Science.gov

Sample records for accidental gas releases

  1. Estimation of vulnerable zones due to accidental release of toxic materials resulting in dense gas clouds.

    PubMed

    Singh, M P; Mohan, M; Panwar, T S; Chopra, H V

    1991-09-01

    Heavy gas dispersion models have been developed at IIT (hereinafter referred as IIT heavy gas models I and II) with a view to estimate vulnerable zones due to accidental (both instantaneous and continuous, respectively) release of dense toxic material in the atmosphere. The results obtained from IIT heavy gas models have been compared with those obtained from the DEGADIS model [Dense Gas Dispersion Model, developed by Havens and Spicer (1985) for the U.S. Coast Guard] as well as with the observed data collected during the Burro Series, Maplin Sands, and Thorney Island field trials. Both of these models include relevant features of dense gas dispersion, viz., gravity slumping, air entrainment, cloud heating, and transition to the passive phase, etc. The DEGADIS model has been considered for comparing the performance of IIT heavy gas models in this study because it incorporates most of the physical processes of dense gas dispersion in an elaborate manner, and has also been satisfactorily tested against field observations. The predictions from IIT heavy gas models indicate a fairly similar trend to the observed values from Thorney Island, Burro Series, and Maplin experiments with a tendency toward overprediction. There is a good agreement between the prediction of IIT Heavy Gas models I and II with those from DEGADIS, except for the simulations of IIT heavy gas model-I pertaining to very large release quantities under highly stable atmospheric conditions. In summary, the performance of IIT heavy gas models have been found to be reasonably good both with respect to the limited field data available and various simulations (selected on the basis of relevant storages in the industries and prevalent meteorological conditions performed with DEGADIS). However, there is a scope of improvement in the IIT heavy gas models (viz., better formulation for entrainment, modification of coefficients, transition criteria, etc.). Further, isotons (nomograms) have been prepared by using

  2. New tracers identify hydraulic fracturing fluids and accidental releases from oil and gas operations.

    PubMed

    Warner, N R; Darrah, T H; Jackson, R B; Millot, R; Kloppmann, W; Vengosh, A

    2014-11-01

    Identifying the geochemical fingerprints of fluids that return to the surface after high volume hydraulic fracturing of unconventional oil and gas reservoirs has important applications for assessing hydrocarbon resource recovery, environmental impacts, and wastewater treatment and disposal. Here, we report for the first time, novel diagnostic elemental and isotopic signatures (B/Cl, Li/Cl, δ11B, and δ7Li) useful for characterizing hydraulic fracturing flowback fluids (HFFF) and distinguishing sources of HFFF in the environment. Data from 39 HFFFs and produced water samples show that B/Cl (>0.001), Li/Cl (>0.002), δ11B (25-31‰) and δ7Li (6-10‰) compositions of HFFF from the Marcellus and Fayetteville black shale formations were distinct in most cases from produced waters sampled from conventional oil and gas wells. We posit that boron isotope geochemistry can be used to quantify small fractions (∼0.1%) of HFFF in contaminated fresh water and likely be applied universally to trace HFFF in other basins. The novel environmental application of this diagnostic isotopic tool is validated by examining the composition of effluent discharge from an oil and gas brine treatment facility in Pennsylvania and an accidental spill site in West Virginia. We hypothesize that the boron and lithium are mobilized from exchangeable sites on clay minerals in the shale formations during the hydraulic fracturing process, resulting in the relative enrichment of boron and lithium in HFFF. PMID:25327769

  3. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 5. Accidental Releases

    SciTech Connect

    Peterson, S

    2007-08-15

    Over the course of fifty-three years, LLNL had six acute releases of tritiated hydrogen gas (HT) and one acute release of tritiated water vapor (HTO) that were too large relative to the annual releases to be included as part of the annual releases from normal operations detailed in Parts 3 and 4 of the Tritium Dose Reconstruction (TDR). Sandia National Laboratories/California (SNL/CA) had one such release of HT and one of HTO. Doses to the maximally exposed individual (MEI) for these accidents have been modeled using an equation derived from the time-dependent tritium model, UFOTRI, and parameter values based on expert judgment. All of these acute releases are described in this report. Doses that could not have been exceeded from the large HT releases of 1965 and 1970 were calculated to be 43 {micro}Sv (4.3 mrem) and 120 {micro}Sv (12 mrem) to an adult, respectively. Two published sets of dose predictions for the accidental HT release in 1970 are compared with the dose predictions of this TDR. The highest predicted dose was for an acute release of HTO in 1954. For this release, the dose that could not have been exceeded was estimated to have been 2 mSv (200 mrem), although, because of the high uncertainty about the predictions, the likely dose may have been as low as 360 {micro}Sv (36 mrem) or less. The estimated maximum exposures from the accidental releases were such that no adverse health effects would be expected. Appendix A lists all accidents and large routine puff releases that have occurred at LLNL and SNL/CA between 1953 and 2005. Appendix B describes the processes unique to tritium that must be modeled after an acute release, some of the time-dependent tritium models being used today, and the results of tests of these models.

  4. European research in accidental release phenomena

    SciTech Connect

    Wicks, P.J.; Cole, S.T.

    1995-12-31

    The European Commission (CEC) has an ongoing research program in the field of the environment. Part of this work concerns the consequences of accidental releases from industrial plants, and covers hazards posing an off-site threat. This paper reviews some of the main results arising from this work. In addition to consequence modeling, the research has also included work on risk assessment and management. After a brief introduction to CEC research, the work is presented in five sections corresponding the main areas of work: flashing flow, atmospheric dispersion, jet-flame attack on vessels, gas explosions and storage fires.

  5. Computer code to assess accidental pollutant releases

    SciTech Connect

    Pendergast, M.M.; Huang, J.C.

    1980-07-01

    A computer code was developed to calculate the cumulative frequency distributions of relative concentrations of an air pollutant following an accidental release from a stack or from a building penetration such as a vent. The calculations of relative concentration are based on the Gaussian plume equations. The meteorological data used for the calculation are in the form of joint frequency distributions of wind and atmospheric stability.

  6. Approaches for preventing and mitigating accidental gaseous chemical releases

    SciTech Connect

    Fthenakis, V.M.

    1996-12-31

    This paper presents a review of approaches to prevent and mitigate accidental releases of toxic and flammable gases. The prevention options are related to: choosing safer processes and materials, preventing initiating events, preventing or minimizing releases, and preventing human exposures. the mitigation options include: secondary confinement, de-inventory, vapor barriers, and water sprays/monitors. Guidelines for the design and operation of effective post-release mitigation systems are also presented.

  7. An evaluation of available models for assessing accidental releases of extremely hazardous substances

    SciTech Connect

    Yuhas, J.A.; Taylor, R.K.; Dutcher, D.D.

    1996-12-31

    Section 112(r) of the Clean Air Act calls for the promulgation of new rules to prevent and minimize the consequences of accidental releases of chemicals. The rules will require the development of Risk Management Plans (RMP`s) and ambient air consequence analyses of potential releases. A series of dense gas dispersion, puff release, and accidental release models are being introduced to meet the demands of the new regulatory requirements for various release scenarios. Studies to data have shown that no single model out performs all others when tested against field experiment data. Also, little has been done to assess the applicability of these models to actual modeling scenarios and to the Section 112(r) modeling requirements. This paper assesses the applicability of current guideline models to the Section 112(r) requirements and points out areas where the guideline models cannot meet these requirements. Additional models are presented as potential solutions to this problem.

  8. Modeling downwind hazards after an accidental release of chlorine trifluoride

    SciTech Connect

    Lombardi, D.A.; Cheng, Meng-Dawn

    1996-05-01

    A module simulating ClF{sub 3} chemical reactions with water vapor and thermodynamic processes in the atmosphere after an accidental release has been developed. This module was liked to the HGSYSTEM. Initial model runs simulate the rapid formation of HF and ClO{sub 2} after an atmospheric release of ClF{sub 3}. At distances beyond the first several meters from the release point, HF and ClO{sub 2} concentrations pose a greater threat to human health than do ClF{sub 3} concentrations. For most of the simulations, ClF{sub 3} concentrations rapidly fall below the IDLH. Fro releases occurring in ambient conditions with low relative humidity and/or ambient temperature, ClF{sub 3} concentrations exceed the IDLH up to almost 500 m. The performance of this model needs to be determined for potential release scenarios that will be considered. These release scenarios are currently being developed.

  9. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 9. CONTROL OF ACCIDENTAL RELEASES OF CHLORINE

    EPA Science Inventory

    The manual discusses reducing the risk associated with an accidental release of chlorine. It identifies examples of potential causes of accidental releases that apply to processes that use chlorine, as well as measures that may be taken to reduce the accidental release risk. Such...

  10. 40 CFR 63.95 - Additional approval criteria for accidental release prevention programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accidental release prevention programs. 63.95 Section 63.95 Protection of Environment ENVIRONMENTAL... Additional approval criteria for accidental release prevention programs. (a) A State submission for approval... (“federally-listed chemicals”) that an approvable State Accidental Release Prevention program is...

  11. Method and apparatus for controlling accidental releases of tritium

    DOEpatents

    Galloway, Terry R. [Berkeley, CA

    1980-04-01

    An improvement in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release.

  12. Method and apparatus for controlling accidental releases of tritium

    DOEpatents

    Galloway, T.R.

    1980-04-01

    An improvement is described in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release. 1 fig.

  13. Numerical simulation of industrial and accidental release formation and transport

    SciTech Connect

    Piskunov, V.N.; Aloyan, A.A.; Gerasimov, V.M.; Pinaev, V.S.; Golubev, A.I.; Yanilkin, Yu.V.; Ivanov, N.V.; Nikonov, S.N.; Kharchenko, A.I.

    1995-05-01

    Statement of work for contract 006 {open_quotes}Mathematical simulation of industrial and accidental release formation and transport{close_quotes} implies that the final result of the activity within this task will be VNIIEF developed techniques which will provide for the prediction of the post-accidental environment. Report [1] presents the description of physical models and calculation techniques which were chosen by VNIIEF to accomplish this task. These techniques were analysed for their capabilities, the areas of their application were defined, modifications within contract 006 were described, the results of test and methodical calculations were presented. Moreover, the experimental data were analysed over the source parameters and contamination measurements which can be used in the comparison with the calculation results. Based an these data this report compares the calculation results obtained with VNIIEF calculation techniques with the LANL-presented experimental results. The calculations which statements and results are given in section 1, included the following processes: explosion cloud ascent dynamics and jet release origin; aerosols kinetics in the release source including composite particle origin in the explosion cloud caused by radioactive substance sorption an the soil particles; contaminant transport in atmosphere and their in-site fallout due to the accidental explosions and fires; atmospheric flow dynamics and industrial contamination transfer over the complicated terrain. The calculated results were compared with the experimental data. Section 2 presents the parameters for a typical source in the explosion accidents based an the experimental results and calculated data from Section 1, as well as contamination patterns were calculated with basic technique {open_quotes}Prognosis{close_quotes}.

  14. Software for emission rate modeling of accidental toxic releases

    SciTech Connect

    Kumar, A.; Vashisth, S.

    1999-08-01

    This book fulfills the need for Section 112(r) of the Clean Air Act Amendments of 1990. This software is based on the guidelines released by the USEPA. It includes manual and proprietary software on CDROM. Contents include release scenario description (two-phase and single-phase choked/unchoked gas release, two-phase pressurized and refrigerated liquid release, single-phase high and low volatility liquid release); emission rate model development for each release class; software design and software evaluation and application.

  15. Control of accidental releases of hydrogen selenide in vented storage cabinets

    NASA Astrophysics Data System (ADS)

    Fthenakis, V. M.; Moskowitz, P. D.; Sproull, R. D.

    1988-07-01

    Highly toxic hydrogen selenide and hydrogen sulfide gases are used in the production of copper-indium-diselenide photovoltaic cells by reactive sputtering. In the event of an accident, these gases may be released to the atmosphere and pose hazards to public and occupational safety and health. This paper outlines an approach for designing systems for the control of these releases given the uncertainty in release conditions and lack of data on the chemical systems involved. Accidental releases of these gases in storage cabinets can be controlled by either a venturi and packed-bed scrubber and carbon adsorption bed, or containment scrubbing equipment followed by carbon adsorption. These systems can effectively reduce toxic gas emissions to levels needed to protect public health. The costs of these controls (˜0.012/Wp) are samll in comparison with current (˜6/Wp) and projected (˜I/Wp) production costs.

  16. PREVENTION REFERENCE MANUAL: CONTROL TECHNOLOGIES, VOLUME 2: POST-RELEASE MITIGATION MEASURES FOR CONTROLLING ACCIDENTAL RELEASES OF AIR TOXICS

    EPA Science Inventory

    The volume discusses prevention and protection measures for controlling accidental releases of air toxics. The probability of accidental releases depends on the extent to which deviations (in magnitude and duration) in the process can be tolerated before a loss of chemical contai...

  17. PREVENTION REFERENCE MANUAL: CONTROL TECHNOLOGIES, VOL. 2. POST-RELEASE MITIGATION MEASURES FOR CONTROLLING ACCIDENTAL RELEASES OF AIR TOXICS

    EPA Science Inventory

    The volume discusses prevention and protection measures for controlling accidental releases of air toxics. The probability of accidental releases depends on the extent to which deviations (in magnitude and duration) in the process can be tolerated before a loss of chemical contai...

  18. Acute health effects of accidental chlorine gas exposure

    PubMed Central

    2014-01-01

    Objectives This study was conducted to report the course of an accidental release of chlorine gas that occurred in a factory in Gumi-si, South Korea, on March 5, 2013. We describe the analysis results of 2 patients hospitalized because of chlorine-induced acute health problems, as well as the clinical features of 209 non-hospitalized patients. Methods We analyzed the medical records of the 2 hospitalized patients admitted to the hospital, as well as the medical records and self-report questionnaires of 209 non-hospitalized patients completed during outpatient treatment. Results Immediately after the exposure, the 2 hospitalized patients developed acute asthma-like symptoms such as cough and dyspnea, and showed restrictive and combined pattern ventilatory defects on the pulmonary function test. The case 1 showed asthma-like symptoms over six months and diurnal variability in peak expiratory flow rate was 56.7%. In case 2, his FEV1 after treatment (93%) increased by 25% compared to initial FEV1 (68%). Both cases were diagnosed as chlorine-induced reactive airways dysfunction syndrome (RADS) on the basis of these clinical features. The most frequent chief complaints of the 209 non-hospitalized patients were headache (22.7%), followed by eye irritation (18.2%), nausea (11.2%), and sore throat (10.8%), with asymptomatic patients accounting for 36.5%. The multiple-response analysis of individual symptom revealed headache (42.4%) to be the most frequent symptom, followed by eye irritation (30.5%), sore throat (30.0%), cough (29.6%), nausea (27.6%), and dizziness (27.3%). Conclusions The 2 patients hospitalized after exposure to chlorine gas at the leakage site showed a clinical course corresponding to RADS. All of the 209 non-hospitalized patients only complained of symptoms of the upper airways and mucous membrane irritation. PMID:25852940

  19. Prevention reference manual: chemical specific. Volume 9. Control of accidental releases of chlorine

    SciTech Connect

    Davis, D.S.; DeWolf, G.B.; Quass, J.D.; Wert, K.P.

    1987-08-01

    The manual discusses reducing the risk associated with an accidental release of chlorine. It identifies examples of potential causes of accidental releases that apply to processes that use chlorine, as well as measures that may be taken to reduce the accidental release risk. Such measures include recommendations on plant design practices; prevention, protection, and mitigation technologies; and operation and maintenance practices. It provides conceptual cost estimates of possible prevention, protection, and mitigation measures. Chlorine has an IDLH (immediately dangerous to life and health) concentration, making it a substantial acute toxic hazard.

  20. Accidental release of toxic chemicals: influence of the main input parameters on consequence calculation.

    PubMed

    Bubbico, Roberto; Mazzarotta, Barbara

    2008-03-01

    In the present paper the accidental release of toxic chemicals has been taken into consideration, and a sensitivity analysis study of the corresponding consequences calculation has been carried out. Four different toxic chemicals have been chosen for the simulations, and the effect of the variability of the main input parameters on the extension of the impact areas has been assessed. The results show that the influence of these parameters depends on the physical properties of the released substance and that not always the widely known rules of thumb, such as the positive influence of the wind velocity on gas dispersion, apply. In particular, the boiling temperature of the chemical has revealed to be the main parameter affecting the type of dependence of the impact distances on the input variables. PMID:17630190

  1. Accidental release of fluoride into experimental pond and accumulation in sediments, plants, algae, molluscs and fish.

    PubMed

    Kudo, A; Garrec, J P

    1983-09-01

    The fate of fluoride in a simulated accidental release into an experimental pond was observed for 30 days in Grenoble, France. The components investigated were water, sediments, plants, algae, molluscs, and fish. Twenty-four hours after the release, most (99.8%) of the fluoride was distributed in the physical components (water and sediments), and the biological agents contained only 0.2% of the fluoride released. Despite an exposure to hot spots of 5000 ppm at the beginning of the accidental release, no visible toxic effects were observed on the biological components such as plants, algae, molluscs, and fish. The effects of the physical components in the defluoridation showed a significant role in the control the accidental release of fluoride in the aquatic system. PMID:6635267

  2. Accidental release of fluoride into experimental pond and accumulation in sediments, plants, algae, molluscs, and fish

    SciTech Connect

    Kudo, A.; Garrec, J.P.

    1983-09-01

    The fate of fluoride in a simulated accidental release into an experimental pond was observed for 30 days in Grenoble, France. The components investigated were water, sediments, plants, algae, molluscs, and fish. Twenty-four hours after the release, most (99.8%) of the fluoride was distributed in the physical components (water and sediments), and the biological agents contained only 0.2% of the fluoride released. Despite an exposure to hot spots of 5000 ppm at the beginning of the accidental release, no visible toxic effects were observed on the biological components such as plants, algae, molluscs, and fish. The effects of the physical components in the defluoridation showed a significant role in the control the accidental release of fluoride in the aquatic system.

  3. Dispersion modeling of accidental releases of toxic gases - Sensitivity study and optimization of the meteorological input

    NASA Astrophysics Data System (ADS)

    Baumann-Stanzer, K.; Stenzel, S.

    2009-04-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. Uncertainties in the meteorological input together with incorrect estimates of the source play a critical role for the model results. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program at the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. This presentation gives a short introduction to the project and presents the results of task 1 (meteorological input). The results of task 2 are presented by Stenzel and Baumann-Stanzer in this session. For the aim of this project, the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) was used. INCA (Integrated Nowcasting through Comprehensive Analysis) data were calculated with 1 km horizontal resolution and

  4. Atmospheric dispersion of ammonia accidentally released from the 242-A Evaporator, Hanford Site, Richland, Washington

    SciTech Connect

    Daling, P.M.; Lavender, J.C.

