sites. Phase II will request proposals for elimination of the total scrap at one or more of the above noted sites. Multiple awards for Phase II are also anticipated. Companies participating in Phase II will be required to take title to the contaminated scrap and decontaminate/process the scrap for beneficial reuse. Radioactive wastes and metal that cannot be successfully decontaminated/processed will be returned to DOE

Gaseous waste processing facility

International Nuclear Information System (INIS)

Konno, Masanobu; Uchiyama, Yoshio; Suzuki, Kunihiko; Kimura, Masahiro; Kawabe, Ken-ichi.

1992-01-01

Gaseous waste recombiners 'A' and 'B' are connected in series and three-way valves are disposed at the upstream and the downstream of the recombiners A and B, and bypass lines are disposed to the recombiners A and B, respectively. An opening/closing controller for the three-way valves is interlocked with a hydrogen densitometer disposed to a hydrogen injection line. Hydrogen gas and oxygen gas generated by radiolysis in the reactor are extracted from a main condenser and caused to flow into a gaseous waste processing system. Gaseous wastes are introduced together with overheated steams to the recombiner A upon injection of hydrogen. Both of the bypass lines of the recombiners A and B are closed, and recombining reaction for the increased hydrogen gas is processed by the recombiners A and B connected in series. In an operation mode not conducting hydrogen injection, it is passed through the bypass line of the recombiner A and processed by the recombiner B. With such procedures, the increase of gaseous wastes due to hydrogen injection can be coped with existent facilities. (I.N.)

National Gas Survey. Synthesized gaseous hydrocarbon fuels

Energy Technology Data Exchange (ETDEWEB)

None

1978-06-01

The supply-Technical Advisory Task Force-Synthesized Gaseous Hydrocarbon Fuels considered coal, hydrocarbon liquids, oil shales, tar sands, and bioconvertible materials as potential feedstocks for gaseous fuels. Current status of process technology for each feedstock was reviewed, economic evaluations including sensitivity analysis were made, and constraints for establishment of a synthesized gaseous hydrocarbon fuels industry considered. Process technology is presently available to manufacture gaseous hydrocarbon fuels from each of the feedstocks. In 1975 there were eleven liquid feedstock SNG plants in the United States having a capacity of 1.1 billion SCFD. There can be no contribution of SNG before 1982 from plants using feedstocks other than liquids because there are no plants in operation or under construction as of 1977. Costs for SNG are higher than current regulated prices for U.S. natural gas. Because of large reserves, coal is a prime feedstock candidate although there are major constraints in the area of coal leases, mining and water permits, and others. Commercial technology is available and several new gasification processes are under development. Oil shale is also a feedstock in large supply and commercial process technology is available. There are siting and permit constraints, and water availability may limit the ultimate size of an oil shale processing industry. Under projected conditions, bioconvertible materials are not expected to support the production of large quantities of pipeline quality gas during the next decade. Production of low or medium Btu gas from municipal solid wastes can be expected to be developed in urban areas in conjunction with savings in disposal costs. In the economic evaluations presented, the most significant factor for liquid feedstock plants is the anticipated cost of feedstock and fuel. The economic viability of plants using other feedstocks is primarily dependent upon capital requirements.

Gaseous Electron Multiplier (GEM) Detectors

Science.gov (United States)

Gnanvo, Kondo

2017-09-01

Gaseous detectors have played a pivotal role as tracking devices in the field of particle physics experiments for the last fifty years. Recent advances in photolithography and micro processing techniques have enabled the transition from Multi Wire Proportional Chambers (MWPCs) and Drift Chambers to a new family of gaseous detectors refer to as Micro Pattern Gaseous Detectors (MPGDs). MPGDs combine the basic gas amplification principle with micro-structure printed circuits to provide detectors with excellent spatial and time resolution, high rate capability, low material budget and high radiation tolerance. Gas Electron Multiplier (GEMs) is a well-established MPGD technology invented by F. Sauli at CERN in 1997 and deployed various high energy physics (HEP) and nuclear NP experiment for tracking systems of current and future NP experiments. GEM detector combines an exceptional high rate capability (1 MHz / mm2) and robustness against harsh radiation environment with excellent position and timing resolution performances. Recent breakthroughs over the past decade have allowed the possibility for large area GEMs, making them cost effective and high-performance detector candidates to play pivotal role in current and future particle physics experiments. After a brief introduction of the basic principle of GEM technology, I will give a brief overview of the GEM detectors used in particle physics experiments over the past decades and especially in the NP community at Thomas Jefferson National Laboratory (JLab) and Brookhaven National Laboratory (BNL). I will follow by a review of state of the art of the new GEM development for the next generation of colliders such as Electron Ion Collider (EIC) or High Luminosity LHC and future Nuclear Physics experiments. I will conclude with a presentation of the CERN-based RD51 collaboration established in 2008 and its major achievements regarding technological developments and applications of MPGDs.

Gaseous radioactive waste processing system

International Nuclear Information System (INIS)

Onizawa, Hideo.

1976-01-01

Object: To prevent explosion of hydrogen gas within gaseous radioactive waste by removing the hydrogen gas by means of a hydrogen absorber. Structure: A coolant extracted from a reactor cooling system is sprayed by nozzle into a gaseous phase (hydrogen) portion within a tank, thus causing slipping of radioactive rare gas. The gaseous radioactive waste rich in hydrogen, which is purged in the tank, is forced by a waste gas compressor into a hydrogen occlusion device. The hydrogen occlusion device is filled with hydrogen occluding agents such as Mg, Mg-Ni alloy, V-Nb alloy, La-Ni alloy and so forth, and hydrogen in the waste gas is removed through reaction to produce hydrogen metal. The gaseous radioactive waste, which is deprived of hydrogen and reduced in volume, is stored in an attenuation tank. The hydrogen stored in the hydrogen absorber is released and used again as purge gas. (Horiuchi, T.)

Prediction of external corrosion for steel cylinders

International Nuclear Information System (INIS)

Lyon, B.F.

1997-02-01

The US Department of Energy (DOE) currently manages the UF 6 Cylinder Program (the program). The program was formed to address the depleted-uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the K-25 site (K-25) at Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1996a) delineates the requirements of the program. The appropriate actions needed to fulfill these requirements are then specified within the System Engineering Management Plan (SEMP) (LMES 1996b). The report presented herein documents activities that in whole or in part satisfy specific requirements and actions stated in the UF 6 Cylinder Program SRD and SEMP with respect to forecasting cylinder conditions. The wall thickness projections made in this report are based on the assumption that the corrosion trends noted will continue. Some activities planned may substantially reduce the rate of corrosion, in which case the results presented here are conservative. The results presented here are intended to supersede those presented previously, as the quality of several of the datasets has improved

Introduction to investigations of the negative corona and EHD flow in gaseous two-phase fluids

Science.gov (United States)

Jerzy, MIZERACZYK; Artur, BERENDT

2018-05-01

Research interests have recently been directed towards electrical discharges in multi-phase environments. Natural electrical discharges, such as lightning and coronas, occur in the Earth’s atmosphere, which is actually a mixture of gaseous phase (air) and suspended solid and liquid particulate matters (PMs). An example of an anthropogenic gaseous multi-phase environment is the flow of flue gas through electrostatic precipitators (ESPs), which are generally regarded as a mixture of a post-combustion gas with solid PM and microdroplets suspended in it. Electrical discharges in multi-phase environments, the knowledge of which is scarce, are becoming an attractive research subject, offering a wide variety of possible discharges and multi-phase environments to be studied. This paper is an introduction to electrical discharges in multi-phase environments. It is focused on DC negative coronas and accompanying electrohydrodynamic (EHD) flows in a gaseous two-phase fluid formed by air (a gaseous phase) and solid PM (a solid phase), run under laboratory conditions. The introduction is based on a review of the relevant literature. Two cases will be considered: the first case is of a gaseous two-phase fluid, initially motionless in a closed chamber before being subjected to a negative corona (with the needle-to-plate electrode arrangement), which afterwards induces an EHD flow in the chamber, and the second, of a gaseous two-phase fluid flowing transversely with respect to the needle-to-plate electrode axis along a chamber with a corona discharge running between the electrodes. This review-based introductory paper should be of interest to theoretical researchers and modellers in the field of negative corona discharges in single- or two-phase fluids, and for engineers who work on designing EHD devices (such as ESPs, EHD pumps, and smoke detectors).

Mass spectrometric study of thermodynamic properties of gaseous lead tellurates. Estimation of formation enthalpies of gaseous lead polonates

Energy Technology Data Exchange (ETDEWEB)

Shugurov, S.M., E-mail: s.shugurov@spbu.ru; Panin, A.I.; Lopatin, S.I.; Emelyanova, K.A.

2016-10-15

Gaseous reactions involving lead oxides, tellurium oxide and lead tellurates were studied by the Knudsen effusion mass spectrometry. Equilibrium constants and reaction enthalpies were evaluated. Structures, molecular parameters and thermodynamic functions of gaseous PbTeO{sub 3} and Pb{sub 2}TeO{sub 4} were calculated by quantum chemistry methods. The formation enthalpies Δ{sub f}H{sup 0} (298.15) = −294 ± 13 for gaseous PbTeO{sub 3} and Δ{sub f}H{sup 0} (298.15) = −499 ± 12 for gaseous Pb{sub 2}TeO{sub 4} were obtained. On the base of these results the formation enthalpies of gaseous PbPoO{sub 3} and Pb{sub 2}PoO{sub 4} were estimated as −249 ± 34 and −478 ± 38, respectively. - Highlights: • Gaseous lead tellurates PbTeO{sub 3}, Pb{sub 2}TeO{sub 4} were discovered. • Their thermodynamic properties were studied using both high temperature mass spectrometry and quantum chemistry computations. • The obtained data allows to predict the formation enthalpies of gaseous lead polonates PbPoO{sub 3}, Pb{sub 2}PoO{sub 4}.

7th International Symposium on Gaseous Dielectrics

CERN Document Server

James, David

1994-01-01

The Seventh International Symposium on Gaseous Dielectrics was held in Knoxville, Tennessee, U. S. A. , on April 24-28, 1994. The symposium continued the interdisciplinary character and comprehensive approach of the preceding six symposia. Gaseous DielecIries VII is a detailed record of the symposium proceedings. It covers recent advances and developments in a wide range of basic, applied and industrial areas of gaseous dielectrics. It is hoped that Gaseous DielecIries VII will aid future research and development in, and encourage wider industrial use of, gaseous dielectrics. The Organizing Committee of the Seventh International Symposium on Gaseous Dielectrics consisted of G. Addis (U. S. A. ), L. G. Christophorou (U. S. A. ), F. Y. Chu (Canada), A. H. Cookson (U. S. A. ), O. Farish (U. K. ), I. Gallimberti (Italy) , A. Garscadden (U. S. A. ), D. R. James (U. S. A. ), E. Marode (France), T. Nitta (Japan), W. Pfeiffer (Germany), Y. Qiu (China), I. Sauers (U. S. A. ), R. J. Van Brunt (U. S. A. ), and W. Zaengl...

The conditions of gaseous fuels development

International Nuclear Information System (INIS)

Anon.

1996-01-01

Face to the actual situation of petrol and gas oil in France, the situation of gaseous fuels appears to be rather modest. However, the aim of gaseous fuels is not to totally supersede the liquid fuels. Such a situation would imply a complete overturn which has not been seriously considered yet. This short paper describes the essential conditions to promote the wider use of gaseous fuels: the intervention of public authorities to adopt a more advantageous tax policy in agreement with the ''Clean Air''law project, a suitable distribution network for gaseous fuels, a choice of vehicles consistent with the urban demand, the development of transformation kits of quality and of dual-fuel vehicles by the car manufacturers. (J.S.)

Position-sensitive gaseous photomultipliers research and applications

CERN Document Server

Francke, Tom; Peskov, Vladimir

2016-01-01

Gaseous photomultipliers are defined as gas-filled devices capable of recording single ultraviolet (UV) and visible photons with high position resolution. Used in a variety of research areas, these detectors can be paired with computers to treat and store imaging information of UV-light. Position-Sensitive Gaseous Photomultipliers: Research and Applications explores the advancement of gaseous detectors as applied for single photon detection. Emphasizing emerging perspectives and new ways to apply gaseous detectors across research fields, this research-based publication is an essential reference source for engineers, physicists, graduate-level students, and researchers.

Inhalation gases or gaseous mediators as neuroprotectants for cerebral ischaemia.

Science.gov (United States)

Sutherland, Brad A; Harrison, Joanne C; Nair, Shiva M; Sammut, Ivan A

2013-01-01

Ischaemic stroke is one of the leading causes of morbidity and mortality worldwide. While recombinant tissue plasminogen activator can be administered to produce thrombolysis and restore blood flow to the ischaemic brain, therapeutic benefit is only achieved in a fraction of the subset of patients eligible for fibrinolytic intervention. Neuroprotective therapies attempting to restrict the extent of brain injury following cerebral ischaemia have not been successfully translated into the clinic despite overwhelming pre-clinical evidence of neuroprotection. Therefore, an adequate treatment for the majority of acute ischaemic stroke patients remains elusive. In the stroke literature, the use of therapeutic gases has received relatively little attention. Gases such as hyperbaric and normobaric oxygen, xenon, hydrogen, helium and argon all possess biological effects that have shown to be neuroprotective in pre-clinical models of ischaemic stroke. There are significant advantages to using gases including their relative abundance, low cost and feasibility for administration, all of which make them ideal candidates for a translational therapy for stroke. In addition, modulating cellular gaseous mediators including nitric oxide, carbon monoxide, and hydrogen sulphide may be an attractive option for ischaemic stroke therapy. Inhalation of these gaseous mediators can also produce neuroprotection, but this strategy remains to be confirmed as a viable therapy for ischaemic stroke. This review highlights the neuroprotective potential of therapeutic gas therapy and modulation of gaseous mediators for ischaemic stroke. The therapeutic advantages of gaseous therapy offer new promising directions in breaking the translational barrier for ischaemic stroke.

Trapping technology for gaseous fission products from voloxidation process

International Nuclear Information System (INIS)

Shin, Jin Myeong; Park, J. J.; Park, G. I.; Jung, I. H.; Lee, H. H.; Kim, G. H.; Yang, M. S.

2005-05-01

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, 14 C, Kr, Xe, I and 3 H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and 14 C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion media to HTO for 3 H. This report will be used as a useful means for analyzing the known trapping technologies and help selecting the appropriate trapping methods for trapping volatile and semi-volatile fission products, long-lived fission products, and major heat sources generated from a voloxidation process. It can also be used to design an off-gas treatment system

Separation of tritium from gaseous and aqueous effluent systems

International Nuclear Information System (INIS)

Kobisk, E.H.

1977-01-01

Removal or reduction of tritium content in a wide variety of effluent streams has been extensively studied in the United States. This paper specifically reviews three processes involving tritium separation in the gaseous phase and the aqueous phase. Diffusion through a selective Pd-25Ag alloy membrane at temperatures up to 600 0 C and at pressures up to 700 kg/cm 2 has resulted in successful separation of hydrogen-deuterium mixtures with an associated separation factor of 1.65 (and gives a calculated separation factor for hydrogen-tritium mixtures of 2.0). Use of a single palladium bipolar membrane in an electrolysis system has been found to yield a hydrogen-deuterium separation factor of 4 and a hydrogen-tritium factor of 6 to 11 without the production of gaseous hydrogen. Finally, countercurrent catalytic exchange between tritium-containing hydrogen gas and water has yielded a separation factor of 6.3. The specific advantages of each of these systems will be discussed in terms of their potential applications. In all cases, further investigations are necessary to scale the systems to handle large quantities of feed material in a continuous mode and to minimize energy requirements. Such separative systems must necessarily be cascaded to yield gaseous or aqueous product streams suitable for recycling to the tritium producing systems, for storage or for discharge to the environment. (orig./HP) [de

Dielectrophoretic separation of gaseous isotopes

International Nuclear Information System (INIS)

McConnell, D.B.

1976-01-01

This invention relates to a process for the separation of gaseous isotopes by electrophoresis assisted by convective countercurrent flow and to an apparatus for use in the process. The invention is especially applicable to heavy water separation from steam; however, it is to be understood that the invention is broadly applicable to the separation of gaseous isotopes having different dipole moments and/or different molecular weights. (author)

Hydrogen and Gaseous Fuel Safety and Toxicity

Energy Technology Data Exchange (ETDEWEB)

Lee C. Cadwallader; J. Sephen Herring

2007-06-01

Non-traditional motor fuels are receiving increased attention and use. This paper examines the safety of three alternative gaseous fuels plus gasoline and the advantages and disadvantages of each. The gaseous fuels are hydrogen, methane (natural gas), and propane. Qualitatively, the overall risks of the four fuels should be close. Gasoline is the most toxic. For small leaks, hydrogen has the highest ignition probability and the gaseous fuels have the highest risk of a burning jet or cloud.

Method of separating tritium contained in gaseous wastes

International Nuclear Information System (INIS)

Hashimoto, Yasuo; Oozono, Hideaki.

1981-01-01

Purpose: To decrease tritium concentration in gaseous wastes to less than the allowable level by removing tritium in gaseous wastes generated upon combustion of radioactive wastes by using a plurality of heat exchangers. Method: Gaseous wastes at high temperature generated upon combustion of radioactive wastes in an incinerator are removed with radioactive solid substances through filters, cooled down to a temperature below 10 0 C by the passage through first and second heat exchangers and decreased with tritium content to less than the allowable concentration by the gaseous wastes at low temperature from the second heat exhcanger. The gaseous wastes at low temperature are used as the cooling medium for the first heat exchanger. They are heat exchanged at the upstream of the second heat exchanger with the cooling water from the third heat exchanger and cooled at the downstream by the cooling water cooled by the cooling medium. The gaseous wastes at low temperature thus cooled below 10 0 C are heated to about 350 0 C in the first heat exchanger and discharged. (Moriyama, K.)

Final report. Paducah Gaseous Diffusion Plant PCB sediment survey: Big Bayou Creek and Little Bayou Creek, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

None

1996-12-01

Laboratory analysis of collected samples along drainage features at PGDP. Report documents levels of PCB contamination and considers locations of contamination and known releases to theorize probable sources to further investigate.

Installation of an innovative remedial technology

International Nuclear Information System (INIS)

Hines, B.

1995-01-01

The major goal of the Lasagna trademark project was to design, construct, install, and operate an in situ remediation system in low-permeability soil. A new technology--the Lasagna process--uses electro-osmosis to move contaminated groundwater through treatment zones. The treatment zones are installed in contaminated soils, thereby forming an integrated in situ remedial process. Electro-osmosis, well known for its effectiveness and extremely low power consumption, uses a direct current to cause Groundwater to travel through low-permeability soil. When a bench-scale version of the technology was 98 percent effective in removing contamination, an actual field test was the next step. The site chosen for this first field effort was the DOE-owned Paducah Gaseous Diffusion Plant located in Paducah, Kentucky. The target contaminant for this project was trichloroethylene (TCE) because it is found at many sites across the country and is present at approximately 60 percent of DOE's sites

Proceedings of the 1980 UCC-ND and GAT waste management seminar

Energy Technology Data Exchange (ETDEWEB)

None

1980-12-01

Papers and/or abstracts of 42 papers presented at this waste management seminar are included in this volume. Separate abstracts of 27 papers have been prepared for inclusion in the Energy Data Base (EDB). There are 8 papers represented in the proceedings by abstract only and are not included separately in EDB. The subjects covered in these abstracts include: requirements and compliance for the issuance of the second round NPDES permit for the Portsmouth Plant; performance of the pollution abatement facilities at the Portsmouth Plant; the impact of the Kentucky hazardous waste regulations on the Paducah Plant; control of R-114 losses at the gaseous diffusion plants; innovative alternatives to pollution control projects; evaluating the fate and potential radiological impacts of Technetium-99 released to the environment; and technical support interfacing for the FY-1981 line item project control of water pollution and solid wastes at the Paducah Plant. There are 15 other papers which were previously input to the EDB. (RJC)

Proceedings of the 1980 UCC-ND and GAT waste management seminar

International Nuclear Information System (INIS)

1980-12-01

Papers and/or abstracts of 42 papers presented at this waste management seminar are included in this volume. Separate abstracts of 27 papers have been prepared for inclusion in the Energy Data Base (EDB). There are 8 papers represented in the proceedings by abstract only and are not included separately in EDB. The subjects covered in these abstracts include: requirements and compliance for the issuance of the second round NPDES permit for the Portsmouth Plant; performance of the pollution abatement facilities at the Portsmouth Plant; the impact of the Kentucky hazardous waste regulations on the Paducah Plant; control of R-114 losses at the gaseous diffusion plants; innovative alternatives to pollution control projects; evaluating the fate and potential radiological impacts of Technetium-99 released to the environment; and technical support interfacing for the FY-1981 line item project control of water pollution and solid wastes at the Paducah Plant. There are 15 other papers which were previously input to the EDB

Using the Box Complex Method to Optimize Pumping Strategies at the PGDP

Energy Technology Data Exchange (ETDEWEB)

Kopp, Joshua D [Univ of KY, Dept of Civil Engineering

2007-05-01

Over the last several decades numerous hazardous waste sites have taken a heavy toll on the nation's environment. Through the release of toxic chemicals or other pollutant such sites have contaminated either the air, soil, or water beneath them. depending on the type of contaminant, these areas may not be safe for human habitation. Any site that has been contaminated with a hazardous waste and poses a risk to human health or the environment has been classified as a Superfund site by the EPA (EPA 2007) Those sites that pose the greatest environmental risk have been classified as national priority list (NPL) sites, and are eligible for federal clean-up dollars. Of the 15 NPL sites in Kentucky the Paducah Gaseous Diffusion Plant (PGDP) is contaminated the worst. The PGDP is an active uranium enrichment facility located in approximately 10 miles West of Paducah, Kentucky and 3.5 miles south of the Ohio River.

Floodplain/wetland assessment of the effects of construction and operation ofa depleted uranium hexafluoride conversion facility at the Paducah, Kentucky,site.

Energy Technology Data Exchange (ETDEWEB)

Van Lonkhuyzen, R.

2005-09-09

The U.S. Department of Energy (DOE) Depleted Uranium Hexafluoride (DUF{sub 6}) Management Program evaluated alternatives for managing its inventory of DUF{sub 6} and issued the ''Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride'' (DUF{sub 6} PEIS) in April 1999 (DOE 1999). The DUF{sub 6} inventory is stored in cylinders at three DOE sites: Paducah, Kentucky; Portsmouth, Ohio; and East Tennessee Technology Park (ETTP), near Oak Ridge, Tennessee. In the Record of Decision for the DUF{sub 6} PEIS, DOE stated its decision to promptly convert the DUF{sub 6} inventory to a more stable chemical form. Subsequently, the U.S. Congress passed, and the President signed, the ''2002 Supplemental Appropriations Act for Further Recovery from and Response to Terrorist Attacks on the United States'' (Public Law No. 107-206). This law stipulated in part that, within 30 days of enactment, DOE must award a contract for the design, construction, and operation of a DUF{sub 6} conversion plant at the Department's Paducah, Kentucky, and Portsmouth, Ohio, sites, and for the shipment of DUF{sub 6} cylinders stored at ETTP to the Portsmouth site for conversion. This floodplain/wetland assessment has been prepared by DOE, pursuant to Executive Order 11988 (''Floodplain Management''), Executive Order 11990 (Protection of Wetlands), and DOE regulations for implementing these Executive Orders as set forth in Title 10, Part 1022, of the ''Code of Federal Regulations'' (10 CFR Part 1022 [''Compliance with Floodplain and Wetland Environmental Review Requirements'']), to evaluate potential impacts to floodplains and wetlands from the construction and operation of a conversion facility at the DOE Paducah site. Reconstruction of the bridge crossing Bayou Creek would occur within the Bayou Creek 100-year

Trapping technology for gaseous fission products from voloxidation process

Energy Technology Data Exchange (ETDEWEB)

Shin, Jin Myeong; Park, J. J.; Park, G. I.; Jung, I. H.; Lee, H. H.; Kim, G. H.; Yang, M. S

2005-05-15

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, {sup 14}C, Kr, Xe, I and {sup 3}H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and {sup 14}C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion media to HTO for {sup 3}H. This report will be used as a useful means for analyzing the known trapping technologies and help selecting the appropriate trapping methods for trapping volatile and semi-volatile fission products, long-lived fission products, and major heat sources generated from a voloxidation process. It can also be used to design an off-gas treatment system.

Gaseous fuel reactors for power systems

Science.gov (United States)

Kendall, J. S.; Rodgers, R. J.

1977-01-01

Gaseous-fuel nuclear reactors have significant advantages as energy sources for closed-cycle power systems. The advantages arise from the removal of temperature limits associated with conventional reactor fuel elements, the wide variety of methods of extracting energy from fissioning gases, and inherent low fissile and fission product in-core inventory due to continuous fuel reprocessing. Example power cycles and their general performance characteristics are discussed. Efficiencies of gaseous fuel reactor systems are shown to be high with resulting minimal environmental effects. A technical overview of the NASA-funded research program in gaseous fuel reactors is described and results of recent tests of uranium hexafluoride (UF6)-fueled critical assemblies are presented.

Innovative vitrification for soil remediation

International Nuclear Information System (INIS)

Jetta, N.W.; Patten, J.S.; Hart, J.G.

1995-01-01

The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS trademark) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase 1 consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project. During Phase 2, the basic nitrification process design was modified to meet the specific needs of the new waste streams available at Paducah. The system design developed for Paducah has significantly enhanced the processing capabilities of the Vortec vitrification process. The overall system design now includes the capability to shred entire drums and drum packs containing mud, concrete, plastics and PCB's as well as bulk waste materials. This enhanced processing capability will substantially expand the total DOE waste remediation applications of the technology

Gaseous phase heat capacity of benzoic acid

NARCIS (Netherlands)

Santos, L.M.N.B.F.; Alves da Rocha, M.A.; Gomes, L.R.; Schröder, B.; Coutinho, J.A.P.

2010-01-01

The gaseous phase heat capacity of benzoic acid (BA) was proven using the experimental technique called the "in vacuum sublimation/vaporization Calvet microcalorimetry drop method". To overcome known experimental shortfalls, the gaseous phase heat capacity of BA monomer was estimated by ab initio

Unraveling the evolving nature of gaseous and dissolved carbon dioxide in champagne wines: a state-of-the-art review, from the bottle to the tasting glass.

Science.gov (United States)

Liger-Belair, Gérard; Polidori, Guillaume; Zéninari, Virginie

2012-06-30

In champagne and sparkling wine tasting, the concentration of dissolved CO(2) is indeed an analytical parameter of high importance since it directly impacts the four following sensory properties: (i) the frequency of bubble formation in the glass, (ii) the growth rate of rising bubbles, (iii) the mouth feel, and (iv) the nose of champagne, i.e., its so-called bouquet. In this state-of-the-art review, the evolving nature of the dissolved and gaseous CO(2) found in champagne wines is evidenced, from the bottle to the glass, through various analytical techniques. Results obtained concerning various steps where the CO(2) molecule plays a role (from its ingestion in the liquid phase during the fermentation process to its progressive release in the headspace above the tasting glass) are gathered and synthesized to propose a self-consistent and global overview of how gaseous and dissolved CO(2) impact champagne and sparkling wine science. Copyright © 2011 Elsevier B.V. All rights reserved.

Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Taylor, F. G.; Hanna, S. R.; Parr, P. D.

1978-12-01

The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified with concentrations in plant materials (fescue grass) decreasing with increasing distance from the cooling tower. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. Results suggest that differences in retention in litter and foliage are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil-water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Preliminary model estimates of drift deposition are compared to deposition measurements.

Process for exchanging hydrogen isotopes between gaseous hydrogen and water

International Nuclear Information System (INIS)

Hindin, S. G.; Roberts, G. W.

1980-01-01

A process for exchanging isotopes of hydrogen, particularly tritium, between gaseous hydrogen and water is provided whereby gaseous hydrogen depeleted in tritium and liquid or gaseous water containing tritium are reacted in the presence of a metallic catalyst

Influence of a gaseous atmosphere on fatigue crack propagation

International Nuclear Information System (INIS)

Henaff, G.

2002-01-01

The paper presents a review of the current knowledge on the influence of gaseous atmospheres, and primarily ambient air, on fatigue crack propagation in metallic alloys. Experimental evidence of the effect of exposure to ambient air or any moist environment on fatigue crack propagation in steels is first proposed. The different interacting processes are analyzed so as to clearly uncouple the influence of the various factors on crack growth resistance. Two distinct mechanisms are identified: the adsorption of vapour molecules and hydrogen assisted fracture at crack tip. (author)

Methods for reformation of gaseous hydrocarbons using electrical discharge

KAUST Repository

Cha, Min Suk

2017-02-16

Methods for the reformation of gaseous hydrocarbons are provided. The methods can include forming a bubble containing the gaseous hydrocarbon in a liquid. The bubble can be generated to pass in a gap between a pair of electrodes, whereby an electrical discharge is generated in the bubble at the gap between the electrodes. The electrodes can be a metal or metal alloy with a high melting point so they can sustain high voltages of up to about 200 kilovolts. The gaseous hydrocarbon can be combined with an additive gas such as molecular oxygen or carbon dioxide. The reformation of the gaseous hydrocarbon can produce mixtures containing one or more of H2, CO, H2O, CO2, and a lower hydrocarbon such as ethane or ethylene. The reformation of the gaseous hydrocarbon can produce low amounts of CO2 and H2O, e.g. about 15 mol-% or less.

Methods for reformation of gaseous hydrocarbons using electrical discharge

KAUST Repository

Cha, Min; Zhang, Xuming

2017-01-01

Methods for the reformation of gaseous hydrocarbons are provided. The methods can include forming a bubble containing the gaseous hydrocarbon in a liquid. The bubble can be generated to pass in a gap between a pair of electrodes, whereby an electrical discharge is generated in the bubble at the gap between the electrodes. The electrodes can be a metal or metal alloy with a high melting point so they can sustain high voltages of up to about 200 kilovolts. The gaseous hydrocarbon can be combined with an additive gas such as molecular oxygen or carbon dioxide. The reformation of the gaseous hydrocarbon can produce mixtures containing one or more of H2, CO, H2O, CO2, and a lower hydrocarbon such as ethane or ethylene. The reformation of the gaseous hydrocarbon can produce low amounts of CO2 and H2O, e.g. about 15 mol-% or less.

Martin Marietta Energy Systems Environmental Management Plan, FY 1985-1989

International Nuclear Information System (INIS)

Furth, W.F.; Cowser, K.E.; Jones, C.G.; Mitchell, M.E.; Perry, T.P.A.; Stair, C.L.; Stinton, L.H.

1985-05-01

This plan contains the most recent revisions (as of April 1, 1985) identifying and resolving environmental problems during the next five years at the four installations managed for DOE by Martin Marietta Energy Systems, Inc. (Energy Systems). These installations are Oak Ridge National Laboratory (ORNL), Oak Ridge Gaseous Diffusion Plant (ORGDP), Oak Ridge Y-12 Plant (Y-12), and Paducah Gaseous Diffusion Plant (PGDP). The report is not an exhaustive catalogue of environmental programs for which funds will be or have been requested. The thrust is to categorize the environmental challenges by the nature of the challenge. The challenges are identified by categories: (1) radioactive waste, (2) hazardous waste, (3) co-contaminated waste (hazardous and radioactive contaminated), (4) conventional waste, (5) monitoring, and (6) remedial actions and decommissioning

Martin Marietta Energy Systems Environmental Management Plan, FY 1985-1989

Energy Technology Data Exchange (ETDEWEB)

Furth, W.F.; Cowser, K.E.; Jones, C.G.; Mitchell, M.E.; Perry, T.P.A.; Stair, C.L.; Stinton, L.H.

1985-05-01

This plan contains the most recent revisions (as of April 1, 1985) identifying and resolving environmental problems during the next five years at the four installations managed for DOE by Martin Marietta Energy Systems, Inc. (Energy Systems). These installations are Oak Ridge National Laboratory (ORNL), Oak Ridge Gaseous Diffusion Plant (ORGDP), Oak Ridge Y-12 Plant (Y-12), and Paducah Gaseous Diffusion Plant (PGDP). The report is not an exhaustive catalogue of environmental programs for which funds will be or have been requested. The thrust is to categorize the environmental challenges by the nature of the challenge. The challenges are identified by categories: (1) radioactive waste, (2) hazardous waste, (3) co-contaminated waste (hazardous and radioactive contaminated), (4) conventional waste, (5) monitoring, and (6) remedial actions and decommissioning.

A Thermodynamic History of the Solar Constitution — I: The Journey to a Gaseous Sun

Directory of Open Access Journals (Sweden)

Robitaille P.-M.

2011-07-01

Full Text Available History has the power to expose the origin and evolution of scientific ideas. How did humanity come to visualize the Sun as a gaseous plasma? Why is its interior thought to contain blackbody radiation? Who were the first people to postulate that the density of the solar body varied greatly with depth? When did mankind first conceive that the solar surface was merely an illusion? What were the foundations of such thoughts? In this regard, a detailed review of the Sun’s thermodynamic history provides both a necessary exposition of the circumstance which accompanied the acceptance of the gaseous mod- els and a sound basis for discussing modern solar theories. It also becomes an invitation to reconsider the phase of the photosphere. As such, in this work, the contributions of Pierre Simon Laplace, Alexander Wilson, William Herschel, Hermann von Helmholtz, Herbert Spencer, Richard Christopher Carrington, John Frederick William Herschel, Father Pietro Angelo Secchi, Herv ́ e August Etienne Albans Faye, Edward Frankland, Joseph Norman Lockyer, Warren de la Rue, Balfour Stewart, Benjamin Loewy, and Gustav Robert Kirchhoff, relative to the evolution of modern stellar models, will be discussed. Six great pillars created a gaseous Sun: 1 Laplace’s Nebular Hypothesis, 2 Helmholtz’ contraction theory of energy production, 3 Andrew’s elucidation of crit- ical temperatures, 4 Kirchhoff’s formulation of his law of thermal emission, 5 Pl ̈ ucker and Hittorf’s discovery of pressure broadening in gases, and 6 the evolution of the stel- lar equations of state. As these are reviewed, this work will venture to highlight not only the genesis of these revolutionary ideas, but also the forces which drove great men to advance a gaseous Sun.

Strong motion modeling at the Paducah Diffusion Facility for a large New Madrid earthquake

International Nuclear Information System (INIS)

Herrmann, R.B.

1991-01-01

The Paducah Diffusion Facility is within 80 kilometers of the location of the very large New Madrid earthquakes which occurred during the winter of 1811-1812. Because of their size, seismic moment of 2.0 x 10 27 dyne-cm or moment magnitude M w = 7.5, the possible recurrence of these earthquakes is a major element in the assessment of seismic hazard at the facility. Probabilistic hazard analysis can provide uniform hazard response spectra estimates for structure evaluation, but a deterministic modeling of a such a large earthquake can provide strong constraints on the expected duration of motion. The large earthquake is modeled by specifying the earthquake fault and its orientation with respect to the site, and by specifying the rupture process. Synthetic time histories, based on forward modeling of the wavefield, from each subelement are combined to yield a three component time history at the site. Various simulations are performed to sufficiently exercise possible spatial and temporal distributions of energy release on the fault. Preliminary results demonstrate the sensitivity of the method to various assumptions, and also indicate strongly that the total duration of ground motion at the site is controlled primarily by the length of the rupture process on the fault

Waste and cost reduction using dual wall reverse circulation drilling with multi-level groundwater sampling for contaminant plume delineation

International Nuclear Information System (INIS)

Smuin, D.R.

1995-01-01

This paper describes the drilling and sampling methods used to delineate a groundwater contaminant plume at the Paducah Gaseous Diffusion Plant (PGDP) during the Groundwater Monitoring IV characterization. The project was unique in that it relied upon dual wall reverse circulation drilling instead of the traditional hollow stem auger method. The Groundwater Monitoring program sought to characterize the boundaries, both vertically and horizontally, of the northeast plume which contains both 99 Tc and trichloroethene. This paper discusses the strengths and weaknesses of the drilling method used by investigators

Process for exchanging hydrogen isotopes between gaseous hydrogen and water

International Nuclear Information System (INIS)

Hindin, S.G.; Roberts, G.W.

1977-01-01

A process is described for exchanging isotopes (particularly tritium) between water and gaseous hydrogen. Isotope depleted gaseous hydrogen and water containing a hydrogen isotope are introduced into the vapour phase in a first reaction area. The steam and gaseous hydrogen are brought into contact with a supported metal catalyst in this area in a parallel flow at a temperature range of around 225 and 300 0 C. An effluent flow comprising a mixture of isotope enriched gaseous hydrogen and depleted steam is evacuated from this area and the steam condensed into liquid water [fr

Absorbing method of iodine in radioactive gaseous wastes

International Nuclear Information System (INIS)

Fukutome, Yutaka; Mifuji, Hiroshi; Ito, Sakae.