    1997-11-01

    Two errors have been identified in the authorization basis for the 242-A Evaporator at the Hanford Site. These errors, which appear in the 242-A Evaporator/Crystallizer Final Safety Analysis Report analysis of ammonia gas concentrations accidentally released from the 242-A Evaporator, are: (1) the vessel ventilation system flow rate used in the previous calculations is a factor of ten higher than the actual flow rate, and (2) the previous calculations did not account for the ammonia source term reduction that would occur via condensation of ammonia vapors, which will remove a large fraction of the ammonia from the exhaust gas stream. The purpose of this document is to correct these errors and recalculate the maximum ground-level concentrations of ammonia released to the environment as a result of potential errors in blending Evaporator feed. The errors offset each other somewhat, so it is unlikely that the 242-A Evaporator has operated outside its current authorization basis. However, the errors must be corrected and the results incorporated into a revision of the 242-A Evaporator/Crystallizer Safety Analysis Report, WHC-SD-WM-SAR-023. An EPA-approved atmospheric dispersion model, SCREEN3, was used to recalculate the maximum ground-level concentrations of ammonia that would be released from the 242-A Evaporator as a result of a feed-blending error. The results of the re-analysis of the 242-A Evaporator`s ammonia release scenario are as follows. The onsite receptor 100 m away from the release point (242-A vessel vent stack) is projected to be exposed to a maximum ground-level concentration of ammonia of 8.3 ppm. The maximally-exposed offsite receptor, located at the nearest Hanford Site boundary 16 km away from the 242-A vessel vent stack, will be exposed to a maximum ground-level concentration of 0.11 ppm ammonia.

  5. Modeling accidental releases to the atmosphere of a dense reactive chemical (Uranium hexafluoride)

    NASA Astrophysics Data System (ADS)

    Hanna, Steven R.; Chang, Joseph C.; Zhang, Xiaoming J.

    In order to model the atmospheric transport and dispersion of dense reactive chemicals such as uranium hexafluoride (UF 6), it is necessary to include algorithms that account for heat exchanges due to chemical reactions and phase changes. UF 6 may be released accidentally at uranium-enrichment plants as a warm gas from a pipeline rupture, or as a flashing liquid from a pressurized tank or line break. The resulting plume is initially very dense due to the large molecular weight of UF 6, but may become lighter-than-air as the UF 6 reacts with water vapor to form HF, which has a molecular weight less than that of air, and which may cause an increase in plume temperature due to the exothermic reaction. The major chemical and thermodynamic processes related to UF 6 have been incorporated in a modified version of an existing dense gas model, HGSYSTEM. The same general approach could be used to include other reactive chemicals in the modeling system. New modules that are applicable to any type of chemical release have also been added to HGSYSTEM to account for building downwash, lift-off of warm plumes from the ground, and deposition. The revised HGSYSTEM/UF 6 model has been evaluated with field data from UF 6 tests. The sensitivities of the model predictions to variations in input parameters have been assessed.

  6. Along-wind dispersion of short-duration accidental releases of hazardous gases

    SciTech Connect

    Hanna, S.R.

    1996-12-31

    Most accidental releases of hazardous gases are of short duration (a few minutes, at most) because of limitations to the total mass available for release or because of mitigation measures such as automatic valve closure or water spray curtains. The resulting cloud would then have the shape of an elongated puff at distances of about 500 m to 1,000 m when it encounters nearby population centers. The maximum concentration in the elongated puff depends strongly on whether the along-wind dispersion coefficient, {sigma}{sub x}, is larger than the length of the finite duration core of the cloud, u{sub c}T{sub d}, where T{sub d} is the source release duration and u{sub c} is the advective speed of the cloud. The along-wind dispersion coefficient, {sigma}{sub x}, is determined by the turbulent energy and the wind-shear over the cloud depth. Both the wind-shear and the advective speed of the cloud, u{sub c}, are functions of time or distance, since they represent concentration-weighted averages over the depth of the cloud, which is steadily increasing. Boundary-layer similarity theories are used to develop simplified formulas for {sigma}{sub x}, which are tested using data from laboratory and field experiments. The theory is expanded to include dense gas clouds and the resulting associated enhanced along-wind dispersion due to gravity slumping.

  7. Clean Air Act Title III accidental emission release risk management program, and how it applies to landfills

    SciTech Connect

    Hibbard, C.S.

    1999-07-01

    On June 20, 1996, EPA promulgated regulations pursuant to Title III of the Clean Air Act (CAA) Amendments of 1990 (Section 112(r)(7) of the CAA). The rule, contained in 40 CFR Part 68, is called Accidental Release Prevention Requirements: Risk Management Programs, and is intended to improve accident prevention and emergency response practices at facilities that store and/or use hazardous substances. Methane is a designated highly hazardous chemical (HHC) under the rule. The rule applies to facilities that have 10,000 pounds of methane or more in any process, roughly equivalent to about 244,000 cubic feet of methane. The US EPA has interpreted this threshold quantity as applying to landfill gas within landfills. This paper presents an overview of the Accidental Release Prevention regulations, and how landfills are affected by the requirements. This paper describes methodologies for calculating the threshold quantity of landfill gas in a landfill. Methane is in landfill gas as a mixture. Because landfill gas can burn readily, down to concentrations of about five percent methane, the entire landfill gas mixture must be treated as the regulated substance, and counts toward the 10,000-pound threshold. It is reasonable to assume that the entire landfill gas collection system, active or passive, is filled with landfill gas, and that a calculation of the volume of the system would be a calculation of the landfill gas present in the process on the site. However, the US EPA has indicated that there are some instances in which pore space gas should be included in this calculation. This paper presents methods available to calculate the amount of pore space gas in a landfill, and how to determine how much of that gas might be available for an explosion. The paper goes through how to conduct the release assessment to determine the worst-case hazard zone around the landfill.

  8. Atmospheric Dispersion Code System for Evaluating Accidental Radioactivity Releases from Nuclear Power Stations.

    1983-06-28

    Version: 00 PAVAN estimates down-wind ground-level air concentrations for potential accidental releases of radioactive material from nuclear facilities. Options can account for variation in the location of release points, additional plume dispersion due to building wakes, plume meander under low wind speed conditions, and adjustments to consider non-straight trajectories. It computes an effective plume height using the physical release height which can be reduced by inputted terrain features.

  9. Mitigation options for accidental releases of hazardous gases

    SciTech Connect

    Fthenakis, V.M.

    1995-05-01

    The objective of this paper is to review and compare technologies available for mitigation of unconfined releases of toxic and flammable gases. These technologies include: secondary confinement, deinventory, vapor barriers, foam spraying, and water sprays/monitors. Guidelines for the design and/or operation of effective post-release mitigation systems and case studies involving actual industrial mitigation systems are also presented.

  10. Modelling dispersion processes of hypothetical nuclear accidental release on different scales

    NASA Astrophysics Data System (ADS)

    Mészáros, R.; Lagzi, I.; Molnár, F., Jr.; Vincze, Cs.; Leelőssy, Á.; Kovács, T.

    2010-09-01

    An increased attention of anthropogenic effects on the environment was observable in the last decades. As more nuclear, biological and industrial accidents occurred in the different part of the world, there is an increased demand both on the part of population and scientific society for the understanding and effective prediction of the environmental, social or economical effects of continuous or a possible accidental release. On the basis of sophisticated dispersion model calculations, the decision makers could make important arrangements, which can save human lives. For this purpose, accidental release models for different spatial and time scales were developed. Model estimations of radionuclide dispersions from the Paks Nuclear Power Plant (Hungary) were also carried out from regional to local scales. With the TREX-Euler, multi-layered, Eulerian passive tracer dispersion model, the transport and deposition of air pollutants over the Central European region were simulated under different weather conditions. For mesoscale simulation of accidental release, the stochastic TREX-Lagrangian particle model was chosen and developed. Both hypothetical accidental releases and continuous environmental loads were simulated. Additionally, near the point source, CFD simulations with A2C model were evaluated. Model estimations on different scales and their sensitivity analyses are presented in this study.

  11. SUMMARY OF ACCIDENTAL RELEASES OF RADIOACTIVITY DETECTED OFF THE NEVADA TEST SITE, 1963-1986

    EPA Science Inventory

    Of the more than 450 underground nuclear explosives tests conducted at the Nevada Test Site from August 1963 (signing of the Limited Test Ban Treaty) through the end of 1986, only 23 accidentally released radioactivity that was detectable beyond the boundary of the NTS. Of these ...

  12. 78 FR 79317 - Approval of Request for Delegation of Authority for Prevention of Accidental Release, North...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-30

    ... mean Code of Federal Regulations (vi) The initials FR mean Federal Register (vii) The initials NDCC... (61 FR 31668, June 20, 1996). These regulations require owners and operators of stationary sources... Accidental Release, Clean Air Act Section 112(r) Program'' EPA-R08-OAR-2013-0330, 78 FR 66321 (Nov. 5,...

  13. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOL. 15: CONTROL OF ACCIDENTAL RELEASES OF SULFUR TRIOXIDE

    EPA Science Inventory

    The report, discussing sulfur trioxide (SO3), is one of a series addressing the prevention of accidental releases of toxic chemicals. SO3, a clear oily liquid or solid at typical ambient conditions, has an Immediately Dangerous to Life and Health (IDLH) concentration of 20 ppm, w...

  14. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC, VOLUME 13: CONTROL OF ACCIDENTAL RELEASES OF METHYL ISOCYANATE

    EPA Science Inventory

    This is one of a series of manuals addressing accidental releases of toxic chemicals. Methyl isocyanite (MIC) has an Immediately Dangerous to Life and Health (IDLH) concentration of 20 ppm, making it a substantially acute toxic hazard. Reducing the risk associated with an acciden...

  15. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC, VOLUME 14: CONTROL OF ACCIDENTAL RELEASES OF PHOSGENE

    EPA Science Inventory

    The report, discussing phosgene, is one of a series addressing the prevention of accidental releases of toxic chemicals. Phosgene, a highly reactive and corrosive liquid that boils at room temperature has an Immediately Dangerous to Life and Health (lDLH) conctntration of 2 ppm, ...

  16. PROBABILITY AND CONTROL COST EFFECTIVENESS FOR ACCIDENTAL TOXIC CHEMICAL RELEASES

    EPA Science Inventory

    The paper shows how fault tree analysis (FTA) of a process system can be used to compare the relative effectiveness of various equipment, design, and operating measures for release prevention and protection applied to process streams. It also shows how the costs of various safety...

  17. Dispersion modeling of accidental releases of toxic gases - utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-09-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios”), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Viennese fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program of the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. For the purpose of our study the following models were tested and compared: ALOHA (Areal Location of Hazardous atmosphere, EPA), MEMPLEX (Keudel av-Technik GmbH), Trace (Safer System), Breeze (Trinity Consulting), SAM (Engineering office Lohmeyer). A set of reference scenarios for Chlorine, Ammoniac, Butane and Petrol were proceed, with the models above, in order to predict and estimate the human exposure during the event. Furthermore, the application of the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) in case of toxic release was

  18. PREVENTION REFERENCE MANUAL: CONTROL TECHNOLOGIES. VOLUME 1. PREVENTION AND PROTECTION TECHNOLOGIES FOR CONTROLLING ACCIDENTAL RELEASES OF AIR TOXICS

    EPA Science Inventory

    The volume discusses prevention and protection measures for controlling accidental releases of air toxics. The probability of accidental releases depends on the extent to which deviations (in magnitude and duration) in the process can be tolerated before a loss of chemical contai...

  19. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 2. CONTROL OF ACCIDENTAL RELEASES OF CHLORINE (SCAQMD) (SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT)

    EPA Science Inventory

    The manual discusses reducing the risk associated with an accidental release of chlorine. It identifies some of the potential causes of accidental releases that apply to the processes that use chlorine. It also identifies examples of potential causes, as well as measures that may...

  20. Effectiveness of common shelter-in-place techniques in reducing ammonia exposure following accidental release.

    PubMed

    Tarkington, Brett; Harris, Angela J; Barton, Paul S; Chandler, Ben; Goad, Phillip T

    2009-04-01

    Shelter-in-place strategies such as remaining indoors; breathing through a damp cloth; sealing cracks in windows and doors using towels, duct tape, or plastic sheeting; and running a shower are often recommended by emergency response officials to protect against accidental or intentional release of hazardous airborne chemicals and biologicals. Similar recommendations have been made to and used by community members exposed to anhydrous ammonia after catastrophic release of ammonia gas due to a derailment or other accidents. Such incidents have resulted in fatalities and serious injury to exposed individuals; however, other individuals within the same area have escaped injury and, in many cases, sustained no injuries as a result of sheltering-in-place. Although there are some studies that have evaluated the effectiveness of remaining in the home or breathing through a damp cloth to reduce exposure to various agents, there have been no studies that directly address the efficacy of running the shower in reducing exposure to ammonia gas. The present study was designed to simulate sheltering-in-place inside a typical bathroom with the shower running. The effectiveness of breathing through a damp cloth was also evaluated using a CPR mannequin placed inside a chamber built to represent a typical household bathroom. Ammonia gas at 300 or 1000 ppm was added to the chamber until the concentration peaked and stabilized, then the shower was turned on and the ammonia gas concentration was continuously monitored. In the mannequin studies, using a damp cloth reduced exposure to ammonia gas by 2- to 18-fold. Turning on the shower was even more effective at reducing ammonia levels. After 27 min, the ammonia concentration in the chamber was reduced to 2% of the initial concentration, even though gas was being continuously added to the chamber. These results indicate that use of shelter-in-place strategies substantially reduces ammonia exposure and that by combining shelter

  1. Gas releases from salt

    SciTech Connect

    Ehgartner, B.; Neal, J.; Hinkebein, T.

    1998-06-01

    The occurrence of gas in salt mines and caverns has presented some serious problems to facility operators. Salt mines have long experienced sudden, usually unexpected expulsions of gas and salt from a production face, commonly known as outbursts. Outbursts can release over one million cubic feet of methane and fractured salt, and are responsible for the lives of numerous miners and explosions. Equipment, production time, and even entire mines have been lost due to outbursts. An outburst creates a cornucopian shaped hole that can reach heights of several hundred feet. The potential occurrence of outbursts must be factored into mine design and mining methods. In caverns, the occurrence of outbursts and steady infiltration of gas into stored product can effect the quality of the product, particularly over the long-term, and in some cases renders the product unusable as is or difficult to transport. Gas has also been known to collect in the roof traps of caverns resulting in safety and operational concerns. The intent of this paper is to summarize the existing knowledge on gas releases from salt. The compiled information can provide a better understanding of the phenomena and gain insight into the causative mechanisms that, once established, can help mitigate the variety of problems associated with gas releases from salt. Outbursts, as documented in mines, are discussed first. This is followed by a discussion of the relatively slow gas infiltration into stored crude oil, as observed and modeled in the caverns of the US Strategic Petroleum Reserve. A model that predicts outburst pressure kicks in caverns is also discussed.

  2. Modelling of accidental released toxic gases for emergency responders in Austria, Kosovo and Bulgaria.

    NASA Astrophysics Data System (ADS)

    Stenzel, Sirma; Baumann-Stanzer, Kathrin; Gashi, Salih; Thaci, Bashkim; Batchvarova, Ekaterina; Spassova, Tatiana

    2010-05-01

    In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. A number of models for the prediction and simulation of hazard areas affected by accidental releases of toxic gases are available worldwide. Modelling accidental releases may be required for a variety of reasons: for analyzing different accidental toxic release scenarios ("worst-case scenarios"), for preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management (e.g. in the frame of the SEVESO directive). Depending on the demand and the particular purposes, the choice of the appropriate model is up to the authorities. The one year project was funded by the Austrian Science and research liaison Office (ASO, www.aso.zsi.at) as a part of the program: Research Cooperation and Networking between Austria, the public higher education institutions in Kosovo and South Eastern Europe. The project was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG, http://www.zamg.ac.at) in cooperation with the University of Prishtina (Kosovo, www.uni-pr.edu and the National Institute of meteorology and Hydrology (NIHM Bulgaria, www.meteo.bg). One of the main purposes of the project was to provide the both partners with basic knowledge in modelling with accidental release of toxic gases, based on the practical experience of the meteorologists from the ZAMG in the area. This knowledge can be used as scientific response to society driven current or upcoming problems especially in Kosovo. The activities involved know-how transfer on European standards and practice among the project partners, as well as joint efforts to adapt and disseminate the scientific methods and results in Kosovo. Within the project, the partners from Kosovo and Bulgaria were introduced to the atmospheric dispersion model (ALOHA - Areal

  3. Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-04-01

    Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades. Sirma Stenzel, Kathrin Baumann-Stanzer In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. For hazard prediction and simulation of the hazard zones a number of air dispersion models are available. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for display the results, they are easy to use and can operate fast and effective during stress situations. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. There are also possibilities for model direct coupling to automatic meteorological stations, in order to avoid uncertainties in the model output due to insufficient or incorrect meteorological data. Another key problem in coping with accidental toxic release is the relative width spectrum of regulations and values, like IDLH, ERPG, AEGL, MAK etc. and the different criteria for their application. Since the particulate emergency responders and organizations require for their purposes unequal regulations and values, it is quite difficult to predict the individual hazard areas. There are a quite number of research studies and investigations coping with the problem, anyway the end decision is up to the authorities. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and

  4. Use of 3D numerical simulation model for impact analysis of accidental release of hazardous substance in urban environment

    SciTech Connect

    Kao, C.Y.J.; Ni-Bin Chang

    1996-12-31

    A three dimensional, time dependent, numerical model is developed for the simulation of vapor cloud of chemical substance being accidentally released in urban environment. Such a modeling technique as it would apply to chemical emergency response situation in the urban environment is considerably important due to the behavior of heavy gas diffusion and dispersion. Within the scope of this study, the distribution of chemicals being released is estimated based on the kernel density estimator along with a three-dimension wind field model in which the horizontal momentum equations, turbulence kinetic energy equation, and a set of conservation equations are integrated together. By utilizing the capability of numerical analysis, the solution of such a hydrodynamic model can be found to constitute the analytical framework in the process of pollutant transport and even transformation. Such a result is required for both short-term and long-term risk analyses in urban environment.

  5. Doses from accidental releases of tritium and activation products into the atmosphere

    NASA Astrophysics Data System (ADS)

    Raskob, W.

    1993-06-01

    In view of public acceptance and the licensing procedure of projected fusion reactors, the release of tritium and activation products during normal operation as well as after accidents is a significant safety aspect. Calculations have been performed under accidental conditions for unit releases of corrosion products from water coolant loops, of first wall erosion products including different coating materials, and of tritium in its chemical form of tritiated water (HTO). Dose assessments during normal operation have been performed for corrosion products from first wall primary coolant loop and for tritium in both chemical forms (HT/HTO). The two accident consequence assessment (ACA) codes UFOTRI and COSYMA have been applied for the deterministic dose calculations with nearly the same input variables and for several radiological source terms. Furthermore, COSYMA and NORMTRI have been applied for routine release scenarios. The paper analyzes the radioation doses to individuals and the population resulting from the different materials assumed to be released in the environment.

  6. Emergency operational meteorological considerations during an accidental release of hazardous chemicals. Technical memo

    SciTech Connect

    Mueller, P.; Galt, J.

    1991-08-01

    The accidental release of toxic chemicals into the atmosphere has always been of great concern among local emergency response authorities. Evacuation of persons in and around the affected area, the amount of chemical spilled, and atmospheric conditions governing the downwind concentrations are among some of the more pressing issues confronting local hazardous materials (HAZMAT) personnel. Recently, the National Oceanic and Atmospheric Administration (NOAA) has embarked upon a program to provide chemical dispersion models to local HAZMAT groups. Greater public awareness of the dangers of toxic chemicals will likely mandate greater involvement by a number of government agencies, including the National Weather Service (NWS). HAZMAT personnel have not yet fully utilized the services of NWS meteorologists. In the future, NWS meteorologists and meteorological technicians may be asked to provide weather data as well as initial and short range weather forecasts (including trajectory forecasts) to emergency response managers responsible for protecting people from accidental releases of toxic spills. While a wide number of dispersion models exist, many are very similar when it comes to the type of meteorological input required to run them. The paper focuses on the input so that meteorologists may be better informed when they are called upon to provide assistance during a hazardous chemical spill in their area.