1983-01-01

Purpose: To maintain an iodine adsorbing efficiency at a high level by keeping the adsorbing atmosphere to more than a predetermined temperature to thereby suppress the degradation and the activity reduction in zeolite. Method: Adsorption and desorption-regeneration of gaseous wastes are performed in parallel by heating gaseous wastes in a heater and switchingly supplying the same to adsorption columns by way of valve operation. Processed gases are cooled in a cooler and desorbed gases are supplied to an after-treatment device to eliminate or recover iodine 131. In the adsorption column, iodine in gaseous wastes is adsorbed to remove by using zeolite, wherein the adsorbing atmosphere is kept at a temperature higher than 40 0 C. This can prevent the formation of an aqueous HNO 3 solution from NO 2 and H 2 O contained in the gaseous wastes and prevent the degradation of the zeolite adsorption layer. (Kawakami, Y.)

Radiation protection with consumer products containing gaseous tritium light sources

International Nuclear Information System (INIS)

Rahders, Erio; Haeusler, Uwe

2017-01-01

Consumer products containing gaseous tritium light sources (GTLS) were examined with respect to their radiological safety potential regarding leak tightness or accidents. The maximum tritium leakage rate of 2.7 Bq/d determined from experimental testing is well below the criterion for leak tightness of sealed radioactive sources in DIN 25426-4. In order to investigate the incorporation of tritium due to contact with consumer products, 2 scenarios were reviewed; the correct use of a tritium watch and the accident scenario with a keyring.

Gaseous Electronics Tables, Atoms, and Molecules

CERN Document Server

Raju, Gorur Govinda

2011-01-01

With the constant emergence of new research and application possibilities, gaseous electronics is more important than ever in disciplines including engineering (electrical, power, mechanical, electronics, and environmental), physics, and electronics. The first resource of its kind, Gaseous Electronics: Tables, Atoms, and Molecules fulfills the author's vision of a stand-alone reference to condense 100 years of research on electron-neutral collision data into one easily searchable volume. It presents most--if not all--of the properly classified experimental results that scientists, researchers,

Precision tracking with a single gaseous pixel detector

NARCIS (Netherlands)

Tsigaridas, S.; van Bakel, N.; Bilevych, Y.; Gromov, V.; Hartjes, F.; Hessey, N.P.; de Jong, P.; Kluit, R.

2015-01-01

The importance of micro-pattern gaseous detectors has grown over the past few years after successful usage in a large number of applications in physics experiments and medicine. We develop gaseous pixel detectors using micromegas-based amplification structures on top of CMOS pixel readout chips.

Gaseous distention of the hypopharynx and cervical esophagus with nasal CPAP: a mimicker of pharyngeal perforation and esophageal atresia

Energy Technology Data Exchange (ETDEWEB)

Walor, David; Berdon, Walter; Holt, Peter D.; Fox, Matthew [Columbia University Medical Center, Department of Radiology, New York, NY (United States); Children' s Hospital of New York, New York, NY (United States); Anderson, Nicole [Columbia University Medical Center, Department of Neonatology, New York, NY (United States); Children' s Hospital of New York, New York, NY (United States)

2005-12-01

Nasal continuous positive airway pressure (CPAP) has been used since 1975 as the initial treatment for respiratory distress syndrome (RDS) in very premature infants. Gaseous distention of the abdomen (CPAP belly) is a common secondary effect of CPAP. Gaseous distention of the hypopharynx is also common. To determine the incidence of hypopharyngeal distention in infants on CPAP. We performed a retrospective review of the chest radiographs of 57 premature infants treated with CPAP during a 4-week period to find the presence and degree of hypopharyngeal distention. Of the 57 radiographs, 14 (25%) revealed gaseous distention of the hypopharynx and/or cervical esophagus. On occasion, this raised concern for pharyngeal perforation or esophageal atresia. Awareness that CPAP-related hypopharyngeal distention is common should help radiologists avoid erroneous consideration of esophageal atresia or hypopharyngeal perforation. (orig.)

Gaseous distention of the hypopharynx and cervical esophagus with nasal CPAP: a mimicker of pharyngeal perforation and esophageal atresia

International Nuclear Information System (INIS)

Walor, David; Berdon, Walter; Holt, Peter D.; Fox, Matthew; Anderson, Nicole

2005-01-01

Nasal continuous positive airway pressure (CPAP) has been used since 1975 as the initial treatment for respiratory distress syndrome (RDS) in very premature infants. Gaseous distention of the abdomen (CPAP belly) is a common secondary effect of CPAP. Gaseous distention of the hypopharynx is also common. To determine the incidence of hypopharyngeal distention in infants on CPAP. We performed a retrospective review of the chest radiographs of 57 premature infants treated with CPAP during a 4-week period to find the presence and degree of hypopharyngeal distention. Of the 57 radiographs, 14 (25%) revealed gaseous distention of the hypopharynx and/or cervical esophagus. On occasion, this raised concern for pharyngeal perforation or esophageal atresia. Awareness that CPAP-related hypopharyngeal distention is common should help radiologists avoid erroneous consideration of esophageal atresia or hypopharyngeal perforation. (orig.)

Recent Advances in the Characterization of Gaseous and Liquid Fuels by Vibrational Spectroscopy

Directory of Open Access Journals (Sweden)

Johannes Kiefer

2015-04-01

Full Text Available Most commercial gaseous and liquid fuels are mixtures of multiple chemical compounds. In recent years, these mixtures became even more complicated when the suppliers started to admix biofuels into the petrochemical basic fuels. As the properties of such mixtures can vary with composition, there is a need for reliable analytical technologies in order to ensure stable operation of devices such as internal combustion engines and gas turbines. Vibrational spectroscopic methods have proved their suitability for fuel characterization. Moreover, they have the potential to overcome existing limitations of established technologies, because they are fast and accurate, and they do not require sampling; hence they can be deployed as inline sensors. This article reviews the recent advances of vibrational spectroscopy in terms of infrared absorption (IR and Raman spectroscopy in the context of fuel characterization. The focus of the paper lies on gaseous and liquid fuels, which are dominant in the transportation sector and in the distributed generation of power. On top of an introduction to the physical principles and review of the literature, the techniques are critically discussed and compared with each other.

Entrapment process of radioactive gaseous wastes

International Nuclear Information System (INIS)

Gagneraud, Francis; Gagneraud, Michel.

1981-01-01

Process for collecting chemically inert gaseous radioactive waste in melted substances, whereby the gaseous waste is injected under pressure in a molten substance to its saturation point followed by fast cooling. This substance is constituted of glass, ceramics, metallurgical drosses and slag masses in fusion. Its cooling is carried out by quenching by means of running water or a gas fluid, or by casting into vessels with great thermal inertia such as cast iron or similar, before recovery and confinement in receptacles for storage [fr

Behaviour of radioiodine in gaseous effluents

International Nuclear Information System (INIS)

Barry, P.J.

1968-01-01

Because of the different chemical forms in which radioiodine occurs in the gaseous state, it is important when designing efficient filters to know the chemical forms which may be present in the effluent gases when various operations are being carried out and to know the effect of different gaseous environments on the filtration efficiency. To obtain this information it is necessary to have available reliable means of characterizing different chemical forms and to sample gaseous effluents when these operations are being carried out. This paper describes the use for identifying molecular iodine of metallic screens in a multi-component sampling pack in different gaseous environments. Using multi-component sampling packs, the fractionation of iodine nuclides between different chemical forms was measured in the effluent gases escaping from an in-pile test loop in which the fuel was deliberately ruptured by restricting the flow of coolant. Sequential samples were taken for six hours after the rupture and it was possible to follow during this period the individual behaviours of 13 '1I, 133 I and 135 I. Simultaneous samples were also obtained of the noble gases in the effluent gas stream and of the iodine nuclides in the loop coolant. Similar experiments have been carried out with a view to characterizing the different chemical behaviour of radioiodine as it is released from a variety of operations in the nuclear industry including the cutting of fuel sections in metallurgical examination caves and an incinerator. (author)

IAEA decadal activities in the field of radioactive gaseous waste management

International Nuclear Information System (INIS)

Plumb, G.R.

1991-01-01

The IAEA has long recognized that gaseous waste management is vital in the design and safe operation of all nuclear facilities such that in the decade of the 1980's the IAEA program covered the important aspects of the entire field. The activities reviewed in this paper were marked at the outset by a comprehensive international symposium on the subject in February 1980 organized by the IAEA jointly with the Nuclear Energy Agency of the OECD when the detailed state-of-the-art was established in 43 papers. In the interim, experts have been convened in IAEA sponsored meetings to result in sixteen technical documents which included summaries of three substantial Co-ordinated Research Programs. Early IAEA activities paid particular attention to management of gas radionuclides which from a matured nuclear industry, could be judged to build-up to long-term sources of irradiation for regional and global populations. Mid-term ongoing activities in handling and retention of gaseous radionuclides arising from abnormal operations in nuclear power plants were given much emphasis following the Chernobyl accident. In the latter years the IAEA activities included detailed examinations of the design and operation of gas cleaning systems for the range of nuclear facilities. Technical reports on gaseous waste management were issued relating to high-level liquid waste conditioning plants (including control of semi-volatiles), nuclear power plants, low- and intermediate-level radioactive materials handling facilities and radioactive waste incinerators

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices

International Nuclear Information System (INIS)

1977-09-01

Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant

Microbial production of gaseous hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Fukuda, Hideo

1987-10-20

Microbial production of ethylene, isobutane and a saturated gaseous hydrocarbon mixture was described. Microbial ethylene production was studied with Penicillium digitatum IFO 9372 and a novel pathway of the ethylene biosynthesis through alpha-ketoglutarate was proposed. Rhodotorula minuta IFO 1102 was selected for the microbial production of isobutane and the interesting actions of L-leucine and L-phenylalanine for the isobutane production were found. It was finally presented about the microbial production of a saturated gaseous hydrocarbon mixture with Rhizopus japonicus IFO 4758 was described. A gas mixture was produced through a chemical reaction of SH compounds and some cellular component such as squalene under aerobic conditions. (4 figs, 7 tabs, 41 refs)

Gaseous emissions from coal stockpiles

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-01-15

Stockpiled coal undergoes atmospheric oxidation and desorption processes during open air storage. These processes release gases to the environment which may effect health and safety by their toxicity and flammability. In extreme cases, this could lead to a fire. This report discusses gaseous emissions from coal stockpiles. It covers gas emission mechanisms, and gas sampling and testing methods, before examining in more detail the principal gases that have been emitted. It concludes that there is limited research in this area and more data are needed to evaluate the risks of gaseous emissions. Some methods used to prevent coal self-heating and spontaneous combustion can be applied to reduce emissions from coal stockpiles.

Applicability of federal and state environmental requirements to selected DOE field installations and recommendations for development of generic compliance guidance. Final report

International Nuclear Information System (INIS)

1982-01-01

This final report identifies and describes federal and state environmental requirements applicable to selected Department of Energy (DOE) nuclear field installations, establishes priorities for the requirements, determines the need for development of additional compliance guidance, and recommends development of compliance guidance for specific priority requirements. Compliance guidance developed as part of the study is summarized. The applicability of environmental requirements to 12 DOE field installations was reviewed. Five installations were examined under Task 4. They are: Nevada Test Site; Lawrence Berkeley Laboratory; Paducah Gaseous Diffusion Plant; Oak Ridge Y-12 Plant; and Los Alamos Scientific Laboratory. Seven other installations were reviewed under Task 2 and included: Idaho National Engineering Laboratory; Hanford; Savannah River Plant; Oak Ridge Gaseous Diffusion Plant; Pantex Plant; Rocky Flats Plant; and Lawrence Livermore Laboratory. This report combines results of the two tasks. The objective of the study was to identify the set of environmental requirements which are applicable to DOE field installations, track changes in the requirements, and prepare compliance guidance for important requirements and important regulatory developments as necessary. A cumulative calendar update for July 1982 represents the current status of applicable requirements. Environmental profiles of each facility, along with ambient monitoring results, are presented. Applicable federal requirements are identified. The specific applicability of federal and state requirements is detailed for each installation. Compliance guidance available from various agencies is described. Each requirement described is ranked by priority, and recommendations are made for development of additional guidance

US Department of Energy interim mixed waste inventory report: Waste streams, treatment capacities and technologies: Volume 3, Site specific---Illinois through New York

International Nuclear Information System (INIS)

1993-04-01

The Department of Energy (DOE) has prepared this report to provide an inventory of its mixed wastes and treatment capacities and technologies in response to Section 105(a) of the Federal Facility Compliance act (FFCAct) of 1992 (Pub. L. No. 102-386). As required by the FFCAct-1992, this report provides site-specific information on DOE's mixed waste streams and a general review of available and planned treatment facilities for mixed wastes for the following sites: Argonne National Laboratory-East; Site A/plot M in Palos Forest Preserve, Illinois; Ames Laboratory; Paducah Gaseous Diffusion Plant; Portsmouth Naval Shipyard; Kansas City Plant; University of Missouri; Weldon Springs Site, St. Charles, Missouri; Nevada Test Site; Middlesex Sampling Plant, Middlesex, New Jersey; Princeton Plasma Physics Laboratory; LANL; Sandia national laboratory; Brookhaven National Laboratory; Colonie Interim Storage Site, Colonie, New York; Knolls Atomic Power Laboratory; Knolls Atomic Power Laboratory-Kesselring Site; and West Valley Demonstration Project

Technology needs for environmental restoration remedial action. Environmental Restoration Program

Energy Technology Data Exchange (ETDEWEB)

Watson, J.S.

1992-11-01

This report summarizes the current view of the most important technology needs for the US Department of Energy (DOE) facilities operated by Martin Marietta Energy Systems, Inc. These facilities are the Oak Ridge National Laboratory, the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, the Paducah Gaseous Diffusion Plant, and the Portsmouth Gaseous Diffusion Plant. The sources of information used in this assessment were a survey of selected representatives of the Environmental Restoration (ER) programs at each facility, results from a questionnaire distributed by Geotech CWM, Inc., for DOE, and associated discussions with individuals from each facility. This is not a final assessment, but a brief look at an ongoing assessment; the needs will change as the plans for restoration change and, it is hoped, as some technical problems are solved through successful development programs.

Technology needs for environmental restoration remedial action

Energy Technology Data Exchange (ETDEWEB)

Watson, J.S.

1992-11-01

This report summarizes the current view of the most important technology needs for the US Department of Energy (DOE) facilities operated by Martin Marietta Energy Systems, Inc. These facilities are the Oak Ridge National Laboratory, the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, the Paducah Gaseous Diffusion Plant, and the Portsmouth Gaseous Diffusion Plant. The sources of information used in this assessment were a survey of selected representatives of the Environmental Restoration (ER) programs at each facility, results from a questionnaire distributed by Geotech CWM, Inc., for DOE, and associated discussions with individuals from each facility. This is not a final assessment, but a brief look at an ongoing assessment; the needs will change as the plans for restoration change and, it is hoped, as some technical problems are solved through successful development programs.

Technology needs for environmental restoration remedial action

International Nuclear Information System (INIS)

Watson, J.S.

1992-11-01

This report summarizes the current view of the most important technology needs for the US Department of Energy (DOE) facilities operated by Martin Marietta Energy Systems, Inc. These facilities are the Oak Ridge National Laboratory, the Oak Ridge K-25 Site, the Oak Ridge Y-12 Plant, the Paducah Gaseous Diffusion Plant, and the Portsmouth Gaseous Diffusion Plant. The sources of information used in this assessment were a survey of selected representatives of the Environmental Restoration (ER) programs at each facility, results from a questionnaire distributed by Geotech CWM, Inc., for DOE, and associated discussions with individuals from each facility. This is not a final assessment, but a brief look at an ongoing assessment; the needs will change as the plans for restoration change and, it is hoped, as some technical problems are solved through successful development programs

Engineering design of the Aries-IV gaseous divertor

International Nuclear Information System (INIS)

Hasan, M.Z.; Najmabadi, F.; Sharafat, S.

1994-01-01

ARIES-IV is a conceptual, D-T burning, steady-state tokamak fusion reactor producing 1000 MWe net. It operates in the second plasma stability regime. The structural material is SiC composite and the primary coolant is helium at 10MPa base pressure. ARIES-IV uses double-null divertors for particle control. Total thermal power recovered from the divertors is 425MW, which is 16% of the total reactor thermal power. Among the desirable goals of divertor design were to avoid the use of tungsten and to use the same structural material and primary coolant as in the blanket design. In order to reduce peak heat flux, the innovative gaseous divertor has been used in ARIES-IV. A gaseous divertor reduces peak heat flux by increasing the surface area and by distributing particle and radiation energy more uniformly. Another benefit of gaseous divertor is the reduction of plasma temperature in the divertor chamber, so that material erosion due to sputtering, can be diminished. This makes the use of low-Z material possible in a gaseous divertor

Report on the Watershed Monitoring Program at the Paducah Site January-December 1998

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A.; Peterson, M.J.; Ryon, M.G.; Southworth, G.R.

1999-03-01

Watershed Monitoring of Big Bayou and Little Bayou creeks has been conducted since 1987. The monitoring was conducted by the University of Kentucky between 1987 and 1991 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 to present. The goals of monitoring are to (1) demonstrate that the effluent limitations established for DOE protect and maintain the use of Little Bayour and Big Bayou creeks for frowth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, and (3) document the effects of pollution abatement facilities on stream biota. The watershed (biological) monitoring discussed in this report was conducted under DOE Order 5400.1, General Environmental Protection Program. Future monitoring will be conducted as required by the Kentucky Pollutant Discharge Elimination System (KPDES) permit issued to the Department of Energy (DOE) in March 1998. A draft Watershed Monitoring Program plan was approved by the Kentucky Division of Water and will be finalized in 1999. The DOE permit also requires toxicity monitoring of one continuous outfall and of three intermittent outfalls on a quarterly basis. The Watershed Monitoring Program for the Paducah Site during calendar year 1998 consisted of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of fish communities. This report focuses on ESD activities occurring from january 1998 to December 1998, although activities conducted outside this time period are included as appropriate.

Growth of graphene films from non-gaseous carbon sources

Science.gov (United States)

Tour, James; Sun, Zhengzong; Yan, Zheng; Ruan, Gedeng; Peng, Zhiwei

2015-08-04

In various embodiments, the present disclosure provides methods of forming graphene films by: (1) depositing a non-gaseous carbon source onto a catalyst surface; (2) exposing the non-gaseous carbon source to at least one gas with a flow rate; and (3) initiating the conversion of the non-gaseous carbon source to the graphene film, where the thickness of the graphene film is controllable by the gas flow rate. Additional embodiments of the present disclosure pertain to graphene films made in accordance with the methods of the present disclosure.

Flux and polarization signals of spatially inhomogeneous gaseous exoplanets

NARCIS (Netherlands)

Karalidi, T.; Stam, D.M.; Guirado, D.

2013-01-01

Aims. We present numerically calculated, disk-integrated, spectropolarimetric signals of starlight that is reflected by vertically and horizontally inhomogeneous gaseous exoplanets. We include various spatial features that are present on Solar System’s gaseous planets: belts and zones, cyclonic

Summary and Outlook of the International Workshop on Aging Phenomena in Gaseous Detectors (DESY, Hamburg, October, 2001)

CERN Document Server

Titov, M L; Padilla, C; Tesch, N

2002-01-01

High Energy Physics experiments are currently entering a new era which requires the operation of gaseous particle detectors at unprecedented high rates and integrated particle fluxes. Full functionality of such detectors over the lifetime of an experiment in a harsh radiation environment is of prime concern to the involved experimenters. New classes of gaseous detectors such as large-scale straw-type detectors, Micro-pattern Gas Detectors and related detector types with their own specific aging effects have evolved since the first workshop on wire chamber aging was held at LBL, Berkeley in 1986. In light of these developments and as detector aging is a notoriously complex field, the goal of the workshop was to provide a forum for interested experimentalists to review the progress in understanding of aging effects and to exchange recent experiences. A brief summary of the main results and experiences reported at the 2001 workshop is presented, with the goal of providing a systematic review of aging effects in ...

Uranium enrichment by the gaseous diffusion process

International Nuclear Information System (INIS)

Petit, J.F.

1977-01-01

After a brief description of the process and technology (principle, stage constitution, cascade constitution, and description of a plant), the author gives the history of gaseous diffusion and describes the existing facilities. Among the different enrichment processes contemplated in the USA during and after the last world war, gaseous diffusion has been the only one to be developed industrially on a wide scale in the USA, then in the UK, in the USSR and in France. The large existing capacities in the USA provided the country with a good starting base for the development of a light-water nuclear power plant programme, the success of which led to a shortfall in production means. France and the USA, possessing the necessary know-how, have been able to undertake the realization of two industrial programmes: the CIP-CUP programme in the USA and the Eurodif project in France. Current plans still call for the construction of several plants by 1990. Can the gaseous diffusion process meet this challenge. Technically, there is no doubt about it. Economically, this process is mainly characterized by large energy consumption and the necessity to build large plants. This leads to a large investment, at least for the first plant. Other processes have been developed with a view to reducing both energy and capital needs. However, in spite of continuous studies and technological progress, no process has yet proved competitive. Large increments in capacities are still expected to come from gaseous diffusion, and several projects taking into account the improvements in flexibility, automatization, reliability and reduced investment, are analysed in the paper. Combining new facilities with existing plants has already proved to be of great interest. This situation explains why gaseous diffusion is being further investigated and new processes are being studied. (author)

Program management: The keys to a successful ERWM contract

International Nuclear Information System (INIS)

Lenyk, R.G.; Cusack, J.G.

1995-01-01

Program management for a large Environmental Restoration and Waste Management (ERWM) task order contract is both a skill and an art. Unlike project management, program management deals with global and political issues, with both client and home organizations, as well as with day-to-day operations. Program management requires up-front planning and nurturing, for no contract matures successfully by itself. This paper identifies the many opportunities presented in the planning and initial implementation of the contract. Potential traps are identified so that they can be recognized and avoided or mitigated. Teaming and subcontracting are also addressed. The authors rely on years of program management experience to explore such questions as the following: Can you have an integrated team? What needs to be done before you sign Your contract? Do you know who your client(s) is(are)? Have you incorporated the relevant, especially any new, procurement strategies? The US Department of Energy-Oak Ridge Operations (DOE-ORO) ERWM Remedial Design Contract with Foster Wheeler Environmental Corporation is used as a model for exploring these topics. This ERWM Program-which focuses on the Oak Ridge National Laboratory, the Y-12 Weapons Plant, and the K-25 Site in Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant in Paducah, Kentucky; and the Portsmouth Gaseous Diffusion Plant in Portsmouth, Ohio-is in its fifth year with over 225 task orders. The program has been highly successful and has obtained from DOE outstanding marks for achieving quality, responsiveness, timeliness, and subcontracting goals

Radioactivity in gaseous waste discharged from the separations facilities during 1978

International Nuclear Information System (INIS)

Anderson, J.D.; Poremba, B.E.

1979-01-01

This document is issued quarterly for the purpose of summarizing the radioactive gaseous wastes that are discharged from the facilities of the Rockwell Hanford Operations. Data on alpha and beta emissions during 1978 are presented where relevant to the gaseous effluent. Emission data are not included on gaseous wastes produced within the 200 Areas by other Hanford contractors

Generation of gaseous tritium standards

International Nuclear Information System (INIS)

Hohorst, F.A.

1994-09-01

The determination of aqueous and non-aqueous tritium in gaseous samples is one type of determination often requested of radioanalytical laboratories. This determination can be made by introducing the sample as a gas into a sampling train containing two silica gel beds separated by.a catalytic oxidizer bed. The first bed traps tritiated water. The sample then passes into and through the oxidizer bed where non-aqueous tritium containing species are oxidized to water and other products of combustion. The second silica gel bed then traps the newly formed tritiated water. Subsequently, silica gel is removed to plastic bottles, deionized water is added, and the mixture is permitted to equilibrate. The tritium content of the equilibrium mixture is then determined by conventional liquid scintillation counting (LSC). For many years, the moisture content of inert, gaseous samples has been determined using monitors which quantitatively electrolyze the moisture present after that moisture has been absorbed by phosphorous pentoxide or other absorbents. The electrochemical reaction is quantitative and definitive, and the energy consumed during electrolysis forms the basis of the continuous display of the moisture present. This report discusses the experimental evaluation of such a monitor as the basis for a technique for conversion of small quantities of SRMs of tritiated water ( 3 HOH) into gaseous tritium standards ( 3 HH)

Martin Marietta Energy Systems, Inc., Groundwater Program Management Plan

International Nuclear Information System (INIS)

Early, T.O.

1994-05-01

The purpose of the Martin Marietta Energy Systems, Inc., (Energy Systems) Groundwater Program Management Plan is to define the function, organizational structure (including associated matrix organizations), interfaces, roles and responsibilities, authority, and relationship to the Department of Energy for the Energy Systems Groundwater Program Office (GWPO). GWPO is charged with the responsibility of coordinating all components of the groundwater program for Energy Systems. This mandate includes activities at the three Oak Ridge facilities [Oak Ridge National Laboratory, the Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site], as well as the Paducah and Portsmouth Gaseous Diffusion Plants

Martin Marietta Energy Systems, Inc., Groundwater Program Management Plan

Energy Technology Data Exchange (ETDEWEB)

Early, T.O.

1994-05-01

The purpose of the Martin Marietta Energy Systems, Inc., (Energy Systems) Groundwater Program Management Plan is to define the function, organizational structure (including associated matrix organizations), interfaces, roles and responsibilities, authority, and relationship to the Department of Energy for the Energy Systems Groundwater Program Office (GWPO). GWPO is charged with the responsibility of coordinating all components of the groundwater program for Energy Systems. This mandate includes activities at the three Oak Ridge facilities [Oak Ridge National Laboratory, the Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site], as well as the Paducah and Portsmouth Gaseous Diffusion Plants.

Review on the effects of dual-fuel operation, using diesel and gaseous fuels, on emissions and performance

NARCIS (Netherlands)

Wagemakers, A.M.L.M.; Leermakers, C.A.J.

2012-01-01

In recent years the automotive industry has been forced to reduce the harmful and pollutant emissions emitted by direct injected diesel engines. To accomplish this difficult task various solutions have been proposed. One of these proposed solutions is the usage of gaseous fuels in addition to the

Legal provisions governing gaseous effluents radiological monitoring

International Nuclear Information System (INIS)

Winkelmann, I.

1985-01-01

This contribution explains the main provisions governing radiological monitoring of gaseous effluents from LWR type nuclear power plants. KTA rule 1503.1 defines the measuring methods and tasks to be fulfilled by reactor operators in order to safeguard due monitoring and accounting of radioactive substances in the plants' gaseous effluents. The routine measurements are checked by a supervisory programme by an independent expert. The routine controls include analysis of filter samples, comparative measurement of radioactive noble gases, interlaboratory comparisons, and comparative evaluation of measured values. (DG) [de

Gaseous waste processing device in nuclear power plant

International Nuclear Information System (INIS)

Takechi, Eisuke; Matsutoshi, Makoto.

1978-01-01

Purpose: To arrange the units of waste processing devices in a number one more than the number thereof required for a plurality of reactors, and to make it usable commonly as a preliminary waste processing device thereby to effectively use all the gaseous waste processing devices. Constitution: A gaseous waste processing device is constituted by an exhaust gas extractor, a first processing device, a second processing device and the like, which are all connected in series. Upon this occasion, devices from the exhaust gas extractor to the first processing device and valves, which are provided in each of reactors, are arranged in series, on one hand, but valves at the downstream side join one another by one pipeline, and are connected to a stack through a total gaseous waste processing device, on another. (Yoshihara, H.)

Attachment of gaseous fission products to aerosols

International Nuclear Information System (INIS)

Skyrme, G.

1985-01-01

Accidents may occur in which the integrity of fuel cladding is breached and volatile fission products are released to the containment atmosphere. In order to assess the magnitude of the subsequent radiological hazard it is necessary to know the transport behaviour of such fission products. It is frequently assumed that the fission products remain in the gaseous phase. There is a possibility, however, that they may attach themselves to particles and hence substantially modify their transport properties. This paper provides a theoretical assessment of the conditions under which gaseous fission products may be attached to aerosol particles. Specific topics discussed are: the mass transfer of a gaseous fission product to an isolated aerosol particle in an infinite medium; the rate at which the concentration of fission products in the gas phase diminishes within a container as a result of deposition on a population of particles; and the distribution of deposited fission product between different particle sizes in a log-normal distribution. It is shown that, for a given mass, small particles are more efficient for fission product attachment, and that only small concentrations of such particles may be necessary to achieve rapid attachment. Conditions under which gaseous fission products are not attached to particles are also considered, viz, the competing processes of deposition onto the containment walls and onto aerosol particles, and the possibility of the removal of aerosols from the containment by various deposition processes, or agglomeration, before attachment takes place. (author)

U.S. forms uranium enrichment corporation

International Nuclear Information System (INIS)

Seltzer, R.

1993-01-01

After almost 40 years of operation, the federal government is withdrawing from the uranium enrichment business. On July 1, the Department of Energy turned over to a new government-owned entity--the US Enrichment Corp. (USEC)--both the DOE enrichment plants at Paducah, Ky., and Portsmouth, Ohio, and domestic and international marketing of enriched uranium from them. Pushed by the inability of DOE's enrichment operations to meet foreign competition, Congress established USEC under the National Energy Policy Act of 1992, envisioning the new corporation as the first step to full privatization. With gross revenues of $1.5 billion in fiscal 1992, USEC would rank 275th on the Fortune 500 list of top US companies. USEC will lease from DOE the Paducah and Portsmouth facilities, built in the early 1950s, which use the gaseous diffusion process for uranium enrichment. USEC's stock is held by the US Treasury, to which it will pay annual dividends. Martin Marietta Energy Systems, which has operated Paducah since 1984 and Portsmouth since 1986 for DOE, will continue to operate both plants for USEC. Closing one of the two facilities will be studied, especially in light of a 40% world surplus of capacity over demand. USEC also will consider other nuclear-fuel-related ventures. USEC will produce only low-enriched uranium, not weapons-grade material. Indeed, USEC will implement a contract now being completed under which the US will purchase weapons-grade uranium from dismantled Russian nuclear weapons and convert it into low-enriched uranium for power reactor fuel

Calculation of releases of radioactive materials in gaseous and liquid effluents from boiling water reactors (BWR-GALE Code)

International Nuclear Information System (INIS)

Bangart, R.L.; Bell, L.G.; Boegli, J.S.; Burke, W.C.; Lee, J.Y.; Minns, J.L.; Stoddart, P.G.; Weller, R.A.; Collins, J.T.

1978-12-01

The calculational procedures described in the report reflect current NRC staff practice. The methods described will be used in the evaluation of applications for construction permits and operating licenses docketed after January 1, 1979, until this NUREG is revised as a result of additional staff review. The BWR-GALE (Boiling Water Reactor Gaseous and Liquid Effluents) Code is a computerized mathematical model for calculating the release of radioactive material in gaseous and liquid effluents from boiling water reactors (BWRs). The calculations are based on data generated from operating reactors, field tests, laboratory tests, and plant-specific design considerations incorporated to reduce the quantity of radioactive materials that may be released to the environment

Daytime multispectral scanner aerial surveys of the Oak Ridge Reservation, 1992--1994: Overview of data processing and analysis by the Environmental Restoration Remote Sensing Program, Fiscal year 1995

International Nuclear Information System (INIS)

Smyre, J.L.; Hodgson, M.E.; Moll, B.W.; King, A.L.; Cheng, Yang.

1995-11-01

Environmental Restoration (ER) Remote Sensing and Special Surveys Program was in 1992 to apply the benefits of remote sensing technologies to Environmental Restoration Management (ERWM) programs at all of the five United States Department of Energy facilities operated and managed by Martin Marietta Energy Systems, Inc. (now Lockheed Martin Energy Systems)-the three Oak Ridge Reservation (ORR) facilities, the Paducah Gaseous Diffusion Plant (PGDP), the Portsmouth Gaseous Diffusion Plant (PORTS)-and adjacent off-site areas. The Remote Sensing Program includes the management of routine and special surveys at these sites, application of state-of-the-art remote sensing and geophysical technologies, and data transformation, integration, and analyses required to make the information valuable to ER. Remotely-sensed data collected of the ORR include natural color and color infrared (IR) aerial photography, 12-band multispectral scanner imagery, predawn thermal IR sensor imagery, magnetic and electromagnetic geophysical surveys, and gamma radiological data

Secondary incinerator for radioactive gaseous waste

International Nuclear Information System (INIS)

Takeda, Tadashi; Masuda, Takashi.

1997-01-01

A vessel incorporated with packings, in which at least either of the packings and the vessel is put to induction-heating by high frequency induction coils, is disposed in a flow channel of radioactive gaseous wastes exhausted from a radioactive waste incinerator. The packings include metals such as stainless pipes and electroconductive ceramics such as C-SiC ceramics. Since only electricity is used as an energy source, in the secondary incinerator for the radioactive gaseous wastes, it can be installed in a cell safely. In addition, if ceramics are used, there is no worry of deterioration of the incinerator due to organic materials, and essential functions are not lowered. (T.M.)

Astrophysics of gaseous nebulae and active galactic nuclei

International Nuclear Information System (INIS)

Osterbrock, D.E.

1989-01-01

A graduate-level text and reference book on gaseous nebulae and the emission regions in Seyfert galaxies, quasars, and other types of active galactic nuclei (AGN) is presented. The topics discussed include: photoionization equilibrium, thermal equilibrium, calculation of emitted spectrum, comparison of theory with observations, internal dynamics of gaseous nebulae, interstellar dust, regions in the galactic context, planetary nebulae, nova and supernova remnants, diagnostics and physics of AGN, observational results on AGN

Proposal for Construction/Demonstration/Implementation of A Material Handling System

International Nuclear Information System (INIS)

Jim Jnatt

2001-01-01

Vortec Corporation, the United States Enrichment Corporation (USEC) and DOE/Paducah propose to complete the technology demonstration and the implementation of the Material Handling System developed under Contract Number DE-AC21-92MC29120. The demonstration testing and operational implementation will be done at the Paducah Gaseous Diffusion Plant. The scope of work, schedule and cost for the activities are included in this proposal. A description of the facility to be constructed and tested is provided in Exhibit 1, attached. The USEC proposal for implementation at Paducah is presented in Exhibit 2, and the commitment letters from the site are included in Exhibit 3. Under our agreements with USEC, Bechtel Jacobs Corporation and DOE/Paducah, Vortec will be responsible for the construction of the demonstration facility as documented in the engineering design package submitted under Phase 4 of this contract on August 9, 2001. USEC will have responsibility for the demonstration testing and commercial implementation of the plant. The demonstration testing and initial commercial implementation of the technology will be achieved by means of a USEC work authorization task with the Bechtel Jacobs Corporation. The initial processing activities will include the processing of approximately 4,250 drums of LLW. Subsequent processing of LLW and TSCA/LLW will be done under a separate contract or work authorization task. To meet the schedule for commercial implementation, it is important that the execution of the Phase 4 project option for construction of the demonstration system be executed as soon as possible. The schedule we have presented herein assumes initiation of the construction phase by the end of September 2001. Vortec proposes to complete construction of the demonstration test system for an estimated cost of $3,254,422. This price is based on the design submitted to DOE/NETL under the Phase 4 engineering design deliverable (9 august 2001). The cost is subject to the

Innovative vitrification for soil remediation

Energy Technology Data Exchange (ETDEWEB)

Jetta, N.W.; Patten, J.S.; Hnat, J.G. [Vortec Corp., Collegeville, PA (United States)

1995-10-01

The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS{trademark}) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase I consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project.

Cost savings associated with landfilling wastes containing very low levels of uranium

International Nuclear Information System (INIS)

Boggs, C.J.; Shaddoan, W.T.

1996-01-01

The Paducah Gaseous Diffusion Plant (PGDP) has operated captive landfills (both residential and construction/demolition debris) in accordance with the Commonwealth of Kentucky regulations since the early 1980s. Typical waste streams allowed in these landfills include nonhazardous industrial and municipal solid waste (such as paper, plastic, cardboard, cafeteria waste, clothing, wood, asbestos, fly ash, metals, and construction debris). In July 1992, the U.S. Environmental Protection Agency issued new requirements for the disposal of sanitary wastes in a open-quotes contained landfill.close quotes These requirements were promulgated in the 401 Kentucky Administrative Record Chapters 47 and 48 that became effective 30 June 1995. The requirements for a new contained landfill include a synthetic liner made of high-density polyethylene in addition to the traditional 1-meter (3-foot) clay liner and a leachate collection system. A new landfill at Paducah would accept waste streams similar to those that have been accepted in the past. The permit for the previously existing landfills did not include radioactivity limits; instead, these levels were administratively controlled. Typically, if radioactivity was detected above background levels, the waste was classified as low-level waste (LLW), which would be sent off-site for disposal

Environmental Restoration Program pollution prevention performance measures for FY 1993 and 1994 remedial investigations

International Nuclear Information System (INIS)

1993-03-01

The Martin Marietta Energy Systems, Inc., Environmental Restoration (ER) Program adopted a Pollution Prevention Program in March 1991. The program's mission is to minimize waste and prevent pollution in remedial investigations (RI), feasibility studies (FS), decontamination and decommissioning (D ampersand D), and surveillance and maintenance (S ampersand M) site program activities. Mission success will result in volume and/or toxicity reduction of generated waste. Energy Systems is producing a fully developed a Numerical Scoring System (NSS) and actually scoring the generators of Investigation Derived Waste (IDW) at six ER sites: Oak Ridge National Laboratory (ORNL), the Oak Ridge Y-12 Plant, the Oak Ridge K-25 site, Paducah Gaseous Diffusion Plant (Paducah), and Portsmouth Uranium Enrichment Complex (Portsmouth). This report summarizes the findings of this initial numerical scoring evaluation and shows where improvements in the overall ER Pollution prevention program may be required. This report identifies a number of recommendations that, if implemented, would help to improve site-performance measures. The continued development of the NSS will support generators in maximizing their Pollution Prevention/Waste Minimization efforts. Further refinements of the NSS, as applicable suggest comments and/or recommendations for improvement

Nitrogen-system safety study: Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

1982-07-01

The Department of Energy has primary responsibility for the safety of operations at DOE-owned nuclear facilities. The guidelines for the analysis of credible accidents are outlined in DOE Order 5481.1. DOE has requested that existing plant facilities and operations be reviewed for potential safety problems not covered by standard industrial safety procedures. This review is being conducted by investigating individual facilities and documenting the results in Safety Study Reports which will be compiled to form the Existing Plant Final Safety Analysis Report which is scheduled for completion in September, 1984. This Safety Study documents the review of the Plant Nitrogen System facilities and operations and consists of Section 4.0, Facility and Process Description, and Section 5.0, Accident Analysis, of the Final Safety Analysis Report format. The existing nitrogen system consists of a Superior Air Products Company Type D Nitrogen Plant, nitrogen storage facilities, vaporization facilities and a distribution system. The system is designed to generate and distribute nitrogen gas used in the cascade for seal feed, buffer systems, and for servicing equipment when exceptionally low dew points are required. Gaseous nitrogen is also distributed to various process auxiliary buildings. The average usage is approximately 130,000 standard cubic feet per day

Environmental assessment for the construction, operation, and closure of the solid waste landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

1995-03-01

DOE has prepared an environmental assessment (EA) for the proposed construction, operation, and closure of a Solid Waste Landfill (SWL) that would be designed in accordance with Commonwealth of Kentucky landfill regulations (401 Kentucky Administrative Regulations Chapters 47 and 48 and Kentucky Revised Statutes 224.855). PGDP produces approximately 7,200 cubic yards per year of non-hazardous, non-radioactive solid waste currently being disposed of in a transitional contained (residential) landfill cell (Cell No. 3). New Kentucky landfill regulations mandate that all existing landfills be upgraded to meet the requirements of the new regulations or stop receiving wastes by June 30, 1995. Cell No. 3 must stop receiving wastes at that time and be closed and capped within 180 days after final receipt of wastes. The proposed SWL would occupy 25 acres of a 60-acre site immediately north of the existing PGDP landfill (Cell No. 3). The EA evaluated the potential environmental consequences of the proposed action and reasonable alternative actions. Based on the analysis in the EA, DOE has determined that the proposed action does not constitute a major Federal action which will significantly affect the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA), 42 USC 4321 et seq. Therefore, it is determined that an environmental impact statement will not be prepared, and DOE is issuing this FONSI

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices. [Appendices only

Energy Technology Data Exchange (ETDEWEB)

Liverman, James L.

1977-09-01

Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant. (LK)

Gaseous diffusion system

International Nuclear Information System (INIS)

Garrett, G.A.; Shacter, J.

1978-01-01

A gaseous diffusion system is described comprising a plurality of diffusers connected in cascade to form a series of stages, each of the diffusers having a porous partition dividing it into a high pressure chamber and a low pressure chamber, and means for combining a portion of the enriched gas from a succeeding stage with a portion of the enriched gas from the low pressure chamber of each stage and feeding it into one extremity of the high pressure chamber thereof

Monitoring and removal of gaseous carbon-14 species

International Nuclear Information System (INIS)

Kabat, M.J.

1979-01-01

A simple and efficient method was developed for the monitoring of low level carbon-14 in nuclear power station areas and gaseous effluent. Gaseous carbon compounds (hydrocarbons and CO) are catalytically oxidized to CO 2 , which is then absorbed on solid Ca(OH) 2 at elevated temperatures. The 14 C collected is quantitatively liberated by thermal decomposition of CaCO 3 as CO 2 , which is either measured directly by flow-through detectors or absorbed in alkali hydroxide followed by liquid scintillation counting. The method can also be used for the removal of gaseous 14 C. The Ca 14 CO 3 can be immobilized in concrete for long term disposal. Ca(OH) 2 is an inexpensive absorber. It is selective for CO 2 and has high capacity and efficiency for its absorption and retention. A theoretical evaluation of thee optium conditions for CO 2 absorption and liberation is discussed and experimental investigations are described. There is good agreement between theoretical predictions and experimental findings

Electronic document management system analysis report and system plan for the Environmental Restoration Program

International Nuclear Information System (INIS)

Frappaolo, C.

1995-09-01

Lockheed Martin Energy Systems, Inc. (LMES) has established and maintains Document Management Centers (DMCs) to support Environmental Restoration Program (ER) activities undertaken at three Oak Ridge facilities: Oak Ridge National Laboratory, Oak Ridge K-25 Site, Oak Ridge Y-12 Plant; and two sister sites: Portsmouth Gaseous Diffusion Plant in Portsmouth, Ohio, and Paducah Gaseous Diffusion Plant in Paducah, Kentucky. The role of the DMCs is to receive, store, retrieve, and properly dispose of records. In an effort to make the DMCs run more efficiently and to more proactively manage the records' life cycles from cradle to grave, ER has decided to investigate ways in which Electronic Document Management System (EDMS) technologies can be used to redefine the DMCs and their related processes. Specific goals of this study are tightening control over the ER documents, establishing and enforcing record creation and retention procedures, speeding up access to information, and increasing the accessibility of information. A working pilot of the solution is desired within the next six months. Based on a series of interviews conducted with personnel from each of the DMCs, key management, and individuals representing related projects, it is recommended that ER utilize document management, full-text retrieval, and workflow technologies to improve and automate records management for the ER program. A phased approach to solution implementation is suggested starting with the deployment of an automated storage and retrieval system at Portsmouth. This should be followed with a roll out of the system to the other DMCs, the deployment of a workflow-enabled authoring system at Portsmouth, and a subsequent roll out of this authoring system to the other sites

Dynamical instability of a charged gaseous cylinder

Science.gov (United States)

Sharif, M.; Mumtaz, Saadia

2017-10-01

In this paper, we discuss dynamical instability of a charged dissipative cylinder under radial oscillations. For this purpose, we follow the Eulerian and Lagrangian approaches to evaluate linearized perturbed equation of motion. We formulate perturbed pressure in terms of adiabatic index by applying the conservation of baryon numbers. A variational principle is established to determine characteristic frequencies of oscillation which define stability criteria for a gaseous cylinder. We compute the ranges of radii as well as adiabatic index for both charged and uncharged cases in Newtonian and post-Newtonian limits. We conclude that dynamical instability occurs in the presence of charge if the gaseous cylinder contracts to the radius R*.

Historical review of CEA researches on uranium enrichment

International Nuclear Information System (INIS)

Camarcat, N.

1997-01-01

The various uranium enrichment processes that have been studied at the CEA since 1953 are briefly reviewed: gaseous diffusion (which led to the construction of EURODIF plant), chemical treatments (which were abandoned in 1988 for cost reasons), gaseous ultracentrifugation, electromagnetic processes, laser techniques (since 1980) and especially the SILVA technique (atomic vapour laser isotopic separation) which could take the place of the gaseous diffusion technique when the EURODIF plant will need to be renewed before 2010

Control of semivolatile radionuclides in gaseous effluents at nuclear facilities

International Nuclear Information System (INIS)

1982-01-01

An up-to-date review is presented of the subject, combining the results of laboratory studies on control of the most important semivolatile radionuclides in gaseous effluents at nuclear facilities and the results of operating experience in that area. Ruthenium is the most significant semivolatile contaminant in gaseous effluents at nuclear facilities. Volatilization of ruthenium can be reduced by various means, in particular by adding reductants. Volatilized ruthenium can be retained by adsorbents such as silica gel and ferric-oxide-based materials. Decontamination factors in the order of 10 3 have been obtained with these adsorbents under optimum conditions. Volatilized ruthenium can also be removed by other equipment such as condensers and scrubbers. Experience with high-level liquid waste solidification plants has shown that, in general, ruthenium volatilization is in the order of 10% or more unless special treatment is undertaken. There is little experience with ruthenium adsorbers in plants. Silica gel seems to have performed best, with ruthenium decontamination factors of about 10 2 to 10 3 . However, feed-to-stack ruthenium decontamination factors of 10 9 or more have been obtained even without ruthenium adsorbers. Other semivolatiles are relatively insignificant under normal conditions because of a low level of volatilization potential or mass or activity in the inventory. Moreover, owing to particulate formation, they can be easily removed without specific equipment

Wire gaseous coordinate detectors and their applications in biomedical research

International Nuclear Information System (INIS)

Peshekhonov, V.D.

1986-01-01

Wire gaseous coordinate detectors continue to be a basic tool in experimental high-energy physics and are being intensively introduced into related areas of science and technology, particularly biomedical research. The constant evolution of these detectors allows broad application of their new modificatons: multistep chambers, low-pressure detectors, time-projection chambers, and so on, so that detector systems are enriched with new possibilities. In this review we give the operating principles and fundamental parameters of these detectors and discuss some examples of how they are used in experimental physics. We also explore some of the features of the use of these detectors for research in molecular biology and medical diagnostics for examples of existing and projected setups

Introduction to the nuclear criticality safety evaluation of facility X-705, Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Sheaffer, M.K.; Keeton, S.C.

1993-01-01

This report is the first in a series of documents that will evaluate nuclear criticality safety in the Decontamination and Recovery Facility, X-705, Portsmouth Gaseous Diffusion Plant. It provides an overview of the facility, categorizes its functions for future analysis, reviews existing NCS documentation, and explains the follow-on effort planned for X-705. A detailed breakdown of systems, subsystems, and operational areas is presented and cross-referenced to existing NCS documentation

Air pollution with gaseous emissions and methods for their removal

International Nuclear Information System (INIS)

Vassilev, Venceslav; Boycheva, Sylvia; Fidancevska, Emilija

2009-01-01

Information concerning gaseous pollutants generated in the atmosphere, as a result of fuel incineration processes in thermal power and industrial plants, was summarized. The main methods and technologies for flue gases purification from the most ecologically hazardous pollutants are comparatively discussed. Keywords: gaseous pollutants, aerosols, flue gas purification systems and technologies, air ecology control

UF{sub 6} cylinder inspections at PGDP

Energy Technology Data Exchange (ETDEWEB)

Lamb, G.W.; Whinnery, W.N. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Routine inspections of all UF{sub 6} cylinders at the Paducah Gaseous Diffusion Plant have been mandated by the Department of Energy. A specific UF{sub 6} cylinder inspection procedure for what items to inspect and training for the operators prior to inspection duty are described. The layout of the cylinder yards and the forms used in the inspections are shown. The large number of cylinders (>30,000) to inspect and the schedule for completion on the mandated time table are discussed. Results of the inspections and the actions to correct the deficiencies are explained. Future inspections and movement of cylinders for relocation of certain cylinder yards are defined.

Innovative technology summary report: Road Transportable Analytical Laboratory (RTAL)

International Nuclear Information System (INIS)

1998-10-01

The Road Transportable Analytical Laboratory (RTAL) has been used in support of US Department of Energy (DOE) site and waste characterization and remediation planning at Fernald Environmental Management Project (FEMP) and is being considered for implementation at other DOE sites, including the Paducah Gaseous Diffusion Plant. The RTAL laboratory system consists of a set of individual laboratory modules deployable independently or as an interconnected group to meet each DOE site's specific analysis needs. The prototype RTAL, deployed at FEMP Operable Unit 1 Waste Pits, has been designed to be synergistic with existing analytical laboratory capabilities, thereby reducing the occurrence of unplanned rush samples that are disruptive to efficient laboratory operations

Gaseous radioiodine transport in the air-forage-cow-milk system

International Nuclear Information System (INIS)

Black, S.C.; Douglas, R.L.; Barth, D.S.

1976-04-01

To study the transport of 131 I in the air-forage-cow milk system, a gaseous form of 131 I was released over a field of growing alfalfa which also contained some baled hay and dairy cows in pens. Some of the alfalfa was converted to hay and fed to cows, and some was used as green chop for other cows and goats. The results of this experiment suggest that the deposition velocity of gaseous iodine is much less than that for iodine bound to particulates; that cows ingesting hay secrete a higher percentage of 131 I in milk than cows ingesting green chop; that gaseous forms do not penetrate hay bales to any great extent; that the gaseous form is transferred to milk in a manner similar to particulate forms; that ingestion of contaminated forage results in 80 times as much 131 I transfer to milk as does inhalation exposure to the same cloud; and that goats transfer 131 I from forage to milk more efficiently than do dairy cows

The effect of gaseous ammonia on cobalt perrhenate

International Nuclear Information System (INIS)

Maslov, L.P.; Men'shikov, O.D.; Borisov, V.V.; Sorokin, S.I.; Krutovertsev, S.A.; Kharkevich, S.I.; Ivanova, O.M.

1994-01-01

The influence of humid air ammonia mixture on crystal pentahydrate of cobalt(2) perrhenate has been studied by the methods of PES, IR spectroscopy thermal analysis and electrophysical measurements. It is shown that with an increase in ammonia content in gaseous phase cobalt perrhenate successively transforms into diaquodiammine-, tetrammine- and μ-dioxo-bis-(tetrammine) derivatives of cobalt. Reversibility of dioxocomplex formation and a correlation between the change in electrophysical properties of crystal sample and change in ammonia content in gaseous phase are pointed out. 16 refs.; 4 figs.; 1 tab

Strategic plan for the utilization of remote sensing technologies in the environmental restoration program

International Nuclear Information System (INIS)

King, A.D.; Doll, W.E.; Durfee, R.C.; Luxmoore, R.J.; Conder, S.R.; Nyquist, J.E.

1993-12-01

The objectives of the Environmental Restoration (ER) Remote Sensing and Special Surveys Program are to apply state-of-the-art remote sensing and geophysical technologies and to manage routine and remotely-sensed examinations of the Oak Ridge Reservation (ORR), the Paducah Gaseous Diffusion Plant (PGDP), the Portsmouth Gaseous Diffusion Plant (PORTS), and their adjacent off-site areas. Repeated multispectral scanner (MSS) imagery, gamma, and photographic surveys will allow monitoring of the degradation that might occur in waste containment vessels and monitoring (at a later stage in the remediation life cycle) of improvements from restoration efforts and cleanup. These technologies, in combination with geophysical surveys, will provide an effective means for identifying unknown waste sites and contaminant transport pathways. All of the data will be maintained in a data base that will be accessible to site managers in the ER Program. The complete analysis of collected data will provide site-specific data to the ER Program for characterizing and monitoring ER Program hazardous waste sites

Strategic plan for the utilization of remote sensing technologies in the Environmental Restoration Program

International Nuclear Information System (INIS)

King, A.D.; Doll, W.E.; Durfee, R.C.; Luxmoore, R.J.; Conder, S.R.; Nyquist, J.E.

1994-03-01

The objectives of the Environmental Restoration (ER) Remote Sensing and Special Surveys Program are to apply state-of-the-art remote sensing and geophysical technologies and to manage routine and remotely-sensed examinations of the Oak Ridge Reservation (ORR), the Paducah Gaseous Diffusion Plant (PGDP), the Portsmouth Gaseous Diffusion Plant (PORTS), and their adjacent off-site areas. Repeated multispectral scanner (MSS) imagery, gamma, and photographic surveys will allow monitoring of the degradation that might occur in waste containment vessels and monitoring (at a later stage in the remediation life cycle) of improvements from restoration efforts and cleanup. These technologies, in combination with geophysical surveys, will provide an effective means for identifying unknown waste sites and contaminant transport pathways. All of the data will be maintained in a data base that will be accessible to site managers in the ER Program. The complete analysis of collected data will provide site-specific data to the ER Program for characterizing and monitoring ER Program hazardous waste sites

A Population Study of Gaseous Exoplanets

Science.gov (United States)

Tsiaras, A.; Waldmann, I. P.; Zingales, T.; Rocchetto, M.; Morello, G.; Damiano, M.; Karpouzas, K.; Tinetti, G.; McKemmish, L. K.; Tennyson, J.; Yurchenko, S. N.

2018-04-01

We present here the analysis of 30 gaseous extrasolar planets, with temperatures between 600 and 2400 K and radii between 0.35 and 1.9 R Jup. The quality of the HST/WFC3 spatially scanned data combined with our specialized analysis tools allow us to study the largest and most self-consistent sample of exoplanetary transmission spectra to date and examine the collective behavior of warm and hot gaseous planets rather than isolated case studies. We define a new metric, the Atmospheric Detectability Index (ADI) to evaluate the statistical significance of an atmospheric detection and find statistically significant atmospheres in around 16 planets out of the 30 analyzed. For most of the Jupiters in our sample, we find the detectability of their atmospheres to be dependent on the planetary radius but not on the planetary mass. This indicates that planetary gravity plays a secondary role in the state of gaseous planetary atmospheres. We detect the presence of water vapour in all of the statistically detectable atmospheres, and we cannot rule out its presence in the atmospheres of the others. In addition, TiO and/or VO signatures are detected with 4σ confidence in WASP-76 b, and they are most likely present in WASP-121 b. We find no correlation between expected signal-to-noise and atmospheric detectability for most targets. This has important implications for future large-scale surveys.

Purifying hydrocarbons in the gaseous stage

Energy Technology Data Exchange (ETDEWEB)

1937-02-01

Gaseous tar oils are subjected, at temperatures of 320 to 380/sup 0/C, to the action of a mixture of activated carbon mixed with powdered metal which removes the sulfur contamination from the substance to be purified.

Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production

Science.gov (United States)

Jujasz, Albert J.; Burkhart, James A.; Greenberg, Ralph

1988-01-01

A method for the separation of gaseous mixtures such as air and for producing medium purity oxygen, comprising compressing the gaseous mixture in a first compressor to about 3.9-4.1 atmospheres pressure, passing said compressed gaseous mixture in heat exchange relationship with sub-ambient temperature gaseous nitrogen, dividing the cooled, pressurized gaseous mixture into first and second streams, introducing the first stream into the high pressure chamber of a double rectification column, separating the gaseous mixture in the rectification column into a liquid oxygen-enriched stream and a gaseous nitrogen stream and supplying the gaseous nitrogen stream for cooling the compressed gaseous mixture, removing the liquid oxygen-enriched stream from the low pressure chamber of the rectification column and pumping the liquid, oxygen-enriched steam to a predetermined pressure, cooling the second stream, condensing the cooled second stream and evaporating the oxygen-enriched stream in an evaporator-condenser, delivering the condensed second stream to the high pressure chamber of the rectification column, and heating the oxygen-enriched stream and blending the oxygen-enriched stream with a compressed blend-air stream to the desired oxygen concentration.

Treatment of Plants with Gaseous Ethylene and Gaseous Inhibitors of Ethylene Action.

Science.gov (United States)

Tucker, Mark L; Kim, Joonyup; Wen, Chi-Kuang

2017-01-01

The gaseous nature of ethylene affects not only its role in plant biology but also how you treat plants with the hormone. In many ways, it simplifies the treatment problem. Other hormones have to be made up in solution and applied to some part of the plant hoping the hormone will be taken up into the plant and translocated throughout the plant at the desired concentration. Because all plant cells are connected by an intercellular gas space the ethylene concentration you treat with is relatively quickly reached throughout the plant. In some instances, like mature fruit, treatment with ethylene initiates autocatalytic synthesis of ethylene. However, in most experiments, the exogenous ethylene concentration is saturating, usually >1 μL L -1 , and the synthesis of additional ethylene is inconsequential. Also facilitating ethylene research compared with other hormones is that there are inhibitors of ethylene action 1-MCP (1-methylcyclopropene) and 2,5-NBD (2,5-norbornadiene) that are also gases wherein you can achieve nearly 100% inhibition of ethylene action quickly and with few side effects. Inhibitors for other plant hormones are applied as a solution and their transport and concentration at the desired site is not always known and difficult to measure. Here, our focus is on how to treat plants and plant parts with the ethylene gas and the gaseous inhibitors of ethylene action.

Nitrification inhibitors mitigated reactive gaseous nitrogen intensity in intensive vegetable soils from China.

Science.gov (United States)

Fan, Changhua; Li, Bo; Xiong, Zhengqin

2018-01-15

Nitrification inhibitors, a promising tool for reducing nitrous oxide (N 2 O) losses and promoting nitrogen use efficiency by slowing nitrification, have gained extensive attention worldwide. However, there have been few attempts to explore the broad responses of multiple reactive gaseous nitrogen emissions of N 2 O, nitric oxide (NO) and ammonia (NH 3 ) and vegetable yield to nitrification inhibitor applications across intensive vegetable soils in China. A greenhouse pot experiment with five consecutive vegetable crops was performed to assess the efficacies of two nitrification inhibitors, namely, nitrapyrin and dicyandiamide on reactive gaseous nitrogen emissions, vegetable yield and reactive gaseous nitrogen intensity in four typical vegetable soils representing the intensive vegetable cropping systems across mainland China: an Acrisol from Hunan Province, an Anthrosol from Shanxi Province, a Cambisol from Shandong Province and a Phaeozem from Heilongjiang Province. The results showed soil type had significant influences on reactive gaseous nitrogen intensity, with reactive gaseous nitrogen emissions and yield mainly driven by soil factors: pH, nitrate, C:N ratio, cation exchange capacity and microbial biomass carbon. The highest reactive gaseous nitrogen emissions and reactive gaseous nitrogen intensity were in Acrisol while the highest vegetable yield occurred in Phaeozem. Nitrification inhibitor applications decreased N 2 O and NO emissions by 1.8-61.0% and 0.8-79.5%, respectively, but promoted NH 3 volatilization by 3.2-44.6% across all soils. Furthermore, significant positive correlations were observed between inhibited N 2 O+NO and stimulated NH 3 emissions with nitrification inhibitor additions across all soils, indicating that reduced nitrification posed the threat of NH 3 losses. Additionally, reactive gaseous nitrogen intensity was significantly reduced in the Anthrosol and Cambisol due to the reduced reactive gaseous nitrogen emissions and increased

Transmission environmental scanning electron microscope with scintillation gaseous detection device

International Nuclear Information System (INIS)

Danilatos, Gerasimos; Kollia, Mary; Dracopoulos, Vassileios

2015-01-01

A transmission environmental scanning electron microscope with use of a scintillation gaseous detection device has been implemented. This corresponds to a transmission scanning electron microscope but with addition of a gaseous environment acting both as environmental and detection medium. A commercial type of low vacuum machine has been employed together with appropriate modifications to the detection configuration. This involves controlled screening of various emitted signals in conjunction with a scintillation gaseous detection device already provided with the machine for regular surface imaging. Dark field and bright field imaging has been obtained along with other detection conditions. With a progressive series of modifications and tests, the theory and practice of a novel type of microscopy is briefly shown now ushering further significant improvements and developments in electron microscopy as a whole. - Highlights: • Novel scanning transmission electron microscopy (STEM) with an environmental scanning electron microscope (ESEM) called TESEM. • Use of the gaseous detection device (GDD) in scintillation mode that allows high resolution bright and dark field imaging in the TESEM. • Novel approach towards a unification of both vacuum and environmental conditions in both bulk/surface and transmission mode of electron microscopy

Stress corrosion in gaseous environment

International Nuclear Information System (INIS)

Miannay, Dominique.

1980-06-01

The combined influences of a stress and a gaseous environment on materials can lead to brittleness and to unexpected delayed failure by stress corrosion cracking, fatigue cracking and creep. The most important parameters affering the material, the environment, the chemical reaction and the stress are emphasized and experimental works are described. Some trends for further research are given [fr

Migration from Gasoline to Gaseous Fuel for Small-scale Electricity Generation Systems

Directory of Open Access Journals (Sweden)

Sukandar Sukandar

2013-03-01

Full Text Available This paper describes a study that gives a consideration to change fuel source for electricity generator from gasoline to combustible gas. A gaseous fuel conversion technology is presented and its performance is compared with gasoline. In the experiment, two types of load were tested, resistive and resistive-inductive. By using both fuels mostly the power factor (Cos ? of resistive-inductive load variations were greater than 0.8, and they had slight difference on operational voltage. The drawback of using gaseous fuel is the frequency of the electricity might be up to 10 Hz deviated from the standard frequency (i.e. 50 Hz. In the lab scale experiment, the gasoline consumption increased proportionally with the load increase, while using gaseous fuel the consumption of gas equal for two different load value in the range of 50% maximum load, which is 100 gram per 15 minutes operation. Therefore, the use of gaseous generation system should have average power twice than the required load. The main advantage using gaseous fuel (liquefied petroleum gas or biogas compared to gasoline is a cleaner emitted gas after combustion.

The Gaseous Phase as a Probe of the Astrophysical Solid Phase Chemistry

Energy Technology Data Exchange (ETDEWEB)

Abou Mrad, Ninette; Duvernay, Fabrice; Isnard, Robin; Chiavassa, Thierry; Danger, Grégoire, E-mail: gregoire.danger@univ-amu.fr [Aix-Marseille Université, PIIM UMR-CNRS 7345, F-13397 Marseille (France)

2017-09-10

In support of space missions and spectroscopic observations, laboratory experiments on ice analogs enable a better understanding of organic matter formation and evolution in astrophysical environments. Herein, we report the monitoring of the gaseous phase of processed astrophysical ice analogs to determine if the gaseous phase can elucidate the chemical mechanisms and dominant reaction pathways occurring in the solid ice subjected to vacuum ultra-violet (VUV) irradiation at low temperature and subsequently warmed. Simple (CH{sub 3}OH), binary (H{sub 2}O:CH{sub 3}OH, CH{sub 3}OH:NH{sub 3}), and ternary ice analogs (H{sub 2}O:CH{sub 3}OH:NH{sub 3}) were VUV-processed and warmed. The evolution of volatile organic compounds in the gaseous phase shows a direct link between their relative abundances in the gaseous phase, and the radical and thermal chemistries modifying the initial ice composition. The correlation between the gaseous and solid phases may play a crucial role in deciphering the organic composition of astrophysical objects. As an example, possible solid compositions of the comet Lovejoy are suggested using the abundances of organics in its comae.

Study on the surface oxidation of uranium in different gaseous atmospheres

International Nuclear Information System (INIS)

Wang Xiaoling; Fu Yibei; Xie Renshou

1996-03-01

The studying for the surface oxidation of uranium and oxide by X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS), and the surface oxidation of uranium in different gaseous atmospheres such as O 2 , H 2 , CO, CO 2 , H 2 O(v) and air were reviewed. The surface oxidation of uranium is greatly influenced by a number of parameters including atmospheric temperature, pressure, diffusion of adsorbed gas atoms through the oxide layer, surface and interface chemical component, and defect structure and electron nature of the oxide layer. The initial oxidation mechanism and kinetics have been discussed. Suggestions for future work have also been presented. (32 refs., 7 figs., 5 tabs.)

Measurements of gaseous multiplication coefficient in pure isobutane

International Nuclear Information System (INIS)

Lima, Iara Batista de

2010-01-01

In this work it is presented measurements of gaseous multiplication coefficient (α) in pure isobutane obtained with a parallel plate chamber, protected against discharges by one electrode (anode) of high resistivity glass (ρ = 2 x 10 12 Ω.cm). The method applied was the Pulsed Townsend, where the primary ionization is produced through the incidence of a nitrogen laser beam onto a metallic electrode (cathode). The electric currents measured with the chamber operating in both ionization and avalanche regimes were used to calculate the gaseous multiplication coefficient by the solution of the Townsend equation for uniform electric fields. The validation of the technique was provided by the measurements of gaseous multiplication coefficient in pure nitrogen, a widely studied gas, which has well-established data in literature. The α coefficients in isobutane were measured as a function of the reduced electric field in the range of 139Td up to 208Td. The obtained values were compared with those simulated by Imonte software (version 4.5) and the only experimental results available in the literature, recently obtained in our group. This comparison showed that the results are concordant within the experimental errors. (author)

Dielectrophoretic separation of gaseous isotopes

International Nuclear Information System (INIS)

McConnell, D.B.

1975-01-01

Gaseous isotopes are separated from a mixture in a vertically elongated chamber by subjecting the mixture to a nonuniform transverse electric field. Dielectrophoretic separation of the isotopes is effected, producing a transverse temperature gradient in the chamber, thereby enhancing the separation by convective countercurrent flow. In the example given, the process and apparatus are applied to the production of heavy water from steam

Field pilot test of surfactant-enhanced remediation of trichloroethane DNAPL in a sand aquifer

International Nuclear Information System (INIS)

Jackson, R.E.; Butler, G.W.; Londergan, J.T.; Mariner, P.E.; Pickens, J.F.; Fountain, J.C.

1994-01-01

The sequence of lacustrine and outwash deposits beneath a vapor degreasing operation at the Paducah Gaseous Division Plant, Kentucky, is contaminated with trichloroethane due to leakage from a sewer/sump line. A plume of dissolved trichloroethane (TCE) extends throughout an area of approximately 3 km 2 in the Regional Gravel Aquifer (RGA) which is located between 20 and 30 meters below ground surface. It is suspected that some 40,000 liters of TCE might have escaped into the subsurface at Paducah, most of which is still present in the lacustrine deposits and the underlying RGA as DNAPL. A field test to confirm the presence of TCE DNAPL in the sandy, upper portion of the RGA around a monitoring well and to test the efficiency of the surfactant for TCE solubilization is described. The aqueous concentrations of TCE in this well have consistently been measured at 300--550 mg TCE/L over a period of three years. The use of Capillary and Bond numbers to estimate the improbability of mobilization of DNAPL due to the lowering of the interfacial tension is described. The multiphase, multicomponent simulator UTCHEM was used to simulate both the injection and extraction of the surfactant solution and the solubilization of the TCE by the surfactant micelles

Sevoflurane improves gaseous exchange and exerts protective ...

African Journals Online (AJOL)

Sevoflurane improves gaseous exchange and exerts protective effects in ... Lung water content and cell count were estimated by standard protocols. ... It reversed LPS-induced oxidative stress, as demonstrated by increase in total antioxidant ...

Transmission environmental scanning electron microscope with scintillation gaseous detection device.

Science.gov (United States)

Danilatos, Gerasimos; Kollia, Mary; Dracopoulos, Vassileios

2015-03-01

A transmission environmental scanning electron microscope with use of a scintillation gaseous detection device has been implemented. This corresponds to a transmission scanning electron microscope but with addition of a gaseous environment acting both as environmental and detection medium. A commercial type of low vacuum machine has been employed together with appropriate modifications to the detection configuration. This involves controlled screening of various emitted signals in conjunction with a scintillation gaseous detection device already provided with the machine for regular surface imaging. Dark field and bright field imaging has been obtained along with other detection conditions. With a progressive series of modifications and tests, the theory and practice of a novel type of microscopy is briefly shown now ushering further significant improvements and developments in electron microscopy as a whole. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid monitoring of gaseous fission products in BWRs using a portable spectrometer

International Nuclear Information System (INIS)

Yeh, Wei-Wen; Lee, Cheng-Jong; Chen, Chen-Yi; Chung, Chien

1996-01-01

Rapid, quantitative determination of gaseous radionuclides is the most difficult task in the field of environmental monitoring for radiation. Although the identification of each gaseous radionuclide is relatively straightforward using its decayed gamma ray as an index, the quantitative measurement is hampered by the time-consuming sample collection procedures, in particular for the radioactive noble gaseous fission products of krypton and xenon. In this work, a field gamma-ray spectrometer consisting of a high-purity germanium detector, portable multichannel anlayzer, and a notebook computer was used to conduct rapid scanning of radioactive krypton and xenon in the air around a nuclear facility

Biofuels and Bioproducts from Wet and Gaseous Waste Streams: Challenges and Opportunities

Energy Technology Data Exchange (ETDEWEB)

None, None

2017-01-09

This report draws together activities related to wet and gaseous waste feedstocks into a single document. It enables an amplified focus on feedstocks in the relevant technology and potential markets category. Also, this report helps to inform and support ongoing wet and gaseous resource recovery activities in the Bioenergy Technologies Office (BETO) and in the broader federal space. Historically, the office has identified wet and gaseous waste feedstocks as potentially advantageous, but has not pursued them with a sustained focus. This document seeks to position these waste streams appropriately alongside more traditional feedstocks in BETO efforts.

The development of gaseous detectors with solid photocathodes for low temperature applications

CERN Document Server

Periale, L.; Iacobaeus, C.; Francke, T.; Lund-Jensen, B.; Pavlopoulos, N.; Picchi, P.; Pietropaolo, F.

2004-01-01

There are several applications and fundamental research areas which require the detection of VUV light at cryogenic temperatures. For these applications we have developed and successfully tested special designs of gaseous detectors with solid photocathodes able to operate at low temperatures: sealed gaseous detectors with MgF2 windows and windowless detectors. We have experimentally demonstrated, that both primary and secondary (due to the avalanche multiplication inside liquids) scintillation lights could be recorded by photosensitive gaseous detectors. The results of this work may allow one to significantly improve the operation of some noble liquid gas TPCs.

Automated sampling and control of gaseous simulations

KAUST Repository

Huang, Ruoguan; Keyser, John

2013-01-01

In this work, we describe a method that automates the sampling and control of gaseous fluid simulations. Several recent approaches have provided techniques for artists to generate high-resolution simulations based on a low-resolution simulation

Electron beam gaseous pollutants treatment

International Nuclear Information System (INIS)

Chmielewski, A.G.

1999-01-01

Emission of gaseous pollutants, mostly during combustion of fossil fuels, creates a threat to the environment. New, economical technologies are needed for flue gas treatment. A physico-chemical basis of the process using electron beam for the simultaneous removal of sulfur and nitrogen oxides and volatile organic compounds are presented in this report. Development of the process and its upscaling has been discussed. (author)

NuMas: A LAN-based materials control and accounting system in production

International Nuclear Information System (INIS)

Strickland, T.W.; Bracey, J.T.; McMahon, S.A.

1995-01-01

A state-of-the-art Nuclear Materials Control and Accounting (NMC and A) System has been implemented and is fully operational at the Paducah Gaseous Diffusion Plant (PGDP) as of September 1994. The uranium enrichment facility is currently regulated by the Department of Energy (DOE) and is in the process of obtaining Nuclear Regulatory Commission (NRC) certification. Implementation of this system has resulted in a tremendous cost savings to the facility as well as improvements to the overall efficiency of the NMC and A department. This paper outlines the benefits of implementing a Personal Computer/Local Area Network (PC/LAN)-based system in hopes of attracting other facilities to explore and utilize its application at their sites

Depleted Uranium Hexafluoride Management Program. The technology assessment report for the long-term management of depleted uranium hexafluoride. Volume 1

Energy Technology Data Exchange (ETDEWEB)

Zoller, J.N.; Rosen, R.S.; Holliday, M.A. [and others

1995-06-30

With the publication of a Request for Recommendations and Advance Notice of Intent in the November 10, 1994 Federal Register, the Department of Energy initiated a program to assess alternative strategies for the long-term management or use of depleted uranium hexafluoride. This Request was made to help ensure that, by seeking as many recommendations as possible, Department management considers reasonable options in the long-range management strategy. The Depleted Uranium Hexafluoride Management Program consists of three major program elements: Engineering Analysis, Cost Analysis, and an Environmental Impact Statement. This Technology Assessment Report is the first part of the Engineering Analysis Project, and assesses recommendations from interested persons, industry, and Government agencies for potential uses for the depleted uranium hexafluoride stored at the gaseous diffusion plants in Paducah, Kentucky, and Portsmouth, Ohio, and at the Oak Ridge Reservation in Tennessee. Technologies that could facilitate the long-term management of this material are also assessed. The purpose of the Technology Assessment Report is to present the results of the evaluation of these recommendations. Department management will decide which recommendations will receive further study and evaluation. These Appendices contain the Federal Register Notice, comments on evaluation factors, independent technical reviewers resumes, independent technical reviewers manual, and technology information packages.