  7. The potential for damage from the accidental release of conductive carbon fibers from aircraft composites

    NASA Technical Reports Server (NTRS)

    Bell, V. L.

    1980-01-01

    Carbon and graphite fibers are known to be electrically conductive. The rapidly accelerating use of carbon fibers as the reinforcement in filamentary composite materials brought up the possibility of accidental release of carbon fibers from the burning of crashed commercial airliners with carbon composite parts. Such release could conceivably cause widespread damage to electrical and electronic equipment. The experimental and analytical results of a comprehensive investigation of the various elements necessary to assess the extent of such potential damage in terms of annual expected costs and maximum losses at low probabilities of occurrence are presented. A review of NASA materials research program to provide alternate or modified composite materials to overcome any electrical hazards from the use of carbon composites in aircraft structures is described.

  8. Dynamic evaluation of environmental impact due to tritium accidental release from the fusion reactor.

    PubMed

    Nie, Baojie; Ni, Muyi; Jiang, Jieqiong; Wu, Yican

    2015-10-01

    As one of the key safety issues of fusion reactors, tritium environmental impact of fusion accidents has attracted great attention. In this work, the dynamic tritium concentrations in the air and human body were evaluated on the time scale based on accidental release scenarios under the extreme environmental conditions. The radiation dose through various exposure pathways was assessed to find out the potential relationships among them. Based on this work, the limits of HT and HTO release amount for arbitrary accidents were proposed for the fusion reactor according to dose limit of ITER. The dynamic results aim to give practical guidance for establishment of fusion emergency standard and design of fusion tritium system. PMID:26164282

  9. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Not Available

    1989-06-01

    Accidental releases of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher.

  10. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Not Available

    1989-06-01

    Accidental releases of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher. 8 refs., 69 figs., 50 tabs.

  11. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Not Available

    1989-06-01

    Accidental release of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher.

  12. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Not Available

    1989-06-01

    Accidental release of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous studies experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The large scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher.

  13. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Neff, D.E. . Fluid Mechanics and Wind Engineering Lab.)

    1989-06-01

    Accidental releases of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The large scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher.

  14. Simulation of accidental UF/sub 6/ releases in support of the safety analysis effort

    SciTech Connect

    Just, R.A.

    1986-01-01

    The safety analysis of the US uranium enrichment facilities requires that postulated accidental releases of UF/sub 6/ be simulated. In order to predict the human health consequences of a postulated UF/sub 6/ release, two types of information are needed: (1) predicted toxicant concentrations and exposure durations at pertinent locations (calculated by a dispersion model), and (2) toxicity data which support the assessment of the human health consequences of a known exposure to a mixture of UF/sub 6/ and UF/sub 6/ hydrolysis products. This report describes the development of a Gaussian dispersion model for simulating UF/sub 6/ dispersion and the plans for developing a puff dispersion model.

  15. Accidental explosions

    SciTech Connect

    Medard, L.A.

    1989-01-01

    This book presents a survey of accidental explosions, their nature and their causes. It covers the physical and chemical conditions governing accidental explosions, whether in the gas phase, or in the liquid or solid state. The theoretical background of the kinetics and thermochemistry of explosions is outlined, followed by a detailed study of the explosion and detonation properties of both gas and condensed explosives. The author surveys a wide variety of substances in daily use in industry which can give rise to accidental explosions. Their properties and hazards are spelt out in detail, the discussion drawing on a long history of sometimes catastrophic accidents. Includes case studies, tables of physical and chemical data.

  16. The accidental release of exotic species from breeding colonies and zoological collections.

    PubMed

    Barrat, J; Richomme, C; Moinet, M

    2010-04-01

    Exotic species have often been introduced into a new country in zoological or botanical gardens or on game and fur farms. When accidentally or deliberately released, these alien species can become invasive and have negative impacts on native plant and animal communities and human activities. This article focuses on a selection of such invasive species: principally the American mink (Neovison vison), but also the coypu (Myocastor coypus), muskrat (Ondatra zibethicus), raccoon dog (Nyctereutes procyonoides), raccoon (Procyon lotor) and African sacred ibis (Threskiornis aethiopicus). In each of these cases, the authors describe the biological characteristics and life history of the species, in relation to its invasive capacity, the origins and establishment of non-native populations, the environmental consequences and possible control measures. The main negative impacts observed are the destruction of habitat, the introduction and/or spread of pathogens and changes in the composition of native communities with consequent effects on biodiversity. PMID:20617652

  17. Regional scale atmospheric dispersion simulation of accidental releases of radionuclides from Fukushima Dai-ichi reactor

    NASA Astrophysics Data System (ADS)

    Srinivas, C. V.; Venkatesan, R.; Baskaran, R.; Rajagopal, V.; Venkatraman, B.

    2012-12-01

    This paper presents the results of regional scale atmospheric dispersion simulation of accidental emission of radionuclides from the Fukushima Daiichi Reactor, Japan following the Tohoku earthquake and tsunami event on 11 March 2011. The objective was to study the temporal behaviour of plume trajectory, concentration, deposition and radiation dose pattern over an 80 km range around the reactor. The time-varying meteorological parameters during the release period were simulated with a multi-scale nested atmospheric model WRF ARW and the trajectory, plume dispersion were computed with Lagrangian Particle Dispersion models HYSPLIT, FLEXPART using the available information on accidental source term. The simulations indicated that the wind flow over Japan during the release period was driven by the large scale extra-tropical westerly waves and associated low pressure systems. In the lower levels, the flow was influenced by the local topography/sea breeze causing occasional landward wind shift on the east coast of Japan. Simulated airflow trajectories revealed that the plume stayed over the ocean by westerly winds on most days and the radioactivity dispersed over sea surface. Landward trajectories were found on a few days due to southeasterly, easterly and northeasterly flow (15-17, 19-21 March 2011) during which much of the radionuclides deposited over the land region. The hotspot of depositions occurred over east Pacific Ocean near to Japan. Over the land relatively high depositions were simulated in a narrow zone of 20 km width and 80 km length in the northwest sector in agreement with monitor data. Simulations showed wet depositions over the land to be higher than the dry depositions during 12-30 March due to occurrence of rainfall on some days. Comparison of activity deposition and air dose values with available observations confirmed that the plume pattern in a finer length scale around the site could be simulated realistically and agree with the measurements

  18. Methodology for evaluation of possible consequences of accidental atmospheric releases of hazardous matter.

    PubMed

    Mahura, A; Baklanov, A; Sørensen, J Havskov

    2003-01-01

    Sites exist with high levels of risk of accidental atmospheric releases. These releases can be hazardous nuclear, chemical, and biological matter. Such accidents may occur during transport of waste, or they may be due to natural hazards, human errors, terror acts or various operations at high risk. Considering the operation of lifting and transport of the sunken Kursk nuclear submarine as an example, a methodology for risk assessment is described. This methodology includes two approaches: (1) probabilistic analysis of possible atmospheric transport pathways using trajectory modelling, and (2) evaluation of possible contamination and consequences using real-time operational atmospheric dispersion modelling. The first approach can be applied in advance of an operation during the preparation stage, the second in real time during the operation stage. For the cases considered in this study, the results of trajectory modelling are supported by the operational dispersion modelling, i.e., the westerly flow is dominant during fall occurring 79% of the time. Hence, September-October 2001 was more appropriate for the lifting and transport of the Kursk nuclear submarine in comparison with summer months, when atmospheric transport toward the populated regions of the Kola and Scandinavian Peninsulas was dominant. The suggested methodology may be applied to any potentially dangerous object involving a risk of atmospheric release of hazardous material of nuclear, chemical or biological nature. PMID:12593432

  19. [Prognosis of inhalation-related injuries in accidental release of ammonium and chlorine by the method of dynamic concentration].

    PubMed

    Litvinov, N N; Kazachkov, V I; Grigorevskaia, Z P; Tsygankov, S S; Iagund, G K; Bodanskiĭ, M D; Ivanov, A Iu; Shmelev, K V

    2000-01-01

    The article deals with new approaches to evaluate casualty effect of accidental chemical release exemplified by common and dangerous industrial chemicals ammonium and chlorine. Dynamic concentration method considers effects of high concentrations inducing instant reflex cardiac and respiratory arrest as well as lesions caused by variable toxic doses. PMID:11019541

  20. Modeling acute health risks associated with accidental releases of toxic gases

    SciTech Connect

    Haskin, F.E.; Ding, C.; Summa, K.J.; Young, M.

    1996-09-01

    CHEM{_}MACCS has been developed from the radiological accident consequence code, MACCS, to perform probabilistic calculations of potential off-site consequences of the accidental atmospheric release of hazardous chemicals. The principal phenomena considered in CHEM{_}MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways, and early and latent health effects. CHEM{_}MACCS provides the following capabilities: (1) statistical weather sampling data (8,760 hourly data points per year), (2) population dose and health effect risk calculations based on site-specific population data, (3) health effects calculations including the consideration of potential site specific mitigative actions (evacuation and shielding), and (4) modeling of multiple release segments. Three different sample problems are contained in this report to show how to use CHEM{_}MACCS. Three test problems are run to compare CHEM{_}MACCS and D2PC. The doses versus the downwind centerline distances from the source for the given doses are in very close agreement.

  1. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Schatz, K.W. ); Koopman, R.P. )

    1989-07-01

    Accidental releases of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher. 6 refs., 22 figs., 2 tabs.

  2. Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

    SciTech Connect

    Holve, D.J.; Harvill, T.L. )

    1989-06-01

    Accidental release of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid rates of 6/1 to 40/1 and higher. 8 refs., 69 figs., 50 tabs.

  3. Gas release in comet nuclei

    NASA Technical Reports Server (NTRS)

    Prialnik, Dina; Bar-Nun, Akiva

    1990-01-01

    Processes taking place during the evolution of a comet nucleus are examined, taking into account the release of gas on crystallization and the gas flow through the porous nucleus. In particular, the stresses caused by the gas pressure, the contribution of gas flow to the heat transfer, and the rate of gas emission by the comet along its orbit were determined using a model of spherically symmetric comet nucleus made of porous amorphous ice, with 10 percent CO gas trapped in it. Several values of density and pore size are considered, and for each combination of parameters, the model is evolved for 20-30 revolutions in Comet P/Halley's orbit. It is shown that a model of 0.2 g/cu cm density reproduces well many of the light-curve and activity characteristics of Comet P/Halley.

  4. Spill behaviour using REACTPOOL. Part II. Results for accidental releases of silicon tetrachloride (SiCl(4)).

    PubMed

    Kapias, T; Griffiths, R F; Stefanidis, C

    2001-02-16

    Silicon tetrachloride is a toxic, corrosive water reactive substance that is used widely in the process industries. On spillage from containment it creates liquid pools that can either boil or evaporate. The main feature of the pool behaviour is the exothermic reaction with water. There are three sources of water available for reaction: free ground water, substrate water and atmospheric moisture. Hydrogen chloride gas and ortho-silicic acid solid (or silica gel) are produced by the hydrolysis reaction. The purpose of this paper is to describe the dangers involved in cases of accidental releases of silicon tetrachloride, to report its properties, referring to toxicity data, major accidents and mitigation tests. It also describes pool behaviour using REACTPOOL [1]. Model results indicate that the pool behaviour is governed mainly by the amount of water available for reaction. Surface roughness and wind speed also have a significant effect on the results. Results are compared with those for other water reactive chemicals in Part III of this series of papers [3]. The generated cloud will initially contain silicon tetrachloride and hydrogen chloride with numerous processes taking place. Although silicon tetrachloride has been involved in many major hazard incidents, there are no experimental data relevant to the modelling requirements. PMID:11163688

  5. Dose Calculation For Accidental Release Of Radioactive Cloud Passing Over Jeddah

    NASA Astrophysics Data System (ADS)

    Alharbi, N. D.; Mayhoub, A. B.

    2011-12-01

    For the evaluation of doses after the reactor accident, in particular for the inhalation dose, a thorough knowledge of the concentration of the various radionuclide in air during the passage of the plume is required. In this paper we present an application of the Gaussian Plume Model (GPM) to calculate the atmospheric dispersion and airborne radionuclide concentration resulting from radioactive cloud over the city of Jeddah (KSA). The radioactive cloud is assumed to be emitted from a reactor of 10 MW power in postulated accidental release. Committed effective doses (CEDs) to the public at different distance from the source to the receptor are calculated. The calculations were based on meteorological condition and data of the Jeddah site. These data are: pasquill atmospheric stability is the class B and the wind speed is 2.4m/s at 10m height in the N direction. The residence time of some radionuclides considered in this study were calculated. The results indicate that, the values of doses first increase with distance, reach a maximum value and then gradually decrease. The total dose received by human is estimated by using the estimated values of residence time of each radioactive pollutant at different distances.

  6. The effectiveness of stationary automobiles as shelters in accidental releases of toxic materials

    NASA Astrophysics Data System (ADS)

    Engelmann, Rudolf J.; Pendergrass, William R.; White, J. Randy; Hall, Mark E.

    The protection offered occupants of stationary automobiles against airborne gases and respirable particles, such as might result from an accidental release, was measured and found to be substantial. For the four autos tested with the air conditioning (AC) system on and in recirculate position, the equilibrium ratios of inside/outside concentrations ( I/ O) for 2-μm diameter particles were less than 0.2, and some ratios were as small as 0.014. With both the AC compressor and the system fan off, the I/ O for five autos ranged from 0.04 to 0.18. These low ratios are primarily a result of deposition within the autos. However, three of the five autos had substantially higher I/ O ratios when the AC fan was on than when off, indicating that for some autos the AC caused significant added intake of outside air. Air exchange rates for the five stationary autos were on the order of 0.5h -1 with AC off, and 2.5 h -1 with AC on.

  7. Game theory of pre-emptive vaccination before bioterrorism or accidental release of smallpox.

    PubMed

    Molina, Chai; Earn, David J D

    2015-06-01

    Smallpox was eradicated in the 1970s, but new outbreaks could be seeded by bioterrorism or accidental release. Substantial vaccine-induced morbidity and mortality make pre-emptive mass vaccination controversial, and if vaccination is voluntary, then there is a conflict between self- and group interests. This conflict can be framed as a tragedy of the commons, in which herd immunity plays the role of the commons, and free-riding (i.e. not vaccinating pre-emptively) is analogous to exploiting the commons. This game has been analysed previously for a particular post-outbreak vaccination scenario. We consider several post-outbreak vaccination scenarios and compare the expected increase in mortality that results from voluntary versus imposed vaccination. Below a threshold level of post-outbreak vaccination effort, expected mortality is independent of the level of response effort. A lag between an outbreak starting and a response being initiated increases the post-outbreak vaccination effort necessary to reduce mortality. For some post-outbreak vaccination scenarios, even modest response lags make it impractical to reduce mortality by increasing post-outbreak vaccination effort. In such situations, if decreasing the response lag is impossible, the only practical way to reduce mortality is to make the vaccine safer (greater post-outbreak vaccination effort leads only to fewer people vaccinating pre-emptively). PMID:25926701

  8. Dose Calculation For Accidental Release Of Radioactive Cloud Passing Over Jeddah

    SciTech Connect

    Alharbi, N. D.; Mayhoub, A. B.

    2011-12-26

    For the evaluation of doses after the reactor accident, in particular for the inhalation dose, a thorough knowledge of the concentration of the various radionuclide in air during the passage of the plume is required. In this paper we present an application of the Gaussian Plume Model (GPM) to calculate the atmospheric dispersion and airborne radionuclide concentration resulting from radioactive cloud over the city of Jeddah (KSA). The radioactive cloud is assumed to be emitted from a reactor of 10 MW power in postulated accidental release. Committed effective doses (CEDs) to the public at different distance from the source to the receptor are calculated. The calculations were based on meteorological condition and data of the Jeddah site. These data are: pasquill atmospheric stability is the class B and the wind speed is 2.4m/s at 10m height in the N direction. The residence time of some radionuclides considered in this study were calculated. The results indicate that, the values of doses first increase with distance, reach a maximum value and then gradually decrease. The total dose received by human is estimated by using the estimated values of residence time of each radioactive pollutant at different distances.

  9. Game theory of pre-emptive vaccination before bioterrorism or accidental release of smallpox

    PubMed Central

    Molina, Chai; Earn, David J. D.

    2015-01-01

    Smallpox was eradicated in the 1970s, but new outbreaks could be seeded by bioterrorism or accidental release. Substantial vaccine-induced morbidity and mortality make pre-emptive mass vaccination controversial, and if vaccination is voluntary, then there is a conflict between self- and group interests. This conflict can be framed as a tragedy of the commons, in which herd immunity plays the role of the commons, and free-riding (i.e. not vaccinating pre-emptively) is analogous to exploiting the commons. This game has been analysed previously for a particular post-outbreak vaccination scenario. We consider several post-outbreak vaccination scenarios and compare the expected increase in mortality that results from voluntary versus imposed vaccination. Below a threshold level of post-outbreak vaccination effort, expected mortality is independent of the level of response effort. A lag between an outbreak starting and a response being initiated increases the post-outbreak vaccination effort necessary to reduce mortality. For some post-outbreak vaccination scenarios, even modest response lags make it impractical to reduce mortality by increasing post-outbreak vaccination effort. In such situations, if decreasing the response lag is impossible, the only practical way to reduce mortality is to make the vaccine safer (greater post-outbreak vaccination effort leads only to fewer people vaccinating pre-emptively). PMID:25926701

  10. Exhaled nitric oxide in children after accidental exposure to chlorine gas.

    PubMed

    Grasemann, Hartmut; Tschiedel, Eva; Groch, Manuela; Klepper, Jörg; Ratjen, Felix

    2007-08-01

    Chronic exposure to chlorine gas has been shown to cause occupational asthma. Acute inhalation of chlorine is known to cause airway inflammation and induce airway nitric oxide formation. Exhaled nitric oxide may therefore be a marker of airway damage after chlorine gas exposure. After accidental chlorine gas exposure in a swimming pool, exhaled nitric oxide and pulmonary function were repeatedly measured in 18 children over a 1-mo period. Symptomatic children with impaired pulmonary function had higher nitric oxide levels on the day after the exposure compared to day 8 and day 28. Differences in exhaled nitric oxide were more pronounced at a higher exhalation flow compared to lower flow, suggesting peripheral rather than central airway damage. This was in accordance with the observed changes in pulmonary function. No changes in exhaled nitric oxide were seen in asymptomatic children. These data suggest that acute chlorine gas exposure results in a mild increase of exhaled nitric oxide in symptomatic children. PMID:17687720

  11. Historical Doses To The Public from Routine and Accidental Releases of Tritium - Lawrence Livermore National Laboratory, 1953 - 2005

    SciTech Connect

    Peterson, S; Raskob, W

    2007-08-15

    Throughout fifty-three years of operations, an estimated 29,300 TBq of tritium have been released to the atmosphere at the Livermore site of Lawrence Livermore National Laboratory; about 75% of this was released accidentally as gaseous tritium in 1965 and 1970. Routine emissions contributed slightly more than 3,700 TBq gaseous tritium and about 2,800 TBq tritiated water vapor to the total. Mean annual doses (with 95% confidence intervals) to the most exposed member of the public were calculated for all years using the same model and the same assumptions. Because time-dependent tritium models require detailed meteorological data that were unavailable for the large releases, ingestion/inhalation dose ratios were derived from experience with UFOTRI. Even with assumptions to assure that doses would not be underestimated, all doses from routine and accidental releases were below the level (3.6 mSv) at which adverse health effects have been documented, and most were below the current regulatory limit of 100 {micro}Sv per year from releases to the atmosphere.