Depleted Uranium Hexafluoride Management Program. The technology assessment report for the long-term management of depleted uranium hexafluoride. Volume 1

International Nuclear Information System (INIS)

Zoller, J.N.; Rosen, R.S.; Holliday, M.A.

1995-01-01

With the publication of a Request for Recommendations and Advance Notice of Intent in the November 10, 1994 Federal Register, the Department of Energy initiated a program to assess alternative strategies for the long-term management or use of depleted uranium hexafluoride. This Request was made to help ensure that, by seeking as many recommendations as possible, Department management considers reasonable options in the long-range management strategy. The Depleted Uranium Hexafluoride Management Program consists of three major program elements: Engineering Analysis, Cost Analysis, and an Environmental Impact Statement. This Technology Assessment Report is the first part of the Engineering Analysis Project, and assesses recommendations from interested persons, industry, and Government agencies for potential uses for the depleted uranium hexafluoride stored at the gaseous diffusion plants in Paducah, Kentucky, and Portsmouth, Ohio, and at the Oak Ridge Reservation in Tennessee. Technologies that could facilitate the long-term management of this material are also assessed. The purpose of the Technology Assessment Report is to present the results of the evaluation of these recommendations. Department management will decide which recommendations will receive further study and evaluation. These Appendices contain the Federal Register Notice, comments on evaluation factors, independent technical reviewers resumes, independent technical reviewers manual, and technology information packages

Extruder system and method for treatment of a gaseous medium

Energy Technology Data Exchange (ETDEWEB)

Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

2016-04-05

A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

Techniques to limit gaseous releases in case of reactor accident. Choice criteria - present solutions

International Nuclear Information System (INIS)

Billard, Francois; Lavie, Jean-Marie

1964-10-01

Within the frame of the study of radiological risks associated with a reactor accident in order to define the required responses, this study comprises, on the one hand, an analysis of the different accident types in order to select typical accidents, and on the other hand, a site-based analysis to define the maximum admissible radioactivity release for a given site. The determination of minimum required coefficient of risk reduction results from a compromise between the choice of reactor configuration type and the efficiency of purification devices, while taking into account minimum characteristics of the enclosure mechanical strength, local release conditions, and nature of gaseous effluents to be processed. After a review of available containment techniques, the author applies this analysis method to the different French reactor types. He gives a brief description of adopted solutions for the most typical French reactors in terms of characteristics of venting and filtration devices. As data quality is a crucial requirement, the author outlines the need for further studies regarding fission product emission and transfer, the purification of gaseous effluents and their diffusion in the atmosphere [fr

Development of an integrated, in-situ remediation technology. Topical report for task No. 6: lab-scale development of microbial degradation process, September 26, 1994--May 25, 1996

International Nuclear Information System (INIS)

Odom, J.M.

1997-01-01

Contamination in low permeability soils poses a significant technical challenge to in situ remediation efforts. Poor accessibility to the contaminants and difficulty in delivery of treatment reagents have rendered existing in situ treatments such as bioremediation, vapor extraction, and pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites. The technology is an integrated in situ treatment in which established geotechnical methods are used to install degradation zones directly in the contaminated soil, and electro-osmosis is utilized to move the contaminants back and forth through those zones until the treatment is completed. The present Topical Report for Task No. 6 summarizes the results of a study of the potential for stimulating microbial reductive dehalogenation as part of the integrated in situ treatment process at the field experiment test site at DOE's Gaseous Diffusion Plant in Paducah, Kentucky. A series of open-quotes microcosm bottle testsclose quotes were performed on samples of contaminated soil and groundwater taken from the Paducah site and spiked with trichloroethene (TCE). A number of bottles were set up, each spiked with a different carbon source in order to enhance the growth of different microbial subpopulations already present within the indigenous population in the soil. In addition, a series of bottle tests were completed with samples of the granular activated carbon (GAC) treatment zone material retrieved from the test site during the Paducah field experiment. In these tests, the GAC samples were used in place of the soil. Results of the soil-groundwater microcosms yielded a negative indication of the presence of dechlorinating bacteria at the site. However, charcoal (GAC) samples from one location in the test plot exhibited marked dechlorination with conversion of TCE to dichloroethene

Removing Gaseous NH3 Using Biochar as an Adsorbent

Directory of Open Access Journals (Sweden)

Kyoung S. Ro

2015-09-01

Full Text Available Ammonia is a major fugitive gas emitted from livestock operations and fertilization production. This study tested the potential of various biochars in removing gaseous ammonia via adsorption processes. Gaseous ammonia adsorption capacities of various biochars made from wood shaving and chicken litter with different thermal conditions and activation techniques were determined using laboratory adsorption column tests. Ammonia adsorption capacities of non-activated biochars ranged from 0.15 to 5.09 mg·N/g, which were comparable to that of other commercial activated carbon and natural zeolite. There were no significant differences in ammonia adsorption capacities of steam activated and non-activated biochars even if the surface areas of the steam activated biochars were about two orders of magnitude greater than that of non-activated biochars. In contrast, phosphoric acid activation greatly increased the biochar ammonia adsorption capacity. This suggests that the surface area of biochar did not readily control gaseous NH3 adsorption. Ammonia adsorption capacities were more or less linearly increased with acidic oxygen surface groups of non-activated and steam-activated biochars. Phosphoric acid bound to the acid activated biochars is suspected to contribute to the exceptionally high ammonia adsorption capacity. The sorption capacities of virgin and water-washed biochar samples were not different, suggesting the potential to regenerate spent biochar simply with water instead of energy- and capital-intensive steam. The results of this study suggest that non-activated biochars can successfully replace commercial activated carbon in removing gaseous ammonia and the removal efficiency will greatly increase if the biochars are activated with phosphoric acid.

The Mass and Absorption Columns of Galactic Gaseous Halos

Science.gov (United States)

Qu, Zhijie; Bregman, Joel N.

2018-01-01

The gaseous halo surrounding the galaxy is a reservoir for the gas on the galaxy disk, supplying materials for the star formation. We developed a gaseous halo model connecting the galactic disk and the gaseous halo by assuming the star formation rate is equal to the radiative cooling rate. Besides the single-phase collisional gaseous halo, we also consider the photoionization effect and a time-independent cooling model that assumes the mass cooling rate is constant over all temperatures. The photoionization dominates the low mass galaxy and the outskirts of the massive galaxy due to the low-temperature or low-density nature. The multi-phase cooling model dominates the denser region within the cooling radius, where the efficient radiative cooling must be included. Applying these two improvements, our model can reproduce the most of observed high ionization state ions (i.e., O VI, O VII, Ne VIII and Mg X). Our models show that the O VI column density is almost a constant of around 10^14 cm^-2 over a wide stellar mass from M_\\star ~10^8 M_Sun to 10^11 M_Sun, which is constant with current observations. This model also implies the O VI is photoionized for the galaxy with a halo mass fraction function of the EAGLE simulation. Finally, our model predicts plateaus of the Ne VIII and the Mg X column densities above the sub-L^* galaxy, and the possibly detectable O VII and O VIII column densities for low-mass galaxies, which help to determine the required detection limit for the future observations and missions.

Global evaluation and calibration of a passive air sampler for gaseous mercury

Science.gov (United States)

McLagan, David S.; Mitchell, Carl P. J.; Steffen, Alexandra; Hung, Hayley; Shin, Cecilia; Stupple, Geoff W.; Olson, Mark L.; Luke, Winston T.; Kelley, Paul; Howard, Dean; Edwards, Grant C.; Nelson, Peter F.; Xiao, Hang; Sheu, Guey-Rong; Dreyer, Annekatrin; Huang, Haiyong; Hussain, Batual Abdul; Lei, Ying D.; Tavshunsky, Ilana; Wania, Frank

2018-04-01

Passive air samplers (PASs) for gaseous mercury (Hg) were deployed for time periods between 1 month and 1 year at 20 sites across the globe with continuous atmospheric Hg monitoring using active Tekran instruments. The purpose was to evaluate the accuracy of the PAS vis-à-vis the industry standard active instruments and to determine a sampling rate (SR; the volume of air stripped of gaseous Hg per unit of time) that is applicable across a wide range of conditions. The sites spanned a wide range of latitudes, altitudes, meteorological conditions, and gaseous Hg concentrations. Precision, based on 378 replicated deployments performed by numerous personnel at multiple sites, is 3.6 ± 3.0 %1, confirming the PAS's excellent reproducibility and ease of use. Using a SR previously determined at a single site, gaseous Hg concentrations derived from the globally distributed PASs deviate from Tekran-based concentrations by 14.2 ± 10 %. A recalibration using the entire new data set yields a slightly higher SR of 0.1354 ± 0.016 m3 day-1. When concentrations are derived from the PAS using this revised SR the difference between concentrations from active and passive sampling is reduced to 8.8 ± 7.5 %. At the mean gaseous Hg concentration across the study sites of 1.54 ng m-3, this represents an ability to resolve concentrations to within 0.13 ng m-3. Adjusting the sampling rate to deployment specific temperatures and wind speeds does not decrease the difference in active-passive concentration further (8.7 ± 5.7 %), but reduces its variability by leading to better agreement in Hg concentrations measured at sites with very high and very low temperatures and very high wind speeds. This value (8.7 ± 5.7 %) represents a conservative assessment of the overall uncertainty of the PAS due to inherent uncertainties of the Tekran instruments. Going forward, the recalibrated SR adjusted for temperature and wind speed should be used, especially if conditions are highly variable or

Charge Transfer Properties Through Graphene for Applications in Gaseous Detectors

CERN Document Server

Franchino, S.; Hall-Wilton, R.; Jackman, R.B.; Muller, H.; Nguyen, T.T.; de Oliveira, R.; Oliveri, E.; Pfeiffer, D.; Resnati, F.; Ropelewski, L.; Smith, J.; van Stenis, M.; Streli, C.; Thuiner, P.; Veenhof, R.

2016-07-11

Graphene is a single layer of carbon atoms arranged in a honeycomb lattice with remarkable mechanical and electrical properties. Regarded as the thinnest and narrowest conductive mesh, it has drastically different transmission behaviours when bombarded with electrons and ions in vacuum. This property, if confirmed in gas, may be a definitive solution for the ion back-flow problem in gaseous detectors. In order to ascertain this aspect, graphene layers of dimensions of about 2x2cm$^2$, grown on a copper substrate, are transferred onto a flat metal surface with holes, so that the graphene layer is freely suspended. The graphene and the support are installed into a gaseous detector equipped with a triple Gaseous Electron Multiplier (GEM), and the transparency properties to electrons and ions are studied in gas as a function of the electric fields. The techniques to produce the graphene samples are described, and we report on preliminary tests of graphene-coated GEMs.

Detector for gaseous nuclear fission products

International Nuclear Information System (INIS)

Kobayashi, Yoshihiro; Kubo, Katsumi.

1979-01-01

Purpose: To facilitate the fabrication of a precipitator type detector, as well as improve the reliability. Constitution: Gas to be measured flown in an anode is stored in a gas processing system. By applying a voltage between the anode and the cathode, if positively charged Rb or Cs which is the daughter products of gaseous fission products are present in the gas to be measured, the daughter products are successively deposited electrostatically to the cathode. The daughter products issue beta-rays and gamma-rays to ionize the argon gas at the anode, whereby ionizing current flows between both of the electrodes. Pulses are generated from the ionizing current, and presence or absence, as well as the amount of the gaseous fission products are determined by the value recorded for the number of the pulses to thereby detect failures in the nuclear fuel elements. After the completion of the detection, the inside of the anode is evacuated and the cathode is heated to evaporate and discharge the daughter products externally. This eliminates the effects of the former detection to the succeeding detection. (Moriyama, K.)

Novel gaseous detectors for medical imaging

International Nuclear Information System (INIS)

Danielsson, M.; Fonte, P.; Francke, T.; Iacobaeus, C.; Ostling, J.; Peskov, V.

2004-01-01

We have developed and successfully tested prototypes of two new types of gaseous detectors for medical imaging purposes. The first one is called the Electronic Portal Imaging Device (EPID). It is oriented on monitoring and the precise alignment of the therapeutic cancer treatment beam (pulsed gamma radiation) with respect to the patient's tumor position. The latest will be determined from an X-ray image of the patient obtained in the time intervals between the gamma pulses. The detector is based on a 'sandwich' of hole-type gaseous detectors (GEM and glass microcapillary plates) with metallic gamma and X-ray converters coated with CsI layers. The second detector is an X-ray image scanner oriented on mammography and other radiographic applications. It is based on specially developed by us high rate RPCs that are able to operate at rates of 10 5 Hz/mm 2 with a position resolution better than 50 μm at 1 atm. The quality of the images obtained with the latest version of this device were in most cases more superior than those obtained from commercially available detectors

Production of 41Ar and 79Kr gaseous radiotracers for industrial applications

International Nuclear Information System (INIS)

Yelgaonkar, V.N.; Jagadeesan, K.C.; Shivarudrappa, V.; Sharma, V.K.; Chitra, S.

2007-01-01

Radiotracers are extensively used in many industries for trouble shooting and optimization of process parameters leading to considerable savings in time and huge economic benefits. In chemical and petrochemical industries different gases and vapours flowing in the conversion reactors play a major role in the final production. Gaseous radiotracers are ideal to study hydrodynamics of gas phases in process vessels. 41 Ar and 79 Kr are the preferred gaseous radiotracers for such studies. Owing to the increase in demand from Indian industries for gas phase radiotracers, efforts have been made to produce 41 Ar and 79 Kr indigenously by irradiation of 40 Ar and enriched 78 Kr gaseous targets in research reactors. Prequalification of the containers used, safety aspects concerning accidental rupture and mandatory tests necessary for irradiation of gaseous targets in the reactors have been studied. The paper describes some of the important safety aspects involved and the results of trial irradiations on the production of 41 Ar and 79 Kr radiotracers. Standardization of suitable assay protocols for their regular production and supply for applications in industries is also described. (author)

On-line measurement of gaseous iodine species during a PWR severe accident

Energy Technology Data Exchange (ETDEWEB)

Haykal, I.; Doizi, D. [CEA, DEN, Departement de Physico-chimie, 91191 Gif sur Yvette Cedex, (France); Perrin, A. [CNRS-University of Paris Est and Paris 7, Laboratoire Inter-Universitaire des Systemes Atmospheriques, 94010 Creteil, (France); Vincent, B. [University of Burgundy, Laboratoire de physique, CNRS UMR 5027, 9, Avenue Alain Savary, BP 47870, F-21078 Dijon Cedex, (France); Manceron, L. [Synchrotron SOLEIL, L' Orme des Merisiers, St-Aubin BP48, 91192 Gif-sur-Yvette Cedex, (France); Mejean, G. [University of Joseph Fourier in Grenoble, Laboratoire de Spectrometrie Physique-CNRS UMR 5588, 38402 Saint Martin d' Heres, (France); Ducros, G. [CEA Cadarache, CEA, DEN, Departement d' Etudes des Combustibles, 13108 Saint-Paul-lez-Durance cedex, (France)

2015-07-01

A long-range remote sensing of severe accidents in nuclear power plants can be obtained by monitoring the online emission of volatile fission products such as xenon, krypton, caesium and iodine. The nuclear accident in Fukushima was ranked at level 7 of the International Nuclear Event Scale by the NISA (Nuclear and Industrial Safety Agency) according to the importance of the radionuclide release and the off-site impact. Among volatile fission products, iodine species are of high concern, since they can be released under aerosols as well as gaseous forms. Four years after the Fukushima accident, the aerosol/gaseous partition is still not clear. Since the iodine gaseous forms are less efficiently trapped by the Filtered Containment Venting Systems than aerosol forms, it is of crucial importance to monitor them on-line during a nuclear accident, in order to improve the source term assessment in such a situation. Therefore, we propose to detect and quantify these iodine gaseous forms by the use of highly sensitive optical methods. (authors)

Radiolytical oxidation of gaseous iodine by beta radiation

International Nuclear Information System (INIS)

Kaerkelae, Teemu; Auvinen, Ari; Kekki, Tommi; Kotiluoto, Petri; Lyyraenen, Jussi; Jokiniemi, Jorma

2015-01-01

Iodine is one of the most radiotoxic fission product released from fuel during a severe nuclear power plant accident. Within the containment building, iodine compounds can react e.g. on the painted surfaces and form gaseous organic iodides. In this study, it was found out that gaseous methyl iodide (CH 3 I) is oxidised when exposed to beta radiation in an oxygen containing atmosphere. As a result, nucleation of aerosol particles takes place and the formation of iodine oxide particles is suggested. These particles are highly hygroscopic. They take up water from the air humidity and iodine oxides dissolve within the droplets. In order to mitigate the possible source term, it is of interest to understand the effect of beta radiation on the speciation of iodine.

Radiolytical oxidation of gaseous iodine by beta radiation

Energy Technology Data Exchange (ETDEWEB)

Kaerkelae, Teemu; Auvinen, Ari; Kekki, Tommi; Kotiluoto, Petri; Lyyraenen, Jussi [VTT Technical Research Centre of Finland, Espoo (Finland); Jokiniemi, Jorma [VTT Technical Research Centre of Finland, Espoo (Finland); Eastern Finland Univ., Kuopio (Finland)

2015-07-01

Iodine is one of the most radiotoxic fission product released from fuel during a severe nuclear power plant accident. Within the containment building, iodine compounds can react e.g. on the painted surfaces and form gaseous organic iodides. In this study, it was found out that gaseous methyl iodide (CH{sub 3}I) is oxidised when exposed to beta radiation in an oxygen containing atmosphere. As a result, nucleation of aerosol particles takes place and the formation of iodine oxide particles is suggested. These particles are highly hygroscopic. They take up water from the air humidity and iodine oxides dissolve within the droplets. In order to mitigate the possible source term, it is of interest to understand the effect of beta radiation on the speciation of iodine.

Analytical approaches for arsenic determination in air: A critical review

Energy Technology Data Exchange (ETDEWEB)

Sánchez-Rodas, Daniel, E-mail: rodas@uhu.es [Centre for Research in Sustainable Chemistry-CIQSO, Associated Unit CSIC-University of Huelva “Atmospheric Pollution”, Campus El Carmen, University of Huelva, 21071 Huelva (Spain); Department of Chemistry and Materials Science, University of Huelva, 21071 Huelva (Spain); Sánchez de la Campa, Ana M. [Centre for Research in Sustainable Chemistry-CIQSO, Associated Unit CSIC-University of Huelva “Atmospheric Pollution”, Campus El Carmen, University of Huelva, 21071 Huelva (Spain); Department of Mining, Mechanic and Energetic Engineering, ETSI, University of Huelva, 21071 Huelva (Spain); Alsioufi, Louay [Centre for Research in Sustainable Chemistry-CIQSO, Associated Unit CSIC-University of Huelva “Atmospheric Pollution”, Campus El Carmen, University of Huelva, 21071 Huelva (Spain)

2015-10-22

This review describes the different steps involved in the determination of arsenic in air, considering the particulate matter (PM) and the gaseous phase. The review focuses on sampling, sample preparation and instrumental analytical techniques for both total arsenic determination and speciation analysis. The origin, concentration and legislation concerning arsenic in ambient air are also considered. The review intends to describe the procedures for sample collection of total suspended particles (TSP) or particles with a certain diameter expressed in microns (e.g. PM10 and PM2.5), or the collection of the gaseous phase containing gaseous arsenic species. Sample digestion of the collecting media for PM is described, indicating proposed and established procedures that use acids or mixtures of acids aided with different heating procedures. The detection techniques are summarized and compared (ICP-MS, ICP-OES and ET-AAS), as well those techniques capable of direct analysis of the solid sample (PIXE, INAA and XRF). The studies about speciation in PM are also discussed, considering the initial works that employed a cold trap in combination with atomic spectroscopy detectors, or the more recent studies based on chromatography (GC or HPLC) combined with atomic or mass detectors (AFS, ICP-MS and MS). Further trends and challenges about determination of As in air are also addressed. - Highlights: • Review about arsenic in the air. • Sampling, sample treatment and analysis of arsenic in particulate matter and gaseous phase. • Total arsenic determination and arsenic speciation analysis.

Detection of gaseous fission products in water - a method of monitoring fuel sheathing failures

Energy Technology Data Exchange (ETDEWEB)

Tunnicliffe, P. R.; Whittier, A. C.

1959-05-15

The gaseous activities stripped from samples of effluent coolant from the NRU fuel elements tested in the central thimble of the NRX reactor (NRU loop) and from the NRX main effluent have been investigated. The activities obtained from the NRU loop can be attributed to gaseous fission products only. Design data have been obtained for a 'Gaseous Fission Product Monitor' to be installed for use with the NRU reactor. It is expected that this monitor will have high sensitivity to activity indicative of an incipient fuel element sheath failure. No qualitative determination of the various gaseous activities obtained from the NRX effluent has been made. A strong component of 25 {+-}1 seconds half-life is not consistent with O-19. Limited information concerning sheath failures in NRX was obtained. Of six failures observed in parallel with the installed delayed neutron monitors, three of these gave pre-warnings and in each case the gaseous fission product monitor showed a substantially greater sensitivity. An experiment in which small samples of uranium, inserted into the NRX reactor, could be exposed at will to a stream of water showed the behaviour of the two types of monitors to be similar. However, a number of signals were detected only by the gaseous fission product monitor. These can be attributed to its sensitivity to relatively long lived fission products. (author)

Effects of radiation and impurities on gaseous iodine behavior in a containment vessel

International Nuclear Information System (INIS)

Takahashi, Masato; Watanabe, Atsushi; Hashimoto, Takashi

2000-01-01

In order to estimate the effect of impurities and radiation on gaseous iodine behavior in containment vessel, NUPEC has improved IMPAIR-3 code developed by PSI. Several modifications on the iodine oxidation by radiolysis and the production of nitric acid, the existence of boric acid, and the reaction of silver particle with iodine were newly added in evaluating the effect of radiolysis and impurities. pH change resulting from presence of boric acid, nitric acid production by radiolysis of air, and sodium hydroxide addition by AM operation, was also considered. The code verification for pH change was performed using the RTF experimental results. Additionally, the effects of boric acid and silver impurities on gaseous iodine behavior were evaluated by the sensitivity analysis. As a result, the experimental results of iodine concentration transient under pH change were well simulated. The following results were also obtained from the sensitive analysis. The gaseous iodine behavior was not affected by the existence of boric acid. In the case of silver existence in liquid phase, the gaseous iodine concentration rapidly decreased because a large amount of iodine changed into AgI species in liquid phase. The restraint effect of silver on gaseous iodine, production was larger than that of pH change. (author)

Radiation protection with consumer products containing gaseous tritium light sources; Strahlenschutz bei Konsumguetern mit Tritium-Gaslichtquellen

Energy Technology Data Exchange (ETDEWEB)

Rahders, Erio; Haeusler, Uwe [Bundesamt fuer Strahlenschutz, Berlin (Germany)

2017-08-01

Consumer products containing gaseous tritium light sources (GTLS) were examined with respect to their radiological safety potential regarding leak tightness or accidents. The maximum tritium leakage rate of 2.7 Bq/d determined from experimental testing is well below the criterion for leak tightness of sealed radioactive sources in DIN 25426-4. In order to investigate the incorporation of tritium due to contact with consumer products, 2 scenarios were reviewed; the correct use of a tritium watch and the accident scenario with a keyring.

Rare earths in iron and steelmaking and gaseous desulphurisation

International Nuclear Information System (INIS)

Kay, D.A.R.; Subramanian, S.V.; Meng, V.; Kumar, R.V.

1985-01-01

Rare earth (RE) additions, either as mischmetal or rare earth silicide, are used in many ladle treatment processes in modern ferrous metallurgy. In ironmaking they provide the basis for the control of graphite morphology in cast irons and in steelmaking additions are made to aluminum-killed steels for desulphurisation and the control of inclusion composition and morphology. Rare earth oxides may also be used in the desulphurisation of medium calorific value gaseous fuels and stack gases. In this paper, Ce-S-O and La-S-O phase stability diagrams are used to determine the role of the rare earths in the external processing of iron and steel, and gaseous desulphurisation

Gas phase decontamination of gaseous diffusion process equipment

International Nuclear Information System (INIS)

Bundy, R.D.; Munday, E.B.; Simmons, D.W.; Neiswander, D.W.

1994-01-01

D ampersand D of the process facilities at the gaseous diffusion plants (GDPs) will be an enormous task. The EBASCO estimate places the cost of D ampersand D of the GDP at the K-25 Site at approximately $7.5 billion. Of this sum, nearly $4 billion is associated with the construction and operation of decontamination facilities and the dismantlement and transport of contaminated process equipment to these facilities. In situ long-term low-temperature (LTLT) gas phase decontamination is being developed and demonstrated at the K-25 site as a technology that has the potential to substantially lower these costs while reducing criticality and safeguards concerns and worker exposure to hazardous and radioactive materials. The objective of gas phase decontamination is to employ a gaseous reagent to fluorinate nonvolatile uranium deposits to form volatile LJF6, which can be recovered by chemical trapping or freezing. The LTLT process permits the decontamination of the inside of gas-tight GDP process equipment at room temperature by substituting a long exposure to subatmospheric C1F for higher reaction rates at higher temperatures. This paper outlines the concept for applying LTLT gas phase decontamination, reports encouraging laboratory experiments, and presents the status of the design of a prototype mobile system. Plans for demonstrating the LTLT process on full-size gaseous diffusion equipment are also outlined briefly

Two new sources of reactive gaseous mercury in the free troposphere

OpenAIRE

H. Timonen; J. L. Ambrose; D. A. Jaffe

2012-01-01

Mercury (Hg) is a neurotoxin that bioaccumulates in the food chain. Mercury is emitted to the atmosphere primarily in its elemental form, which has a long lifetime allowing global transport. It is known that atmospheric oxidation of gaseous elemental mercury (GEM) generates reactive gaseous mercury (RGM) which plays an important role in the atmospheric mercury cycle by enhancing the rate of mercury deposition to ecosystems. However, the primary GEM oxidants, and the sources and chemical ...

Liquid and Gaseous Waste Operations Department Annual Operating Report, CY 1993

International Nuclear Information System (INIS)

Maddox, J.J.; Scott, C.B.

1994-02-01

This report summarizes the activities of the waste management operations section of the liquid and gaseous waste operations department at ORNL for 1993. The process waste, liquid low-level waste, gaseous waste systems activities are reported, as well as the low-level waste solidification project. Upgrade activities is the various waste processing and treatment systems are summarized. A maintenance activity overview is provided, and program management, training, and other miscellaneous activities are covered

Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant, January--December 1995

Energy Technology Data Exchange (ETDEWEB)

Kszos, L.A. [ed.

1996-04-01

The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (benthic macroinvertebrates, fish). This report focuses on ESD activities occurring from Jan. 1995 to Dec. 1995, although activities conducted outside this period are included as appropriate.

Using Artificial Neural Networks to Forecast Trichloroethylene Concentrations at the Paducah Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Kopp, Joshua D [Univ of KY, Dept of Civil Engineering

2007-05-01

To determine the future extent of the TCE contamination plume at PGDP, a groundwater and solute transport model has been developed by the Department of Energy (DOE). The model used to perform these calculations is MODFLOWT which is an enhanced groundwater transport model developed by the United States Geological Survey (USGS). MODFLOWT models groundwater movement as well as the transport of species that are subject to adsorption and decay by using a finite difference method (Duffield et al 2001). A significant limitation of MODFLOWT is that it requires large amounts of data. This data can be difficult and expensive to obtain. MODFLOWT also requires excessive computational time to perform one simulation. It is desirable to have a model that can predict the spatial extent of the contaminant plume without as much required data and that does not require excessive computational times. The purpose of this study is to develop and alternative model to MODFLOWT that can produce similar results for possible use in a companion management model. The alternative model used in this study is an artificial neural network (ANN).

Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant, January--December 1995

International Nuclear Information System (INIS)

Kszos, L.A.

1996-04-01

The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (benthic macroinvertebrates, fish). This report focuses on ESD activities occurring from Jan. 1995 to Dec. 1995, although activities conducted outside this period are included as appropriate

Global evaluation and calibration of a passive air sampler for gaseous mercury

Directory of Open Access Journals (Sweden)

D. S. McLagan

2018-04-01

Full Text Available Passive air samplers (PASs for gaseous mercury (Hg were deployed for time periods between 1 month and 1 year at 20 sites across the globe with continuous atmospheric Hg monitoring using active Tekran instruments. The purpose was to evaluate the accuracy of the PAS vis-à-vis the industry standard active instruments and to determine a sampling rate (SR; the volume of air stripped of gaseous Hg per unit of time that is applicable across a wide range of conditions. The sites spanned a wide range of latitudes, altitudes, meteorological conditions, and gaseous Hg concentrations. Precision, based on 378 replicated deployments performed by numerous personnel at multiple sites, is 3.6 ± 3.0 %1, confirming the PAS's excellent reproducibility and ease of use. Using a SR previously determined at a single site, gaseous Hg concentrations derived from the globally distributed PASs deviate from Tekran-based concentrations by 14.2 ± 10 %. A recalibration using the entire new data set yields a slightly higher SR of 0.1354 ± 0.016 m3 day−1. When concentrations are derived from the PAS using this revised SR the difference between concentrations from active and passive sampling is reduced to 8.8 ± 7.5 %. At the mean gaseous Hg concentration across the study sites of 1.54 ng m−3, this represents an ability to resolve concentrations to within 0.13 ng m−3. Adjusting the sampling rate to deployment specific temperatures and wind speeds does not decrease the difference in active–passive concentration further (8.7 ± 5.7 %, but reduces its variability by leading to better agreement in Hg concentrations measured at sites with very high and very low temperatures and very high wind speeds. This value (8.7 ± 5.7 % represents a conservative assessment of the overall uncertainty of the PAS due to inherent uncertainties of the Tekran instruments. Going forward, the recalibrated SR adjusted for temperature and wind speed

Hardware implementation of the ORNL fissile mass flow monitor

International Nuclear Information System (INIS)

McEvers, J.; Sumner, J.; Jones, R.; Ferrell, R.; Martin, C.; Uckan, T.; March-Leuba, J.

1998-01-01

This paper provides an overall description of the implementation of the Oak Ridge National Laboratory (ORNL) Fissile Mass Flow Monitor, which is part of a Blend Down Monitoring System (BDMS) developed by the US Department of Energy (DOE). The Fissile Mass Flow Monitor is designed to measure the mass flow of fissile material through a gaseous or liquid process stream. It consists of a source-modulator assembly, a detector assembly, and a cabinet that houses all control, data acquisition, and supporting electronics equipment. The development of this flow monitor was first funded by DOE/NE in September 95, and an initial demonstration by ORNL was described in previous INMM meetings. This methodology was chosen by DOE/NE for implementation in November 1996, and the hardware/software development is complete. Successful BDMS installation and operation of the complete BDMS has been demonstrated in the Paducah Gaseous Diffusion Plant (PGDP), which is operated by Lockheed Martin Utility Services, Inc. for the US Enrichment Corporation and regulated by the Nuclear Regulatory Commission. Equipment for two BDMS units has been shipped to the Russian Federation

The Martin Marietta Energy Systems personnel neutron dosimetry program

International Nuclear Information System (INIS)

McMahan, K.L.

1991-01-01

Martin Marietta Energy Systems, Inc. (Energy Systems), manages five sites for the US Department of Energy. Personnel dosimetry for four of the five sites is coordinated through a Centralized External Dosimetry System (CEDS). These four sites are the Oak Ridge National Laboratory (ORNL), the Oak Ridge Y-12 Plant (Y-12), the Oak Ridge K-25 Site (K-25), and the Paducah Gaseous Diffusion Plant (PGDP). The fifth Energy Systems site, Portsmouth Gaseous Diffusion Plant, has an independent personnel dosimetry program. The current CEDS personnel neutron dosimeter was first issued in January 1989, after an evaluation and characterization of the dosimeters' response in the workplaces was performed. For the workplace characterization, Energy Systems contracted with Pacific Northwest Laboratory (PNL) to perform neutron measurements at selected locations at ORNL and Y-12. K-25 and PGDP were not included because their neutron radiation fields were similar to others already planned for characterization at ORNL and Y-12. Since the initial characterization, PNL has returned to Oak Ridge twice to perform follow up measurements, and another visit is planned in the near future

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF6) in the diffusion cascade

International Nuclear Information System (INIS)

Huffer, J.E.

1997-04-01

This paper determines the nuclear safety of gaseous UF 6 in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF 6 in plant operations

Respiratory system. Part 2: Gaseous exchange.

Science.gov (United States)

McLafferty, Ella; Johnstone, Carolyn; Hendry, Charles; Farley, Alistair

This article, which isthe last in the life sciences series and the second of two articles on the respiratory system, describes gaseous exchange in the lungs, transport of oxygen and carbon dioxide, and internal and external respiration. The article concludes with a brief consideration of two conditions that affect gas exchange and transport: carbon monoxide poisoning and chronic obstructive pulmonary disease.

Photosensitive Gaseous Detectors for Cryogenic Temperature Applications

CERN Document Server

Periale, L; Iacobaeus, C; Lund-Jensen, B; Picchi, P; Pietropaolo, F

2007-01-01

There are several proposals and projects today for building LXe Time Projection Chambers (TPCs) for dark matter search. An important element of these TPCs are the photomultipliers operating either inside LXe or in vapors above the liquid. We have recently demonstrated that photosensitive gaseous detectors (wire type and hole-type) can operate perfectly well until temperatures of LN2. In this paper results of systematic studies of operation of the photosensitive version of these detectors (combined with reflective or semi-transparent CsI photocathodes) in the temperature interval of 300-150 K are presented. In particular, it was demonstrated that both sealed and flushed by a gas detectors could operate at a quite stable fashion in a year/time scale. Obtained results, in particular the long-term stability of photosensitive gaseous detectors, strongly indicate that they can be cheap and simple alternatives to photomultipliers or avalanche solid-state detectors in LXe TPC applications.

Trends and new developments in gaseous detectors

CERN Document Server

AUTHOR|(CDS)2069485

2004-01-01

Almost one century ago the method of particle detection with gaseous detectors was invented. Since then they have been exploited successfully in many experiments using a wide variety of different applications. The development is still going on today. The underlying working principles are today well understood and with the help of modern simulation techniques, new configurations can be easily examined and optimized before a first experimental test. Traditional wire chamber ensembles demonstrate that they are still up to date and are well prepared to meet also the challenges of LHC. Applications will be discussed using TPCs in high multiplicity environments with standard Multi-Wire Proportional Chamber (MWPC) as readout as well as drift tubes in a muon spectrometer for a Large Hadron Collider (LHC) experiment. Triggered by the evolving printed circuit technology, a new generation of gaseous detectors with very high position resolution and rate capability has emerged. Two representatives (MICROMEGAS, GEM) have p...

Hydrogenating gaseous hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Nicolardot, P L.F.

1930-08-06

Gaseous hydrocarbons obtained by the destructive distillation of carbonaceous materials are simultaneously desulfurized and hydrogenated by passing them at 350 to 500/sup 0/C, mixed with carbon monoxide and water vapor over lime mixed with metallic oxides present in sufficient amount to absorb the carbon dioxide as it is formed. Oxides of iron, copper, silver, cobalt, and metals of the rare earths may be used and are mixed with the lime to form a filling material of small pieces filling the reaction vessel which may have walls metallized with copper and zinc dust. The products are condensed and fixed with absorbents, e.g. oils, activated carbon, silica gels. The metallic masses may be regenerated by a hot air stream and by heating in inert gases.

Retention of gaseous isotopes

International Nuclear Information System (INIS)

Yarbro, O.O.; Mailen, J.C.; Stephenson, M.J.

1977-01-01

Retention of gaseous fission products during fuel reprocessing has, in the past, been limited to a modest retention of 131 I when processing fuels decayed less than about 180 days. The projected rapid growth of the nuclear power industry along with a desire to minimize environmental effects is leading to the reassessment of requirements for retention of gaseous fission products, including 131 I, 129 I, 85 Kr, 3 H, and 14 C. Starting in the late 1960s, a significant part of the LMFBR reprocessing development program has been devoted to understanding the behavior of gaseous fission products in plant process and effluent streams and the development of advanced systems for their removal. Systems for iodine control include methods for evolving up to 99% of the iodine from dissolver solutions to minimize its introduction and distribution throughout downstream equipment. An aqueous scrubbing system (Iodox) using 20 M HNO 3 as the scrubbing media effectively removes all significant iodine forms from off-gas streams while handling the kilogram quantities of iodine present in head-end and dissolver off-gas streams. Silver zeolite is very effective for removing iodine forms at low concentration from the larger-volume plant off-gas streams. Removal of iodine from plant liquid effluents by solid sorbents either prior to or following final vaporization appears feasible. Krypton is effectively released during dissolution and can be removed from the relatively small volume head-end and dissolver off-gas stream. Two methods appear applicable for removal and concentration of krypton: (1) selective absorption in fluorocarbons, and (2) cryogenic absorption in liquid nitrogen. The fluorocarbon absorption process appears to be rather tolerant of the normal contaminants (H 2 O, CO 2 , NOsub(x), and organics) present in typical reprocessing plant off-gas whereas the cryogenic system requires an extensive feed gas pretreatment system. Retention of tritium in a reprocessing plant is

Balance and behavior of gaseous radionuclides released during initial PWR fuel reprocessing operations

International Nuclear Information System (INIS)

Leudet, A.; Miquel, P.; Goumondy, P.J.; Charrier, G.

1982-08-01

Five fuel pins, taken from a PWR fuel assembly with 32000 MWD/t burn-up were chopped and dissolved in leak-proof equipment designed for accurate determination of the composition and quantity of gaseous elements released in these operations. Analytical methods were specially developped to determine directly the noble gases, tritium and gaseous carbon compounds in the gas phase. Volatile iodine was kept as close as possible to the source by cold traps, then transferred to a caustic solution for quantitative analysis. The quantities and activities of gaseous fission products thus determined were compared with predicted values obtained through computation. Very good agreement was generally observed

Balance and behavior of gaseous radionuclides released during initial PWR fuel reprocessing operations

International Nuclear Information System (INIS)

Leudet, A.; Miquel, P.; Goumondy, P.J.; Charrier, G.

1983-01-01

Five fuel pins, taken from a PWR fuel assembly with 32,000 MwD/t burn-up were chopped and dissolved in leak-proof equipment designed for accurate determination of the composition and quantity of gaseous elements released in these operations. Analytical methods were specially developed to determine directly the noble gases, tritium and gaseous carbon compounds in the gas phase. Volatile iodine was kept as close as possible to the source by cold traps, then transferred to a caustic solution for quantitative analysis. The quantities and activities of gaseous fission products thus determined were compared with predicted values obtained through computation. Very good agreement was generally observed

Turbulence enhancement by ultrasonically induced gaseous cavitation in the CO2 saturated water

International Nuclear Information System (INIS)

Lee, Seung Youp; Choi, Young Don

2002-01-01

Recent primary concern for the design of high performance heat exchanger and highly integrated electronic equipment is to develop an active and creative technologies which enhance the heat transfer without obstructing the coolant flows. In this study, we found through the LDV measurement that the gaseous cavitation induced by ultrasonic vibration applied to the CO 2 saturated water in the square cross-sectioned straight duct flow enhances the turbulence much more than the case of non-ultrasonic or normal ultrasonic conditions without gaseous cavitation does. We also found that gaseous cavitation can enhance effectively the turbulent heat transfer between the heating surfaces and coolants by destructing the viscous sublayer

A gaseous scintillation counter filled with He3 for neutron spectrometry

International Nuclear Information System (INIS)

Baldin, S.A.; Matveev, V.V.

1962-01-01

The paper describes a gas plant and gaseous scintillation counter, and gives the results of experiments on the recording and spectrometry of neutron beams using a gaseous scintillation counter filled with a mixture of 10% xenene and 90% helium-3 at an overall pressure of 20 ata. Data are given on the design of the gas plant, which makes it possible to operate the counter continuously over long periods of time, as well as providing the required gas mixtures at overall pressures of up to 60 atm and ensuring constant freedom of the gas from contamination. In addition, the paper presents the results of research on the counter's energy resolution and linearity at different energy levels and indicates its efficiency in gamma fields of intensity up to 3 r/h; the possibility of extending the working energy-range of gaseous scintillation counters filled with helium-3 is also considered. (author) [fr

Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

Energy Technology Data Exchange (ETDEWEB)

Selim, M.Y.E. [United Arab Emirates University, Al-Ain (United Arab Emirates). Dept. of Mechanical Engineering

2004-02-01

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters. (author)

Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition

International Nuclear Information System (INIS)

Selim, Mohamed Y.E.

2004-01-01

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line analysis. The effects of engine speeds, loads, pilot injection angle, pilot fuel quantity and compression ratio on combustion noise, knocking torque, thermal efficiency and maximum pressure are examined for the dual engine running on the three gaseous fuels separately. The combustion noise, knocking and ignition limits are found to relate to the type of gaseous fuels and to the engine design and operating parameters

Distribution of xenon between gaseous and liquid CO2

International Nuclear Information System (INIS)

Ackley, R.D.; Notz, K.J.

1976-10-01

The distribution of xenon at low concentrations between gaseous and liquid CO 2 was measured over essentially the entire liquid range of CO 2 . These measurements involved using a collimated radiation-detection cell to determine the relative quantities of 133 Xe-traced xenon in the separate phases contained in a vertical cylinder under isothermal conditions. The results are expressed in terms of a distribution ratio (mole fraction of xenon in the gaseous phase divided by mole fraction of xenon in the liquid phase) which decreased from 7.53 at -54.8 0 C to 1.10 at 30.5 0 C. These data were used to calculate various other solubility-related quantities

Method of producing gaseous products using a downflow reactor

Science.gov (United States)

Cortright, Randy D; Rozmiarek, Robert T; Hornemann, Charles C

2014-09-16

Reactor systems and methods are provided for the catalytic conversion of liquid feedstocks to synthesis gases and other noncondensable gaseous products. The reactor systems include a heat exchange reactor configured to allow the liquid feedstock and gas product to flow concurrently in a downflow direction. The reactor systems and methods are particularly useful for producing hydrogen and light hydrocarbons from biomass-derived oxygenated hydrocarbons using aqueous phase reforming. The generated gases may find used as a fuel source for energy generation via PEM fuel cells, solid-oxide fuel cells, internal combustion engines, or gas turbine gensets, or used in other chemical processes to produce additional products. The gaseous products may also be collected for later use or distribution.

Assessment of methods for analyzing gaseous mixtures of hydrogen isotopes and helium

International Nuclear Information System (INIS)

Attalla, A.; Bishop, C.T.; Bohl, D.R.; Buxton, T.L.; Sprague, R.E.; Warner, D.K.

1976-01-01

Mass spectrographic methods have served well in the past to analyze gaseous mixtures of the hydrogen isotopes. Alternate methods of analyses are reviewed which offer wider ranges and variety of isotopic determinations. This report describes possible improvements of the mass spectrographic determinations, gas chromatography, anti-Stokes Raman spectroscopy, microwave-induced optical emission spectroscopy, and methods of measuring tritium using radiation detection devices. Precision, accuracy, limitations, and costs are included for some of the methods mentioned. Costs range from $70,000 for the anti-Stokes Raman spectroscopy equipment, which can determine hydrogen isotopes but not helium, to less than $10,000 for the gas chromatographic equipment, which can determine hydrogen isotopes and helium with precision and accuracy comparable to those of the mass spectrometer

Container for gaseous samples for irradiation at accelerators

International Nuclear Information System (INIS)

Kupsch, H.; Riemenschneider, J.; Leonhardt, J.

1985-01-01

The invention concerns a container for gaseous samples for the irradiation at accelerators especially to generate short-lived radioisotopes. The container is also suitable for storage and transport of the target gas and can be multiply reused

Safety aspects of the design of a PWR gaseous radwaste treatment system using hydrogen recombiners

International Nuclear Information System (INIS)

Glibert, R.; Nuyt, G.; Herin, S.; Fossion, P.

1978-01-01

PWR Gaseous radwaste treatment system is essential for the reduction of impact on environment of the nuclear power plants. Decay tank system has been used for the retention of the radioactive gaseous fission products generated in the primary coolant. The use of a system combining decay tanks and hydrogen recombiner units is described in this paper. Accent is put on the safety aspects of this gaseous radwaste treatment facilitystudied by BN for a Belgian Power Plant. (author)

Technological aspects of gaseous pixel detectors fabrication

NARCIS (Netherlands)

Blanco Carballo, V.M.; Salm, Cora; Smits, Sander M.; Schmitz, Jurriaan; Melai, J.; Chefdeville, M.A.; van der Graaf, H.

2007-01-01

Integrated gaseous pixel detectors consisting of a metal punctured foil suspended in the order of 50μm over a pixel readout chip by means by SU-8 insulating pillars have been fabricated. SU-8 is used as sacrificial layer but metallization over uncrosslinked SU-8 presents adhesion and stress

Method for estimate the economic characteristics of an uranium enrichment plant by gaseous diffusion

International Nuclear Information System (INIS)

Berault, J.C.

1975-01-01

To estimate the economic characteristics of an uranium enrichment plant by gaseous diffusion is to determine the prospective price of the separative work unit to which leads the concerned technology, and to collect the data allowing to ascertain that this price remains in the area of development of the prices forecasted by the other projects. The prospective price estimated by the promoter is the synthesis of the components of the go decision and which are a potential market and a comprehensive industrially proven plant design, including the basic economic and technical data of the project. Procedures for estimating these components and their synthesis, exclusive of financing problems are reviewed [fr

Oak Ridge National Lebroatory Liquid&Gaseous Waste Treatment System Strategic Plan

Energy Technology Data Exchange (ETDEWEB)

Van Hoesen, S.D.

2003-09-09

Excellence in Laboratory operations is one of the three key goals of the Oak Ridge National Laboratory (ORNL) Agenda. That goal will be met through comprehensive upgrades of facilities and operational approaches over the next few years. Many of ORNL's physical facilities, including the liquid and gaseous waste collection and treatment systems, are quite old, and are reaching the end of their safe operating life. The condition of research facilities and supporting infrastructure, including the waste handling facilities, is a key environmental, safety and health (ES&H) concern. The existing infrastructure will add considerably to the overhead costs of research due to increased maintenance and operating costs as these facilities continue to age. The Liquid Gaseous Waste Treatment System (LGWTS) Reengineering Project is a UT-Battelle, LLC (UT-B) Operations Improvement Program (OIP) project that was undertaken to develop a plan for upgrading the ORNL liquid and gaseous waste systems to support ORNL's research mission.

Testing of one-inch UF{sub 6} cylinder valves under simulated fire conditions

Energy Technology Data Exchange (ETDEWEB)

Elliott, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Accurate computational models which predict the behavior of UF{sub 6} cylinders exposed to fires are required to validate existing firefighting and emergency response procedures. Since the cylinder valve is a factor in the containment provided by the UF{sub 6} cylinder, its behavior under fire conditions has been a necessary assumption in the development of such models. Consequently, test data is needed to substantiate these assumptions. Several studies cited in this document provide data related to the behavior of a 1-inch UF{sub 6} cylinder valve in fire situations. To acquire additional data, a series of tests were conducted at the Paducah Gaseous Diffusion Plant (PGDP) under a unique set of test conditions. This document describes this testing and the resulting data.

Calibration measurements using the ORNL fissile mass flow monitor

International Nuclear Information System (INIS)

March-Leuba, J.; Uckan, T.; Sumner, J.; Mattingly, J.; Mihalczo, J.

1998-01-01

This paper presents a demonstration of fissile-mass-flow measurements using the Oak Ridge National Laboratory (ORNL) Fissile Mass Flow Monitor in the Paducah Gaseous Diffusion Plant (PGDP). This Flow Monitor is part of a Blend Down Monitoring System (BDMS) that will be installed in at least two Russian Federation (R.F.) blending facilities. The key objectives of the demonstration of the ORNL Flow Monitor are two: (a) demonstrate that the ORNL Flow Monitor equipment is capable of reliably monitoring the mass flow rate of 235 UF 6 gas, and (b) provide a demonstration of ORNL Flow Monitor system in operation with UF 6 flow for a visiting R.F. delegation. These two objectives have been met by the PGDP demonstration, as presented in this paper

Technical documentation of HGSYSTEM/UF6 model

International Nuclear Information System (INIS)

Hanna, S.R.; Chang, J.C.; Zhang, J.X.

1996-01-01

MMES has been directed to upgrade the safety analyses for the gaseous diffusion plants at Paducah KY and Piketon OH. These will require assessment of consequences of accidental releases of UF 6 to the atmosphere at these plants. The HGSYSTEM model has been chosen as the basis for evaluating UF 6 releases; it includes dispersion algorithms for dense gases and treats the chemistry and thermodynamics of HF, a major product of the reaction of UF 6 with water vapor in air. Objective of this project was to incorporate additional capability into HGSYSTEM: UF 6 chemistry and thermodynamics, plume lift-off algorithms, and wet and dry deposition. The HGSYSTEM modules are discussed. The hybrid HGSYSTEM/UF 6 model has been evaluated in three ways

Evaluation of natural attenuation processes for trichloroethylene and technetium-99 in the Northeast and Northwest plumes at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

International Nuclear Information System (INIS)

Clausen, J.L.; Sturchio, N.C.; Heraty, L.J.; Huang, L.; Abrajano, T.

1997-01-01

NA processes such as biodegradation, sorption, dilution dispersion, advection, and possibly sorption and diffusion are occurring in the Northeast and Northwest plumes. However, the overall biological attenuation rate for TCE within the plumes is not sufficiently rapid to utilize as remedial option. The mobility and toxicity of 99 Tc is not being reduced by attenuating processes within the Northwest Plume. The current EPA position is that NA is not a viable remedial approach unless destructive processes are present or processes are active which reduce the toxicity and mobility of a contaminant. Therefore, active remediation of the dissolved phase plumes will be necessary to reduce contaminant concentrations before an NA approach could be justified at PGDP for either plume. Possible treatment methods for the reduction of dissolved phase concentrations within the plumes are pump-and-treat bioaugmentation, biostimulation, or multiple reactive barriers. Another possibility is the use of a regulatory instrument such as an Alternate Concentration Limit (ACL) petition. Biodegradation of TCE is occurring in both plumes and several hypothesis are possible to explain the apparent conflicts with some of the geochemical data. The first hypothesis is active intrinsic bioremediation is negligible or so slow to be nonmeasurable. In this scenario, the D.O., chloride, TCE, and isotopic results are indicative of past microbiological reactions. It is surmised in this scenario, that when the initial TCE release occurred, sufficient energy sources were available for microorganisms to drive aerobic reduction of TCE, but these energy sources were rapidly depleted. The initial degraded TCE has since migrated to downgradient locations. In the second scenario, TCE anaerobic degradation occurs in organic-rich micro-environments within a generally aerobic aquifer. TCE maybe strongly absorbed to organic-rich materials in the aquifer matrix and degraded by local Immunities of microbes, perhaps even under anaerobic conditions. Chloride, generated by degradation in such microenvironment is released rapidly into the water, as is CO 2 , from respiration of the microorganisms. TCE and its organic degradation products are retained on the aquifer matrix by sorption, and released more slowly into the groundwater. In this process, chloride produced from the microbial reaction may become separated in the plume from the residual TCE. This may explain why the chloride isotope ratio and dissolved TCE do not correlate with the DIC isotope ratio. The relationship between the δ 37 Cl values of TCE and dissolved inorganic chloride is consistent with what would be expected from the degradation of TCE, but is complicated by the elevated levels of background chloride, presumably due to agriculture practice, and complex behavior of TCE in the aquifer

Evaluation of natural attenuation processes for trichloroethylene and technetium-99 in the Northeast and Northwest plumes at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

Energy Technology Data Exchange (ETDEWEB)

Clausen, J.L.; Sturchio, N.C.; Heraty, L.J.; Huang, L.; Abrajano,T.

1997-11-25

NA processes such as biodegradation, sorption, dilution dispersion, advection, and possibly sorption and diffusion are occurring in the Northeast and Northwest plumes. However, the overall biological attenuation rate for TCE within the plumes is not sufficiently rapid to utilize as remedial option. The mobility and toxicity of {sup 99}Tc is not being reduced by attenuating processes within the Northwest Plume. The current EPA position is that NA is not a viable remedial approach unless destructive processes are present or processes are active which reduce the toxicity and mobility of a contaminant. Therefore, active remediation of the dissolved phase plumes will be necessary to reduce contaminant concentrations before an NA approach could be justified at PGDP for either plume. Possible treatment methods for the reduction of dissolved phase concentrations within the plumes are pump-and-treat bioaugmentation, biostimulation, or multiple reactive barriers. Another possibility is the use of a regulatory instrument such as an Alternate Concentration Limit (ACL) petition. Biodegradation of TCE is occurring in both plumes and several hypothesis are possible to explain the apparent conflicts with some of the geochemical data. The first hypothesis is active intrinsic bioremediation is negligible or so slow to be nonmeasurable. In this scenario, the D.O., chloride, TCE, and isotopic results are indicative of past microbiological reactions. It is surmised in this scenario, that when the initial TCE release occurred, sufficient energy sources were available for microorganisms to drive aerobic reduction of TCE, but these energy sources were rapidly depleted. The initial degraded TCE has since migrated to downgradient locations. In the second scenario, TCE anaerobic degradation occurs in organic-rich micro-environments within a generally aerobic aquifer. TCE maybe strongly absorbed to organic-rich materials in the aquifer matrix and degraded by local Immunities of microbes, perhaps even under anaerobic conditions. Chloride, generated by degradation in such microenvironment is released rapidly into the water, as is CO{sub 2}, from respiration of the microorganisms. TCE and its organic degradation products are retained on the aquifer matrix by sorption, and released more slowly into the groundwater. In this process, chloride produced from the microbial reaction may become separated in the plume from the residual TCE. This may explain why the chloride isotope ratio and dissolved TCE do not correlate with the DIC isotope ratio. The relationship between the {delta}{sup 37}Cl values of TCE and dissolved inorganic chloride is consistent with what would be expected from the degradation of TCE, but is complicated by the elevated levels of background chloride, presumably due to agriculture practice, and complex behavior of TCE in the aquifer.

Contribution to the study of gaseous molecular iodine washout by natural rains

International Nuclear Information System (INIS)

Fournier-Bidoz, V.

1991-01-01

This study is part of researches about nuclear accident prediction consequences on the environment. It concerns transfering of molecular gaseous iodine into liquids and especially precipitation scavenging below the cloud (washout). Bibliographic data directly concerned with this study (iodine's aqueous chemistry, aqueous to gaseous phases transfer) and also with its global frame-work (atmospheric release from a nuclear reactor in accidental situation and the behaviour of atmospheric iodine) are presented. Several experimental approaches have been performed in laboratory and on field. An aqueous to gaseous phase transfer simulator allowed us to isolate parameters involved in absorption and desorption of the halogen. Field experiments permit to quantify dry deposition on different solutions and to get a better insight of the phenomenon. Extrapolation of the whole results to precipitation scavenging of gaseous iodine I 2 by natural rains suggests that the process is an irreversible one. Washout rate values acquired during rainy experiments with molecular iodine emission or in a laboratory rainfall simulator agree with literatures data relative to irreversibility. However and even if reversibility was efficient it was not possible to clearly exhibit it according to experimental conditions. Moreover, the analytical iodine method which leads to a good experimental study has been presented

2 π gaseous flux proportional detector

International Nuclear Information System (INIS)

Guevara, E.A.; Costello, E.D.; Di Carlo, R.O.

1986-01-01

A counting system has been developed in order to measure carbon-14 samples obtained in the course of a study of a plasmapheresis treatment for diabetic children. The system is based on the use of a 2π gaseous flux proportional detector especially designed for the stated purpose. The detector is described and experiment results are given, determining the characteristic parameters which set up the working conditions. (Author) [es

Salient features in the preparation of gaseous tritium filled luminous light sources

International Nuclear Information System (INIS)

Mathew, K.M.; Ravi, S.; Subramanian, T.K.; Ananthakrishnan, M.

2003-01-01

Beta radiation emanating from gaseous tritium in close proximity with copper activated zinc sulphide phosphor provides self sustained light sources and these sources are used for nocturnal illumination of liquid crystal display in digital watches and clocks, product advertisements, exit signs etc. We report herein the preparation of low specific radioactivity gaseous tritium (29.5 Ci/m mole; 1.09 TBq/m mole) filled light sources and its effect on light output. (author)

Analytical and numerical study of a gaseous plasma dipole in the UHF frequency band

NARCIS (Netherlands)

Melazzi, Davide; Lancellotti, Vito; Capobianco, Antonio Daniele

2017-01-01

Gaseous plasma antennas are appealing in applications in which reconfigurability is desired, because the radiation properties can be changed by tuning the plasma parameters. In this paper, an analytical and numerical analysis of a gaseous plasma dipole that works in the 0.3-3 GHz frequency range is

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF{sub 6}) in the diffusion cascade

Energy Technology Data Exchange (ETDEWEB)

Huffer, J.E. [Parallax, Inc., Atlanta, GA (United States)

1997-04-01

This paper determines the nuclear safety of gaseous UF{sub 6} in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF{sub 6} in plant operations..

Monitoring gaseous CO2 and ethanol above champagne glasses: flute versus coupe, and the role of temperature.

Directory of Open Access Journals (Sweden)

Gérard Liger-Belair

Full Text Available In champagne tasting, gaseous CO(2 and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO(2 and ethanol was monitored through micro-gas chromatography (μGC, all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO(2 was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO(2 visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO(2 found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO(2 escaping the liquid phase into the form of bubbles.

Monitoring gaseous CO2 and ethanol above champagne glasses: flute versus coupe, and the role of temperature.

Science.gov (United States)

Liger-Belair, Gérard; Bourget, Marielle; Pron, Hervé; Polidori, Guillaume; Cilindre, Clara

2012-01-01

In champagne tasting, gaseous CO(2) and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO(2) and ethanol was monitored through micro-gas chromatography (μGC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO(2) was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO(2) visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO(2) found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO(2) escaping the liquid phase into the form of bubbles.

Solid–gaseous phase transformation of elemental contaminants during the gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Jiang, Ying; Ameh, Abiba [Centre for Bioenergy & Resource Management, School of Energy, Environment & Agrifood, Cranfield University, Cranfield MK43 0AL (United Kingdom); Lei, Mei [Centre for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China); Duan, Lunbo [Key Laboratory of Energy Thermal Conversion and Control, Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096 (China); Longhurst, Philip, E-mail: P.J.Longhurst@cranfield.ac.uk [Centre for Bioenergy & Resource Management, School of Energy, Environment & Agrifood, Cranfield University, Cranfield MK43 0AL (United Kingdom)

2016-09-01

Disposal of plant biomass removed from heavy metal contaminated land via gasification achieves significant volume reduction and can recover energy. However, these biomass often contain high concentrations of heavy metals leading to hot-corrosion of gasification facilities and toxic gaseous emissions. Therefore, it is of significant interest to gain a further understanding of the solid–gas phase transition of metal(loid)s during gasification. Detailed elemental analyses (C, H, O, N and key metal/metalloid elements) were performed on five plant species collected from a contaminated site. Using multi-phase equilibria modelling software (MTDATA), the analytical data allows modelling of the solid/gas transformation of metal(loid)s during gasification. Thermodynamic modelling based on chemical equilibrium calculations was carried out in this study to predict the fate of metal(loid) elements during typical gasification conditions and to show how these are influenced by metal(loid) composition in the biomass and operational conditions. As, Cd, Zn and Pb tend to transform to their gaseous forms at relatively low temperatures (< 1000 °C). Ni, Cu, Mn and Co converts to gaseous forms within the typical gasification temperature range of 1000–1200 °C. Whereas Cr, Al, Fe and Mg remain in solid phase at higher temperatures (> 1200 °C). Simulation of pressurised gasification conditions shows that higher pressures increase the temperature at which solid-to-gaseous phase transformations takes place. - Highlights: • Disposal of plants removed from metal contaminated land raises environmental concerns • Plant samples collected from a contaminated site are shown to contain heavy metals. • Gasification is suitable for plant disposal and its emission is modelled by MTDATA. • As, Cd, Zn and Pb are found in gaseous emissions at a low process temperature. • High pressure gasification can reduce heavy metal elements in process emission.

Persufflation (gaseous oxygen perfusion) as a method of heart preservation.

Science.gov (United States)

Suszynski, Thomas M; Rizzari, Michael D; Scott, William E; Eckman, Peter M; Fonger, James D; John, Ranjit; Chronos, Nicolas; Tempelman, Linda A; Sutherland, David E R; Papas, Klearchos K

2013-04-22

Persufflation (PSF; gaseous oxygen perfusion) is an organ preservation technique with a potential for use in donor heart preservation. Improved heart preservation with PSF may improve outcomes by maintaining cardiac tissue quality in the setting of longer cold ischemia times and possibly increasing the number of donor hearts available for allotransplant. Published data suggests that PSF is able to extend the cold storage times for porcine hearts up to 14 hours without compromising viability and function, and has been shown to resuscitate porcine hearts following donation after cardiac death. This review summarizes key published work on heart PSF, including prospective implications and future directions for PSF in heart transplantation. We emphasize the potential impact of extending preservation times and expanding donor selection criteria in heart allotransplant. Additionally, the key issues that need to be addressed before PSF were to become a widely utilized preservation strategy prior to clinical heart transplantation are summarized and discussed.

Research on solubility characteristics of gaseous methyl iodide

International Nuclear Information System (INIS)

Zhou Yanmin; Sun Zhongning; Gu Haifeng; Wang Junlong

2014-01-01

With the deionized water as the absorbent, the solubility characteristics of the gaseous methyl iodide were studied under different temperature and pressure conditions, using a dynamic measuring method. The results show that within the range of experiment parameters, namely temperature is below 80℃ and pressure is lower than 0.3 MPa, the physical dissolution process of gaseous methyl iodide in water obeys Henry's law. The solubility coefficient under different temperature and pressure conditions was calculated based on the measurement results. Further research indicates that at atmospheric pressure, the solubility coefficient of methyl iodide in water decreases exponentially with the increase of temperature. While the pressure changes from 0.1 MPa to 0.3 MPa with equal interval, the solubility coefficient also increases linearly. The variation of the solubility coefficient with temperature under different pressure conditions all decreases exponentially. An equation is given to calculate the solubility coefficient of methyl iodide under different pressure and temperature conditions. (authors)

Additive Manufacturing Materials Study for Gaseous Radiation Detection

Energy Technology Data Exchange (ETDEWEB)

Steer, C.A.; Durose, A.; Boakes, J. [AWE Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

2015-07-01

Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

Additive Manufacturing Materials Study for Gaseous Radiation Detection

International Nuclear Information System (INIS)

Steer, C.A.; Durose, A.; Boakes, J.

2015-01-01

Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

ASSESSMENT OF THE MOISTURE EFFECT ON GASEOUS PRODUCTS OF SELF-HEATING OF WOOD CHIPS

Directory of Open Access Journals (Sweden)

Hana VĚŽNÍKOVÁ

2017-12-01

Full Text Available Biofuels are stored in large quantities and may be susceptible to self-ignition. The possible methods of indication of temperature increase include the analysis of the gaseous products of heating where concentrations of certain gases may increase with increasing temperature. Gas release is also affected by the moisture of the material given that the moisture level changes surface accessibility for oxygen on the one side and serves as a catalyst of the oxidation reactions on the other. The present project analysed the effect of temperature and moisture on gaseous products of heating of wood chips, one of frequently used biofuels, with the aim to determine a suitable gaseous indicator of beginning self-ignition.

Device for taking gaseous samples from irradiated fuel elements

International Nuclear Information System (INIS)

Lengacker, B.

1983-01-01

The described device allows to take gaseous samples from irradiated fuel elements. It is connected with a gas analyzer and a pressure gage, so that in opening the fuel can the internal pressure can be determined

Gaseous-fuel nuclear reactor research for multimegawatt power in space

Science.gov (United States)

Thom, K.; Schneider, R. T.; Helmick, H. H.

1977-01-01

In the gaseous-fuel reactor concept, the fissile material is contained in a moderator-reflector cavity and exists in the form of a flowing gas or plasma separated from the cavity walls by means of fluid mechanical forces. Temperatures in excess of structural limitations are possible for low-specific-mass power and high-specific-impulse propulsion in space. Experiments have been conducted with a canister filled with enriched UF6 inserted into a beryllium-reflected cavity. A theoretically predicted critical mass of 6 kg was measured. The UF6 was also circulated through this cavity, demonstrating stable reactor operation with the fuel in motion. Because the flowing gaseous fuel can be continuously processed, the radioactive waste in this type of reactor can be kept small. Another potential of fissioning gases is the possibility of converting the kinetic energy of fission fragments directly into coherent electromagnetic radiation, the nuclear pumping of lasers. Numerous nuclear laser experiments indicate the possibility of transmitting power in space directly from fission energy. The estimated specific mass of a multimegawatt gaseous-fuel reactor power system is from 1 to 5 kg/kW while the companion laser-power receiver station would be much lower in specific mass.

PWR-GALE, Radioactive Gaseous Release and Liquid Release from PWR

International Nuclear Information System (INIS)

Chandrasekaran, T.; Lee, J.Y.; Willis, C.A.

1988-01-01

1 - Description of program or function: The PWR-GALE (Boiling Water Reactor Gaseous and Liquid Effluents) Code is a computerized mathematical model for calculating the release of radioactive material in gaseous and liquid effluents from pressurized water reactors (PWRs). The calculations are based on data generated from operating reactors, field tests, laboratory tests, and plant-specific design considerations incorporated to reduce the quantity of radioactive materials that may be released to the environment. 2 - Method of solution: GALE calculates expected releases based on 1) standardized coolant activities derived from ANS Standards 18.1 Working Group recommendations, 2) release and transport mechanisms that result in the appearance of radioactive material in liquid and gaseous waste streams, 3) plant-specific design features used to reduce the quantities of radioactive materials ultimately released to the environs, and 4) information received on the operation of nuclear power plants. 3 - Restrictions on the complexity of the problem: The liquid release portion of GALE uses subroutines taken from the ORIGEN (CCC-217) to calculate radionuclide buildup and decay during collection, processing, and storage of liquid radwaste. Memory requirements for this part of the program are determined by the large nuclear data base accessed by these subroutines

Nuclear waste disposal utilizing a gaseous core reactor

Science.gov (United States)

Paternoster, R. R.

1975-01-01

The feasibility of a gaseous core nuclear reactor designed to produce power to also reduce the national inventories of long-lived reactor waste products through nuclear transmutation was examined. Neutron-induced transmutation of radioactive wastes is shown to be an effective means of shortening the apparent half life.

Deuterium exchange between liquid water and gaseous hydrogen

International Nuclear Information System (INIS)

Dave, S.M.; Ghosh, S.K.; Sadhukhan, H.K.

1982-01-01

The overall separation factors for the deuterium exchange between liquid water and gaseous hydrogen have been calculated over a wide range of temperature, pressure and deuterium concentrations. These data would be useful in the design and other considerations for heavy water production, based on hydrogen-water exchange. (author)

A new gaseous gap conductance relationship

International Nuclear Information System (INIS)

Wesley, D.A.; Yovanovich, M.M.

1986-01-01

A new relationship for predicting the gaseous gap conductance between the fuel and clad of a nuclear fuel rod is derived. This relationship is derived from purely analytical considerations and represents a departure from approaches taken in the past. A comparison between the predictions from this new relationship and experimental measurements is presented and the agreement is very good. Predictions can be generated relatively quickly with this relationship making it attractive for fuel pin analysis codes

EQUILIBRIUM AND KINETIC NITROGEN AND OXYGEN-ISOTOPE FRACTIONATIONS BETWEEN DISSOLVED AND GASEOUS N2O

NARCIS (Netherlands)

INOUE, HY; MOOK, WG

1994-01-01

Experiments were performed to determine the equilibrium as well as kinetic stable nitrogen and oxygen isotope fractionations between aqueous dissolved and gaseous N2O. The equilibrium fractionations, defined as the ratio of the isotopic abundance ratios (15R and 18R, respectively) of gaseous and

Dissolved gaseous mercury and mercury flux measurements in Mediterranean coastal waters: A short review

Directory of Open Access Journals (Sweden)

Fantozzi L.

2013-04-01

Full Text Available There is a general agreement in the scientific community that the marine ecosystem can be a sink and/or source of the mercury that is cycling in the global environment, and current estimates of the global mercury budget for the Mediterranean region are affected by high uncertainty, primarily due to the little progress made so far in evaluating the role of chemical, physical and biological processes in the water system and in the lower atmosphere above the sea water (air-water interface. The lack of knowledge of the magnitude of the air-sea exchange mechanisms is, therefore, one of the main factors affecting the overall uncertainty associated with the assessment of net fluxes of Hg between the atmospheric and marine environments in the Mediterranean region. Results obtained during the last 15 years in the Mediterranean basin indicate the quantitative importance of such emission in the biogeochemical cycle of this element, highlighting the need for thorough investigations on the mechanisms of production and volatilization of dissolved gaseous mercury in waters.

Prediction of External Corrosion for Steel Cylinders--2004 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2004-01-01

Depleted uranium hexafluoride (UF 6 ) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF 6 Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF 6 and the cylinders containing it. This report documents activities that address UF 6 Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in turn to compute

Gaseous radiocarbon measurements of small samples

International Nuclear Information System (INIS)

Ruff, M.; Szidat, S.; Gaeggeler, H.W.; Suter, M.; Synal, H.-A.; Wacker, L.

2010-01-01

Radiocarbon dating by means of accelerator mass spectrometry (AMS) is a well-established method for samples containing carbon in the milligram range. However, the measurement of small samples containing less than 50 μg carbon often fails. It is difficult to graphitise these samples and the preparation is prone to contamination. To avoid graphitisation, a solution can be the direct measurement of carbon dioxide. The MICADAS, the smallest accelerator for radiocarbon dating in Zurich, is equipped with a hybrid Cs sputter ion source. It allows the measurement of both, graphite targets and gaseous CO 2 samples, without any rebuilding. This work presents experiences dealing with small samples containing 1-40 μg carbon. 500 unknown samples of different environmental research fields have been measured yet. Most of the samples were measured with the gas ion source. These data are compared with earlier measurements of small graphite samples. The performance of the two different techniques is discussed and main contributions to the blank determined. An analysis of blank and standard data measured within years allowed a quantification of the contamination, which was found to be of the order of 55 ng and 750 ng carbon (50 pMC) for the gaseous and the graphite samples, respectively. For quality control, a number of certified standards were measured using the gas ion source to demonstrate reliability of the data.

76 FR 53494 - In the Matter of United States Enrichment Corporation; Paducah Gaseous Enrichment Plant...

Science.gov (United States)

2011-08-26

... be filed in accordance with the NRC E-Filing rule (72 FR 49139, August 28, 2007). The E-Filing... the procedural requirements of E-Filing, at least ten (10) days prior to the filing deadline, the... the NRC in accordance with the E-Filing rule, the participant must file the document using the NRC's...

Simplified MPN method for enumeration of soil naphthalene degraders using gaseous substrate.

Science.gov (United States)

Wallenius, Kaisa; Lappi, Kaisa; Mikkonen, Anu; Wickström, Annika; Vaalama, Anu; Lehtinen, Taru; Suominen, Leena

2012-02-01

We describe a simplified microplate most-probable-number (MPN) procedure to quantify the bacterial naphthalene degrader population in soil samples. In this method, the sole substrate naphthalene is dosed passively via gaseous phase to liquid medium and the detection of growth is based on the automated measurement of turbidity using an absorbance reader. The performance of the new method was evaluated by comparison with a recently introduced method in which the substrate is dissolved in inert silicone oil and added individually to each well, and the results are scored visually using a respiration indicator dye. Oil-contaminated industrial soil showed slightly but significantly higher MPN estimate with our method than with the reference method. This suggests that gaseous naphthalene was dissolved in an adequate concentration to support the growth of naphthalene degraders without being too toxic. The dosing of substrate via gaseous phase notably reduced the work load and risk of contamination. The result scoring by absorbance measurement was objective and more reliable than measurement with indicator dye, and it also enabled further analysis of cultures. Several bacterial genera were identified by cloning and sequencing of 16S rRNA genes from the MPN wells incubated in the presence of gaseous naphthalene. In addition, the applicability of the simplified MPN method was demonstrated by a significant positive correlation between the level of oil contamination and the number of naphthalene degraders detected in soil.

Methods for deacidizing gaseous mixtures by phase enhanced absorption

Science.gov (United States)

Hu, Liang

2012-11-27

An improved process for deacidizing a gaseous mixture using phase enhanced gas-liquid absorption is described. The process utilizes a multiphasic absorbent that absorbs an acid gas at increased rate and leads to reduced overall energy costs for the deacidizing operation.