  12. Gas release in comet nuclei.

    PubMed

    Prialnik, D; Bar-Nun, A

    1990-11-01

    The evolution of a comet nucleus is investigated, taking into account the crystallization process by which the gas trapped in the ice is released to flow through the porous ice matrix. The equations of conservation of the energy and of the masses of ice and gas are solved throughout the nucleus, to obtain the evolution of the temperature, gas pressure and density profiles. A spherical nucleus composed of cold, porous amorphous ice, with 10% of CO trapped in it, serves as initial model. Several values of density (porosity) and pore size are considered. For each combination of parameters the model is evolved for 20-30 revolutions in comet P/Halley's orbit. Two aspects of the release of gas upon crystallization are analyzed and discussed: (a) the resulting continuous outward flux with high peaks at the time of crystallization, which is a cyclic process in the low-density models and sporadic in the high-density ones; (b) the internal pressures obtained down to depths of a few tens to approximately 200 m (depending on parameters), that are found to exceed the compressional strength of cometary ice. As a result, both cracking and explosions of the overlying ice layer and ejection of gas and ice/dust grains are expected to follow crystallization. They should appear as outbursts or sudden brightening of the comet. The model of 0.2 g cm-3 density is found to reproduce quite well many of the light-curve and activity characteristics of comet P/Halley. PMID:11538699

  13. Long-term environmental fate of perfluorinated compounds after accidental release at Toronto airport.

    PubMed

    Awad, Emily; Zhang, Xianming; Bhavsar, Satyendra P; Petro, Steve; Crozier, Patrick W; Reiner, Eric J; Fletcher, Rachael; Tittlemier, Sheryl A; Braekevelt, Eric

    2011-10-01

    Perfluorooctane sulfonate (PFOS; a perfluorinated compound or PFC), its salts, and perfluorooctane sulfonyl fluoride have recently been listed in Annex B of the Stockholm Convention due to their widespread presence, persistence, and toxicity. Because of the persistent nature of PFCs, it is generally presumed that the impact of direct discharges of these chemicals on a receiving environment would be long-lasting. However, long-term environmental fate studies based on field measurements are rare. We examined spatial and long-term (9 year) temporal trends of PFCs in water, sediment, fish, and fish liver collected in 2003, 2006, and 2009 from 10 locations spanning ∼20 km in Etobicoke and Spring Creeks, where an accidental release of fire fighting foam containing PFOS from nearby Toronto International Airport occurred in 2000. Even a decade after the spill, sediment PFOS concentrations are still elevated in Spring Creek Pond which received the foam discharge; however, the major impact is relatively localized likely due to the stormwater management nature of the pond and the diluting effect of Etobicoke Creek. Fish and fish liver PFOS concentrations at a Spring Creek location downstream of Spring Creek Pond declined by about 70 and 85%, respectively, between 2003 and 2009. PFOS in water at locations further downstream in Etobicoke Creek have declined by >99.99% since the spill; however, the 2009 water and fish levels were ∼2-10 times higher than upstream locations likely due to the long-term impact of the spill as well as urbanization. The decrease in the upstream PFOS concentrations likely reflects the reduction of PFOS sources due to phased out production by 3M and regulations on the use of PFOS in fire fighting foams. Field-based sediment/water distribution coefficients (K(D)) and bioaccumulation factors (BAF) were calculated from environmental measurements. Log K(D) values were 0.54-1.65 for perfluoroalkyl sulfonates (PFASs) and 1.00-1.85 for

  14. A screening tool to prioritize public health risk associated with accidental or deliberate release of chemicals into the atmosphere

    PubMed Central

    2013-01-01

    The Chemical Events Working Group of the Global Health Security Initiative has developed a flexible screening tool for chemicals that present a risk when accidentally or deliberately released into the atmosphere. The tool is generic, semi-quantitative, independent of site, situation and scenario, encompasses all chemical hazards (toxicity, flammability and reactivity), and can be easily and quickly implemented by non-subject matter experts using freely available, authoritative information. Public health practitioners and planners can use the screening tool to assist them in directing their activities in each of the five stages of the disaster management cycle. PMID:23517410

  15. An integrated decision model for the application of airborne sensors for improved response to accidental and terrorist chemical vapor releases

    NASA Astrophysics Data System (ADS)

    Kapitan, Loginn

    This research created a new model which provides an integrated approach to planning the effective selection and employment of airborne sensor systems in response to accidental or intentional chemical vapor releases. The approach taken was to use systems engineering and decision analysis methods to construct a model architecture which produced a modular structure for integrating both new and existing components into a logical procedure to assess the application of airborne sensor systems to address chemical vapor hazards. The resulting integrated process model includes an internal aggregation model which allowed differentiation among alternative airborne sensor systems. Both models were developed and validated by experts and demonstrated using appropriate hazardous chemical release scenarios. The resultant prototype integrated process model or system fills a current gap in capability allowing improved planning, training and exercise for HAZMAT teams and first responders when considering the selection and employment of airborne sensor systems. Through the research process, insights into the current response structure and how current airborne capability may be most effectively used were generated. Furthermore, the resultant prototype system is tailorable for local, state, and federal application, and can potentially be modified to help evaluate investments in new airborne sensor technology and systems. Better planning, training and preparedness exercising holds the prospect for the effective application of airborne assets for improved response to large scale chemical release incidents. Improved response will result in fewer casualties and lives lost, reduced economic impact, and increased protection of critical infrastructure when faced with accidental and intentional terrorist release of hazardous industrial chemicals. With the prospect of more airborne sensor systems becoming available, this prototype system integrates existing and new tools into an effective

  16. Effects of meteorological conditions on the concentration and dispersion of an accidental release of H2S in Canada

    NASA Astrophysics Data System (ADS)

    Abdul-Wahab, Sabah A.; Chan, Keziah; Elkamel, Ali; Ahmadi, Lena

    2014-01-01

    This study aims to determine the effects of the land's meteorological conditions on the dispersion of an accidental release of H2S using the CALPro software. The three Canadian cities or towns of Edmonton, Yarmouth and Whitehorse, which are all of different meteorological conditions, were chosen as the domains of study. Hourly geophysical, surface and upper air meteorological data were used with CALMET to model the wind field of the three domains for the modeling period of March 11, 2012 from 00h00 to 23h00 LST. Individual 5-h modeling periods where the wind field showed the most significant variations were chosen for each region of study. CALPUFF was used to model the dispersion effects of an accidental release of H2S from a single point source due to an accidental vessel puncture using time-varying emission data modified to suit each region's modeling period. Despite the wind reversal encountered in Edmonton, its relatively flat terrain allowed H2S to disperse outwards, causing concentrations to accumulate lower than the other two regions but still to sever levels and a much greater population. Differences between the effect of land and sea breeze on H2S dispersion in Yarmouth's coastal region caused concentrations to accumulate higher than the other two regions and to life threatening levels around the source. The mountainous terrain of Whitehorse shaped the plume trajectory, causing H2S concentrations to accumulate to levels that can cause irreversible health effects at various times and locations. Results show that each area's meteorological conditions will have different impacts on dispersion.

  17. Final Report: Safety of Plasma Components and Aerosol Transport During Hard Disruptions and Accidental Energy Release in Fusion Reactor

    SciTech Connect

    Bourham, Mohamed A.; Gilligan, John G.

    1999-08-14

    Safety considerations in large future fusion reactors like ITER are important before licensing the reactor. Several scenarios are considered hazardous, which include safety of plasma-facing components during hard disruptions, high heat fluxes and thermal stresses during normal operation, accidental energy release, and aerosol formation and transport. Disruption events, in large tokamaks like ITER, are expected to produce local heat fluxes on plasma-facing components, which may exceed 100 GW/m{sup 2} over a period of about 0.1 ms. As a result, the surface temperature dramatically increases, which results in surface melting and vaporization, and produces thermal stresses and surface erosion. Plasma-facing components safety issues extends to cover a wide range of possible scenarios, including disruption severity and the impact of plasma-facing components on disruption parameters, accidental energy release and short/long term LOCA's, and formation of airborne particles by convective current transport during a LOVA (water/air ingress disruption) accident scenario. Study, and evaluation of, disruption-induced aerosol generation and mobilization is essential to characterize database on particulate formation and distribution for large future fusion tokamak reactor like ITER. In order to provide database relevant to ITER, the SIRENS electrothermal plasma facility at NCSU has been modified to closely simulate heat fluxes expected in ITER.

  18. Towards the operational estimation of a radiological plume using data assimilation after a radiological accidental atmospheric release

    NASA Astrophysics Data System (ADS)

    Winiarek, Victor; Vira, Julius; Bocquet, Marc; Sofiev, Mikhail; Saunier, Olivier

    2011-06-01

    In the event of an accidental atmospheric release of radionuclides from a nuclear power plant, accurate real-time forecasting of the activity concentrations of radionuclides is required by the decision makers for the preparation of adequate countermeasures. The accuracy of the forecast plume is highly dependent on the source term estimation. On several academic test cases, including real data, inverse modelling and data assimilation techniques were proven to help in the assessment of the source term. In this paper, a semi-automatic method is proposed for the sequential reconstruction of the plume, by implementing a sequential data assimilation algorithm based on inverse modelling, with a care to develop realistic methods for operational risk agencies. The performance of the assimilation scheme has been assessed through the intercomparison between French and Finnish frameworks. Two dispersion models have been used: Polair3D and Silam developed in two different research centres. Different release locations, as well as different meteorological situations are tested. The existing and newly planned surveillance networks are used and realistically large multiplicative observational errors are assumed. The inverse modelling scheme accounts for strong error bias encountered with such errors. The efficiency of the data assimilation system is tested via statistical indicators. For France and Finland, the average performance of the data assimilation system is strong. However there are outlying situations where the inversion fails because of a too poor observability. In addition, in the case where the power plant responsible for the accidental release is not known, robust statistical tools are developed and tested to discriminate candidate release sites.

  19. Investigation of an Accidental Radiological Release in an Underground Disposal Facility.

    PubMed

    Poppiti, James; Sheffield, Ryan

    2016-02-01

    A radioactive release took place at the Waste Isolation Pilot Plant near Carlsbad, New Mexico, on 14 February 2014. An alarm from a Continuous Air Monitor caused a switch from unfiltered to filtered air exiting the facility through High-Efficiency Particulate Arrestance filters. The activity measured on the filters demonstrated first order decay, indicating that the release was a single release. The facility was reentered in April 2014 and photographic evidence pointed to a single breached 55-gallon drum that originated at Los Alamos as the source of the release. Data were collected and analyzed to verify the source and cause of the release. PMID:26710163

  20. Morphology of Gas Release in Physical Simulants

    SciTech Connect

    Daniel, Richard C.; Burns, Carolyn A.; Crawford, Amanda D.; Hylden, Laura R.; Bryan, Samuel A.; MacFarlan, Paul J.; Gauglitz, Phillip A.

    2014-07-03

    This report documents testing activities conducted as part of the Deep Sludge Gas Release Event Project (DSGREP). The testing described in this report focused on evaluating the potential retention and release mechanisms of hydrogen bubbles in underground radioactive waste storage tanks at Hanford. The goal of the testing was to evaluate the rate, extent, and morphology of gas release events in simulant materials. Previous, undocumented scoping tests have evidenced dramatically different gas release behavior from simulants with similar physical properties. Specifically, previous gas release tests have evaluated the extent of release of 30 Pa kaolin and 30 Pa bentonite clay slurries. While both materials are clays and both have equivalent material shear strength using a shear vane, it was found that upon stirring, gas was released immediately and completely from bentonite clay slurry while little if any gas was released from the kaolin slurry. The motivation for the current work is to replicate these tests in a controlled quality test environment and to evaluate the release behavior for another simulant used in DSGREP testing. Three simulant materials were evaluated: 1) a 30 Pa kaolin clay slurry, 2) a 30 Pa bentonite clay slurry, and 3) Rayleigh-Taylor (RT) Simulant (a simulant designed to support DSGREP RT instability testing. Entrained gas was generated in these simulant materials using two methods: 1) application of vacuum over about a 1-minute period to nucleate dissolved gas within the simulant and 2) addition of hydrogen peroxide to generate gas by peroxide decomposition in the simulants over about a 16-hour period. Bubble release was effected by vibrating the test material using an external vibrating table. When testing with hydrogen peroxide, gas release was also accomplished by stirring of the simulant.

  1. Wind tunnel modeling of toxic gas releases at industrial facilities

    SciTech Connect

    Petersen, R.L.

    1994-12-31

    Government agencies and the petroleum, chemical and gas industries in the US and abroad have become increasingly concerned about the issues of toxic gas dispersal. Because of this concern, research programs have been sponsored by these various groups to improve the capabilities in hazard mitigation and response. Present computer models used to predict pollutant concentrations at industrial facilities do not properly account for the effects of structures. Structures can act to trap or deflect the cloud and modify the cloud dimensions, thereby possibly increasing or reducing downwind concentrations. The main purpose of this evaluation was to develop a hybrid modeling approach, which combines wind tunnel and dispersion modeling, to obtain more accurate concentration estimates when buildings or structures affect the dispersion of hazardous chemical vapors. To meet the study objectives, wind tunnel testing was performed on a building cluster typical of two industrial settings where accidental releases of toxic gases might occur. This data set was used to test the validity of the AFTOX and SLAB models for estimating concentrations and was used to develop and test two hybrid models. Two accident scenarios were simulated, an evaporating pool of a gas slightly heavier than air (Hydrazine-N{sub 2}H{sub 4}) and a liquid jet release of Nitrogen Tetroxide (N{sub 2}O{sub 4}) where dense gas dispersion effects would be significant. Tests were conducted for a range of wind directions and wind speeds for two different building configurations (low rise and high rise structures).

  2. Evidence Theory Based Uncertainty Quantification in Radiological Risk due to Accidental Release of Radioactivity from a Nuclear Power Plant

    SciTech Connect

    Ingale, S. V.; Datta, D.

    2010-10-26

    Consequence of the accidental release of radioactivity from a nuclear power plant is assessed in terms of exposure or dose to the members of the public. Assessment of risk is routed through this dose computation. Dose computation basically depends on the basic dose assessment model and exposure pathways. One of the exposure pathways is the ingestion of contaminated food. The aim of the present paper is to compute the uncertainty associated with the risk to the members of the public due to the ingestion of contaminated food. The governing parameters of the ingestion dose assessment model being imprecise, we have approached evidence theory to compute the bound of the risk. The uncertainty is addressed by the belief and plausibility fuzzy measures.

  3. A CASE STUDY OF CHLORINE TRANSPORT AND FATE FOLLOWING A LARGE ACCIDENTAL RELEASE

    SciTech Connect

    Buckley, R.; Hunter, C.; Werth, D.; Whiteside, M.; Chen, K.; Mazzola, C.

    2012-08-01

    A train derailment that occurred in Graniteville, South Carolina during the early morning hours of 06 January, 2005 resulted in the prompt release of approximately 60 tons of chlorine to the environment. Comprehensive modeling of the transport and fate of this release was performed including the characterization of the initial three-phased chlorine release, a detailed determination of the local atmospheric conditions acting to generate, disperse, and deplete the chlorine vapor cloud, the establishment of physical exchange mechanisms between the airborne vapor and local surface waters, and local aquatic dilution and mixing.

  4. Prevention reference manual: chemical specific. Volume 2. Control of accidental releases of chlorine (SCAQMD) (South Coast Air Quality Management District). Final report, May 1986-March 1987

    SciTech Connect

    Davis, D.S.; DeWolf, G.B.; Quass, J.D.; Wert, K.P.

    1987-07-01

    This manual discusses reducing the risk associated with an accidental release of chlorine. It identifies some of the potential causes of accidental releases that apply to the processes that use chlorine. It also identifies examples of potential causes, as well as measures that may be taken to reduce the accidental release risk. Such measures include recommendations on: plant design practices; prevention, protection, and mitigation technologies; and operation and maintenance practices. It provides conceptual cost estimates of possible prevention, protection, and mitigation measures. Chlorine is a highly reactive and corrosive liquid that boils at room temperature. It has an IDLH (immediately dangerous to life and health) concentration of 25 ppm, which makes it a substantial acute toxic hazard. Accidental releases of toxic chemicals at Bhopal and Chernobyl have increased public awareness of toxic-release problems. As a result of other, perhaps less-dramatic incidents in the past, portions of the chemical industry were aware of this problem long before these events. These same portions of the industry have made advances in the area.

  5. Accidental Release of Chlorine from a Storage Facility and an On-Site Emergency Mock Drill: A Case Study.

    PubMed

    Soman, Ambalathumpara Raman; Sundararaj, Gopalswamy

    2015-01-01

    In the current industrial scenario there is a serious need for formulating strategies to handle hazardous substances in the safest way. Manufacture, storage, and use of hazardous substances pose a serious risk to industry, people, and the environment. Accidental release of toxic chemicals can lead to emergencies. An emergency response plan (ERP) is inevitable to minimize the adverse effects of such releases. The on-site emergency plan is an integral component of any process safety and risk management system. This paper deals with an on-site emergency response plan for a chlorine manufacturing industry. It was developed on the basis of a previous study on chlorine release and a full scale mock drill has been conducted for testing the plan. Results indicated that properly trained personnel can effectively handle each level of incidents occurring in the process plant. As an extensive guideline to the district level government authorities for off-site emergency planning, risk zone has also been estimated with reference to a chlorine exposure threshold of 3 ppm. PMID:26171416

  6. Accidental Release of Chlorine from a Storage Facility and an On-Site Emergency Mock Drill: A Case Study

    PubMed Central

    Soman, Ambalathumpara Raman; Sundararaj, Gopalswamy

    2015-01-01

    In the current industrial scenario there is a serious need for formulating strategies to handle hazardous substances in the safest way. Manufacture, storage, and use of hazardous substances pose a serious risk to industry, people, and the environment. Accidental release of toxic chemicals can lead to emergencies. An emergency response plan (ERP) is inevitable to minimize the adverse effects of such releases. The on-site emergency plan is an integral component of any process safety and risk management system. This paper deals with an on-site emergency response plan for a chlorine manufacturing industry. It was developed on the basis of a previous study on chlorine release and a full scale mock drill has been conducted for testing the plan. Results indicated that properly trained personnel can effectively handle each level of incidents occurring in the process plant. As an extensive guideline to the district level government authorities for off-site emergency planning, risk zone has also been estimated with reference to a chlorine exposure threshold of 3 ppm. PMID:26171416

  7. Code System for Calculating Radiation Exposure Resulting from Accidental Radioactive Releases to the Hydrosphere.

    1982-11-18

    Version 00 LPGS was developed to calculate the radiological impacts resulting from radioactive releases to the hydrosphere. The name LPGS was derived from the Liquid Pathway Generic Study for which the original code was used primarily as an analytic tool in the assessment process. The hydrosphere is represented by the following types of water bodies: estuary, small river, well, lake, and one-dimensional (1-D) river. LPGS is designed to calculate radiation dose (individual and population) tomore » body organs as a function of time for the various exposure pathways. The radiological consequences to the aquatic biota are estimated. Several simplified radionuclide transport models are employed with built-in formulations to describe the release rate of the radionuclides. A tabulated user-supplied release model can be input, if desired. Printer plots of dose versus time for the various exposure pathways are provided.« less

  8. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 3. CONTROL OF ACCIDENTAL RELEASES OF HYDROGEN CYANIDE (SCAQMD) (SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT)

    EPA Science Inventory

    The report discusses a strategy (being considered by the South Coast Air Quality Management District--SCAQMD--of Southern California) for reducing the risk of a major accidental air release of toxic chemicals. The strategy, intended to guide both industry and communities, consist...