Shuttle Gaseous Hydrogen Venting Risk from Flow Control Valve Failure

Science.gov (United States)

Drummond, J. Philip; Baurle, Robert A.; Gafney, Richard L.; Norris, Andrew T.; Pellett, Gerald L.; Rock, Kenneth E.

2009-01-01

This paper describes a series of studies to assess the potential risk associated with the failure of one of three gaseous hydrogen flow control valves in the orbiter's main propulsion system during the launch of Shuttle Endeavour (STS-126) in November 2008. The studies focused on critical issues associated with the possibility of combustion resulting from release of gaseous hydrogen from the external tank into the atmosphere during assent. The Shuttle Program currently assumes hydrogen venting from the external tank will result in a critical failure. The current effort was conducted to increase understanding of the risk associated with venting hydrogen given the flow control valve failure scenarios being considered in the Integrated In-Flight Anomaly Investigation being conducted by NASA.

Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 2. Draft environmental statement

Energy Technology Data Exchange (ETDEWEB)

Pennington, W. H.

1976-06-01

The need for additional uranium enrichment facilities and the environmental impacts of the add-on gaseous diffusion plant proposed for the Portsmouth Gaseous Diffusion Plant are discussed. A detailed description of the proposed facilities is included and unavoidable adverse environmental effects, possible alternatives, and anticipated benefits from the proposed facilities are considered. The flora and fauna of the area are tabulated and possible effects of air and water pollution on aquatic and terrestrial ecosystems are postulated. The extent of anticipated noise impact on the vicinity and the anticipated extent of civic envolvement are discussed. (CH)

Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 2. Draft environmental statement

International Nuclear Information System (INIS)

1976-06-01

The need for additional uranium enrichment facilities and the environmental impacts of the add-on gaseous diffusion plant proposed for the Portsmouth Gaseous Diffusion Plant are discussed. A detailed description of the proposed facilities is included and unavoidable adverse environmental effects, possible alternatives, and anticipated benefits from the proposed facilities are considered. The flora and fauna of the area are tabulated and possible effects of air and water pollution on aquatic and terrestrial ecosystems are postulated. The extent of anticipated noise impact on the vicinity and the anticipated extent of civic envolvement are discussed

Bench-scale and full-scale studies of nitric oxides reduction by gaseous fuel reburning

International Nuclear Information System (INIS)

Su, S.; Xiang, J.; Sun, L.S.; Hu, S.; Zhu, J.M.

2008-01-01

Nitrogen oxides (NOx) emissions from coal-fired boilers are significant contributors to atmospheric pollution. China has specified more rigorous legal limits for NOx emissions from power plants. As a result of the need to reduce NOx emissions, cost-effective NOx reduction strategies must be explored. This paper presented detailed experimental studies on a gaseous fuel reburning process that was performed in a 36 kilowatt bench-scale down-fired furnace to define the optimal reburning operating conditions when different Chinese coals were fired in the furnace. In addition, the combustion system of a 350 megawatt full-scale boiler was retrofitted according to the experimental results. Finally, the gaseous fuel reburning was applied to the retrofitted full-scale boiler. The purpose of the study was to obtain a better understanding of the influence of the key parameters on nitric oxide (NO) reduction efficiency of the reburning process and demonstrate the gaseous fuel reburning on a 350 MWe coal-fired boiler in China. The paper described the experimental procedure with particular reference to the experimental facility and measurement; a schematic diagram of the experimental system; experimental fuels; and characteristics of coals for the reburning experiments. Results that were presented included influence of reburn zone residence time; influence of gaseous reburn fuel per cent; influence of excess air coefficient; and unburned carbon in fly ash. It was concluded that both an above 50 per cent NO reduction efficiency and low carbon loss can be obtained by the gaseous fuel reburning process under the optimal operating conditions. 20 refs., 5 tabs., 10 figs

Vibration signature analysis of compressors in the gaseous diffusion process for uranium enrichment

International Nuclear Information System (INIS)

Harbarger, W.B.

1975-01-01

Continuous operation of several thousand axial-flow and centrifugal compressors is vital to the gaseous diffusion process for uranium enrichment. Vibration signature analysis using a minicomputer-based Fast Fourier Transform Analyzer is being applied to the evaluation and surveillance of compressor performance at the Portsmouth Gaseous Diffusion Plant. Three areas of application include: (1) new blade design and prototype compressor evaluation; (2) corrective and preventive maintenance of machinery components; and (3) evaluation of machinery health. The present system is being used to monitor signals from accelerometers mounted on the load-bearing housings of 16 on-line compressors. These signals are transmitted by hard-wire to the analyzer for daily monitoring. A program for expansion of this system to monitor more than a thousand compressors and automation of the signature comparison process is planned for all three gaseous diffusion plants operated for the United States Energy Research and Development Administration. (auth)

ORGDP RCRA/PCB

International Nuclear Information System (INIS)

Rodgers, T.

1986-01-01

A dual purpose solid/liquid incinerator is currently being constructed at the Oak Ridge Gaseous Diffusion Plant [ORGDP (K-25)] to destroy uranium contaminated, hazardous organic wastes in compliance with the Toxic Substances Control Act (TSCA) and the Resource Conservation and Recovery Act (RCRA). These wastes are generated by the gaseous diffusion plants in Oak Ridge, TN; Paducah, KY; and Portsmouth, OH. In addition, waste will also be received from the Y-12 Plant, Oak Ridge National Laboratory (ORNL), and the Feed Materials Production Center (FMPC). Destruction of PCBs and hazardous liquid organic wastes will be accomplished in a rotary kiln incinerator with an afterburner. This system was selected after a study of various alternatives which are covered in Report No. X-OE-141. Incineration was chosen because it is dependable, permanent, detoxifies organics, and reduces volume. The rotary kiln incinerator was selected because it can thermally destroy organic constituents of liquids, solids, and sludges to produce an organically inert ash. The incineration system, off-gas treatment system, and related instrumentation and controls are being provided by International Waste Energy Systems (IWES) which is responsible for design, construction, startup, and performance testing

gaseous emissions from some industries at ama industrial complex ...

African Journals Online (AJOL)

user

2015-08-11

Aug 11, 2015 ... air quality standards. Therefore, it is recommended that these companies should determine appropriate control measures to reduce these toxic emissions. Key words: Toxic gaseous emissions, type, concentrations, Ama Industrial Complex, Nigeria. INTRODUCTION. Air pollutants such as carbon dioxide ...

Fast and Slow Precession of Gaseous Debris Disks around Planet-accreting White Dwarfs

Science.gov (United States)

Miranda, Ryan; Rafikov, Roman R.

2018-04-01

Spectroscopic observations of some metal-rich white dwarfs (WDs), believed to be polluted by planetary material, reveal the presence of compact gaseous metallic disks orbiting them. The observed variability of asymmetric, double-peaked emission-line profiles in about half of such systems could be interpreted as the signature of precession of an eccentric gaseous debris disk. The variability timescales—from decades down to 1.4 year (recently inferred for the debris disk around HE 1349–2305)—are in rough agreement with the rate of general relativistic (GR) precession in the test-particle limit. However, it has not been demonstrated that this mechanism can drive such a fast, coherent precession of a radially extended (out to 1 {R}ȯ ) gaseous disk mediated by internal stresses (pressure). Here, we use the linear theory of eccentricity evolution in hydrodynamic disks to determine several key properties of eccentric modes in gaseous debris disks around WDs. We find a critical dependence of both the precession period and radial eccentricity distribution of the modes on the inner disk radius, r in. For small inner radii, {r}in}≲ (0.2{--}0.4) {R}ȯ , the modes are GR-driven, with periods of ≈1–10 year. For {r}in}≳ (0.2{--}0.4) {R}ȯ , the modes are pressure dominated, with periods of ≈3–20 year. Correspondence between the variability periods and inferred inner radii of the observed disks is in general agreement with this trend. In particular, the short period of HE 1349–2305 is consistent with its small r in. Circum-WD debris disks may thus serve as natural laboratories for studying the evolution of eccentric gaseous disks.

Gossip: Gaseous pixels

Science.gov (United States)

Koffeman, E. N.

2007-12-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a 55Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated.

Gossip: Gaseous pixels

Energy Technology Data Exchange (ETDEWEB)

Koffeman, E.N. [Nikhef, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)], E-mail: d77@nikhef.nl

2007-12-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a {sup 55}Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated.

Gossip: Gaseous pixels

International Nuclear Information System (INIS)

Koffeman, E.N.

2007-01-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a 55 Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated

Low temperature gaseous surface hardening of stainless steel

DEFF Research Database (Denmark)

Christiansen, Thomas; Somers, Marcel A. J.

2010-01-01

The present contribution gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanite “layers” on stainless steel are addressed....

Effects of gaseous radioactive nuclides on the design and operation of repositories for spent LWR fuel in rock salt

International Nuclear Information System (INIS)

Jenks, G.H.

1979-12-01

Information relating to the identities and amounts of gaseous radionuclides present in spent LWR fuel and to their release from canistered spent fuel under plausible storage and disposal conditions was assembled, reviewed, and analyzed. Information was also reviewed and analyzed on several other subjects that relate to the integrity of the carbon steel canister in which the spent fuel is to be encapsulated and to the expected rates of transfer of gaseous radionuclides through crushed salt backfill within a disposal room in a reference repository in rock salt. The advantages and disadvantages were considered for several different canister-backfill materials, and recommendations were made regarding preferred materials. Other recommendations relate to encapsulation procedures and specifications and to needs for additional experimental studies. The objective of this work was to provide reference information, conclusions, and recommendations that could be used to establish design and operating conditions and procedures for a bedded salt repository for spent LWR fuel and that could also be used to help evaluate the safety of the repository. The results of this work will also generally apply to spent fuel repositories in domal salt. However, because the domal salt may have little or no brine inclusions within it, there may be little or no possibility that brine will migrate into open spaces around an emplaced canister. Addordingly, some of the concerns that result from the possible occurrence of brine migration in bedded salt may be of no importance in domal salt

Trace emissions from gaseous combustion

Energy Technology Data Exchange (ETDEWEB)

Seebold, J.G. [Chevron Research and Technology Co., Richmond, CA (United States)

2000-07-01

The U.S. Clean Air Act (CAA) was amended in 1990 to include the development of maximum achievable control technology (MACT) emission standards for hazardous air pollutants (HAPs) for certain stationary sources by November 2000. MACT emissions standards would affect process heaters and industrial boilers since combustion processes are a potential source for many air toxins. The author noted that one of the problems with MACT is the lack of a clear solid scientific footing which is needed to develop environmentally responsible regulations. In order to amend some of these deficiencies, a 4-year, $7 million research project on the origin and fate of trace emissions in the external combustion of gaseous hydrocarbons was undertaken in a collaborative effort between government, universities and industry. This collaborative project entitled the Petroleum Environmental Research Forum (PERF) Project 92-19 produced basic information and phenomenological understanding in two important areas, one basic and one applied. The specific objectives of the project were to measure emissions while operating different full-scale burners under various operating conditions and then to analyze the emission data to identify which operating conditions lead to low air toxic emissions. Another objective was to develop new chemical kinetic mechanisms and predictive models for the formation of air toxic species which would explain the origin and fate of these species in process heaters and industrial boilers. It was determined that a flame is a very effective reactor and that trace emissions from a typical gas-fired industry burner are very small. An unexpected finding was that trace emissions are not affected by hydrocarbon gaseous fuel composition, nor by the use of ultra low nitrous oxide burners. 2 refs., 8 figs.

Polarization measurement for internal polarized gaseous targets

International Nuclear Information System (INIS)

Ye Zhenyu; Ye Yunxiu; Lv Haijiang; Mao Yajun

2004-01-01

The authors present an introduction to internal polarized gaseous targets, polarization method, polarization measurement method and procedure. To get the total nuclear polarization of hydrogen atoms (including the polarization of the recombined hydrogen molecules) in the target cell, authors have measured the parameters relating to atomic polarization and polarized hydrogen atoms and molecules. The total polarization of the target during our measurement is P T =0.853 ± 0.036. (authors)

Uranium enrichment export control guide: Gaseous diffusion

Energy Technology Data Exchange (ETDEWEB)

1989-09-01

This document was prepared to serve as a guide for export control officials in their interpretation, understanding, and implementation of export laws that relate to the Zangger International Trigger List for gaseous diffusion uranium enrichment process components, equipment, and materials. Particular emphasis is focused on items that are especially designed or prepared since export controls are required for these by States that are party to the International Nuclear Nonproliferation Treaty.

Developments in gaseous core reactor technology

International Nuclear Information System (INIS)

Diaz, N.J.; Dugan, E.T.

1979-01-01

An effort to characterize the most promising concepts for large, central-station electrical generation was done under the auspices of the Nonproliferation Alternative Systems Assessment Program (NASAP). The two leading candidates were identified from this effort: The Mixed-Flow Gaseous Core Reactor (MFGCR) and the Heterogeneous Gas Core Reactor (HGCR). Key advantages over other nuclear concepts are weighed against the disadvantages of an unproven technology and the cost-time for deployment to make a sound decision on RandD support for these promising reactor alternatives. 38 refs

A high-gain, low ion-backflow double micro-mesh gaseous structure for single electron detection

Science.gov (United States)

Zhang, Zhiyong; Qi, Binbin; Liu, Chengming; Feng, Jianxin; Liu, Jianbei; Shao, Ming; Zhou, Yi; Hong, Daojin; Lv, You; Song, Guofeng; Wang, Xu; You, Wenhao

2018-05-01

Application of micro-pattern gaseous detectors to gaseous photomultiplier tubes has been widely investigated over the past two decades. In this paper, we present a double micro-mesh gaseous structure that has been designed and fabricated for this application. Tests with X-rays and UV laser light indicate that this structure exhibits an excellent gas gain of > 7 × 104 and good energy resolution of 19% (full width at half maximum) for 5.9 keV X-rays. The gas gain can reach up to 106 for single electrons while maintaining a very low ion-backflow ratio down to 0.0005. This structure has good potential for other applications requiring a very low level of ion backflow.

Response of PCB contamination in stream fish to abatement actions at an industrial site

International Nuclear Information System (INIS)

Southworth, G.R.; Peterson, M.J.; McCarthy, J.F.; Milne, G.

1995-01-01

The Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, used large quantities of PCBs in equipment associated with the great electric power requirements of isotopic enrichment of uranium. Historic losses of PCBs in the 1950s and 1960s have left a legacy of contamination at the site. A biological monitoring program implemented in 1987 found PCBs in PGDP effluents and in fish downstream from facility discharges. As a consequence, a fish consumption advisory was posted on Little Bayou Creek by the Commonwealth of Kentucky in 1987, and regulatory discharge limits for PCBs at PGDP were reduced. Monitoring at multiple locations in receiving streams indicated that PGDP discharges were more important than in stream sediment contamination as sources of PCBs to fish. Environmental management and compliance staff at PGDP led an effort to reduce PCB discharges and monitor the effects of those actions. The active discharge of uncontaminated process water to historically PCB-contaminated drainage systems was found to mobilize PCBs into KPDES (Clean Water Act) regulated effluents. Efforts to locate PCB sources within the plant, coupled with improvements in management practices and remedial actions, appear to have been successful in reducing PCB discharges from these sources. Actions included emplacing passive monitors in the plant drainage system to identify this as a chronic source, and consolidating and re-routing effluents to minimize flow through PCB-contaminated channels. As a consequence, PCB contamination in fish in small streams receiving plant discharges decreased 75% over from 1992--1995

Options for Kentucky's Energy Future

Energy Technology Data Exchange (ETDEWEB)

Larry Demick

2012-11-01

Three important imperatives are being pursued by the Commonwealth of Kentucky: ? Developing a viable economic future for the highly trained and experienced workforce and for the Paducah area that today supports, and is supported by, the operations of the US Department of Energy’s (DOE’s) Paducah Gaseous Diffusion Plant (PGDP). Currently, the PGDP is scheduled to be taken out of service in May, 2013. ? Restructuring the economic future for Kentucky’s most abundant indigenous resource and an important industry – the extraction and utilization of coal. The future of coal is being challenged by evolving and increasing requirements for its extraction and use, primarily from the perspective of environmental restrictions. Further, it is important that the economic value derived from this important resource for the Commonwealth, its people and its economy is commensurate with the risks involved. Over 70% of the extracted coal is exported from the Commonwealth and hence not used to directly expand the Commonwealth’s economy beyond the severance taxes on coal production. ? Ensuring a viable energy future for Kentucky to guarantee a continued reliable and affordable source of energy for its industries and people. Today, over 90% of Kentucky’s electricity is generated by burning coal with a delivered electric power price that is among the lowest in the United States. Anticipated increased environmental requirements necessitate looking at alternative forms of energy production, and in particular electricity generation.

Determination of some toxic gaseous emissions at Ama Industrial ...

African Journals Online (AJOL)

Determination of some toxic gaseous emissions at Ama Industrial Complex, Enugu, south eastern Nigeria. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... A study of some gases emitted from three industries at Ama industrial complex, Nigeria, was carried out ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Infrared scintillation: a comparison between gaseous and liquid xenon

International Nuclear Information System (INIS)

Bressi, G.; Carugno, G.; Conti, E.; Del Noce, C.; Iannuzzi, D.

2001-01-01

Light yield and spectrum of infrared (IR) scintillation in Xe are different in gaseous and liquid phases. In gas, the spectrum consists mainly of a broad line centered at 1300 nm. In liquid, light is emitted primarily below 1200 nm and with a lower yield

Long-range global warming impact of gaseous diffusion plant operation

International Nuclear Information System (INIS)

Trowbridge, L.D.

1992-09-01

The DOE gaseous diffusion plant complex makes extensive use of CFC-114 as a primary coolant. As this material is on the Montreal Protocol list of materials scheduled for production curtailment, a substitute must be found. In addition to physical cooling properties, the gaseous diffusion application imposes the unique requirement of chemical inertness to fluorinating agents. This has narrowed the selection of a near-term substitute to two fully fluorinated material, FC-318 and FC-3110, which are likely to be strong, long-lived greenhouse gases. In this document, calculations are presented showing, for a number of plausible scenarios of diffusion plant operation and coolant replacement strategy, the future course of coolant use, greenhouse gas emissions (including coolant and power-related indirect CO 2 emissions), and the consequent global temperature impacts of these scenarios

Process and system for removing sulfur from sulfur-containing gaseous streams

Science.gov (United States)

Basu, Arunabha; Meyer, Howard S.; Lynn, Scott; Leppin, Dennis; Wangerow, James R.

2012-08-14

A multi-stage UCSRP process and system for removal of sulfur from a gaseous stream in which the gaseous stream, which contains a first amount of H.sub.2S, is provided to a first stage UCSRP reactor vessel operating in an excess SO.sub.2 mode at a first amount of SO.sub.2, producing an effluent gas having a reduced amount of SO.sub.2, and in which the effluent gas is provided to a second stage UCSRP reactor vessel operating in an excess H.sub.2S mode, producing a product gas having an amount of H.sub.2S less than said first amount of H.sub.2S.

Radioactive effluents, Portsmouth Gaseous Diffusion Plant, calendar year 1982

International Nuclear Information System (INIS)

Acox, T.A.; Hary, L.F.; Klein, L.S.

1983-03-01

Radioactive discharges from the Portsmouth Gaseous Diffusion Plant are discussed and tabulated. Tables indicate both the location of the discharge and the nuclides discharged. All discharges for 1982 are well below the Radioactive Concentration Guide limits specified in DOE Order 5480.1, Chapter XI. 1 figure

Gaseous material capacity of open plasma jet in plasma spray-physical vapor deposition process

Science.gov (United States)

Liu, Mei-Jun; Zhang, Meng; Zhang, Qiang; Yang, Guan-Jun; Li, Cheng-Xin; Li, Chang-Jiu

2018-01-01

Plasma spray-physical vapor deposition (PS-PVD) process, emerging as a highly efficient hybrid approach, is based on two powerful technologies of both plasma spray and physical vapor deposition. The maximum production rate is affected by the material feed rate apparently, but it is determined by the material vapor capacity of transporting plasma actually and essentially. In order to realize high production rate, the gaseous material capacity of plasma jet must be fundamentally understood. In this study, the thermal characteristics of plasma were measured by optical emission spectrometry. The results show that the open plasma jet is in the local thermal equilibrium due to a typical electron number density from 2.1 × 1015 to 3.1 × 1015 cm-3. In this condition, the temperature of gaseous zirconia can be equal to the plasma temperature. A model was developed to obtain the vapor pressure of gaseous ZrO2 molecules as a two dimensional map of jet axis and radial position corresponding to different average plasma temperatures. The overall gaseous material capacity of open plasma jet, take zirconia for example, was further established. This approach on evaluating material capacity in plasma jet would shed light on the process optimization towards both depositing columnar coating and a high production rate of PS-PVD.

Development and prospects of the new gaseous detector 'Micromegas'

International Nuclear Information System (INIS)

Giomataris, Y.

1998-01-01

We report results obtained with the novel gaseous Micromegas detector (MICRO MEsh GAseous Structure), which is under development at Saclay. A simple theory to explain the advantage of the small amplification gap (50-100 μm) is developed. A set of large detectors was exposed during several months in high-intensity particle beams. Full efficiency and a large plateau has been obtained with a 3 mm conversion gap. With a conversion gap as small as 1 mm the efficiency reaches 96 %. A spatial resolution better then 60 μm has been observed with anode strips of 317 μm pitch. Simulations show that with a pitch of 100 μm and the appropriate gas an accuracy of 10 μm and a time resolution of 1 νs is within reach. This development leads to a new generation of cheap position sensitive detectors which would permit high precision tracking or vertexing close to the interaction region, in very high-rate environments. (author)

High-power laser-metal interactions in pressurized gaseous atmospheres

Energy Technology Data Exchange (ETDEWEB)

Bitelli, G. [ENEA, Centro Ricerche Frascati, Rome (Italy). Dip. Innovazione; Lugomer, S.; Furic, K.; Ivanda, M. [Ruder Boskovic Institute, Zagreb (Croatia); Stipancic, M. [Electrotechnical faculty, Osijek (Croatia); Stubicar, M. [Faculty of natural sciences and mathematics, Zagreb (Croatia); Gamulin, O. [School of medicine, Univ. of Zagreb, Zagreb (Croatia)

1996-09-01

Metal surfaces were irradiated in pressurized gaseous atmospheres by a CO{sub 2} laser beam. The gaseous pressures ranged from 2 atm to 6 atm, the energy density of the light beam was about 20-50 J/cm{sup 2} with a power density {approx} 10{sup 9} W/cm{sup 2} and a pulse duration p 150 ns. In the above conditions some new effects were observed. The laser-material interaction occurred in a highly absorptive plasma regime, meaning that the metal surface was effectively screened from the beam. The interaction ended either with plasma adiabatic expansion, in the case of Mo (in O{sub 2}), Te (in N{sub 2}) and T{sub i} (in N{sub 2}), or with plasma explosion, in the case of T{sub i} (in O{sub 2}). The metal surface properties were studied by means of optical analysis, microhardness tests, X-ray diffraction and Raman backscattering.

Experiments for detection of gaseous Po-210 originated from microbial activity in the environment

International Nuclear Information System (INIS)

Ishimoto, A.; Momoshima, N.

2006-01-01

We attempted to detect gaseous Po-210 (half-life 138d) emitted from organisms in the environment. Gaseous Po-210 was tried to collect in 0.5 M nitric acid solution after passing the atmospheric air through filters and a distilled water bubbler, which would remove aerosols existing in the air. The activity of Po-210 was determined by alpha spectrometry after radiochemical separation and electrolytic deposition of Po-210 on a silver disk. Twenty seven point four mBq of Po-210 was observed when 800 m 3 atmospheric air was sampled. Blank of Po-210 in regents and the sampling system was 4.9-6.8 mBq. The concentration of Po-210 observed in the atmospheric air was, thus about 5 times higher than the background; the results strongly support existence of gaseous Po-210 in the environment. (author)

Remotely operated excavator needs assessment/site visit summary

Energy Technology Data Exchange (ETDEWEB)

Straub, J.; Haller, S.; Worsley, R. [Westinghouse Environmental Management Co. of Ohio, Cincinnati, OH (United States); King, M. [THETA Technology Inc. (United States)

1992-12-02

The Uranium in Soils Integrated Demonstration requested an assessment of soil excavation needs relative to soil remediation. The following list identifies the DOE sites assessed: Mound Laboratory, Paducah Gaseous Diffusion Plant, Portsmouth Gaseous Diffusion Plant, Nevada Test Site, Lawrence Livermore National Laboratory, Rocky Flats Plant, Los Alamos National Laboratory, Sandia National Laboratory, Idaho National Engineering Laboratory, Hanford Site, and Fernald Site. The reviewed sites fall into one or more of the following three categories: production, EPA National Priorities List, or CERCLA (superfund) designation. Only three of the sites appear to have the need for a remotely operated excavator rope. Hanford and Idaho Falls have areas of high-level radioactive contamination either buried or in/under buildings. The Fernald site has a need for remote operated equipment of different types. It is their feeling that remote equipment can be used to remove the health dangers to humans by removing them from the area. Most interviewees stated that characterization technologies needs are more immediate concern over excavation. In addition, the sites do not have similar geographic conditions which would aid in the development of a generic precision excavator. The sites visited were not ready to utilize or provide the required design information necessary to draft a performance specification. This creates a strong case against the development of one type of ROPE for use at these sites. Assuming soil characterization technology/methodology is improved sufficiently to allow accurate and real time field characterization then development of a precision excavator might be pursued based on FEMP needs, since the FEMP`s sole scope of work is remediation. The excavator could then be used/tested and then later modified for other sites as warranted.

Photodetachment in the gaseous, liquid, and solid states of matter

International Nuclear Information System (INIS)

Christophorou, L.G.; Datskos, P.G.; Faidas, H.

1994-01-01

We have made absolute cross section measurements of laser photodetachment of C 6 F - 6 ions embedded in gaseous tetramethylsilane (TMS) and compared the results at low gas densities with measurements in nonpolar liquids and solids. The measurements indicate that the photodetachment cross section of C 6 F - 6 in gaseous TMS is about three times larger than in liquid TMS. This is rationalized by considering the effect of the medium on both the photoabsorption and the autodetachment processes. The photodetachment cross section in both the gas and the liquid exhibits (at least) two maxima due to autodetaching negative ion states. It is argued that these are due to σ*→σ* transitions in C 6 F - 6 . The relative positions of these ''superexcited'' anionic states did not change appreciably in going from the gas to the liquid and the solid, indicating similar influences of the medium on them. As expected, the photodetachment threshold in the condensed phase is shifted to higher energies compared to the gaseous phase. This shift is consistent with recent photoelectron studies of photodetachment of C 6 F - 6 clusters. The present study clearly shows that the photodetachment from negative ions embedded in all states of matter proceeds directly or indirectly via negative ion autodetaching states, and that for nonpolar media, the effect of the medium can be accounted for by considering the macroscopic properties of the medium described by its dielectric constant ε and refractive index n

Sampling and identification of gaseous and particle bounded air pollutants

International Nuclear Information System (INIS)

Kettrup, A.

1993-01-01

Air pollutants are gaseous, components of aerosols or particle bounded. Sampling, sample preparation, identification and quantification of compounds depend from kind and chemical composition of the air pollutants. Quality assurance of analytical data must be guaranted. (orig.) [de

Distribution of gaseous and particulate organic composition during dark α-pinene ozonolysis

Directory of Open Access Journals (Sweden)

A. R. Rickard

2010-03-01

Full Text Available Secondary Organic Aerosol (SOA affects atmospheric composition, air quality and radiative transfer, however major difficulties are encountered in the development of reliable models for SOA formation. Constraints on processes involved in SOA formation can be obtained by interpreting the speciation and evolution of organics in the gaseous and condensed phase simultaneously. In this study we investigate SOA formation from dark α-pinene ozonolysis with particular emphasis upon the mass distribution of gaseous and particulate organic species. A detailed model for SOA formation is compared with the results from experiments performed in the EUropean PHOtoREactor (EUPHORE simulation chamber, including on-line gas-phase composition obtained from Chemical-Ionization-Reaction Time-Of-Flight Mass-Spectrometry measurements, and off-line analysis of SOA samples performed by Ion Trap Mass Spectrometry and Liquid Chromatography. The temporal profile of SOA mass concentration is relatively well reproduced by the model. Sensitivity analysis highlights the importance of the choice of vapour pressure estimation method, and the potential influence of condensed phase chemistry. Comparisons of the simulated gaseous- and condensed-phase mass distributions with those observed show a generally good agreement. The simulated speciation has been used to (i propose a chemical structure for the principal gaseous semi-volatile organic compounds and condensed monomer organic species, (ii provide evidence for the occurrence of recently suggested radical isomerisation channels not included in the basic model, and (iii explore the possible contribution of a range of accretion reactions occurring in the condensed phase. We find that oligomer formation through esterification reactions gives the best agreement between the observed and simulated mass spectra.

Building and commissioning of a setup to study ageing phenomena in gaseous detectors

International Nuclear Information System (INIS)

Abuhoza, A.; Schmidt, H.R.; Biswas, S.; Frankenfeld, U.; Hehner, J.; Schmidt, C.J.

2016-01-01

In high-rate heavy-ion experiments, gaseous detectors encounter big challenges in terms of degradation of their performance due to a phenomenon called ageing. A setup for high precision ageing studies has been constructed and commissioned at the GSI detector laboratory. The setup as well as the gas system have been carefully optimized to reach a high sensitivity for ageing effects. Two different materials have been examined for their influence on gaseous detectors: RTV-3145 and Gerband 705. The details of the construction of the ageing test setup and the test results will be presented.

Building and commissioning of a setup to study ageing phenomena in gaseous detectors

Energy Technology Data Exchange (ETDEWEB)

Abuhoza, A., E-mail: aabuhoza@kacst.edu.sa [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt 64291 (Germany); King Abdulaziz City for Science and Technology (KACST), Riyadh (Saudi Arabia); Goethe-Universität, Frankfurt (Germany); Schmidt, H.R. [Eberhard-Karls-Universität, Tübingen (Germany); Biswas, S. [School of Physical Sciences, National Institute of Science Education and Research, Jatni 752050 (India); Frankenfeld, U.; Hehner, J.; Schmidt, C.J. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt 64291 (Germany)

2016-07-11

In high-rate heavy-ion experiments, gaseous detectors encounter big challenges in terms of degradation of their performance due to a phenomenon called ageing. A setup for high precision ageing studies has been constructed and commissioned at the GSI detector laboratory. The setup as well as the gas system have been carefully optimized to reach a high sensitivity for ageing effects. Two different materials have been examined for their influence on gaseous detectors: RTV-3145 and Gerband 705. The details of the construction of the ageing test setup and the test results will be presented.

Correlation and prediction of gaseous diffusion coefficients.

Science.gov (United States)

Marrero, T. R.; Mason, E. A.

1973-01-01

A new correlation method for binary gaseous diffusion coefficients from very low temperatures to 10,000 K is proposed based on an extended principle of corresponding states, and having greater range and accuracy than previous correlations. There are two correlation parameters that are related to other physical quantities and that are predictable in the absence of diffusion measurements. Quantum effects and composition dependence are included, but high-pressure effects are not. The results are directly applicable to multicomponent mixtures.

Charge amplitude distribution of the Gossip gaseous pixel detector

NARCIS (Netherlands)

Blanco Carballo, V.M.; Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Gromov, V.; Hartjes, F.; Kluit, R.; Koffeman, E.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Timmermans, J.; Visschers, J.L.

2007-01-01

The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few

Model for absorption and release of gaseous materials by forest canopies

International Nuclear Information System (INIS)

Murphy, C.E. Jr.

1976-01-01

A model of the physical processes defining the absorption and release of materials by a forest canopy has been developed. The model deals with the turbulent transport of gaseous materials in the surface boundary layer near the canopy, the turbulent transport in the canopy atmosphere, the transport through the boundary layer near the leaf and soil surface, and the solution of the gaseous materials in intracellular fluids and subsequent diffusion into the leaf cells. The model is used to simulate the uptake of molecular tritium by the forest canopy and the subsequent release of tritiated water. Results of dynamic simulations of tritium uptake and release are compared with data collected at the time of a release of molecular tritium to the atmosphere

Mevva ion source operated in purely gaseous mode

International Nuclear Information System (INIS)

Yushkov, G.Y.; MacGill, R.A.; Brown, I. G.

2003-01-01

We have operated a vacuum arc ion source in such a way as to form beams of purely gaseous ions. The vacuum arc configuration that is conventionally used to produce intense beams of metal ions was altered so as to form gaseous ion beams, with only minimal changes to the external circuitry and no changes at all internally to the ion source. In our experiments we formed beams from oxygen (O + and O 2 + ), nitrogen (N + and N 2 + ), argon (Ar + ) and carbon dioxide (C + , CO 2 + , O + and O 2 + ) at extraction voltage of 2 to 50 kV. We used a pulsed mode of operation, with beam pulses approximately 50 milliseconds long and repetition rate 10 pulses per second, for a duty cycle of about 50%. Downstream ion beam current as measured by a 5 cm diameter Faraday cup was typically 0.5 mA pulse or about 250 (micro)A time averaged. This time averaged beam current is very similar to that obtained for metal ions when the source is operated in the usual vacuum arc mode. Here we describe the modifications made to the source and the results of our investigations

Quantum chemical approach for condensed-phase thermochemistry (IV): Solubility of gaseous molecules

Science.gov (United States)

Ishikawa, Atsushi; Kamata, Masahiro; Nakai, Hiromi

2016-07-01

The harmonic solvation model (HSM) was applied to the solvation of gaseous molecules and compared to a procedure based on the ideal gas model (IGM). Examination of 25 molecules showed that (i) the accuracy of ΔGsolv was similar for both methods, but the HSM shows advantages for calculating ΔHsolv and TΔSsolv; (ii) TΔSsolv contributes more than ΔHsolv to ΔGsolv in the HSM, i.e. the solvation of gaseous molecules is entropy-driven, which agrees well with experimental understanding (the IGM does not show this); (iii) the temperature dependence of Henry's law coefficient was correctly reproduced with the HSM.

Impact of the volume of gaseous phase in closed reactors on ANC results and modelling

Science.gov (United States)

Drapeau, Clémentine; Delolme, Cécile; Lassabatere, Laurent; Blanc, Denise

2016-04-01

The understanding of the geochemical behavior of polluted solid materials is often challenging and requires huge expenses of time and money. Nevertheless, given the increasing amounts of polluted solid materials and related risks for the environment, it is more and more crucial to understand the leaching of majors and trace metals elements from these matrices. In the designs of methods to quantify pollutant solubilization, the combination of experimental procedures with modeling approaches has recently gained attention. Among usual methods, some rely on the association of ANC and geochemical modeling. ANC experiments - Acid Neutralization Capacity - consists in adding known quantities of acid or base to a mixture of water and contaminated solid materials at a given liquid / solid ratio in closed reactors. Reactors are agitated for 48h and then pH, conductivity, redox potential, carbon, majors and heavy metal solubilized are quantified. However, in most cases, the amounts of matrix and water do not reach the total volume of reactors, leaving some space for air (gaseous phase). Despite this fact, no clear indication is given in standard procedures about the effect of this gaseous phase. Even worse, the gaseous phase is never accounted for when exploiting or modeling ANC data. The gaseous phase may exchange CO2 with the solution, which may, in turn, impact both pH and element release. This study lies within the most general framework for the use of geochemical modeling for the prediction of ANC results for the case of pure phases to real phase assemblages. In this study, we focus on the effect of the gaseous phase on ANC experiments on different mineral phases through geochemical modeling. To do so, we use PHREEQC code to model the evolution of pH and element release (including majors and heavy metals) when several matrices are put in contact with acid or base. We model the following scenarios for the gaseous phase: no gas, contact with the atmosphere (open system

Separation of gaseous air pollutants using membrane contactors

Science.gov (United States)

Sverak, T.; Bulejko, P.; Ostrezi, J.; Kristof, O.; Kalivoda, J.; Kejik, P.; Mayerova, K.; Adamcik, M.

2017-10-01

This work deals with the separation of CO2 gaseous pollutant from gas mixtures to a water solution using the laboratory contactor. The laboratory set process parameters showed the rate of carbon dioxide transition through the interface in a so promising level the contactor separators can be considered as a very promising pathway to reduce the content of this greenhouse gas from the air.

Trends and new developments in gaseous detectors

International Nuclear Information System (INIS)

Hoch, M.