  9. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  10. The potential for damage from the accidental release of conductive carbon fibers from burning composites

    NASA Technical Reports Server (NTRS)

    Bell, V. L.

    1980-01-01

    The potential damage to electrical equipment caused by the release of carbon fibers from burning commercial airliners is assessed in terms of annual expected costs and maximum losses at low probabilities of occurrence. A materials research program to provide alternate or modified composite materials for aircraft structures is reviewed.

  11. A case study of chlorine transport and fate following a large accidental release

    NASA Astrophysics Data System (ADS)

    Buckley, Robert L.; Hunter, Charles H.; Werth, David W.; Whiteside, Morgana T.; Chen, Kuo-Fu; Mazzola, Carl A.

    2012-12-01

    A train derailment that occurred in Graniteville, South Carolina during the early morning hours of 06 January, 2005 resulted in the prompt release of approximately 60 tons of chlorine to the environment. Comprehensive modeling of the transport and fate of this release was performed including the characterization of the initial three-phased chlorine release, a detailed determination of the local atmospheric conditions acting to generate, disperse, and deplete the chlorine vapor cloud, the establishment of physical exchange mechanisms between the airborne vapor and local surface waters, and local aquatic dilution and mixing.Previous studies of large chlorine releases have concluded that depletion of the resulting vapor cloud through physical and chemical reactions with sunlight, atmospheric constituents, and local surfaces can significantly reduce the areal extent over which the vapor poses a toxicological hazard. For Graniteville, modeling results were the most consistent with available data on human health effects, animal and fish mortality, and vegetation damage when an effective deposition velocity in the lower end of a range of values commonly cited in other studies (1 cm s-1) was applied. This relatively small deposition is attributed to a lack of sunlight, a limited uptake in vegetation due to rapid stomatal damage, and the limited presence of nearby man-made structures. Explicit simulations of chlorine deposition into adjacent surface waters were based on a modified Henry's Law approach and resulted in the transfer of an estimated 21 kg of chlorine into these waters.

  12. Estimation of the dispersion of an accidental release of radionuclides and toxic materials based on weather type classification

    NASA Astrophysics Data System (ADS)

    Mészáros, Róbert; Leelőssy, Ádám; Vincze, Csilla; Szűcs, Mihály; Kovács, Tibor; Lagzi, István

    2012-02-01

    We investigate the influence of the regional-scale weather types on the atmospheric dispersion processes of the air pollutants originated from point sources. Hypothetical accidents were simulated with two different dispersion models. During a year's test period, the 6-h emission of a radionuclide from the Paks Nuclear Power Plant (Paks NPP, Hungary) was assumed every day and the transport and deposition of the radionuclide was simulated by the Eulerian TREX dispersion model over the Central European region. In addition, the ALOHA Gaussian air dispersion model was also used for the local environment of the Paks NPP to simulate hypothetical hourly releases of ammonia during a 10-year period. During both types of model simulations, the dispersion of the plume for each time was analysed and tested with consideration of 13 circulation types corresponding to daily weather patterns over the Carpathian Basin. There are significant correlations between circulation types and plume directions and structures both in local and regional scales. The daily circulation pattern can be easily obtained from weather analyses; the expected size and direction of polluted area after an accidental release can be quickly estimated even before an accident occurs. However, this fast method cannot replace or neglect dispersion model simulations. It gives a `first guess' and a fast estimation on the direction of the plume and can provide sufficient information for decision-making strategies.

  13. Partitioning of perfluorooctanesulfonate and perfluorohexanesulfonate in the aquatic environment after an accidental release of aqueous film forming foam at Schiphol Amsterdam Airport.

    PubMed

    Kwadijk, Christiaan J A F; Kotterman, Michiel; Koelmans, Albert A

    2014-08-01

    In summer 2008, an accidental release of aqueous film forming foam (AFFF) took place at Schiphol Amsterdam Airport (The Netherlands). After the release, water, fish, and sediment samples were collected and analyzed for perfluoroalkyl sulfonates (PFSAs). In situ perfluorooctane sulfonate (PFOS) sediment-water distribution factor (KD ) values, bioaccumulation factor (BAF) values, and biota-sediment accumulation factor (BSAF) values showed a remarkable agreement among reference and impacted sites, 10 wk after the incident as well as after 3 yr. PMID:24729487

  14. Consequence analysis for accidental releases of toxic substances in a complex terrain with shoreline in Korea

    SciTech Connect

    Ghim, Y.S.; Oh, H.S.; Moon, K.C.

    1999-07-01

    Offsite consequences resulting from various scenarios involving release of toxic substances in the Yochon Industrial Estate located in the Yosu Peninsula with complex terrain and intricate shorelines are estimated using ALOHA (Areal Locations of Hazardous Atmospheres) and RAMS (Regional Atmospheric Modeling System). ALOHA analyses by assuming the worst-case release scenarios for selected chemicals in the worst-case and alternative meteorological conditions indicate the impact on several thousand people in the nearby area. RAMS simulation is performed in order to consider the influence of terrain and shoreline. Receptors behind the terrain, 5 to 6 km distant from the source, also show high concentration when the wind blows to the terrain as well as receptors in front of the terrain in the nearby area. With considering the diurnal variations of meteorological variables, it is predicted that complicated wind patterns with low speeds could cause high concentration over the entire area adjacent to the Estate.

  15. Modeling the wind-fields of accidental releases with an operational regional forecast model

    SciTech Connect

    Albritton, J.R.; Lee, R.L.; Sugiyama, G.

    1995-09-11

    The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC`s operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-field scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC`s real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-field for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational Regional Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows.

  16. PEAR - public exposure from accidental releases: software package EI-028-S86

    SciTech Connect

    Not Available

    1988-01-01

    PEAR is a digital computer program developed to calculate radiation doses to an individual or population in the path of a plume of airborne radioactive materials released into the atmosphere following an accident at a nuclear facility. The code uses the methodology described in the CSA standard N288.2 Guidelines for calculation of radiation doses to the public from a release of airborne radioactive material under accident conditions in nuclear facilities. The code calculates internal and external dose equivalent (to organs and effective) and factors in the specific meteorological and topographical conditions of the site and the specific characteristics of the releases. It deals with 38 radionuclides and with mixtures of radioisotopes. The code is useful for the evaluation of the effects of postulated accidents (such as in the safety reports) and as a real time analysis tool for emergency planning exercises and actual accidents, should they occur. It is relatively easy to run as it is based on a strong interaction between the computer and the user and has easy access to data files.

  17. Estimating outdoor and indoor dust lead levels from accidental bridge repair containment releases

    SciTech Connect

    Cohen, J.T.; Conway, R.F.

    1999-07-01

    A 1998 New York City Department of Transportation (NYCDOT) environmental impact statement (EIS) evaluated the proposed removal of deteriorated lead paint from NYCDOT-owned bridges. The EIS health risk assessment quantified the potential impact of particulate releases on blood lead levels among members of the public living and working near affected bridges. The risk assessment consisted of a fate and transport component and an exposure-dose component. The fate and transport component, modeled using the EPA's Industrial Source Complex (ISC3) model, calculated the impact of paint removal activities on ambient air lead concentrations and dust lead deposition rates. The exposure-dose component, modeled using EPA's Integrated Exposure Uptake Biokinetic (IEUBK) model, the Bowers et al. Adult Lead model, and the O'Flaherty lead model, calculated the impact of additional lead in air, street dust, interior house dust, and soil on blood lead levels, a conventional measure of body lead burden. The analysis was complicated because the ISC3 model provides a dust lead deposition rate ({micro}g/m{sup 2}-day), while the IEUBK, Bowers et al., and O'Flaherty models demand as input specification of dust lead concentrations ({micro}g lead per g dust). This paper describes a model developed for the EIS that quantifies long term average dust lead concentrations associated with typical bridge containment releases, and short term dust lead concentration spikes following worst case release events associated with bridge repair containment structure failures. The model reflects the influence of both lead and other debris associated with bridge repair activities, the contribution of background debris to street dust, and the impact of rainfall on removal of both lead and other material from the street dust reservoir.

  18. Modeling the wind-fields of accidental releases by mesoscale forecasting

    SciTech Connect

    Albritton, J.R.; Lee, R.L.; Mobley, R.L.; Pace, J.C.; Hodur, R.A.; Lion, C.S.

    1997-07-01

    Modeling atmospheric releases even during fair weather can present a sever challenge to diagnostic, observed-data-driven, models. Such schemes are often handicapped by sparse input data from meteorological surface stations and soundings. Forecasting by persistence is only acceptable for a few hours and cannot predict important changes in the diurnal cycle or from synoptic evolution. Many accident scenarios are data-sparse in space and/or time. Here we describe the potential value of limited-area, mesoscale, forecast models for real-time emergency response. Simulated wind-fields will be passed to ARAC`s operational models to produce improved forecasts of dispersion following accidents.

  19. Calculation of Doses Due to Accidentally Released Plutonium From An LMFBR

    SciTech Connect

    Fish, B.R.

    2001-08-07

    Experimental data and analytical models that should be considered in assessing the transport properties of plutonium aerosols following a hypothetical reactor accident have been examined. Behaviors of released airborne materials within the reactor containment systems, as well as in the atmosphere near the reactor site boundaries, have been semiquantitatively predicted from experimental data and analytical models. The fundamental chemistry of plutonium as it may be applied in biological systems has been used to prepare models related to the intake and metabolism of plutonium dioxide, the fuel material of interest. Attempts have been made to calculate the possible doses from plutonium aerosols for a typical analyzed release in order to evaluate the magnitude of the internal exposure hazards that might exist in the vicinity of the reactor after a hypothetical LMFBR (Liquid-Metal Fast Breeder Reactor) accident. Intake of plutonium (using data for {sup 239}Pu as an example) and its distribution in the body were treated parametrically without regard to the details of transport pathways in the environment. To the extent possible, dose-response data and models have been reviewed, and an assessment of their adequacy has been made so that recommended or preferred practices could be developed.

  20. Gas cylinder release rate testing and analysis

    NASA Astrophysics Data System (ADS)

    Despres, Joseph; Sweeney, Joseph; Yedave, Sharad; Chambers, Barry

    2012-11-01

    There are varying cylinder technologies employed for the storage of gases, each resulting in a potentially different hazard level to the surroundings in the event of a gas release. Subatmospheric Gas delivery Systems Type I (SAGS I) store and deliver gases subatmospherically, while Subatmospheric Gas delivery Systems Type II (SAGS II) deliver gases subatmospherically, but store them at high pressure. Standard high pressure gas cylinders store and deliver their contents at high pressure. Due to the differences in these cylinder technologies, release rates in the event of a leak or internal component failure, can vary significantly. This paper details the experimental and theoretical results of different Arsine (AsH3) gas cylinder release scenarios. For the SAGS II experimental analysis, Fourier Transform Infrared Spectroscopy (FTIR) was used to determine the spatial concentration profiles when a surrogate gas, CF4, was released via a simulated leak within an ion implanter. Various SAGS I and SAGS II cylinder types and failure modes were tested. Additionally, theoretical analysis was performed to support an understanding of the different potential AsH3 leak rates. The results of this work show that the effects of a leak from the various cylinder types can be quite different, with the concentrations resulting from cylinders containing high pressure gas often being in excess of IDLH levels.

  1. Beneficial impacts of the implementation of the accidental release risk management regulation

    SciTech Connect

    Nand, K.

    1999-07-01

    The US Environmental Protection Agency (EPA) Risk Management Program and Plan (RMP) regulations were issued on June 20, 1996, which require the implementation of a Risk Management Program by June 21, 1999. These regulations are designed to prevent serious chemical accidents that could affect public health and the environment and to improve the response to any accidents that do occur. The RMP regulations have forced various industries handling regulated substances to review their operations and develop measures to prevent accidents, reduce the quantity of regulated substance released during an accident, reduce the quantity stored at the facility or completely eliminate the use of the regulated substance. The net result of these actions will be to overall reduce the risk and cause beneficial impacts to the surrounding community. A review analysis was performed of the various actions, including the control measures implemented by various facilities to prevent the accidents and reduce the overall risk as part of the implementation of RMP regulations. The results of the review analysis indicated that for some of the facilities the best control measure would be to substitute the regulated substance with a less hazardous material. For example, anhydrous chlorine may be replaced by sodium hypochlorite for water and wastewater disinfection purposes.

  2. Study of the effects of accidentally released carbon/graphite fibers on electric power equipment. Program final report, June 5, 1978-June 5, 1980

    SciTech Connect

    Mauser, S.F.; Bankoske, J.W.; Cooper, J.H.; Davies, D.G.; Eichler, C.H.; Hileman, A.R.; Mousseau, T.E. Jr.; Rackliffe, G.B.

    1980-06-05

    The program to study the effect of accidentally released carbon fibers on electrical power equipment consisted of determining the vulnerability of system outage rates to carbon fiber contamination, and performing tests to quantitize the contamination required to cause flashover of external insulation. Part One of this final report describes an assessment of the vulnerability of power systems to accidentally released fibers from a composite burn. The assessment describes the effect of carbon fibers on individual component failure rates and discusses the effect the change in component failure rates has on the power system reliability. Part Two describes in detail testing performed to determine the vulnerability of external insulation to carbon fiber contamination. Testing consisted of airborne contamination tests on distribution insulators, limited tests on suspension insulators which are commonly used for transmission class voltages, and various tests to quantify the influence of fiber length, voltage stress, etc. on flashover characteristics. The data obtained and analysis performed during this project show that the change of system reliability due to an accidental release from burned carbon fiber composite is negligible.

  3. Radioactivity released from burning gas lantern mantles.

    PubMed

    Luetzelschwab, J W; Googins, S W

    1984-04-01

    Gas lantern mantles contain thorium to produce incandescence when lantern fuel is burned on the mantle. Although only thorium is initially present on the mantle, the thorium daughters build up, some over a period of weeks and some over a period of years, and significant quantities of these daughters are present when the mantle is used. Some of these daughters are released when the lantern fuel is burned on the mantle. The amounts of radioactivity released during burning is studied by measuring the gamma radiation emitted by the daughters. Results of this study show that some of the radium (224Ra and 228Ra) and more than half the 212Pb and 212Bi is released during the first hour of a burn. The actual amounts release depend on the age of the mantle. PMID:6706595

  4. Deep Sludge Gas Release Event Analytical Evaluation

    SciTech Connect

    Sams, Terry L.

    2013-08-15

    Long Abstract. Full Text. The purpose of the Deep Sludge Gas Release Event Analytical Evaluation (DSGRE-AE) is to evaluate the postulated hypothesis that a hydrogen GRE may occur in Hanford tanks containing waste sludges at levels greater than previously experienced. There is a need to understand gas retention and release hazards in sludge beds which are 200 -300 inches deep. These sludge beds are deeper than historical Hanford sludge waste beds, and are created when waste is retrieved from older single-shell tanks (SST) and transferred to newer double-shell tanks (DST).Retrieval of waste from SSTs reduces the risk to the environment from leakage or potential leakage of waste into the ground from these tanks. However, the possibility of an energetic event (flammable gas accident) in the retrieval receiver DST is worse than slow leakage. Lines of inquiry, therefore, are (1) can sludge waste be stored safely in deep beds; (2) can gas release events (GRE) be prevented by periodically degassing the sludge (e.g., mixer pump); or (3) does the retrieval strategy need to be altered to limit sludge bed height by retrieving into additional DSTs? The scope of this effort is to provide expert advice on whether or not to move forward with the generation of deep beds of sludge through retrieval of C-Farm tanks. Evaluation of possible mitigation methods (e.g., using mixer pumps to release gas, retrieving into an additional DST) are being evaluated by a second team and are not discussed in this report. While available data and engineering judgment indicate that increased gas retention (retained gas fraction) in DST sludge at depths resulting from the completion of SST 241-C Tank Farm retrievals is not expected and, even if gas releases were to occur, they would be small and local, a positive USQ was declared (Occurrence Report EM-RP--WRPS-TANKFARM-2012-0014, "Potential Exists for a Large Spontaneous Gas Release Event in Deep Settled Waste Sludge"). The purpose of this technical

  5. Control of toxic gas release during the production of copper-indium-diselenide photovoltaic cells

    SciTech Connect

    Fowler, P.K.; Dobryn, D.G.; Lee, C.M.

    1986-03-01

    Toxic gas control systems will be needed to treat both routine and accidental H/sub 2/Se and H/sub 2/S emissions from manufacturing facilities producing CuInSe/sub 2/ photovoltaic cells. In this study, routine and accidental environmental control options were evaluated for a manufacturing plant with an annual production of cells capable of generating 10 MWp. A routine emissions treatment facility was designed which uses a venture scrubber, a packed-bed scrubber, and a carbon adsorption bed to reduce emissions to allowable limits. This facility incrementally increases the cost of manufacturing CuInSe/sub 2/ photovoltaic cells by 0.60 cents/Wp. Two alternative systems were designed to handle an accidental release: a packed-bed scrubber/carbon adsorption bed, and a containment scheme followed by carbon adsorption. The incremental costs of manufacturing for these release systems are 0.91 cents/Wp and 1.25 cents/Wp, respectively.

  6. Methane emissions and contaminant degradation rates at sites affected by accidental releases of denatured fuel-grade ethanol.

    PubMed

    Sihota, Natasha J; Mayer, K Ulrich; Toso, Mark A; Atwater, Joel F

    2013-08-01

    The recent increase in the use of denatured fuel-grade ethanol (DFE) has enhanced the probability of its environmental release. Due to the highly labile nature of ethanol (EtOH), it is expected to rapidly biodegrade, increasing the potential for inducing methanogenic conditions in the subsurface. As environmental releases of DFE can be expected to occur at the ground surface or in the vadose zone (e.g., due to surficial spills from rail lines or tanker trucks and leaking underground storage tanks), the potential for methane (CH4) generation at DFE spill sites requires evaluation. An assessment is needed because high CH4 generation rates may lead to CH4 fluxes towards the ground surface, which is of particular concern if spills are located close to human habitation-related to concerns of soil vapor intrusion (SVI). This work demonstrates, for the first time, the measurement of surficial gas release rates at large volume DFE spill sites. Two study sites, near Cambria and Balaton, in MN are investigated. Total carbon emissions at the ground surface (summing carbon dioxide (CO2) and CH4 emissions) are used to quantify depth-integrated DFE degradation rates. Results from both sites demonstrate that substantial CO2 and CH4 emissions do occur-even years after a spill. However, large total carbon fluxes, and CH4 emissions in particular, were restricted to a localized area within the DFE source zone. At the Balaton site, estimates of total DFE carbon losses in the source zone ranged between 5 and 174 μmol m(-2) s(-1), and CH4 effluxes ranged between non-detect and 9 μmol m(-2) s(-1). At the Cambria site estimates of total DFE carbon losses in the source zone ranged between 8 and 500 μmol m(-2) s(-1), and CH4 effluxes ranged between non-detect and 393 μmol m(-2) s(-1). Substantial CH4 accumulation, coupled with oxygen (O2) depletion, measured in samples collected from custom-designed gas collection chambers at the Cambria site suggests that the development of explosion

  7. Methane emissions and contaminant degradation rates at sites affected by accidental releases of denatured fuel-grade ethanol

    NASA Astrophysics Data System (ADS)

    Sihota, Natasha J.; Mayer, K. Ulrich; Toso, Mark A.; Atwater, Joel F.

    2013-08-01

    The recent increase in the use of denatured fuel-grade ethanol (DFE) has enhanced the probability of its environmental release. Due to the highly labile nature of ethanol (EtOH), it is expected to rapidly biodegrade, increasing the potential for inducing methanogenic conditions in the subsurface. As environmental releases of DFE can be expected to occur at the ground surface or in the vadose zone (e.g., due to surficial spills from rail lines or tanker trucks and leaking underground storage tanks), the potential for methane (CH4) generation at DFE spill sites requires evaluation. An assessment is needed because high CH4 generation rates may lead to CH4 fluxes towards the ground surface, which is of particular concern if spills are located close to human habitation—related to concerns of soil vapor intrusion (SVI). This work demonstrates, for the first time, the measurement of surficial gas release rates at large volume DFE spill sites. Two study sites, near Cambria and Balaton, in MN are investigated. Total carbon emissions at the ground surface (summing carbon dioxide (CO2) and CH4 emissions) are used to quantify depth-integrated DFE degradation rates. Results from both sites demonstrate that substantial CO2 and CH4 emissions do occur—even years after a spill. However, large total carbon fluxes, and CH4 emissions in particular, were restricted to a localized area within the DFE source zone. At the Balaton site, estimates of total DFE carbon losses in the source zone ranged between 5 and 174 μmol m- 2 s- 1, and CH4 effluxes ranged between non-detect and 9 μmol m- 2 s- 1. At the Cambria site estimates of total DFE carbon losses in the source zone ranged between 8 and 500 μmol m- 2 s- 1, and CH4 effluxes ranged between non-detect and 393 μmol m- 2 s- 1. Substantial CH4 accumulation, coupled with oxygen (O2) depletion, measured in samples collected from custom-designed gas collection chambers at the Cambria site suggests that the development of explosion or

  8. Accidental phosphine gas poisoning with fatal myocardial dysfunction in two families.

    PubMed

    Akhtar, Saleem; Rehman, Arshalooz; Bano, Surraya; Haque, Anwarul

    2015-05-01

    Aluminum phosphide is commonly used as a rodenticide and insecticide and is one of the most fatal poisons. The active ingredient is Phosphine gas which inhibits cytochrome oxidase and cellular oxygen utilization. The clinical symptoms are due to multiorgan involvement including cardiac toxicity which is the most common cause of mortality. Severity of clinical manifestations depends upon the amount of the gas to which a person is exposed. There is no specific antidote available. High index of suspicion and early aggressive treatment is the key to success. We report 2 cases of aluminum phosphide toxicity in 2 families due to incidental exposure after fumigation. PMID:26008669

  9. Calculation of External Gamma-Ray and Beta-Ray Doses from Accidental Atmospheric Releases of Radionuclides.

    1981-02-25

    SUBDOSA-II calculates submersion doses from an acute release of radionuclides to the atmosphere, as did SUBDOSA. Doses are calculated as a function of distance from release point, atmospheric stability, and wind speed for a specified radionuclide inventory. Contributions from both beta and gamma radiation are included as a function of tissue depth.

  10. MODELS SELECTED FOR CALCULATION OF DOSES, HEALTH EFFECTS AND ECONOMIC COSTS DUE TO ACCIDENTAL RADIONUCLIDE RELEASES FROM NUCLEAR POWER PLANTS

    SciTech Connect

    Strenge, D L; Baker, D A; Droppo, J G; McPherson, R B; Napier, B A; Nieves, L A; Soldat, J K; Watson, E C

    1980-05-01

    Models are described for use in site-specific environmental consequence analysis of nuclear reactor accidents of Classes 3 through 9. The models presented relate radioactivity released to resulting doses, health effects, and costs of remedial actions. Specific models are presented for the major exposure pathways of airborne releases, waterborne releases and direct irradiation from activity within the facility buildings, such as the containment. Time-dependent atmospheric dispersion parameters, crop production parameters and other variable parameters are used in the models. The environmental effects are analyzed for several accident start times during the year.

  11. Risk assessment, risk management and risk-based monitoring following a reported accidental release of poliovirus in Belgium, September to November 2014.

    PubMed

    Duizer, Erwin; Rutjes, Saskia; de Roda Husman, Ana Maria; Schijven, Jack

    2016-01-01

    On 6 September 2014, the accidental release of 10(13) infectious wild poliovirus type 3 (WPV3) particles by a vaccine production plant in Belgium was reported. WPV3 was released into the sewage system and discharged directly to a wastewater treatment plant (WWTP) and subsequently into rivers that flowed to the Western Scheldt and the North Sea. No poliovirus was detected in samples from the WWTP, surface waters, mussels or sewage from the Netherlands. Quantitative microbial risk assessment (QMRA) showed that the infection risks resulting from swimming in Belgium waters were above 50% for several days and that the infection risk by consuming shellfish harvested in the eastern part of the Western Scheldt warranted a shellfish cooking advice. We conclude that the reported release of WPV3 has neither resulted in detectable levels of poliovirus in any of the samples nor in poliovirus circulation in the Netherlands. This QMRA showed that relevant data on water flows were not readily available and that prior assumptions on dilution factors were overestimated. A QMRA should have been performed by all vaccine production facilities before starting up large-scale culture of WPV to be able to implement effective interventions when an accident happens. PMID:27020766

  12. Summary of gas release events detected by hydrogen monitoring

    SciTech Connect

    MCCAIN, D.J.

    1999-05-18

    This paper summarizes the results of monitoring tank headspace for flammable gas release events. In over 40 tank years of monitoring the largest detected release in a single-shell tank is 2.4 cubic meters of Hydrogen. In the double-shell tanks the largest release is 19.3 cubic meters except in SY-101 pre mixer pump installation condition.

  13. A fission gas release correlation for uranium nitride fuel pins

    NASA Technical Reports Server (NTRS)

    Weinstein, M. B.; Davison, H. W.

    1973-01-01

    A model was developed to predict fission gas releases from UN fuel pins clad with various materials. The model was correlated with total release data obtained by different experimentors, over a range of fuel temperatures primarily between 1250 and 1660 K, and fuel burnups up to 4.6 percent. In the model, fission gas is transported by diffusion mechanisms to the grain boundaries where the volume grows and eventually interconnects with the outside surface of the fuel. The within grain diffusion coefficients are found from fission gas release rate data obtained using a sweep gas facility.

  14. User's manual for LPGS: a computer program for calculating radiation exposure resulting from accidental radioactive releases to the hydrosphere

    SciTech Connect

    White, J.E.; Eckerman, K.F.

    1982-11-01

    The LPGS computer program was developed to calculate the radiological impacts resulting from radioactive releases to the hydrosphere. The hydrosphere is represented by the following types of water bodies: estuary, small river, well, lake, and one-dimensional (1-D) river. The program is principally designed to calculate radiation dose (individual and population) to body organs as a function of time for the various exposure pathways. The radiological consequences to the aquatic biota is estimated. Several simplified radionuclide transport models are employed with built-in formulations to describe the release rate of the radio-nuclides. Optionally, a tabulated user-supplied release model can be input. Printer plots of dose versus time for the various exposure pathways are provided.

  15. Modeling of Fission Gas Release in UO2

    SciTech Connect

    MH Krohn

    2006-01-23

    A two-stage gas release model was examined to determine if it could provide a physically realistic and accurate model for fission gas release under Prometheus conditions. The single-stage Booth model [1], which is often used to calculate fission gas release, is considered to be oversimplified and not representative of the mechanisms that occur during fission gas release. Two-stage gas release models require saturation at the grain boundaries before gas is release, leading to a time delay in release of gases generated in the fuel. Two versions of a two-stage model developed by Forsberg and Massih [2] were implemented using Mathcad [3]. The original Forsbers and Massih model [2] and a modified version of the Forsberg and Massih model that is used in a commercially available fuel performance code (FRAPCON-3) [4] were examined. After an examination of these models, it is apparent that without further development and validation neither of these models should be used to calculate fission gas release under Prometheus-type conditions. There is too much uncertainty in the input parameters used in the models. In addition. the data used to tune the modified Forsberg and Massih model (FRAPCON-3) was collected under commercial reactor conditions, which will have higher fission rates relative to Prometheus conditions [4].

  16. Behavior of accidentally released radiocesium in soil-water environment: Looking at Fukushima from a Chernobyl perspective.

    PubMed

    Konoplev, A; Golosov, V; Laptev, G; Nanba, K; Onda, Y; Takase, T; Wakiyama, Y; Yoshimura, K

    2016-01-01

    Quantitative characteristics of dissolved and particulate radiocesium wash-off from contaminated watersheds after the FDNPP accident are calculated based on published monitoring data. Comparative analysis is provided for radiocesium wash-off parameters and distribution coefficients, Kd, between suspended matter and water in rivers and surface runoff on Fukushima and Chernobyl contaminated areas for the first years after the accidents. It was found that radiocesium distribution coefficient in Fukushima rivers is essentially higher (1-2 orders of magnitude) than corresponding values for rivers and surface runoff within the Chernobyl zone. This can be associated with two factors: first, the high fraction of clays in the predominant soils and sediments of the Fukushima area and accordingly a higher value of the radiocesium Interception Potential, RIP, in general, and secondly the presence of water insoluble glassy particles containing radiocesium in the accidental fallout at Fukushima. It was found also that normalized dissolved wash-off coefficients for Fukushima catchments are 1-2 orders of magnitude lower than corresponding values for the Chernobyl zone. Normalized particulate wash-off coefficients are comparable for Fukushima and Chernobyl. Results of the investigation of radiocesium's ((134)Cs and (137)Cs) vertical distribution in soils of the close-in area of the Fukushima Dai-ichi NPP - Okuma town and floodplain of the Niida river are presented. The radiocesium migration in undisturbed forest and grassland soils at Fukushima contaminated area has been shown to be faster as compared to the Chernobyl 30-km zone during the first three years after the accidents. This may be associated with higher annual precipitation (by about 2.5 times) in Fukushima as compared to the Chernobyl zone, as well as the differences in the soil characteristics and temperature regime throughout a year. Investigation and analysis of Fukushima's radiocesium distribution in soils of Niida

  17. DISPERSION OF DENSE GAS RELEASES IN A WIND TUNNEL

    EPA Science Inventory

    The paper documents two dense gas projects undertaken at the US EPA Fluid Modeling Facility. The study investigated the basic nature of the transport and dispersion of a dense gas plume in a simulated neutral atmospheric boundary layer. The two dense gas releases were CO2 and SF6...

  18. Fission-gas-release rates from irradiated uranium nitride specimens

    NASA Technical Reports Server (NTRS)

    Weinstein, M. B.; Kirchgessner, T. A.; Tambling, T. N.

    1973-01-01

    Fission-gas-release rates from two 93 percent dense UN specimens were measured using a sweep gas facility. Specimen burnup rates averaged .0045 and .0032 percent/hr, and the specimen temperatures ranged from 425 to 1323 K and from 552 to 1502 K, respectively. Burnups up to 7.8 percent were achieved. Fission-gas-release rates first decreased then increased with burnup. Extensive interconnected intergranular porosity formed in the specimen operated at over 1500 K. Release rate variation with both burnup and temperature agreed with previous irradiation test results.

  19. Medical planning for toxic releases into the community: the example of chlorine gas.

    PubMed Central

    Baxter, P J; Davies, P C; Murray, V

    1989-01-01

    Emergency planning for a major accidental release of chlorine gas from industrial installations into the community is outlined for emergency services and hospitals. Realistic planning has been made possible with the advent of computer models for gas dispersion which may be used to estimate the numbers of deaths and casualties, according to their severity. For most purposes sufficient accuracy may be obtained by using a small number of computer analyses for the most serious reasonably foreseeable events under typical day and night weather conditions, and allowing for the emergency response to be scaled up or down according to the size of an actual release. In highly populated areas triage should be preplanned to deal with a large number of victims; field stations will be needed for the treatment and observation of minor casualties. The management and treatment of casualties is summarised. The best protection against a gas cloud is afforded by buildings whose windows, doors, and ventilation systems have been closed. Hospitals in the vicinity of an installation should draw up plans to protect patients and staff. Coordination in a disaster will require toxicological and epidemiological expertise and hospital plans should allow for this. PMID:2713283

  20. A computer code to estimate accidental fire and radioactive airborne releases in nuclear fuel cycle facilities: User's manual for FIRIN

    SciTech Connect

    Chan, M.K.; Ballinger, M.Y.; Owczarski, P.C.

    1989-02-01

    This manual describes the technical bases and use of the computer code FIRIN. This code was developed to estimate the source term release of smoke and radioactive particles from potential fires in nuclear fuel cycle facilities. FIRIN is a product of a broader study, Fuel Cycle Accident Analysis, which Pacific Northwest Laboratory conducted for the US Nuclear Regulatory Commission. The technical bases of FIRIN consist of a nonradioactive fire source term model, compartment effects modeling, and radioactive source term models. These three elements interact with each other in the code affecting the course of the fire. This report also serves as a complete FIRIN user's manual. Included are the FIRIN code description with methods/algorithms of calculation and subroutines, code operating instructions with input requirements, and output descriptions. 40 refs., 5 figs., 31 tabs.

  1. Fission gas release restrictor for breached fuel rod

    DOEpatents

    Kadambi, N. Prasad; Tilbrook, Roger W.; Spencer, Daniel R.; Schwallie, Ambrose L.

    1986-01-01

    In the event of a breach in the cladding of a rod in an operating liquid metal fast breeder reactor, the rapid release of high-pressure gas from the fission gas plenum may result in a gas blanketing of the breached rod and rods adjacent thereto which impairs the heat transfer to the liquid metal coolant. In order to control the release rate of fission gas in the event of a breached rod, the substantial portion of the conventional fission gas plenum is formed as a gas bottle means which includes a gas pervious means in a small portion thereof. During normal reactor operation, as the fission gas pressure gradually increases, the gas pressure interiorly of and exteriorly of the gas bottle means equalizes. In the event of a breach in the cladding, the gas pervious means in the gas bottle means constitutes a sufficient restriction to the rapid flow of gas therethrough that under maximum design pressure differential conditions, the fission gas flow through the breach will not significantly reduce the heat transfer from the affected rod and adjacent rods to the liquid metal heat transfer fluid flowing therebetween.

  2. Analysis of fission gas release kinetics by on-line mass spectrometry

    SciTech Connect

    Zerega, Y.; Reynard-Carette, C.; Parrat, D.; Carette, M.; Brkic, B.; Lyoussi, A.; Bignan, G.; Janulyte, A.; Andre, J.; Pontillon, Y.; Ducros, G.; Taylor, S.

    2011-07-01

    The release of fission gas (Xe and Kr) and helium out of nuclear fuel materials in normal operation of a nuclear power reactor can constitute a strong limitation of the fuel lifetime. Moreover, radioactive isotopes of Xe and Kr contribute significantly to the global radiological source term released in the primary coolant circuit in case of accidental situations accompanied by fuel rod loss of integrity. As a consequence, fission gas release investigation is of prime importance for the nuclear fuel cycle economy, and is the driven force of numerous R and D programs. In this domain, for solving current fuel behavior understanding issues, preparing the development of new fuels (e.g. for Gen IV power systems) and for improving the modeling prediction capability, there is a marked need for innovations in the instrumentation field, mainly for: . Quantification of very low fission gas concentrations, released from fuel sample and routed in sweeping lines. Monitoring of quick gas release variations by quantification of elementary release during a short period of time. Detection of a large range of atomic masses (e.g. H{sub 2}, HT, He, CO, CO{sub 2}, Ne, Ar, Kr, Xe), together with a performing separation of isotopes for Xe and Kr elements. Coupling measurement of stable and radioactive gas isotopes, by using in parallel mass spectrometry and gamma spectrometry techniques. To fulfill these challenging needs, a common strategy for analysis equipment implementation has been set up thanks to a recently launched collaboration between the CEA and the Univ. of Provence, with the technological support of the Liverpool Univ.. It aims at developing a chronological series of mass spectrometer devices based upon mass filter and 2D/3D ion traps with Fourier transform operating mode and having increasing levels of performances to match the previous challenges for out-of pile and in-pile experiments. The final objective is to install a high performance online mass spectrometer coupled to

  3. Monitoring perfluorinated surfactants in biota and surface water samples following an accidental release of fire-fighting foam into Etobicoke Creek.

    PubMed

    Moody, Cheryl A; Martin, Jonathan W; Kwan, Wai Chi; Muir, Derek C G; Mabury, Scott A

    2002-02-15

    Perfluorinated surfactants have emerged as priority environmental contaminants due to recent reports of their detection in environmental and biological matrices as well as concerns regarding their persistence and toxicity. In June 2000, 22000 L of fire retardant foam containing perfluorinated surfactants was accidentally released at L. B. Pearson International Airport, Toronto, ON, and subsequently entered into Etobicoke Creek, a tributary to Lake Ontario. A suite of analytical tools that include liquid chromatography/tandem mass spectrometry (LC/MS/MS) and 19F NMR were employed to characterize fish (common shiner, Notropus cornutus) and surface water samples collected following the discharge of the perfluorinated material. Total perfluoroalkanesulfonate (4, 6, and 8 carbons) concentrations in fish liver samples ranged from 2.00 to 72.9 microg/g, and total perfluorocarboxylate (5-14 carbons) concentrations ranged from 0.07 to 1.02 microg/g. In addition to fish samples, total perfluoroalkanesulfonate (6 and 8 carbons) concentrations were detected in creek water samples by LC/MS/MS over a 153 day sampling period with concentrations ranging from <0.017 to 2260 microg/L; perfluorooctanoate concentrations (<0.009-11.3 microg/L) were lower than those observed for the perfluoroalkane-sulfonates. By 19F NMR, the total perfluorinated surfactant concentrations in surface water samples ranged from < 10 to 17000 microg/L. A bioaccumulation factor range of 6300-125000 was calculated for perfluorooctanesulfonate, based on concentrations in fish liver and surface water. The residence time of perfluorooctanesulfonate in Etobicoke Creek as well as the high bioaccumulation in fish liver suggests that perfluorinated surfactants will persist and bioaccumulate following release into the aquatic environment. PMID:11883418

  4. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 6. Summary

    SciTech Connect

    Peterson, S

    2007-09-05

    Throughout fifty-three years of operations, an estimated 792,000 Ci (29,300 TBq) of tritium have been released to the atmosphere at the Livermore site of Lawrence Livermore National Laboratory (LLNL); about 75% was tritium gas (HT) primarily from the accidental releases of 1965 and 1970. Routine emissions contributed slightly more than 100,000 Ci (3,700 TBq) HT and about 75,000 Ci (2,800 TBq) tritiated water vapor (HTO) to the total. A Tritium Dose Reconstruction was undertaken to estimate both the annual doses to the public for each year of LLNL operations and the doses from the few accidental releases. Some of the dose calculations were new, and the others could be compared with those calculated by LLNL. Annual doses (means and 95% confidence intervals) to the potentially most exposed member of the public were calculated for all years using the same model and the same assumptions. Predicted tritium concentrations in air were compared with observed mean annual concentrations at one location from 1973 onwards. Doses predicted from annual emissions were compared with those reported in the past by LLNL. The highest annual mean dose predicted from routine emissions was 34 {micro}Sv (3.4 mrem) in 1957; its upper confidence limit, based on very conservative assumptions about the speciation of the release, was 370 {micro}Sv (37 mrem). The upper confidence limits for most annual doses were well below the current regulatory limit of 100 {micro}Sv (10 mrem) for dose to the public from release to the atmosphere; the few doses that exceeded this were well below the regulatory limits of the time. Lacking the hourly meteorological data needed to calculate doses from historical accidental releases, ingestion/inhalation dose ratios were derived from a time-dependent accident consequence model that accounts for the complex behavior of tritium in the environment. Ratios were modified to account for only those foods growing at the time of the releases. The highest dose from an

  5. ACCIDENTAL RELEASE INFORMATION PROGRAM (ARIP)

    EPA Science Inventory

    The Environmental Protection Agencys (EPAs) Chemical Emergency Preparedness and Prevention Office(CEPPO) leads the effort to deal with chemical accidents. The Agency began its chemical accident prevention program in 1986. To identify the steps that could be taken by industrial fa...