2004-01-01

Almost one century ago the method of particle detection with gaseous detectors was invented. Since then they have been exploited successfully in many experiments using a wide variety of different applications. The development is still going on today. The underlying working principles are today well understood and with the help of modern simulation techniques, new configurations can be easily examined and optimized before a first experimental test. Traditional wire chamber ensembles demonstrate that they are still up to date and are well prepared to meet also the challenges of LHC. Applications will be discussed using TPCs in high multiplicity environments with standard Multi-Wire Proportional Chamber (MWPC) as readout as well as drift tubes in a muon spectrometer for a Large Hardron Collider (LHC) experiment. Triggered by the evolving printed circuit technology, a new generation of gaseous detectors with very high position resolution and rate capability has emerged. Two representatives (MICROMEGAS, GEM) have proved their reliability in various experiments and are promising candidates for future projects. Performance and results will be discussed for these detectors. Furthermore, achievements in RPC-based detectors will be discussed. The standard Trigger RPC is a reliable low-cost semi-industrial manufactured device with good time resolution. Thin gap RPCs (Multigap-, and High Rate Timing RPC) show very fast signal response at high efficiency and significantly increased rate capability and will be applied in TOF detectors

Trends and new developments in gaseous detectors

Science.gov (United States)

Hoch, M.

Almost one century ago the method of particle detection with gaseous detectors was invented. Since then they have been exploited successfully in many experiments using a wide variety of different applications. The development is still going on today. The underlying working principles are today well understood and with the help of modern simulation techniques, new configurations can be easily examined and optimized before a first experimental test. Traditional wire chamber ensembles demonstrate that they are still up to date and are well prepared to meet also the challenges of LHC. Applications will be discussed using TPCs in high multiplicity environments with standard Multi-Wire Proportional Chamber (MWPC) as readout as well as drift tubes in a muon spectrometer for a Large Hardron Collider (LHC) experiment. Triggered by the evolving printed circuit technology, a new generation of gaseous detectors with very high position resolution and rate capability has emerged. Two representatives (MICROMEGAS, GEM) have proved their reliability in various experiments and are promising candidates for future projects. Performance and results will be discussed for these detectors. Furthermore, achievements in RPC-based detectors will be discussed. The standard Trigger RPC is a reliable low-cost semi-industrial manufactured device with good time resolution. Thin gap RPCs (Multigap-, and High Rate Timing RPC) show very fast signal response at high efficiency and significantly increased rate capability and will be applied in TOF detectors.

Trends and new developments in gaseous detectors

Energy Technology Data Exchange (ETDEWEB)

Hoch, M. [CERN, Geneva 23 (Switzerland)]. E-mail: michael.hoch@cern.ch

2004-12-11

Almost one century ago the method of particle detection with gaseous detectors was invented. Since then they have been exploited successfully in many experiments using a wide variety of different applications. The development is still going on today. The underlying working principles are today well understood and with the help of modern simulation techniques, new configurations can be easily examined and optimized before a first experimental test. Traditional wire chamber ensembles demonstrate that they are still up to date and are well prepared to meet also the challenges of LHC. Applications will be discussed using TPCs in high multiplicity environments with standard Multi-Wire Proportional Chamber (MWPC) as readout as well as drift tubes in a muon spectrometer for a Large Hardron Collider (LHC) experiment. Triggered by the evolving printed circuit technology, a new generation of gaseous detectors with very high position resolution and rate capability has emerged. Two representatives (MICROMEGAS, GEM) have proved their reliability in various experiments and are promising candidates for future projects. Performance and results will be discussed for these detectors. Furthermore, achievements in RPC-based detectors will be discussed. The standard Trigger RPC is a reliable low-cost semi-industrial manufactured device with good time resolution. Thin gap RPCs (Multigap-, and High Rate Timing RPC) show very fast signal response at high efficiency and significantly increased rate capability and will be applied in TOF detectors.

Uranium deposit removal from the Oak Ridge Gaseous Diffusion Plant K-25 Building

International Nuclear Information System (INIS)

Ladd, L.D.; Stinnett, E.C. Jr.; Hale, J.R.; Haire, M.J.

1993-01-01

The Oak Ridge Gaseous Diffusion Plant went into operation as the first plant to separate uranium by the gaseous diffusion process. It was built during World War II as part of the U.S. Army Corps of Engineers' Manhattan Project. Its war-time code name was K-25, which was also the name of the first uranium separation building constructed at the installation. The K-25 building was considered an engineering miracle at the time of its construction. Built in a U shape ∼1 mile long and 400 ft wide, it housed complex and unique separation equipment. Despite its size and complexity, it was made fully operational within <2 yr after construction began. The facility operated successfully for more than 20 yr until it was placed in a standby mode in 1964. It is now clear the K-25 gaseous diffusion plant will never again be used to enrich uranium. The U.S. Department of Energy, therefore, has initiated a decontamination and decommission program. This paper discusses various procedures and techniques for addressing critical mass, uranium deposits, and safeguards issues

THE INFLUENCE OF SELECTED GASEOUS FUELS ON THE COMBUSTION PROCESS IN THE SI ENGINE

OpenAIRE

FLEKIEWICZ, Marek; KUBICA, Grzegorz

2017-01-01

Summary. This paper presents the results of SI engine tests, carried out for different gaseous fuels. The analysis carried out made it possible to define the correlation between fuel composition and engine operating parameters. The tests covered various gaseous mixtures: methane with hydrogen from 5% to 50% by volume and LPG with DME from 5% to 26% by mass. The first group, considered as low-carbon-content fuels can be characterized by low CO2 emissions. Flammability of hydrogen added in thos...

Transference system of gaseous fluoride compounds for infrared spectrofotometric analysis

International Nuclear Information System (INIS)

Prado, L.

1988-07-01

A vacuum line design for transference of gaseous fluoride compounds involved in the uranium hexafluoride infrared analysis is presented. The text include specific comments about the characteristics of each component and about the possibilities of its acquisition in the national market. (author) [pt

Fabrication of HTR fuel elements by a gaseous impregnation process

International Nuclear Information System (INIS)

Blin, J.C.; Berthier, J.; Devillard, J.

1976-01-01

The results obtained with the gaseous impregnation process are described. The successive steps of the fabrication in their present state of realization are given together with the results obtained after irradiation. A comparison between this process and a classical method is presented

The feasibility of the liberalization of the russian gaseous industry

International Nuclear Information System (INIS)

Locatelli, C.

2002-11-01

This paper deals with the main lines of the russian gaseous industry reform, Gazprom. The historical aspect and the objectives are discussed. After this presentation the author analyzes the uncertainties of the reform implementing, the constraints and the liberalization feasibility. (A.L.B.)

Elementary electron-molecule interactions and negative ion resonances at subexcitation energies and their significance in gaseous dielectrics

International Nuclear Information System (INIS)

Christophorou, L.G.

1977-01-01

Recent knowledge on low-energy (mostly approximately less than 10 eV) electron-molecule interaction processes in dilute and in dense gases is synthesized, discussed, and related to the breakdown strength of gaseous dielectrics. Optimal design of multicomponent gaseous insulators can be made on the basis of such knowledge

Production of gaseous or vaporous fuels from solid carbonaceous materials

Energy Technology Data Exchange (ETDEWEB)

1951-05-16

A process for the production of gaseous or vaporous fuels from solid carbonaceous materials consists of subjecting the materials in separate zones to at least three successive thermal treatments at least two of which are carried out at different temperature levels. The materials being maintained in zones in the form of beds of finely divided particles fluidized by the passage of gases or vapors upwardly there-through, and recovering product vapors or gases overhead. The total hot gaseous or vaporous effluent and entrained solids from one of the zones is passed directly without separation to another of the zones situated closely adjacent to and vertically above the first named zone in the same vessel, and the heat required in at least one of the thermal treatment zones is supplied at least in part as the sensible heat of residual solids transferred from a thermal treatment zone operated at a higher temperature.

Growth of planetisimals in a gaseous ring

International Nuclear Information System (INIS)

Hourigan, K.

1981-01-01

The aggregation of planetesimals in a gaseous ring leads to the development of a dominant body amongst the planetesimal population. The presence of the gas in the form of a differentially rotating ring serves to constrain the orbits of the planetesimals and grains to within a thin toroidal region through the action of gas drag. This situation allows for the efficient aggregation of bodies and, as a result of the low resultant relative velocites, the minimization of collisional fragmentation effects

EURODIF: the uranium enrichment by gaseous diffusion

International Nuclear Information System (INIS)

Rougeau, J.P.

1981-01-01

During the seventies the nuclear power programme had an extremely rapid growth rate which entailed to increase the world uranium enrichment capacity. EURODIF is the largest undertaking in this field. This multinational joint venture built and now operates and enrichment plant using the gaseous diffusion process at Tricastin (France). This plant is delivering low enriched uranium since two years and has contracted about 110 million SWU's till 1990. Description, current activity and prospects are given in the paper. (Author) [pt

Behaviour of gaseous alkali compounds in coal gasification; Kaasumaisten alkaliyhdisteiden kaeyttaeytyminen kivihiilien kaasutuksessa

Energy Technology Data Exchange (ETDEWEB)

Nykaenen, J [Imatran Voima Oy, Vantaa (Finland)

1997-10-01

In this project the behaviour of alkali compounds emitting from CO{sub 2}/O{sub 2}- and airblown gasification are studied. This research project is closely connected to an EU-project coordinated by the Delft University of Technology (DUT). In that project alkali emissions from a 1.6 MW pilot plant will be measured. The results from those measurements will be compared with the calculations performed in this LIEKKI 2 project. The equilibrium calculations show that the major gaseous alkali compounds emitting from combustion and gasification are chlorides and hydroxides. This applies both to air- and CO{sub 2}/O{sub 2}-blown processes. In all the cases studied the concentration of gaseous alkali compounds is determined mainly by the amount of chlorides. The key parameters, with respect to alkali behaviour, are the temperature of the process and chlorine content of the coal. By cooling the gases down to 600 deg C prior to a ceramic filter the alkali concentration can be kept about at 100 ppbv. In combustion, the addition of calcium carbonate increases the amount of gaseous alkali compounds by decreasing the amount of alkali sulphates. In the case of gasification the importance of limestone is negligible. The difference between air- and CO{sub 2}/O{sub 2}-blown processes, in terms of gaseous alkali emissions, is small. This is because CO{sub 2} concentration of the gas does not have a strong impact on alkali chlorides. Furthermore, the effect of CO{sub 2}/O{sub 2}-ratio of the recirculation process is negligible. (orig.)

Office of Environmental Management Uranium Enrichment Decontamination and Decommissioning Fund financial statements, September 30, 1995 and 1994

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-21

The Energy Policy Act of 1992 (Act) requires the Department of Energy to retain ownership and responsibility for the costs of environmental cleanup resulting from the Government`s operation of the three gaseous diffusion facilities located at the K-25 site in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. The Act transferred the uranium enrichment enterprise to the United States Enrichment Corporation (USEC) as of July 1, 1993, and established the Uranium Enrichment Decontamination and Decommissioning Fund (D&D Fund) to: Pay for the costs of decontamination and decommissioning at the diffusion facilities; pay the annual costs for remedial action at the diffusion facilities to the extent that the amount in the Fund is sufficient; and reimburse uranium/thorium licensees for the costs of decontamination, decommissioning, reclamation, and other remedial actions which are incident to sales to the Government.

United States uranium enrichment policies

International Nuclear Information System (INIS)

Roberts, R.W.

1977-01-01

ERDA's uranium enrichment program policies governing the manner in which ERDA's enrichment complex is being operated and expanded to meet customer requirements for separative work, research and development activities directed at providing technology alternatives for future enrichment capacity, and establishing the framework for additional domestic uranium enrichment capacity to meet the domestic and foreign nuclear industry's growing demand for enrichment services are considered. The ERDA enrichment complex consists of three gaseous diffusion plants located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Today, these plants provide uranium enrichment services for commercial nuclear power generation. These enrichment services are provided under contracts between the Government and the utility customers. ERDA's program involves a major pilot plant cascade, and pursues an advanced isotope separation technique for the late 1980's. That the United States must develop additional domestic uranium enrichment capacity is discussed

In situ accretion of gaseous envelopes on to planetary cores embedded in evolving protoplanetary discs

Science.gov (United States)

Coleman, Gavin A. L.; Papaloizou, John C. B.; Nelson, Richard P.

2017-09-01

The core accretion hypothesis posits that planets with significant gaseous envelopes accreted them from their protoplanetary discs after the formation of rocky/icy cores. Observations indicate that such exoplanets exist at a broad range of orbital radii, but it is not known whether they accreted their envelopes in situ, or originated elsewhere and migrated to their current locations. We consider the evolution of solid cores embedded in evolving viscous discs that undergo gaseous envelope accretion in situ with orbital radii in the range 0.1-10 au. Additionally, we determine the long-term evolution of the planets that had no runaway gas accretion phase after disc dispersal. We find the following. (I) Planets with 5 M⊕ cores never undergo runaway accretion. The most massive envelope contained 2.8 M⊕ with the planet orbiting at 10 au. (II) Accretion is more efficient on to 10 M⊕ and 15 M⊕ cores. For orbital radii ap ≥ 0.5 au, 15 M⊕ cores always experienced runaway gas accretion. For ap ≥ 5 au, all but one of the 10 M⊕ cores experienced runaway gas accretion. No planets experienced runaway growth at ap = 0.1 au. (III) We find that, after disc dispersal, planets with significant gaseous envelopes cool and contract on Gyr time-scales, the contraction time being sensitive to the opacity assumed. Our results indicate that Hot Jupiters with core masses ≲15 M⊕ at ≲0.1 au likely accreted their gaseous envelopes at larger distances and migrated inwards. Consistently with the known exoplanet population, super-Earths and mini-Neptunes at small radii during the disc lifetime, accrete only modest gaseous envelopes.

Study on radioactive release of gaseous and liquid effluents during normal operation of AP1000

International Nuclear Information System (INIS)

Gong Quan; Zhou Jing; Liu Yu

2014-01-01

The gaseous and liquid radioactive releases of pressurized water reactors plant during normal operation are an important content of environmental impact assessment and play a significant role in the design of nuclear power plant. According to the design characters of AP1OOO radioactive waste management system and the study on the calculation method and the release pathways, the calculation model of the gaseous and liquid radioactive releases during normal operation for AP1OOO are established. Base on the established calculation model and the design parameters of AP1000, the expected value of gaseous and liquid radioactive releases of AP1OOO is calculated. The results of calculation are compared with the limits in GB 6249-2011 and explain the adder that is included tu account for anticipated operational occurrences, providing a reference for environmental impact assessment of pressurized water reactor. (authors)

Estimation of radionuclide releases in atmosphere from Cernavoda NPP based on continuous gaseous effluent monitoring

International Nuclear Information System (INIS)

Bobric, E.; Murgoci, S.; Popescu, I.; Ibadula, R.

2001-01-01

Monitoring of gaseous effluents from Cernavoda NPP is performed to assess the environmental impact of the plant operation. The results of the monitoring program are used to evaluate the population doses in order to ensure that the emissions of radionuclides in air are below regulatory limits and radiation doses are maintained ALARA. It complements, but is independent from the Operational Environmental Monitoring Program for Cernavoda NPP. Gaseous effluent monitors provide continuous indication of the radioactivity content in atmospheric emissions. Except for noble gases, these monitors also collect samples for later detailed analysis in the station Health Physics Laboratory. This paper presents the main equipment and the results of the gaseous effluents monitoring program in order to assess the impact of Cernavoda NPP operation and to predict the future releases as function of radionuclides concentrations in CANDU systems, based on the identified trends.(author)

Fuel clean-up: poisoning of palladium-silver membranes by gaseous impurities

International Nuclear Information System (INIS)

Chabot, J.; Lecomte, J.; Grumet, C.; Sannier, J.

1988-01-01

The feasibility of a permeation process using a palladium-silver alloy membrane, to separate deuterium and tritium from fusion reactor gaseous wastes needs demonstration owing to poisoning effects of impurities. A parametric investigation of the poisoning by the most important expected gaseous impurities (C0, C0 2 and CH 4 ) is carried out with the loop PALLAS, in function of membrane temperature (100 to 450 0 C), H 2 pressure (0.3 to 14 kPa) and impurity concentration (0.2 to 9.5 vol. %). The poisoning effect of C0 is a concern for the process while C0 2 and CH 4 appear to have no practical effect on the permeation rate. Depending on C0 concentration optimal operating temperatures of the membrane should lie between 250 and 375 0 C limits

Adsorption of gaseous RuO4 by various sorbents. II

International Nuclear Information System (INIS)

Vujisic, L.; Nikolic, R.

1983-01-01

Sorption of gaseous RuO 4 on impregnated Alcoa Alumina H-151, impregnated charcoal, silica gel and HEPA filter was investigated. The results obtained on various sorbents are compared and discussed in connection with possibilities to use the chosen material in air cleaning systems

Gaseous products generated by radiation degradation of N,N-diethylhydroxylamine aqueous solution

International Nuclear Information System (INIS)

Wang Jinhua; Wang Shengxiu; Bao Borong; Li Zhen; Li Chun; Zheng Weifang; Zhang Shengdong

2008-01-01

In this paper, gaseous products generated by radiation degradation of N,N-diethylhydroxylamine (DEHA) in aqueous solution are studied. The results show that by 10-1000 kGy irradiation of the solution in DEHA concentration of 0.1-0.5 mol·L -1 , the gaseous products were mainly hydrogen, methane, ethane and ethene. The volume fraction of hydrogen did not change much with different concentrations of DEHA. The volume fraction of methane and ethane decreased, but that of ethene increased, with increasing DEHA concentration. The volume fraction of hydrogen, methane and ethane increased with the dose. The relationship of the volume fraction of ethene with the dose had something to do with the DEHA concentration. (authors)

Separation of tritium from gaseous and aqueous effluent systems

International Nuclear Information System (INIS)

Kobisk, E.H.

1977-01-01

Three processes are discussed for separating tritium from gaseous and aqueous effluent systems: separation in the gas phase using Pd-25 wt percent Ag alloy diffusion membranes; electrolytic separation in the aqueous phase using ''bipolar'' electrodes; and the countercurrent exchange of tritium-containing hydrogen gas with water on catalytic surfaces combined with separation by direct electrolysis

Distribution of metals between particulate and gaseous forms in a volcanic plume

Science.gov (United States)

Hinkley, T.K.

1991-01-01

In order to gain information on the distribution of metals between particles and gaseous forms in the plume of Kilauea volcano, a filter designed to collect metals associated with particles was followed in series by two other collectors intended to trap metals present in gaseous (atomic, molecular, or complexed) form: first an acid-bubbler bath and then a cold trap. Of the six metals measured, all of the In, Tl and Bi, and almost all of the Cd, Pb and Cu were found on the filter. None of any of the metals was detected in the acid-bubbler bath. Masses equivalent to 0.3% of the amount of Cd on the filter, 0.4% of the amount of Pb, and 9.3% of the Cu, were measured in the cold trap. The results indicate that all or nearly all of the six metals were partitioned to the particulate portion of the physical mixture of gases and particles that constitutes a volcanic plume, but that there may be systematic differences between chalcophile metals in the ways they are partitioned between particulate and gaseous phases in a cooled plume, and possibly differences in the acidity or other chemical properties of the molecular phases. ?? 1991 Springer-Verlag.

EVALUATION OF GASEOUS EMISSIONS FROM THE RĂDĂUŢI MUNICIPAL LANDFILL

Directory of Open Access Journals (Sweden)

Marinela PETRESCU

2011-03-01

Full Text Available Our study presents the evaluation of gaseous emissions generated by a non-compliant municipal landfill after its closure (municipal landfill Rădăuţi. To this end we measured and interpreted the characteristics of gaseous emissions captured in two monitoring boreholes made on the deposit surface (F1 and F2. The main components of landfill gas are CH4 and CO2, and in lower proportions O2, N2 and nitrogen oxides, and also traces of H2S and CO. Their concentrations were measured using a portable gas analyzer GA type 2000Plus, which recorded simultaneously temperature and pressure data of the landfill gas. The high concentration of about 60% CH4 and approximately 39% CO2 in the landfill gas captured in two different areas (F1 and F2 shows the polluting character of those emissions with a direct impact on the environmental component "air", due to the greenhouse effect produced by those two components. Moreover, the characteristics of the measured gaseous emissions (a CH4 content above 50%, a 2-3 l / h flow rate indicates they have significant energy potential and represent a possible source of renewable energy.

Persufflation (or gaseous oxygen perfusion) as a method of organ preservation.

Science.gov (United States)

Suszynski, Thomas M; Rizzari, Michael D; Scott, William E; Tempelman, Linda A; Taylor, Michael J; Papas, Klearchos K

2012-06-01

Improved preservation techniques have the potential to improve transplant outcomes by better maintaining donor organ quality and by making more organs available for allotransplantation. Persufflation, (PSF, gaseous oxygen perfusion) is potentially one such technique that has been studied for over a century in a variety of tissues, but has yet to gain wide acceptance for a number of reasons. A principal barrier is the perception that ex vivo PSF will cause in vivo embolization post-transplant. This review summarizes the extensive published work on heart, liver, kidney, small intestine and pancreas PSF, discusses the differences between anterograde and retrograde PSF, and between PSF and other conventional methods of organ preservation (static cold storage, hypothermic machine perfusion). Prospective implications of PSF within the broader field of organ transplantation, and in the specific application with pancreatic islet isolation and transplant are also discussed. Finally, key issues that need to be addressed before PSF becomes a more widely utilized preservation strategy are summarized and discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Neutron and thermal dynamics of a gaseous core fission reactor

International Nuclear Information System (INIS)

van Dam, H.; Kuijper, J.C.; Stekelenburg, A.J.C.; Hoogenboom, J.E.; Boersma-Klein, W.; Kistemaker, J.

1989-01-01

In this paper neutron kinetics and thermal dynamics of a Gaseous Core Fission Reactor with magnetical pumping are shown to have many unconventional aspects. Attention is focused on the properties of the fuel gas, the non-linear neutron kinetics and the energy balance in thermodynamical cycles

Reactor physics and thermodynamics of a gaseous core fission reactor

International Nuclear Information System (INIS)

Kuijper, J.C.; Van Dam, H.; Stekelenburg, A.J.C.; Hoogenboom, J.E.; Boersma-Klein, W.; Kistemaker, J.

1990-01-01

Neutron kinetics and thermodynamics of a Gaseous Core Fission Reactor with magnetical pumping are shown to have many unconventional aspects. Attention is focussed on the properties of the fuel gas, the stationary temperature distribution, the non-linear neutron kinetics and the energy balance in thermodynamical cycles

Relationship between epiphytic lichens, trace elements and gaseous atmospheric pollutants

NARCIS (Netherlands)

Dobben, van H.F.; Wamelink, G.W.W.; Braak, ter C.J.F.

2001-01-01

A study was conducted to determine the joint effect of gaseous atmospheric pollutants and trace elements on epiphytic lichens. We used our data to test the hypothesis that lichens are generally insensitive to toxic effects of trace elements, and can therefore be used as accumulator organisms to

Chemistry of gaseous lower-valent actinide halides. Technical progress report

International Nuclear Information System (INIS)

Hildenbrand, D.L.

1984-01-01

Objective is to provide thermochemical data for key actinide halide and oxyhalide systems. Progress is reported on bond dissociation energies of gaseous ThCl 4 , ThCl 3 , ThCl 2 , and ThCl; bond dissociation energies of ruthenium fluorides; and mass spectroscopy of UF 6

Liquid and Gaseous Waste Operations Department annual operating report, CY 1995

International Nuclear Information System (INIS)

Maddox, J.J.; Scott, C.B.

1996-03-01

This report describes the operating activities, upgrade activities, maintenance, and other activities regarding liquid and gaseous low level radioactive waste management at the Oak Ridge National Laboratory. Miscellaneous activities include training, audits, tours, and environmental restoration support

Progress in GEM-based gaseous photomultipliers

CERN Document Server

Chechik, R; Breskin, Amos; Buzulutskov, A F; Guedes, G P; Mörmann, D; Singh, B K

2003-01-01

We discuss recent progress in gaseous photomultipliers (GPMTs) comprising UV-to-visible spectral range photocathodes (PCs) coupled to multiple Gas Electron Multipliers (GEM). The PCs may be either semitransparent or reflective ones directly deposited on the first-GEM surface. These detectors provide high gain, even in noble gases, are sensitive to single photons, have nanosecond time resolution, and offer good localization. The operation of CsI-based GPMTs in CF sub 4 opens new applications in Cherenkov detectors, where both the radiator and the photosensor operate in the same gas. The latest results on sealed visible-light detectors, combining bialkali PCs and Kapton-made GEMs are presented.

Thermodynamic properties of cesium in the gaseous phase

International Nuclear Information System (INIS)

Vargaftik, N.B.; Voljak, L.D.; Stepanov, V.G.

1985-01-01

Tables of the thermodynamic properties of caesium in the gaseous phase are presented for a wide range of temperature and pressure. The thermodynamic properties include: enthalpy, entropy, specific heat, specific volume, sound velocity and compressibility factor. The values have been calculated from pressure-volume-temperature measurements by various authors. Experimental apparatus to determine these measurements is described, together with an outline of the method employed to process the results, and the error estimates. (U.K.)

Demister apparatus for gaseous wastes carrying radioactive aerosols

International Nuclear Information System (INIS)

Meline, F.G.; Richter, R.J.

1983-01-01

In the nuclear industry, more precisely in the field of spent fuel reprocessing, the cleaning of the gaseous wastes, before evacuation, should be realized with a device designed in order to take full account of the constraints that are inherent in the radioactive media. The French Atomic Authority (CEA), in collaboration with the Societe Generale pour les Techniques Nouvelles, have studied and developed types of demister for the nuclear field having good cleaning properties

The effect of feeding high fat diet to beef cattle on manure composition and gaseous emission from a feedlot pen surface

Directory of Open Access Journals (Sweden)

Dhan Prasad Gautam

2016-06-01

Full Text Available Abstract Background Dietary manipulation is a common practice to mitigate gaseous emission from livestock production facilities, and the variation of fat level in the diet has shown great influence on ruminal volatile fatty acids (VFA and enteric methane generation. The changes in dietary fat levels influence rumen chemistry that could modify manure nutrient composition along with odor and gaseous emissions from manure management facilities. Methods A field experiment was carried out on beef cattle feedlots to investigate the effect of four levels of dietary fat concentrations (3 to 5.5 % on the manure composition and gaseous emissions (methane-CH4, nitrous oxide-N2O, carbon dioxide-CO2 and hydrogen sulfide-H2S from the feedlot pen surface. The experiment was carried out over a 5-month period from June to October during North Dakota’s summer-fall climatic condition. Air and manure sampling was conducted five times at a 20–30 day intervals. Results Overall, this research indicated that fat levels in diet have no or little effect on the nutrient composition of manure and gaseous emission from the pens with cattle fed with different diet. Though significant variation of gaseous emission and manure composition were observed between different sampling periods, no effect of high fat diet was observed on manure composition and gaseous emission. Conclusions It can be concluded that addition of fat to animal diet may not have any impact on gaseous emission and manure compositions.

The effect of feeding high fat diet to beef cattle on manure composition and gaseous emission from a feedlot pen surface.

Science.gov (United States)

Gautam, Dhan Prasad; Rahman, Shafiqur; Borhan, Md Saidul; Engel, Chanda

2016-01-01

Dietary manipulation is a common practice to mitigate gaseous emission from livestock production facilities, and the variation of fat level in the diet has shown great influence on ruminal volatile fatty acids (VFA) and enteric methane generation. The changes in dietary fat levels influence rumen chemistry that could modify manure nutrient composition along with odor and gaseous emissions from manure management facilities. A field experiment was carried out on beef cattle feedlots to investigate the effect of four levels of dietary fat concentrations (3 to 5.5 %) on the manure composition and gaseous emissions (methane-CH4, nitrous oxide-N2O, carbon dioxide-CO2 and hydrogen sulfide-H2S) from the feedlot pen surface. The experiment was carried out over a 5-month period from June to October during North Dakota's summer-fall climatic condition. Air and manure sampling was conducted five times at a 20-30 day intervals. Overall, this research indicated that fat levels in diet have no or little effect on the nutrient composition of manure and gaseous emission from the pens with cattle fed with different diet. Though significant variation of gaseous emission and manure composition were observed between different sampling periods, no effect of high fat diet was observed on manure composition and gaseous emission. It can be concluded that addition of fat to animal diet may not have any impact on gaseous emission and manure compositions.

Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

International Nuclear Information System (INIS)

Becker, D.L.; Green, D.J.; Lindquist, M.R.

1993-07-01

The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of uranium hexafluoride (UF 6 ). Uranium hexafluoride enriched uranium than 1.0 wt percent 235 U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF 6 cylinders/overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF 6 packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the is documented in Reference 4

Direct measurement of gaseous activities by diffusion-in long proportional counter method

International Nuclear Information System (INIS)

Yoshida, M.; Yamamoto, T.; Wu, Y.; Aratani, T.; Uritani, A.; Mori, C.

1993-01-01

Direct measurement of gaseous activities by the diffusion-in long proportional counter method (DLPC method) was studied. The measuring time without end effect was estimated by observing the behavior of 37 Ar in the counter and was long enough to carry out the accurate activity measurement. The correction for wall effect was also examined on the basis of the measured and calculated correction factors. Among the tested gases of methane, P10 gas and propane, P10 gas was made clear to be a suitable counting gas for the DLPC method because of good diffusion properties and small wall effect. This method is quite effective for standardization of gaseous activities used for tracer experiments and calibration works of radioactive gas monitoring instruments. (orig.)

Gaseous 83mKr generator for KATRIN

Science.gov (United States)

Sentkerestiová, J.; Dragoun, O.; Lebeda, O.; Ryšavý, M.; Sturm, M.; Vénos, D.

2018-04-01

Monoenergetic conversion electrons from the 83mKrKr isomeric state have been proven to be useful in the calibration of several tritium neutrino mass and dark matter experiments. In this paper the design and characteristics of the gaseous 83mKrKr generator, including the 83Rb/83mKrKr source behavior in tritium, for the KATRIN experiment are presented. Using Si(Li) and silicon drift detectors (SDD) detectors, the half-life of the 83mKrKr isomeric state was measured to be 1.8620 ± 0.0019 h.

Transfer of gaseous iodine from atmosphere to rough rice, brown rice and polished rice

International Nuclear Information System (INIS)

Sumiya, Misako; Uchida, Shigeo; Muramatsu, Yasuyuki; Ohmomo, Yoichiro; Yamaguchi, Shuho; Obata, Hitoshi.

1987-01-01

Experiments were carried out in order to obtain information required for establishing transfer coefficients of gaseous iodine (I 2 ) to rough rice, brown rice and polished rice. The gaseous iodine deposited on young rice plants before the heading period was scarcely found in the rough rice harvested at the full ripe stage. The biological half life of iodine in hull, however, was much slower than that in leaves of 14 days. The translocation of iodine from leaves and stalks to rough rice was not clearly recognized. Therefore, it was deduced that iodine found in brown rice mainly should originate from that deposited on the hull. The distribution ratios of iodine between rough rice and brown rice, and between brown rice and polished rice were 100:4 and 100:30 on 100 grains basis, respectively. If average normalized deposition velocity (V d(m) ) or derived deposition velocity (V s ) are given, the transfer coefficients of gaseous iodine to rough rice (TF r ), brown rice (TF b ) and polished rice (TF p ) could be calculated. (author)

Micropore structure stabilization in organosilica membranes by gaseous catalyst post-treatment

NARCIS (Netherlands)

Dral, A. Petra; van Eck, Ernst R.H.; Winnubst, Louis; ten Elshof, Johan E.

2018-01-01

A post-treatment involving repeated exposure to gaseous HCl alternated with heating is demonstrated to strongly accelerate the recently reported structural evolution in organically bridged silica networks. Films, powders and membranes derived from 1,2-bis(triethoxysilyl)ethane were exposed to

Microstructural and compositional Evolution of Compound Layers during Gaseous Nitrocarburizing

DEFF Research Database (Denmark)

Du, Hong; Somers, Marcel A.J.; Ågren, John

2000-01-01

Compound layers developed at 848 K during gaseous nitrocarburizing of iron and iron-carbon specimens were investigated for several combinations of N and C activities imposed at the specimen surface by gas mixtures of NH3, N2, CO2 and CO. The microstructural evolution of the compound layer was stu...

Process for the separation of contaminant or mixture of contaminants from a Ch4-comprising gaseous feed streem

NARCIS (Netherlands)

2012-01-01

The invention provides a process for the separation of a contaminant or mixture of contaminants from a CH4-comprising gaseous feed streem, comprising the subsequent steps of: a) passing a CH4-comprising gaseous feed streem comprising the contaminant or the mixture of contaminants in to and through a

ORGDP RCRA/PCB incinerator facility

International Nuclear Information System (INIS)

Rogers, T.

1987-01-01

A dual purpose solid/liquid incinerator is currently being constructed at the Oak Ridge Gaseous Diffusion Plant [ORGDP (K-25)] to destroy uranium contaminated, hazardous organic wastes in compliance with the Toxic Substances Control Act (TSCA) and the Resource Conservation and Recovery Act (RCRA). These wastes are generated by the gaseous diffusion plants in Oak Ridge, TN; Paducah, KY; and Portsmouth, OH. In addition, waste will also be received from the Y-12 Plant, Oak Ridge National Laboratory (ORNL), and the Feed Materials Production Center (FMPC). Destruction of PCBs and hazardous liquid organic wastes will be accomplished in a rotary kiln incinerator with an afterburner. This system was selected faster a study of various alternatives. Incineration was chosen because it is dependable, permanent, detoxifies organics, and reduces volume. The rotary kiln incinerator was selected because it can thermally destroy organic constituents of liquids, solids, and sludges to produce an organically inert ash. In addition to the incineration off-gas treatment system, the facility includes a tank farm, drum storage buildings, a solids preparation area, a control room, and a data management system. The incineration system, off-gas treatment system, and related instrumentation and controls are being provided by International Waste Energy Systems (IWES) which is responsible for design, construction, startup, and performances testing

Euthanasia using gaseous agents in laboratory rodents.

Science.gov (United States)

Valentim, A M; Guedes, S R; Pereira, A M; Antunes, L M

2016-08-01

Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously. Nevertheless, its aversive potential has been criticized in terms of animal welfare. The data available regarding the use of carbon dioxide (CO2), inhaled anaesthetics (such as isoflurane, sevoflurane, halothane and enflurane), as well as carbon monoxide and inert gases are discussed throughout this review. Euthanasia of fetuses and neonates is also addressed. A table listing currently available information to ease access to data regarding euthanasia techniques using gaseous agents in laboratory rodents was compiled. Regarding better animal welfare, there is currently insufficient evidence to advocate banning or replacing CO2 in the euthanasia of rodents; however, there are hints that alternative gases are more humane. The exposure to a volatile anaesthetic gas before loss of consciousness has been proposed by some scientific studies to minimize distress; however, the impact of such a measure is not clear. Areas of inconsistency within the euthanasia literature have been highlighted recently and stem from insufficient knowledge, especially regarding the advantages of the administration of isoflurane or sevoflurane over CO2, or other methods, before loss of consciousness. Alternative methods to minimize distress may include the development of techniques aimed at inducing death in the home cage of animals. Scientific outcomes have to be considered before choosing the most suitable euthanasia method to obtain the best results and accomplish the 3Rs (replacement, reduction and refinement). © The Author(s) 2015.

DOE Office of Environmental Management, 2016 Year in Review

Energy Technology Data Exchange (ETDEWEB)

None

2016-12-01

2016 accomplishments and primary areas of focus for the Department of Energy's (DOE's) Office of Environmental Management and EM sites are presented. For DOE EM, these include Focusing on the Field, Teaming with Cleanup Partners, Developing New Technology, and Maximizing Cleanup Dollars. Major 2016 achievements are highlighted for EM, Richland Operations Office, Office of River Protection, Savannah River Site, Oak Ridge, Idaho, Waste Isolation Pilot Plant, Los Alamos, Portsmouth, Paducah, West Valley Demonstration Project, and the Nevada National Security Site,

Dynamical behaviour of gaseous halo in a disk galaxy

International Nuclear Information System (INIS)

Ikeuchi, S.; Habe, A.

1981-01-01

Assuming that the gas in the halo of a disk galaxy is supplied from the disk as a hot gas, the authors have studied its dynamical and thermal behaviour by means of a time dependent, two-dimensional hydrodynamic code. They suppose the following boundary conditions at the disk. (i) The hot gas with the temperature Tsub(d) and the density nsub(d) is uniform at r=4-12 kpc in the disk and it is time independent. (ii) This hot gas rotates with the stellar disk in the same velocity. (iii) This hot gas can escape freely from the disk to the halo. These conditions will be verified if the filling factor of hot gas is so large as f=0.5-0.8, as proposed by McKee and Ostriker (1977). The gas motion in the halo has been studied for wider ranges of gas temperature and its density at the disk than previously studied. At the same time, the authors have clarified the observability of various types of gaseous haloes and discuss the roles of gaseous halo on the evolution of galaxies. (Auth.)

The Effect of Gaseous Ozone in Infected Root Canal

Science.gov (United States)

Ajeti, Nova Nexhmije; Pustina-Krasniqi, Teuta; Apostolska, Sonja

2018-01-01

OBJECTIVES: During the treatment of chronic apical periodontitis and pulp necrosis the main role is to irrigate the root canal. AIM: The aim of this in vivo study was to irrigate with 0.9% NaCl (Natrium Chloride), 2.5 % NaOCl (Sodium Hypochlorite Solution, Sigma Aldrich - Germany) and 2% CHX (Chlorhexidine Digluconate Solution, Sigma Aldrich - Spain) combined with Gaseous Ozone (Prozone WH, Austria). MATERIAL AND METHODS: This study was realised in the University Dentistry Clinical Centre of Kosovo (UDCCK), respectively in the Department of Endodontic and Dental Pathology, Dental Branch, Faculty of Medicine, Prishtina, Kosovo. The 40 subjects involved in this study belonged to both genders, in age between 15 -65 years. The sample selection was randomised. The retroalveolar radiography for each patient was taken in the suspected tooth. As a therapeutic plan the authors decided to disinfect the root canal with the irrigants, as follows: 2.5 % NaOCl, 2 % CHX and gaseous ozone. RESULTS: The statistical analyses were based on Kruskal - Vallis test, X - test, DF = 3, r irrigants 0.9%, 2.5 % NaOCl and 2% CHX, it was concluded that the number of colonies of aerobic and anaerobic bacteria was reduced. PMID:29531611

Solid-state photoelectrochemical H2 generation with gaseous reactants

International Nuclear Information System (INIS)

Iwu, Kingsley O.; Galeckas, Augustinas; Kuznetsov, Andrej Yu.; Norby, Truls

2013-01-01

Photocurrent and H 2 production were demonstrated in an all solid-state photoelectrochemical cell employing gaseous methanol and water vapour at the photoanode. Open circuit photovoltage of around −0.4 V and short circuit photocurrent of up to 250 μA/cm 2 were obtained. At positive bias, photocurrent generation was limited by the irradiance, i.e., the amount of photogenerated charge carriers at the anode. Time constants and impedance spectra showed an electrochemical capacitance of the cell of about 15 μF/cm 2 in the dark, which increased with increasing irradiance. With only water vapour at the anode, the short circuit photocurrent was about 6% of the value with gaseous methanol and water vapour. The photoanode and electrocatalyst on carbon paper support were affixed to the proton conducting membrane using Nafion ® as adhesive, an approach that yielded photocurrents up to 15 times better than that of a cell assembled by hot-pressing, in spite of the overall cell resistance of the latter being up to five times less than that of the former. This is attributed, at least partially, to reactants being more readily available at the photoanode of the better performing cell

INDEPENDENT REVIEW OF THE X-701B GROUNDWATER REMEDY, PORTSMOUTH, OHIO: TECHNICAL EVALUATION AND RECOMMENDATIONS

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Eddy-Dilek, C.; Costanza, J.; Rossabi, J.; Early, T.; Skubal, K.; Magnuson, C.

2008-12-15

The Department of Energy Portsmouth Paducah Project Office requested assistance from Department of Energy Office of Environmental Management (EM-22) to provide independent technical experts to evaluate past and ongoing remedial activities at the Portsmouth facility that were completed to address TCE contamination associated with the X-701B groundwater plume and to make recommendations for future efforts. The Independent Technical Review team was provided with a detailed and specific charter. The charter requested that the technical team first review the past and current activities completed for the X-701B groundwater remedy for trichloroethene (TCE) in accordance with a Decision Document that was issued by Ohio EPA on December 8, 2003 and a Work Plan that was approved by Ohio EPA on September 22, 2006. The remedy for X-701B divides the activities into four phases: Phase I - Initial Source Area Treatment, Phase II - Expanded Source Area Treatment, Phase III - Evaluation and Reporting, and Phase IV - Downgradient Remediation and Confirmation of Source Area Treatment. Phase I of the remedy was completed during FY2006, and DOE has now completed six oxidant injection events within Phase II. The Independent Technical Review team was asked to evaluate Phase II activities, including soil and groundwater results, and to determine whether or not the criteria that were defined in the Work Plan for the Phase II end point had been met. The following criteria are defined in the Work Plan as an acceptable Phase II end point: (1) Groundwater samples from the identified source area monitoring wells have concentrations below the Preliminary Remediation Goal (PRG) for TCE in groundwater, or (2) The remedy is no longer effective in removing TCE mass from the source area. In addition, the charter specifies that if the Review Team determines that the Phase II endpoint has not been reached, then the team should address the following issues: (1) If additional injection events are

Gaseous oxygen and hydrogen embrittlements of the uranium-10 weight % molybdenum alloy

International Nuclear Information System (INIS)

Corcos, Jean.

1979-07-01

The stress corrosion of an Uranium-10 weight % Molybdenum alloy in high purity gaseous oxygen and hydrogen was studied. Tests were performed with fracture-mechanic specimens, fatigue precracked and carried out in tension with a constant sustained load. The experimental procedure enabled to determine the S.C. morphology during the test, and its kinetics. Tests in gaseous oxygen were performed with p02=0.15 MPa from 0 0 C to 100 0 C, and at 20 0 C for p02=0.15, 0.15.10 -2 and 0.15.10 -4 MPa. Two kinetic laws are proposed. Cracking is transgranular with a quasi-clivage type, and occurs on the (1 1 1) planes of the matrix. Tests in gaseous hydrogen were performed with pH2=0.15 MPa from - 50 0 C to + 135 0 C; for all the tests, even those under no exterior load, there is a failure by S.C. and macroscopic hydruration occurs. We propose a kinetic law, which may display that the hydruration phenomenon rules the S.C. propagation. We have performed the identification of the hydride, as well as the study of the precipitation. These phenomena don't occur with pH2=0.15.10 -2 MPa. The embrittlement is thought to be due to a formation-failure cycle of an hydride precipitate at the crack tip [fr

Gaseous and air decontamination technologies for Clostridium difficile in the healthcare environment.

Science.gov (United States)

Davies, A; Pottage, T; Bennett, A; Walker, J

2011-03-01

The recent data for hospital-acquired infections suggest that infection rates for meticillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile are beginning to decrease. However, while there is still pressure to maintain this trend, the resistance of C. difficile spores to standard detergents continues to present a problem for many UK hospitals trying to prevent its spread or control outbreaks. Alternative disinfection technologies such as gaseous decontamination are currently being marketed to the healthcare sector as an alternative/supplement to manual disinfection, and have been shown to be effective in reducing environmental contamination. When used correctly, they offer a complementary technology to manual cleaning that increases the probability of an effective reduction in viability and provides a comparatively uniform distribution of disinfectant. Three gaseous decontamination technologies are examined for their suitability in reducing environmental contamination with C. difficile: gaseous hydrogen peroxide, chlorine dioxide and ozone. Air decontamination and UV-based technologies are also briefly described. We conclude that while there is a role to play for these new technologies in the decontamination of ward surfaces contaminated with C. difficile, the requirement for both a preclean before use and the limited 'in vivo' evidence means that extensive field trials are necessary to determine their cost-effectiveness in a healthcare setting. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

Natural sources of gaseous pollutants in the atmosphere

Energy Technology Data Exchange (ETDEWEB)

Altshuller, A P

1958-01-01

Various gaseous pollutants including ozone, nitrous oxide, nitric oxide, nitrogen dioxide, methane, hydrogen, formaldehyde, ammonia, hydrogen sulfide, mercaptans, chlorine compounds and free radicals can be formed by natural processes such as ultraviolet photochemical processes in the upper atmosphere and microbiological processes. The modes of formation and destruction of these gases, especially of their concentrations in the atmosphere, and the various reactions in which these gases can participate with each other are discussed in detail. 114 references.

EFFICIENCY OF PRE-TREATMENT OF LEACHATE FROM MUNICIPAL WASTE DUMPS BY GASEOUS DESORPTION (STRIPPING OF AMMONIA

Directory of Open Access Journals (Sweden)

Justyna Koc-Jurczyk

2017-05-01

Full Text Available The paper studies the efficiency of pre-treatment of landfill leachate by gaseous desorption of ammonia. The research was done on a municipal non-hazardous waste dump in Krosno (Sub-Carpathian Province, Poland. The pretreatment provided a favorable BOD5/COD ratio in leachate. Also concentrations of 16 PAHs and heavy metals did not exceed the legal limits. However, gaseous desorption of ammonia was insufficiently efficient in recovering ammonia nitrogen from leachate.

Liquefied Gaseous Fuels Spill Test Facility

International Nuclear Information System (INIS)

1993-02-01

The US Department of Energy's liquefied Gaseous Fuels Spill Test Facility is a research and demonstration facility available on a user-fee basis to private and public sector test and training sponsors concerned with safety aspects of hazardous chemicals. Though initially designed to accommodate large liquefied natural gas releases, the Spill Test Facility (STF) can also accommodate hazardous materials training and safety-related testing of most chemicals in commercial use. The STF is located at DOE's Nevada Test Site near Mercury, Nevada, USA. Utilization of the Spill Test Facility provides a unique opportunity for industry and other users to conduct hazardous materials testing and training. The Spill Test Facility is the only facility of its kind for either large- or small-scale testing of hazardous and toxic fluids including wind tunnel testing under controlled conditions. It is ideally suited for test sponsors to develop verified data on prevention, mitigation, clean-up, and environmental effects of toxic and hazardous gaseous liquids. The facility site also supports structured training for hazardous spills, mitigation, and clean-up. Since 1986, the Spill Test Facility has been utilized for releases to evaluate the patterns of dispersion, mitigation techniques, and combustion characteristics of select materials. Use of the facility can also aid users in developing emergency planning under US P.L 99-499, the Superfund Amendments and Reauthorization Act of 1986 (SARA) and other regulations. The Spill Test Facility Program is managed by the US Department of Energy (DOE), Office of Fossil Energy (FE) with the support and assistance of other divisions of US DOE and the US Government. DOE/FE serves as facilitator and business manager for the Spill Test Facility and site. This brief document is designed to acquaint a potential user of the Spill Test Facility with an outline of the procedures and policies associated with the use of the facility

Portsmouth gaseous diffusion plant environmental monitoring report for calendar year 1975

International Nuclear Information System (INIS)

Martin, W.E.; Netzer, W.D.

1976-01-01

At the Portsmouth Gaseous Diffusion Plant the ambient atmosphere and all effluent streams are sampled and analyzed regularly for conformance to applicable environmental standards. Although neither the State of Ohio nor the federal government has established standards for fluorides in the ambient atmosphere or in vegetation, these parameters also are monitored because fluoride compounds are used extensively in the gaseous diffusion process. Radioactivity is measured in air, water, food, soil, and sediments; and radiation doses are calculated for the public. All public radiation doses are well within federal standards. Non-radioactive effluent parameters either comply with federal standards, or there are projects planned to allow compliance. A disposal facility to remove chromium from recirculating cooling water blowdown will begin operation in June 1976. Also, pH adjustment facilities for liquid effluents and electrostatic precipitators for a coal-fired steam plant are planned for the near future

Studies of gaseous multiplication coefficient in isobutane using a resistive plate chamber

Energy Technology Data Exchange (ETDEWEB)

Goncalves, Josemary A.C.; Botelho, Suzana; Tobias, Carmen C.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Pontificia Univ. Catolica de Sao Paulo (PUC/SP), SP (Brazil); Lima, Iara B.; Vivaldini, Tulio C. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ridenti, Marco A.; Pascholati, Paulo R. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Fisica. Lab. do Acelerador Linear; Fonte, Paulo; Mangiarotti, Alessio [Universidade de Coimbra (Portugal). Dept. de fisica. Lab. de Instrumentacao e Fisica Experimental de Particulas

2009-07-01

Full text: Due to the increasing demands concerning High Energy Physics, Nuclear Medicine and other Nuclear Applications about gaseous detectors operating in high electric fields, many efforts have been done about the choice of filling gases that fulfill these requirements. In this context, the electron transport parameters in gases, as the gaseous multiplication coefficient, play an important role not only for detector design but also for simulation and modeling of discharges, allowing the validation of electron impact cross-sections. In the present work the preliminary measurements of gaseous multiplication coefficient, as function of the reduced electric field (from 36V/cm.Torr until 93V/cm.Torr), for isobutane are presented. Among several filling gases, isobutane is widely used in resistive plate chambers RPCs, and other gaseous detectors, due to its timing properties. Although its characteristics, there is a lack of swarm parameters data in literature for this gas, mainly at high electric fields. The experimental method used is based on the Pulsed Townsend technique, which follows from Townsend equation solution for a uniform electric field. Considering the ratio between the current (I), measured in avalanche mode, and the primary ionization current (I{sub 0}), the effective multiplication coefficient can be determined, since alpha = d{sup -1}ln(I/I{sub 0}), where d is the gap between the electrodes. In our configuration, the experimental setup consists of two parallel plates enclosure in a stainless steel chamber at gas flow regime. The anode, is made of a high resistivity (2.10{sup 12}{omega}.cm) glass (3mm thick and 14mm diameter), while the cathode is of aluminium (40mm diameter). Primary electrons are produced by irradiating the cathode with a nitrogen laser (LTB MNL200-LD) and are accelerated toward the anode by means of a high voltage power supply (Bertan 225-30). In order to validate the technique and to analyze effects of non-uniformity, results for

First characterization of the endocrine-disrupting potential of indoor gaseous and particulate contamination: comparison with urban outdoor air (France).

Science.gov (United States)

Oziol, Lucie; Alliot, Fabrice; Botton, Jérémie; Bimbot, Maya; Huteau, Viviane; Levi, Yves; Chevreuil, Marc

2017-01-01

The composition of endocrine-disrupting compounds (EDCs) in the ambient air of indoor environments has already been described, but little is known about the inherent endocrine-disrupting potential of indoor air contamination. We therefore aimed to study the distribution of bioactive EDCs in the gaseous and particulate phases of indoor air using a cellular bioassay approach that integrates the interaction effects between chemicals. Organic air extracts, both gaseous and particulate, were taken from three indoor locations (office, apartment, and children's day care) in France and sampled in two different seasons in order to study their interference with the signaling of estrogen, androgen, and thyroid receptors. The experiments were also conducted on aerial extracts from an outdoor site (urban center). We found that gaseous and/or particulate extracts from all locations displayed estrogenicity, anti-androgenicity, and thyroidicity. Overall, indoor air extracts had a higher endocrine-disrupting potential compared to outdoor ones, especially during winter and in the day care. The biological activities were predominant for the gaseous extracts and tended to increase for the particulate extracts in cool conditions. In conclusion, our data confirmed the presence of bioactive EDCs in a gaseous state and highlighted their indoor origin and concentration, especially in the cold season.

Transfer of gaseous iodine to Tradescantia

International Nuclear Information System (INIS)

Nakamura, Yuji; Ohmomo, Yoichiro.

1984-01-01

Transfer rates of gaseous elemental iodine and methyliodide from atmosphere to Tradescantia were investigated in relation to supposed genetic mutation due to radioactive iodine released from nuclear facilities. The estimated transfer rate of elemental iodine to the young buds of Tradescantia, which was given as the ratio of iodine uptake rate per unit weight of the plant to the concentration of the element in the air, was approximately 7 x 10 -2 cm 3 /g.sec, about 30 to 40 times higher than that of methyliodide. The contribution of direct deposition of elemental iodine was suggested to be significant, although methyliodide was mainly absorbed by respiration through stomata of the plant. (author)

Prediction of External Corrosion for Steel Cylinders--2004 Report

Energy Technology Data Exchange (ETDEWEB)

Schmoyer, RLS

2004-07-07

Depleted uranium hexafluoride (UF{sub 6}) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF{sub 6} Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF{sub 6} and the cylinders containing it. This report documents activities that address UF{sub 6} Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in

Diffusion coefficients of gaseous scavengers in organic liquids used in radiation chemistry

International Nuclear Information System (INIS)

Luthjens, L.H.; De Leng, H.C.; Warman, J.M.; Hummel, A.

1990-01-01

Diffusion coefficients have been measured of some gaseous scavengers commonly used in radiation chemical studies: CO 2 , NH 3 , SF 6 and O 2 in trans-decalin, cyclohexane, isooctane and n-hexane, and CO 2 in cis-decalin, at 25 0 C. A modified diaphragm cell method has been used in order to limit the time needed for a measurement to about 6 h. Analysis of the results yields a simple semi-empirical predictive relation for the diffusion coefficient of a (gaseous) solute A in an organic solvent B. Diffusion coefficients calculated using the simple relation appear to give results in fair agreement with published values, over a range of organic solvents including alcohols, and over a range of temperatures. Some measured and predicted values are discussed with reference to results from the literature. (author)

Starlight excitation of permitted lines in gaseous nebulae

International Nuclear Information System (INIS)

Grandi, S.A.

1975-01-01

The weak heavy element permitted lines observed in the spectra of gaseous nebula have, with only a few exceptions, been thought to be excited only by recombination. The accuracy of this assumption for individual lines in nebula spectra is investigated in detail via model nebula calculations. First, approximations and techniques of calculation are considered for the three possible excitation mechanisms: recombination, resonance fluorescence by the starlight continuum, and resonance fluorescence by other nebular emission lines. Next, the permitted lines of O I as observed in gaseous nebulae are discussed. Thirdly, it is shown that varying combinations of recombination, resonance fluorescence by starlight, and resonance fluorescence by other nebula lines can successfully account for the observed strengths in the Orion Nebula of lines of the following ions: C II, N I, N II, N III, O II, Ne II, Si II, Si III, and S III. A similar analysis is performed for the lines in the spectra of the planetary nebulae NGC7662 and NGC7027, and, with some exceptions, satisfactory agreement between the observed and predicted line strengths is found. Finally, observations of the far red spectra of the Orion Nebula, the planetary nebulae NGC3242, NGC6210, NGC2392, IC3568, IC4997, NGC7027, and MGC7662, and the reflection nebulae IC431 and NGC2068 are reported

Absorption of gaseous iodine by water droplets

International Nuclear Information System (INIS)

Albert, M.F.

1985-07-01

A new model has been developed for predicting the rate at which gaseous molecular iodine is absorbed by water sprays. The model is a quasi-steady state mass transfer model that includes the iodine hydrolysis reactions. The parameters of the model are spray drop size, initial concentration of the gas and liquid phases, temperature, pressure, buffered or unbuffered spray solution, spray flow rate, containment diameter and drop fall height. The results of the model were studied under many values of these parameters. Plots of concentration of iodine species in the drop versus time have been produced by varying the initial gas phase concentration of molecular iodine over the range of 1 x 10 -5 moles/liter to 1 x 10 -10 moles/liter and a drop size of 1000 microns. Results from the model are compared to results available from Containment Systems Experiments at Pacific Northwest Laboratory. The difference between the model predictions and the experimental data ranges from -120.5% to 68.0% with the closest agreement 7.7%. The new spray model is also compared to previously existing spray models. At high concentrations of gaseous molecular iodine, the new spray model is considered to be less accurate but at low concentrations, the new model predicts results that are closer to the experimental data than the model called the realistic model from WASH-1329. Inclusion of the iodine hydrolysis reaction is shown to be a feature important to a model intended for determining the removal of molecular iodine over a wide range of conditions

Characterization of additives typically employed in EPDM formulations by using FT-IR of gaseous pyrolyzates

Directory of Open Access Journals (Sweden)

Natália Beck Sanches

2014-06-01

Full Text Available In this study, Fourier transform infrared spectroscopy (FT-IR was employed to investigate the gaseous pyrolysis products of ethylene - propylene - diene rubber (EPDM. The objective was to evaluate the potential of FT-IR analysis of gaseous pyrolyzates (PY-G/FT-IR for characterization of EPDM additives. Two EPDM formulations, containing additives typically employed in EPDM rubbers, were analyzed. Initially, gaseous pyrolysis products from paraffin oil, stearic acid, 2,2,4-trimethyl-1,2-dihydroquinoline, tetramethylthiuram monosulfide (TMTM, tetramethylthiuram disulfide (TMTD, and 2-mercaptobenzothiazole (MBT were characterized separately, and their main absorptions were identified. Subsequently, the gaseous pyrolysis products of raw, unvulcanized, and vulcanized EPDM formulations were analyzed. The similarities observed in the FT-IR spectra of unvulcanized and vulcanized EPDM show that the vulcanization process does not interfere with the pyrolysis products. The identification of the functional groups of the studied additives was possible in both unvulcanized and vulcanized EPDM samples, without solvent extraction. Results also demonstrate that the PY-G/FT-IR technique can identify additives containing sulfur in concentrations as low as 1.4 phr (1.26% in both unvulcanized and vulcanized EPDM. However, the method showed some limitation due to overlapping and to similarities of TMTM and TMTD PY-G/FT-IR spectra, which could not be distinguished from each other. The PY-G/FT-IR technique is a faster and cheaper alternative to the sophisticated techniques usually applied to detection of additives in rubbers.

An aerial radiological survey of the Portsmouth Gaseous Diffusion Plant and surrounding area, Portsmouth, Ohio

International Nuclear Information System (INIS)

1992-09-01

An aerial radiological survey was conducted from July 11--20, 1990, over an 83-square-kilometer (32-square-mile) area surrounding the Portsmouth Gaseous Diffusion Plant located near Portsmouth, Ohio. The survey was conducted at a nominal altitude of 91 meters (300 feet) with line spacings of 122 meters (400 feet). A contour map of the terrestrial gamma exposure rate extrapolated to 1 meter above ground level (AGL) was prepared and overlaid on an aerial photograph and a set of United States Geological Survey (USGS) topographic maps of the area. The terrestrial exposure rates varied from about 7 to 14 microroentgens per hour (μR/h) at 1 meter above the ground. Analysis of the data for man-made sources and for the uranium decay product, protactinium-234m ( 234m Pa), showed five sites within the boundaries of the Portsmouth Gaseous Diffusion Plant with elevated readings. Spectra obtained in the vicinity of the buildings at the Portsmouth Gaseous Diffusion Plant showed the presence of 234m Pa, a uranium-238 ( 238 U) decay product. In addition, spectral analysis of the data obtained over the processing plant facility showed gamma activity indicative of uranium-235 ( 234 U). No other man-made gamma ray emitting radioactive material was detected, either on or off the Portsmouth Gaseous Diffusion Plant property. Soil samples and pressurized ion chamber measurements were obtained at five different locations within the survey boundlaries to support the aerial data

Gaseous photomultipliers for the readout of scintillators and detection Cherenkov radiation

International Nuclear Information System (INIS)

Peskov, V.; Borovik-Romanov, A.

1993-11-01

The latest achievements in the development of gaseous detectors for registering UV and visible photons are described. Possible modifications of their design for some particular applications such as the readout of crystal scintillators. noble liquids, fibers and for large area Cherenkov detectors are discussed

Strategies to reduce gaseous KCl and chlorine in deposits during combustion of biomass in fluidised bed boilers

Energy Technology Data Exchange (ETDEWEB)

Kassman, Haakan

2012-11-01

Combustion of a biomass with an enhanced content of alkali and chlorine (Cl) can result in operational problems including deposit formation and superheater corrosion. The strategies applied to reduce such problems include co-combustion and the use of additives. In this work, measures were investigated in order to decrease the risk of superheater corrosion by reducing gaseous KCl and the content of chlorine in deposits. The strategies applied were sulphation of KCl by sulphur/sulphate containing additives (i.e. elemental sulphur (S) and ammonium sulphate (AS)) and co-combustion with peat. Both sulphation of KCl and capture of potassium (K) in ash components can be of importance when peat is used. The experiments were mainly performed in a 12 MW circulation fluidised bed (CFB) boiler equipped for research purposes but also in a full-scale CFB boiler. The results were evaluated by means of IACM (on-line measurements of gaseous KCl), conventional gas analysis, deposit and corrosion probe measurements and ash analysis. Ammonium sulphate performed significantly better than elemental sulphur. Thus the presence of SO{sub 3} (i.e. AS) is of greater importance than that of SO{sub 2} (i.e. S) for sulphation of gaseous KCl and reduction of chlorine in deposits. Only a minor reduction of gaseous KCl was obtained during co-combustion with peat although chlorine in the deposits was greatly reduced. This reduction was supposedly due to capture of K by reactive components from the peat ash in parallel to sulphation of KCl. These compounds remained unidentified. The effect of volatile combustibles on the sulphation of gaseous KCl was investigated. The poorest sulphation was attained during injection of ammonium sulphate in the upper part of the combustion chamber during the lowest air excess ratio. The explanation for this is that SO{sub 3} was partly consumed by side reactions due to the presence of combustibles. These experimental results were supported by modelling, although the

Cytogenetic effects of the gaseous phase of cigarette smoke on root-tip cells of Allium sativum L

Energy Technology Data Exchange (ETDEWEB)

Pandey, K.N.; Benner, J.F.; Sabharwal, P.S.

1978-02-01

Chromosomal and mitotic abnormalities induced by the gaseous phase of cigarette smoke on the root-tips of garlic, Allium sativum L., were investigated. Chromosomal abnormalities in the form of breakages, bridges, lags, stickiness, and differential condensation were observed. In addition, multinucleate cells, polyploid cells, and multipolar mitotic divisions were observed. In general the results indicate that the percentage of abnormalities increased when root-tips were exposed to higher numbers of smoke puffs. The effect of the gaseous phase of cigarette smoke on the mitotic index is striking. It shows a slight increase at a low number of puffs and a decrease at high numbers, particularly at the 10, 15 and 20 puff levels. The results indicate that the gaseous phase of cigarette smoke induces significant effects on chromosome structure and number.

Gaseous Detector with Sub-keV Threshold to Study Neutrino Scattering at Low Recoil Energies

International Nuclear Information System (INIS)

Solomatin, A. E.; Petukhov, V. V.; Kopylov, A. V.; Orekhov, I. V.

2014-01-01

Gaseous detector with a sub-keV electron equivalent threshold is a very perspective tool for the precision measurement of the neutrino magnetic moment and for observing coherent scattering of neutrinos on nuclei. The progress in the development of low noise electronics makes it possible to register the rare events at the threshold less than 100 eV. The construction of the gaseous detector is given and the typical pulses with amplitudes of a few eV observed on a bench scale installation are presented. The possible implications for future experiments are discussed

Methodology for assessment of safety risk due to potential accidents in US gaseous diffusion plants

International Nuclear Information System (INIS)

Turner, J.H.; O'Kain, D.U.

1991-01-01

Gaseous diffusion plants that operate in the United States represent a unique combination of nuclear and chemical hazards. Assessing and controlling the health, safety, and environmental risks that can result from natural phenomena events, process upset conditions, and operator errors require a unique methodology. Such a methodology has been developed for the diffusion plants and is being utilized to assess and control the risk of operating the plants. A summary of the methodology developed to assess the unique safety risks at the US gaseous diffusion plants is presented in this paper

Treatment of gaseous and airborne radioactive waste

International Nuclear Information System (INIS)

Leichsenring, C.H.

1982-01-01

Gaseous and airborne radionuclides in the fuel cycle are retained in vessel off-gas filter systems and in the dissolver off-gas cleaning system. Those systems have to meet the regulatory requirements for both normal and accident conditions. From the solutions liquid aerosols are formed during liquid transfer (air lifts, steam jets) or by air sparging or by evaporation processes. During dissolution the volatile radionuclides i.e. 85 Kr, 129 I and 14 C are liberated and enter into the dissolver off-gas cleaning system. Flow sheets of different cleaning systems and their stage of development are described. (orig./RW)

Gaseous Mediators Nitric Oxide and Hydrogen Sulfide in the Mechanism of Gastrointestinal Integrity, Protection and Ulcer Healing

Directory of Open Access Journals (Sweden)

Marcin Magierowski

2015-05-01

Full Text Available Nitric oxide (NO and hydrogen sulfide (H2S are known as biological messengers; they play an important role in human organism and contribute to many physiological and pathophysiological processes. NO is produced from l-arginine by constitutive NO synthase (NOS and inducible NOS enzymatic pathways. This gaseous mediator inhibits platelet aggregation, leukocyte adhesion and contributes to the vessel homeostasis. NO is known as a vasodilatory molecule involved in control of the gastric blood flow (GBF and the maintenance of gastric mucosal barrier integrity in either healthy gastric mucosa or that damaged by strong irritants. Biosynthesis of H2S in mammals depends upon two enzymes cystathionine-β-synthase and cystathionine γ-lyase. This gaseous mediator, similarly to NO and carbon monoxide, is involved in neuromodulation, vascular contractility and anti-inflammatory activities. For decades, H2S has been known to inhibit cytochrome c oxidase and reduce cell energy production. Nowadays it is generally considered to act through vascular smooth muscle ATP-dependent K+ channels, interacting with intracellular transcription factors and promote sulfhydration of protein cysteine moieties within the cell, but the mechanism of potential gastroprotective and ulcer healing properties of H2S has not been fully explained. The aim of this review is to compare current results of the studies concerning the role of H2S and NO in gastric mucosa protection and outline areas that may pose new opportunities for further development of novel therapeutic targets.

United States Department of Energy, Office of Environmental Management, Uranium Enrichment Decontamination and Decomissioning Fund financial statements, September 30, 1996 and 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

The Energy Policy Act of 1992 (Act) established the Uranium Enrichment Decontamination and Decommissioning Fund (D and D Fund, or Fund) to pay the costs for decontamination and decommissioning three gaseous diffusion facilities located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio (diffusion facilities). The Act also authorized the Fund to pay remedial action costs associated with the Government`s operation of the facilities and to reimburse uranium and thorium licensees for the costs of decontamination, decommissioning, reclamation, and other remedial actions which are incident to sales to the Government. The report presents the results of the independent certified public accountants` audit of the D and D Fund financial statements as of September 30, 1996. The auditors have expressed an unqualified opinion on the 1996 statement of financial position and the related statements of operations and changes in net position and cash flows.

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

Energy Technology Data Exchange (ETDEWEB)

1977-09-01

Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters. (LK)

Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

International Nuclear Information System (INIS)

1977-09-01

Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters

Method for the removal of a gaseous fluid and arrangement therefore

NARCIS (Netherlands)

Ursem, W.N.J.; Marijnissen, J.C.M.

2011-01-01

The invention provides a method for the removal of a gaseous fluid comprising (a) applying an electric field between a first electrode arranged to generate a corona discharge and a second electrode, comprising a haze-permeable electrically conductive sieve of a plurality of conductive strands, (b)

A radioactive noble gas quantitative analysis of gaseous effluents from NPP

International Nuclear Information System (INIS)

Yanev, Y.; Georgiev, K.; Mavrodiev, V.; Kikarin, B.

1993-01-01

The radioactive isotopes of argon, krypton and xenon comprise a substantial part of the gaseous emission of a NPP. A quantitative determination of their specific activity in the controlled area and the gaseous effluents requires a special sampling technique, as well as measurement method. The zeolites and the activated charcoals have a differentiated behaviour towards radioisotopes of argon, krypton and xenon. The isotope fractionation is often a problem, especially with argon and xenon. Some additional difficulties arise due to the irreproductibility of temperature and atmospheric moisture. The present paper describes a method for a spectrometric determination of radioactive noble gases after the cryogenic sampling developed at the Radiochemical laboratory of the Sofia University. The quality control of the method, as well as some special difficulties in its performing are discussed. The estimated minimum detectable activity is 5-10 Bq/m 3 for radioactive noble gases with half-life > 1 hour and sampling time for (resp. gamma-spectrometry) 1 hour. (author)

A Study of the Operation of Especially Designed Photosensitive Gaseous Detectors at Cryogenic Temperatures

CERN Document Server

Periale, L; Lund-Jensen, B; Pavlopoulos, P; Peskov, Vladimir; Picchi, P; Pietropaolo, F

2006-01-01

In some experiments and applications there is need for large-area photosensitive detectors to operate at cryogenic temperatures. Nowadays, vacuum PMs are usually used for this purpose. We have developed special designs of planar photosensitive gaseous detectors able to operate at cryogenic temperatures. Such detectors are much cheaper PMs and are almost insensitive to magnetic fields. Results of systematic measurements of their quantum efficiencies, the maximum achievable gains and long-term stabilities will be presented. The successful operation of these detectors open realistic possibilities in replacing PMs by photosensitive gaseous detectors in some applications dealing with cryogenic liquids; for example in experiments using noble liquid TPCs or noble liquid scintillating calorimeters.

Seasonal and diurnal variation in concentrations of gaseous and particulate phase endosulfan

Science.gov (United States)

Li, Qingbo; Wang, Xianyu; Song, Jing; Sui, Hongqi; Huang, Lei; Li, Lu

2012-12-01

Successive 52-week air monitoring of α-endosulfan (α-E), β-endosulfan (β-E) and endosulfan sulfate (E.S) in the gaseous and particulate phases was conducted in Dalian city, northeast China by using an active high-volume sampler. Significant seasonal and diurnal variations in endosulfan concentrations were observed. It was found that the concentration of gaseous-phase α-E peaked in the summer and the concentration of particulate phase α-E peaked in the winter. For E.S, both gaseous and particulate phase concentrations peaked in the summer. α-E was distributed predominantly in the gas phase in the summer but was distributed mainly in the particulate phase in the winter. β-E was distributed mainly in the gas phase in the summer and in the particulate phase at other times of the year. E.S was distributed mainly in the particulate phase throughout the year. Elevated temperatures facilitated the volatilization of α-E from particle surfaces but exerted little effect on β-E and had almost no effect on E.S. Trajectory-based analysis indicates that the seasonal variation in atmospheric concentrations of endosulfan in Dalian city was influenced strongly by the land and sea air masses. In addition, differences in endosulfan concentrations in the particulate phase between day and night were likely due to the circulation of sea/land breezes. The 'cold-condensation' effect occurring during the night may result in the attachment of endosulfan to the particulate phase.

Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

International Nuclear Information System (INIS)

Becker, D.L.; Lindquist, M.R.

1993-01-01

The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF 6 ). Uranium hexafluoride enriched greater than 1.0 wt percent 235 U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 and 178, or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF 6 cylinders/overpacks. International shipments typically are not made using dedicated trailers, and numerous trailers have been received at PORTS with improperly and potentially dangerously secured overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF 6 packaging tiedown and shipping practices used by PORTS; and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations

A numerical study on the characteristics of gaseous pollutant absorbed by a moving liquid aerosol

International Nuclear Information System (INIS)

Deng, J.J.; Du, Y.G.; Yu, Y.; Ding, J.

2008-01-01

Atmospheric pollution involving aerosols is becoming increasingly problematic. Since aerosols are small in size and have large specific surface areas, they can enhance some chemical reactions. Liquid aerosols in the air can absorb gaseous pollutants to adversely affect air quality and human health. This paper studied the characteristics of liquid aerosols and the absorption process of gaseous pollutants. Specifically, the paper presented a model to depict the characteristic of the absorption process of gaseous pollutant by a liquid aerosol with internal circulation and chemical reaction. The model assumed that liquid aerosols retain a spherical shape while moving freely in air. The finite volume method was used to develop an algorithm used to numerically simulate the experimental work of Walcek. The paper also discussed the numerical evaluation of the transient momentum and mass transfer characteristics of sulphur dioxide into a droplet. It was concluded that the chemical reaction increased the rate of mass transfer and the quasi-saturation time of aerosols, which provided a theoretical basis for the heterogeneous reaction of liquid aerosols. 3 refs., 6 figs

Dynamic Oxidation of Gaseous Mercury in the Arctic Troposphere at Polar Sunrise

DEFF Research Database (Denmark)

Lindberg, S. E.; Brooks, S.; Lin, C.-J.

2002-01-01

Gaseous elemental mercury (Hg0) is a globally distributed air toxin with a long atmospheric residence time. Any process that reduces its atmospheric lifetime increases its potential accumulation in the biosphere. Our data from Barrow, AK, at 71 degrees N show that rapid, photochemically driven...... oxidation of boundary-layer Hg0 after polar sunrise, probably by reactive halogens, creates a rapidly depositing species of oxidized gaseous mercury in the remote Arctic troposphere at concentrations in excess of 900 pg m(-3). This mercury accumulates in the snowpack during polar spring at an accelerated...... rate in a form that is bioavailable to bacteria and is released with snowmelt during the summer emergence of the Arctic ecosystem. Evidence suggests that this is a recent phenomenon that may be occurring throughout the earth's polar regions. Udgivelsesdato: 2002-Mar-15...