  6. Lunar activity from recent gas release.

    PubMed

    Schultz, Peter H; Staid, Matthew I; Pieters, Carlé M

    2006-11-01

    Samples of material returned from the Moon have established that widespread lunar volcanism ceased about 3.2 Gyr ago. Crater statistics and degradation models indicate that last-gasp eruptions of thin basalt flows continued until less than 1.0 Gyr ago, but the Moon is now considered to be unaffected by internal processes today, other than weak tidally driven moonquakes and young fault systems. It is therefore widely assumed that only impact craters have reshaped the lunar landscape over the past billion years. Here we report that patches of the lunar regolith in the Ina structure were recently removed. The preservation state of relief, the number of superimposed small craters, and the 'freshness' (spectral maturity) of the regolith together indicate that features within this structure must be as young as 10 Myr, and perhaps are still forming today. We propose that these features result from recent, episodic out-gassing from deep within the Moon. Such out-gassing probably contributed to the radiogenic gases detected during past lunar missions. Future monitoring (including Earth-based observations) should reveal the composition of the gas, yielding important clues to volatiles archived at great depth over the past 4-4.5 Gyr. PMID:17093445

  7. Determination of VX-G analogue in red blood cells via gas chromatography-tandem mass spectrometry following an accidental exposure to VX.

    PubMed

    McGuire, Jeffrey M; Taylor, James T; Byers, Christopher E; Jakubowski, Edward M; Thomson, Sandra M

    2008-01-01

    A sensitive method for determining exposure to the chemical warfare agent VX is described in which the biomarker ethyl methylphosphonofluoridate (VX-G) is measured in red blood cells (RBCs) following treatment with fluoride ion using isotope-dilution gas chromatography-tandem mass spectrometry. The analyte was isolated via solid-phase extraction and detected using ammonia chemical ionization in the multiple reaction monitoring mode. A good linear relationship was obtained in the quantitative concentration range of 4 ng/mL to 1000 ng/mL with an absolute detection limit of < 1 pg on column. The method has been applied to the analysis of RBCs from a laboratory worker accidentally exposed to VX vapor. Detection and quantitation of VX-G were possible in samples taken as late as 27 days following exposure. PMID:18269797

  8. Accidental Art

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Figure 1 (Click on image for larger view)

    This image, acquired by the Mars Exploration Rover Spirit's panoramic camera on the 53rd martian day, or sol, of the rover's mission, struck science and engineering teams as not only scientifically interesting but remarkably beautiful. The large, shadowed rock in the foreground is nicknamed 'Sandia' for a mountain range in New Mexico. An imposing rock, 'Sandia' is about 33 centimeters high (1 foot) and about 1.7 meters (5.5 feet) long.

    Figure 1 above is a lightened version of the more artistic image above.

    The combination of the rover's high-resolution cameras with software tools used by scientists allows the minute details on martian targets to be visualized. When lightened, this image reveals much about the pictured rocks, which the science team believes are ejected material, or ejecta, from the nearby crater called 'Bonneville.' Scientists believe 'Sandia' is a basaltic rock that landed on its side after being ejected from the crater. The vertical lines on the side of the rock facing the camera are known by geologists as 'flow banding' and typically run horizontally, indicating that 'Sandia' is on its side. What look like small holes on the two visible sides of the rock are called vesicles; they were probably once gas bubbles within the lava.

    The lighting not only makes for an artistic image, it helps scientists get a virtual three-dimensional feel for target rocks. Observations taken at different times of day, as shadows move and surface texture details on target rocks are revealed, are entered into modeling software that turns a two-dimensional image into a three-dimensional research tool.

    Many smaller rocks can be seen in the background of the image. Some rocks are completely exposed, while others are only peeking out of the surface. Scientists believe that two processes might be at work here: accretion, which occurs when winds deposit material that

  9. Gas release from the LUSI eruption site: large scale estimates.

    NASA Astrophysics Data System (ADS)

    Sciarra, A.; Mazzini, A.; Etiope, G.; Husein, A.; Hadi, S.

    2015-12-01

    The spectacular Indonesian Lusi mud eruption started in May 2006 following to a 6.3 M earthquake striking the island of Java. Previous studies investigated the mechanisms of reactivation of the Watukosek fault system that crosses Lusi locality and continues to the NE of Java. Results show that the quake triggered lateral movement of this strike-slip system resulting in several aligned eruptions sites including Lusi. Geochemical studies of the erupted fluids reveal a mantle signature and point to a connection with the neighboring Arjuno-Welirang volcanic complex indicating that Lusi is a sedimentary hosted geothermal system. In order to better understand 1) the geometry of the Lusi subsurface plumbing system, 2) to estimate the type and the amount of gas released, and 3) how tectonic structures may control this activity, we conducted a comprehensive survey around the Lusi crater. We sampled more than 60 seepage sites to analyze the composition of the gas released and conducted a flux measurements survey of over 350 stations (CO2 and CH4). In addition we completed three CO2, CH4, radon profiles (120 points) perpendicular to the NE-SW oriented Watukosek strike-slip fault system and complemented that with geoelectric surveys. Results show that the whole area is characterized by diffused gas release through seeps, fractures, microfractures and soil degassing. Overall the highest gas flux were recorded at stations crossing the fractured zones that coincide with the position of the Watukosek fault system. The fractures release mainly CO2 (with peaks up to 400 g/m2day) and display higher temperatures (up to 41°C). This main shear zone is populated by numerous seeps that expel mostly CH4. Flux measurements in the seeping pools reveal that φCO2 is an order of magnitude higher than that measured in the fractures, and two orders of magnitude for φCH4. Radon measurements vary from 30 and 90 Bq/m3 on the edges of the study area to 6000 Bq/m3in the proximity of the faulted

  10. Expansion of a Quantum Gas Released from an Optical Lattice

    SciTech Connect

    Gerbier, F.; Trotzky, S.; Schnorrberger, U.; Thompson, J. D.; Bloch, I.; Foelling, S.; Widera, A.; Pollet, L.; Troyer, M.; Capogrosso-Sansone, B.; Prokof'ev, N. V.; Svistunov, B. V.

    2008-10-10

    We analyze the interference pattern produced by ultracold atoms released from an optical lattice, commonly interpreted as the momentum distributions of the trapped quantum gas. We show that for finite times of flight the resulting density distribution can, however, be significantly altered, similar to a near-field diffraction regime in optics. We illustrate our findings with a simple model and realistic quantum Monte Carlo simulations for bosonic atoms and compare the latter to experiments.

  11. Expansion of a Quantum Gas Released from an Optical Lattice

    NASA Astrophysics Data System (ADS)

    Gerbier, F.; Trotzky, S.; Fölling, S.; Schnorrberger, U.; Thompson, J. D.; Widera, A.; Bloch, I.; Pollet, L.; Troyer, M.; Capogrosso-Sansone, B.; Prokof'Ev, N. V.; Svistunov, B. V.

    2008-10-01

    We analyze the interference pattern produced by ultracold atoms released from an optical lattice, commonly interpreted as the momentum distributions of the trapped quantum gas. We show that for finite times of flight the resulting density distribution can, however, be significantly altered, similar to a near-field diffraction regime in optics. We illustrate our findings with a simple model and realistic quantum Monte Carlo simulations for bosonic atoms and compare the latter to experiments.

  12. Proposed gas release experiment on the argos satellite. Interim report

    SciTech Connect

    Lai, S.T.; Murad, E.; Pike, C.P.

    1992-01-29

    We propose to release xenon and carbon dioxide gases from nozzles on the Advanced Research and Global Observation Satellite (ARGOS) satellite orbiting with a velocity of about 7.4 km/s at an altitude of about 800 km. The releases will be conducted mostly in darkness over the Maui telescope site. The vector sum of the satellite and gas velocities will exceed the velocity requirement for the critical ionization velocity (CIV) process of xenon. It is feasible that the xenon gas will achieve critical velocity ionization. Associative ionization and collisional stripping will not occur for the xenon gas and there is no photo-ionization in darkness; ionization processes competing with CIV are absent. Neutral density, ambient magnetic field, and seed ionization effects on the xenon gas CIV will be discussed. Unlike xenon, carbon dioxide will not undergo CIV because of its higher velocity requirement. However, it is feasible that carbon dioxide colliding with the atmospheric species will form excited CO and OH molecules, which will radiate subsequently. Optical, IR, and UV observations on the satellite and at Maui will provide diagnostic measurements for the experiment.

  13. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  14. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  15. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  16. Gas release driven dynamics in research reactors piping

    SciTech Connect

    Kolev, Nikolay Ivanov; Roloff-Bock, Iris; Schlicht, Gerhard

    2006-07-01

    Analysis of the physical and chemical processes of radiolysis gas production, air absorption, diffusion controlled gas release and transport in the coolant cleaning system of the research reactor FRM II, which is now being in routine power operation in Munich, Germany, lead to the following conclusions: 1) The steady state pressure distribution in the siphon pipe allows that the horizontal part of the siphon pipe is filled with air. The air is isolated by about 1 m water column from the main pipe of the coolant cleaning system (CCS). This is a stable steady state. It has two positive impacts on the normal operation of the CCS: (a) there is effectively no bypass flow; (b) The air can not be transported through the pipe and therefore no deterioration of the pump performance is expected from the function of the siphon pipe. 2) Radiolysis gas production for coolant, that initially does not contain dissolved air, does not lead to any problem for the system. The gases are dissolved in the coolant at 2.2 bar and are not released for pressures reduction to about 1 bar, which is the minimum pressure in the CCS. 3) Assuming hypothetically a radiolysis gas production for coolant, which initially does contain dissolved air close to its saturation, leads to gas slug formation and its transport up to the pump. This could reduce the pump head and could lead to distortion of the normal operation. Systematic measurement of the hydrogen in the primary system at 100% power indicated, that this state is not realized in the system. The observed H{sub 2} concentration was between 0.016 e-6 and 0.380 e-6 which is of no concern at all. (authors)

  17. A multiple lines of evidence approach for the ecological risk assessment of an accidental bitumen release from a steam assisted gravity drainage (SAGD) well in the Athabasca oil sands region.

    PubMed

    Berger, Robert G; Aslund, Melissa Whitfield; Sanders, Greg; Charlebois, Michael; Knopper, Loren D; Bresee, Karl E

    2016-01-15

    To assess the ecological impacts of two independent accidental bitumen releases from two steam assisted gravity drainage (SAGD) wells in the Athabasca oil sands region, a multiple lines of evidence (LOE) approach was developed. Following the release in 2010, action was taken to minimize environmental impact, including the selective removal of the most highly impacted vegetation and the use of oil socks to minimize possible runoff. An ecological risk assessment (ERA) was then conducted based on reported concentrations of bitumen related contaminants in soil, vegetation, and water. Results of biological assessments conducted at the site were also included in the risk characterization. Overall, the conclusion of the ERA was that the likelihood of long-term adverse health effects to ecological receptors in the area was negligible. To provide evidence for this conclusion, a small mammal sampling plan targeting Southern red-back voles (Myodes gapperi) was carried out at two sites and two relevant reference areas. Voles were readily collected at all locations and no statistically significant differences in morphometric measurements (i.e., body mass, length, foot length, and adjusted liver weight) were found between animals collected from impact zones of varying levels of coverage. Additionally, no trends corresponding with bitumen coverage were observed with respect to metal body burden in voles for metals that were previously identified in the source bitumen. Hepatic ethoxyresorufin-O-deethylase (EROD) activity was statistically significantly elevated in voles collected from the high impact zones of sites compared to those collected from the reference areas, a finding that is indicative of continued exposure to contaminants. However, this increase in EROD was not correlated with any observable adverse population-wide biological outcomes. Therefore the biological sampling program supported the conclusion of the initial ERA and supported the hypothesis of no significant

  18. An efficient model for the analysis of fission gas release

    NASA Astrophysics Data System (ADS)

    Bernard, L. C.; Jacoud, J. L.; Vesco, P.

    2002-04-01

    This paper presents the fission gas release (FGR) model that has been developed at Framatome ANP and incorporated into its fuel rod performance code COPERNIC in order to accurately predict FGR into pressurized water reactor fuel rods under normal and off-normal operating conditions including UO 2, gadolinia and MOX fuels. The model is analytical, thus enabling fast and robust fuel rod calculations, a must within an industrial framework where safety evaluations may require the analyses of a full core and of a very large number of transients. Although the model is simple, it includes the most important FGR features: athermal, thermal, steady-state, and transient regimes, burst effect, rim formation, and MOX-type microstructure. The validation of the model covers 400 irradiated rods that include high burnups, high powers, short to long transients, and shows the quality of the prediction of the model in all types of conditions. As temperature is a key parameter that affects FGR, the COPERNIC thermal model is briefly described and its impact on fission gas released uncertainty is discussed.

  19. Transport of dissolved gas and its ecological impact after a gas release from deepwater.

    PubMed

    Wimalaratne, Malinda R; Yapa, Poojitha D; Nakata, Kisaburo; Premathilake, Lakshitha T

    2015-11-15

    Previous models on simulating gas releases in deepwater were not focused on the dissolved component and its impact on water quality. This paper presents a new model developed for simulating the transport/spread of dissolved methane from an underwater release and its impact on dissolved oxygen in ambient water. Methane dissolves into ambient water from gas phase, direct from hydrate phase, and from dissociating hydrates formed earlier. Dissolved methane affects the dissolved oxygen levels in ambient water due to microbial interaction and possible direct absorption of oxygen into methane bubbles. We use new model simulations of Deepspill field experiments to compare with instantaneous profiles which were unpublished until now. The comparisons are very good with a short time lag, but are within the acceptable discrepancy for models for emergency response and contingency planning. Scenario simulations show the effect on dissolved oxygen due to different methane release situations. PMID:26364205

  20. Mathematical model for predicting the probability of acute mortality in a human population exposed to accidentally released airborne radionuclides. Final report for Phase I

    SciTech Connect

    Filipy, R.E.; Borst, F.J.; Cross, F.T.; Park, J.F.; Moss, O.R.; Roswell, R.L.; Stevens, D.L.

    1980-05-01

    A mathematical model was constructed for the purpose of predicting the fraction of human population which would die within 1 year of an accidental exposure to airborne radionuclides. The model is based on data from laboratory experiments with rats, dogs and baboons, and from human epidemiological data. Doses from external, whole-body irradiation and from inhaled, alpha- and beta-emitting radionuclides are calculated for several organs. The probabilities of death from radiation pneumonitis and from bone marrow irradiation are predicted from doses accumulated within 30 days of exposure to the radioactive aerosol. The model is compared with existing similar models under hypothetical exposure conditions. Suggestions for further experiments with inhaled radionuclides are included. 25 refs., 16 figs., 13 tabs.

  1. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 1. CONTROL OF ACCIDENTAL RELEASES OF HYDROGEN FLUORIDE (SCAQMD) (SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT)

    EPA Science Inventory

    The manual summarizes technical information that will assist in identifying and controlling hydrogen fluoride release hazards specific to the South Coast Air Quality Management District (SCAQMD) of southern California. The SCAQMD has considered a strategy for reducing the risk of...

  2. Comments on 'Gas release from comets' and related trapped-gas experiments

    NASA Technical Reports Server (NTRS)

    Hudson, R. L.; Donn, B.

    1992-01-01

    The numerous variables influencing trapped-gas experiment results based on cometary ice analogs are presently discussed in view of the Notesco et al. (1991) data on Kr-trapping and release by H2O ice. Attention is drawn to the questionable tennability of a linear relation proposed between the thickness of the ice and the gas retained beyond the amorphous-to-cubic phase change of H2O. Exacting care is required in the application of laboratory results to cometary phenomena, rendering definitive conclusions extremely elusive.

  3. Fission gas release from oxide fuels at high burnups (AWBA development program)

    SciTech Connect

    Dollins, C.C.

    1981-02-01

    The steady state gas release, swelling and densification model previously developed for oxide fuels has been modified to accommodate the slow transients in temperature, temperature gradient, fission rate and pressure that are encountered in normal reactor operation. The gas release predictions made by the model were then compared to gas release data on LMFBR-EBRII fuels obtained by Dutt and Baker and reported by Meyer, Beyer, and Voglewede. Good agreement between the model and the data was found. A comparison between the model and three other sets of gas release data is also shown, again with good agreement.

  4. Effects of Globally Waste Disturbing Activities on Gas Generation, Retention, and Release in Hanford Waste Tanks

    SciTech Connect

    Stewart, Charles W.; Fountain, Matthew S.; Huckaby, James L.; Mahoney, Lenna A.; Meyer, Perry A.; Wells, Beric E.

    2005-08-02

    Various operations are authorized in Hanford single- and double-shell tanks that disturb all or a large fraction of the waste. These globally waste-disturbing activities have the potential to release a large fraction of the retained flammable gas and to affect future gas generation, retention, and release behavior. This report presents analyses of the expected flammable gas release mechanisms and the potential release rates and volumes resulting from these activities. The background of the flammable gas safety issue at Hanford is summarized, as is the current understanding of gas generation, retention, and release phenomena. Considerations for gas monitoring and assessment of the potential for changes in tank classification and steady-state flammability are given.

  5. Gas retention and release behavior in Hanford double-shell waste tanks

    SciTech Connect

    Meyer, P.A.; Brewster, M.E.; Bryan, S.A.

    1997-05-01

    This report describes the current understanding of flammable gas retention and release in Hanford double-shell waste tanks AN-103, AN-104, AN-105, AW-101, SY-101, and SY-103. This knowledge is based on analyses, experimental results, and observations of tank behavior. The applicable data available from the void fraction instrument, retained gas sampler, ball rheometer, tank characterization, and field monitoring are summarized. Retained gas volumes and void fractions are updated with these new data. Using the retained gas compositions from the retained gas sampler, peak dome pressures during a gas burn are calculated as a function of the fraction of retained gas hypothetically released instantaneously into the tank head space. Models and criteria are given for gas generation, initiation of buoyant displacement, and resulting gas release; and predictions are compared with observed tank behavior.

  6. Composite accidental axions

    NASA Astrophysics Data System (ADS)

    Redi, Michele; Sato, Ryosuke

    2016-05-01

    We present several models where the QCD axion arises accidentally. Confining gauge theories can generate axion candidates whose properties are uniquely determined by the quantum numbers of the new fermions under the Standard Model. The Peccei-Quinn symmetry can emerge accidentally if the gauge theory is chiral. We generalise previous constructions in a unified framework. In some cases these models can be understood as the deconstruction of 5-dimensional gauge theories where the Peccei-Quinn symmetry is protected by locality but more general constructions are possible.

  7. Code System for Real-Time Prediction of Radiation Dose to the Public Due to an Accidental Release from a Nuclear Power Plant.

    1987-01-20

    Version 00 The suite of computer codes, SPEEDI, predicts the dose to the public from a plume released from a nuclear power plant. The main codes comprising SPEEDI are: WIND04, PRWDA, and CIDE. WIND04 calculates three-dimensional mass-conservative windfields. PRWDA calculates concentration distributions, and CIDE estimates the external and internal doses. These models can take into account the spatial and temporal variation of wind, variable topography, deposition and variable source intensity for use in real-time assessment.more » We recommend that you also review the emergency response supporting system CCC-661/ EXPRESS documentation.« less

  8. Gas retention and release behavior in Hanford single-shell waste tanks

    SciTech Connect

    Stewart, C.W.; Brewster, M.E.; Gauglitz, P.A.; Mahoney, L.A.; Meyer, P.A.; Recknagle, K.P.; Reid, H.C.

    1996-12-01

    This report describes the current understanding of flammable gas retention and release in Hanford single-shell waste tanks based on theory, experimental results, and observations of tank behavior. The single-shell tanks likely to pose a flammable gas hazard are listed and described, and photographs of core extrusions and the waste surface are included. The credible mechanisms for significant flammable gas releases are described, and release volumes and rates are quantified as much as possible. The only mechanism demonstrably capable of producing large ({approximately}100 m{sup 3}) spontaneous gas releases is the buoyant displacement, which occurs only in tanks with a relatively deep layer of supernatant liquid. Only the double-shell tanks currently satisfy this condition. All release mechanisms believed plausible in single-shell tanks have been investigated, and none have the potential for large spontaneous gas releases. Only small spontaneous gas releases of several cubic meters are likely by these mechanisms. The reasons several other postulated gas release mechanisms are implausible or incredible are also given.

  9. Accidental sexual strangulation.

    PubMed

    Michalodimitrakis, M; Frangoulis, M; Koutselinis, A

    1986-03-01

    Accidental death by manual strangulation among homosexuals during the act of sodomy is an uncommon event. In our recent case, the pattern of injuries indicates that strangulation resulted from the forearm application on the neck in a manner better known as "choke holding." PMID:3728426

  10. Dynamics of Crust Dissolution and Gas Release in Tank 241-SY-101

    SciTech Connect

    Rassat, Scot D.; Stewart, Charles W.; Wells, Beric E.; Kuhn, William L.; Antoniak, Zenen I.; Cuta, Judith M.; Recknagle, Kurtis P.; Terrones, Guillermo; Viswanathan, Vilayanur V.; Sukamto, Johanes H.; Mendoza, Donaldo P.

    2000-01-24

    Due primarily to an increase in floating crust thickness, the waste level in Tank 241-SY-101 has grown appreciably and the flammable gas volume stored in the crust has become a potential hazard. To remediate gas retention in the crust and the potential for buoyant displacement gas releases from the nonconvective layer at the bottom of the tank, SY-101 will be diluted to dissolve a large fraction of the solids that allow the waste to retain gas. The plan is to transfer some waste out and back-dilute with water in several steps. In this work, mechanisms and rates of waste solids dissolution and gas releases are evaluated theoretically and experimentally. Particular emphasis is given to crust dissolution processes and associated gas releases, although dissolution and gas release from the mixed-slurry and nonconvective layers are also considered. The release of hydrogen gas to the tank domespace is modeled for a number of scenarios. Under the tank conditions expected at the time of back-dilution, no plausible continuous or sudden gas release scenarios resulting in flammable hydrogen concentrations were identified.

  11. Capture and release of acid-gasses with acid-gas binding organic compounds

    DOEpatents

    Heldebrant, David J; Yonker, Clement R; Koech, Phillip K

    2015-03-17

    A system and method for acid-gas capture wherein organic acid-gas capture materials form hetero-atom analogs of alkyl-carbonate when contacted with an acid gas. These organic-acid gas capture materials include combinations of a weak acid and a base, or zwitterionic liquids. This invention allows for reversible acid-gas binding to these organic binding materials thus allowing for the capture and release of one or more acid gases. These acid-gas binding organic compounds can be regenerated to release the captured acid gasses and enable these organic acid-gas binding materials to be reused. This enables transport of the liquid capture compounds and the release of the acid gases from the organic liquid with significant energy savings compared to current aqueous systems.

  12. Rankine vortex evolution in a gas with heat release source

    NASA Astrophysics Data System (ADS)

    Zavershinskii, I. P.; Klimov, A. I.; Molevich, N. E.; Porfir'ev, D. P.

    2009-04-01

    The influence of a heat release source with temperature-dependent power on the stability of a Rankine vortex has been studied. A condition for the formation of a radially convergent swirling flow with increasing vorticity is found for a medium with a positive feedback between nonequilibrium heat release perturbations and the pressure at the vortex core.

  13. Radiative accidental matter

    NASA Astrophysics Data System (ADS)

    Sierra, D. Aristizabal; Simoes, C.; Wegman, D.

    2016-07-01

    Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number violation. We study such scenarios assuming that the new physics plays an active role in neutrino mass generation, and show that this unavoidably leads to radiatively induced neutrino masses. We systematically classify all possible models and determine their viability by studying electroweak precision data, big bang nucleosynthesis and electroweak perturbativity, finding that the latter places the most stringent constraints on the mass spectra. These results allow the identification of minimal radiative accidental matter models for which perturbativity is lost at high scales. We calculate radiative charged-lepton flavor violating processes in these setups, and show that μ → eγ has a rate well within MEG sensitivity provided the lepton-number violating scale is at or below 5×105 GeV, a value (naturally) assured by the radiative suppression mechanism. Sizeable τ → μγ branching fractions within SuperKEKB sensitivity are possible for lower lepton-number breaking scales. We thus point out that these scenarios can be tested not only in direct searches but also in lepton flavor-violating experiments.

  14. A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

    SciTech Connect

    SD Rassat; PA Gauglitz; SM Caley; LA Mahoney; DP Mendoza

    1999-02-23

    The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Allemann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to percolati

  15. Accidental condom inhalation.

    PubMed

    Arya, C L; Gupta, Rajnish; Arora, V K

    2004-01-01

    A 27-year-old lady presented with persistent cough, sputum and fever for the preceding six months. Inspite of trials with antibiotics and anti-tuberculosis treatment for the preceeding four months, her symptoms did not improve. A subsequent chest radiograph showed non-homogeneous collapse-consolidation of right upper lobe. Videobronchoscopy revealed an inverted bag like structure in right upper lobe bronchus and rigid bronchoscopic removal with biopsy forceps confirmed the presence of a condom. Detailed retrospective history also confirmed accidental inhalation of the condom during fellatio. PMID:14870871

  16. Bench-Scale Evaluation of Gas Ebullition On The Release of Contaminants From Sediments

    EPA Science Inventory

    The release of gas bubbles from sediments into overlying water (ebullition) is a major mechanism for the discharge of biogenic and geogenic gases into the water body. Microbial breakdown of sedimentary organic matter produces gas bubbles which are inherently hydrophobic and tend...

  17. Accidental acute exposure to doxorubicin.

    PubMed

    Curran, C F; Luce, J K

    1989-12-01

    Accidental ocular exposure to doxorubicin was followed by no reaction or rapidly resolving conjunctivitis in 13 of 15 cases (87%). In the two remaining cases, persistent photophobia and chronic inflammation were reported. Of 28 accidental exposures to sites other than the eyes, no reactions or rapidly resolving local reactions were reported in 24 cases (86%). Nurses are at particular risk for accidental exposure to doxorubicin and accounted for 20 of the 43 reported exposures (47%). PMID:2590899

  18. Dynamics of Crust Dissolution and Gas Release in Tank 241-SY-101

    SciTech Connect

    SD Rassat; CW Stewart; BE Wells; WL Kuhn; ZI Antoniak; JM Cuta; KP Recknagle; G Terrones; VV Viswanathan; JH Sukamto; DP Mendoza

    2000-01-26

    Due primarily to an increase in floating crust layer thickness, the waste level in Hanford Tank 241-SY-101 (SY-101) has grown appreciably, and the flammable gas volume stored in the crust has become a potential hazard. To remediate gas retention in the crust and the potential for buoyant displacement gas releases from the nonconnective layer at the bottom of the tank, SY-101 will be diluted to dissolve a large fraction of the solids that allow the waste to retain gas. In this work we develop understanding of the state of the tank waste and some of its physical properties, investigate how added water will be distributed in the tank and affect the waste, and use the information to evaluate mechanisms and rates of waste solids dissolution and gas release. This work was completed to address these questions and in support of planning and development of controls for the SY-101 Surface Level Rise Remediation Project. Particular emphasis is given to dissolution of and gas release from the crust, although the effects of back-dilution on all waste layers are addressed. The magnitude and rates of plausible gas release scenarios are investigated, and it is demonstrated that none of the identified mechanisms of continuous (dissolution-driven) or sudden gas release, even with conservative assumptions, lead to domespace hydrogen concentrations exceeding the lower flammability limit. This report documents the results of studies performed in 1999 to address the issues of the dynamics, of crust dissolution and gas release in SY-101. It contains a brief introduction to the issues at hand; a summary of our knowledge of the SY-101 crust and other waste properties, including gas fractions, strength and volubility; a description of the buoyancy and dissolution models that are applied to predict the crust response to waste transfers and back dilution; and a discussion of the effectiveness of mixing for water added below the crust and the limited potential for significant stratification

  19. Characteristics of pollutant gas releases from swine, dairy, beef, and layer manure, and municipal wastewater.

    PubMed

    Dai, Xiao-Rong; Saha, Chayan Kumer; Ni, Ji-Qin; Heber, Albert J; Blanes-Vidal, Victoria; Dunn, James L

    2015-06-01

    Knowledge about characteristics of gas releases from various types of organic wastes can assist in developing gas pollution reduction technologies and establishing environmental regulations. Five different organic wastes, i.e., four types of animal manure (swine, beef, dairy, and layer hen) and municipal wastewater, were studied for their characteristics of ammonia (NH3), carbon dioxide (CO2), hydrogen sulfide (H2S), and sulfur dioxide (SO2) releases for 38 or 43 days in reactors under laboratory conditions. Weekly waste additions and continuous reactor headspace ventilation were supplied to simulate waste storage conditions. Results demonstrated that among the five waste types, layer hen manure and municipal wastewater had the highest and lowest NH3 release potentials, respectively. Layer manure had the highest and dairy manure had the lowest CO2 release potentials. Dairy manure and layer manure had the highest and lowest H2S release potentials, respectively. Beef manure and layer manure had the highest and lowest SO2 releases, respectively. The physicochemical characteristics of the different types of wastes, especially the total nitrogen, total ammoniacal nitrogen, dry matter, and pH, had strong influence on the releases of the four gases. Even for the same type of waste, the variation in physicochemical characteristics affected the gas releases remarkably. PMID:25794466

  20. Hydrocarbon Release During Fuel Storage and Transfer at Gas Stations: Environmental and Health Effects.

    PubMed

    Hilpert, Markus; Mora, Bernat Adria; Ni, Jian; Rule, Ana M; Nachman, Keeve E

    2015-12-01

    At gas stations, fuel is stored and transferred between tanker trucks, storage tanks, and vehicle tanks. During both storage and transfer, a small fraction of unburned fuel is typically released to the environment unless pollution prevention technology is used. While the fraction may be small, the cumulative release can be substantial because of the large quantities of fuel sold. The cumulative release of unburned fuel is a public health concern because gas stations are widely distributed in residential areas and because fuel contains toxic and carcinogenic chemicals. We review the pathways through which gasoline is chronically released to atmospheric, aqueous, and subsurface environments, and how these releases may adversely affect human health. Adoption of suitable pollution prevention technology should not only be based on equipment and maintenance cost but also on energy- and health care-saving benefits. PMID:26435043

  1. Fission gas release from UO{sub 2+x} in defective light water reactor fuel rods

    SciTech Connect

    Skim, Y. S.

    1999-11-12

    A simplified semi-empirical model predicting fission gas release form UO{sub 2+x} fuel to the fuel rod plenum as a function of stoichiometry excess (x) is developed to apply to the fuel of a defective LWR fuel rod in operation. The effect of fuel oxidation in enhancing gas diffusion is included as a parabolic dependence of the stoichiometry excess. The increase of fission gas release in a defective BWR fuel rod is at the most 3 times higher than in an intact fuel rod because of small extent of UO{sub 2} oxidation. The major enhancement contributor in fission gas release of UO{sub 2+x} fuel is the increased diffusivity due to stoichiometry excess rather than the higher temperature caused by degraded fuel thermal conductivity.

  2. Preventing Buoyant Displacement Gas Release Events in Hanford Double-Shell Waste Tanks

    SciTech Connect

    Meyer, Perry A.; Stewart, Charles W.

    2001-01-01

    This report summarizes the predictive methods used to ensure that waste transfer operations in Hanford waste tanks do not create waste configurations that lead to unsafe gas release events. The gas release behavior of the waste in existing double-shell tanks has been well characterized, and the flammable gas safety issues associated with safe storage of waste in the current configuration are being formally resolved. However, waste is also being transferred between double-shell tanks and from single-shell tanks into double-shell tanks by saltwell pumping and sluicing that create new wastes and waste configurations that have not been studied as well. Additionally, planning is underway for various waste transfer scenarios to support waste feed delivery to the proposed vitrification plant. It is critical that such waste transfers do not create waste conditions with the potential for dangerous gas release events.

  3. Numerical simulation of high pressure release and dispersion of hydrogen into air with real gas model

    NASA Astrophysics Data System (ADS)

    Khaksarfard, R.; Kameshki, M. R.; Paraschivoiu, M.

    2010-06-01

    Hydrogen is a renewable and clean source of energy, and it is a good replacement for the current fossil fuels. Nevertheless, hydrogen should be stored in high-pressure reservoirs to have sufficient energy. An in-house code is developed to numerically simulate the release of hydrogen from a high-pressure tank into ambient air with more accuracy. Real gas models are used to simulate the flow since high-pressure hydrogen deviates from ideal gas law. Beattie-Bridgeman and Abel Noble equations are applied as real gas equation of state. A transport equation is added to the code to calculate the concentration of the hydrogen-air mixture after release. The uniqueness of the code is to simulate hydrogen in air release with the real gas model. Initial tank pressures of up to 70 MPa are simulated.

  4. Fission-gas release from uranium nitride at high fission rate density

    NASA Technical Reports Server (NTRS)

    Weinstein, M. B.; Kirchgessner, T. A.; Tambling, T. N.

    1973-01-01

    A sweep gas facility has been used to measure the release rates of radioactive fission gases from small UN specimens irradiated to 8-percent burnup at high fission-rate densities. The measured release rates have been correlated with an equation whose terms correspond to direct recoil release, fission-enhanced diffusion, and atomic diffusion (a function of temperature). Release rates were found to increase linearly with burnups between 1.5 and 8 percent. Pore migration was observed after operation at 1550 K to over 6 percent burnup.

  5. Pressure Systems Energy Release Protection (Gas Pressurized Systems)

    NASA Technical Reports Server (NTRS)

    Brown, S. J. (Editor)

    1986-01-01

    A survey of studies into hazards associated with closed or pressurized system rupture and preliminary guidelines for the performance design of primary, secondary, and protective receptors of these hazards are provided. The hazards discussed in the survey are: blast, fragments, ground motion, heat radiation, biological, and chemical. Performance guidelines for receptors are limited to pressurized systems that contain inert gas. The performance guidelines for protection against the remaining unaddressed degenerative hazards are to be covered in another study.

  6. STS-39 Critical Ionization Velocity (CIV) gas release from OV-103 payload bay

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A plume of nitrous oxide gas is released from a compressed gas canister mounted on the increased capacity adaptive payload carrier 1 (ICAPC-1) on the forward port side of Discovery's, Orbiter Vehicle (OV) 103's, payload bay (PLB). The gas release is part of the Critical Ionization Velocity (CIV) experiment conducted during STS-39. The Shuttle Pallet Satellite II (SPAS-II) 'parked' about two kilometers (km) away, is taking infrared, visible, and ultraviolet radiometric spatial, spectral, and temporal measurements of the gas plumes. Surrounding the CIV ICAPC-1 are: the ICAPC-2 payload support subsystem, radiometer, and Langmuir probe also mounted on the port side; the Space Test Payload 1 (STP-1) multipurpose experiment support structure (MPESS) (just beyond gas beam); and the Air Force Program 675 (AFP-675) experiment support structure (ESS).

  7. [Accidental methyl alcohol poisoning].

    PubMed

    Xiao, J H

    1990-05-01

    An accidental poisoning due to drinking methyl alcohol in Chaoyang county is reported, analysing the accident. The poison came from the "retail white spirit" which was contaminated with methyl alcohol. Twenty-nine persons drank the wine, fourteen of them died, two of them became blind. After drinking this "retail white spirit" the drinkers showed symptoms of vertigo, headache, weakness, vomiting, night sweat, dyspnea and blurring of vision etc. within 6-120 hours. On examining the remaining spirit, we found the content of methyl alcohol to be between 16.6 and 40.69 g/100 ml. Some of the patients' urine and blood also contained methyl alcohol. We reckoned that each one of the twenty patients had taken more than 27 g of methyl alcohol and each of the ten dead drank more than 40 ml of the alcohol. PMID:2253526

  8. Gas hydrate formation in the deep sea: In situ experiments with controlled release of methane, natural gas, and carbon dioxide

    USGS Publications Warehouse

    Brewer, P.G.; Orr, F.M., Jr.; Friederich, G.; Kvenvolden, K.A.; Orange, D.L.

    1998-01-01

    We have utilized a remotely operated vehicle (ROV) to initiate a program of research into gas hydrate formation in the deep sea by controlled release of hydrocarbon gases and liquid CO2 into natural sea water and marine sediments. Our objectives were to investigate the formation rates and growth patterns of gas hydrates in natural systems and to assess the geochemical stability of the reaction products over time. The novel experimental procedures used the carrying capacity, imaging capability, and control mechanisms of the ROV to transport gas cylinders to depth and to open valves selectively under desired P-T conditions to release the gas either into contained natural sea water or into sediments. In experiments in Monterey Bay, California, at 910 m depth and 3.9??C water temperature we find hydrate formation to be nearly instantaneous for a variety of gases. In sediments the pattern of hydrate formation is dependent on the pore size, with flooding of the pore spaces in a coarse sand yielding a hydrate cemented mass, and gas channeling in a fine-grained mud creating a veined hydrate structure. In experiments with liquid CO2 the released globules appeared to form a hydrate skin as they slowly rose in the apparatus. An initial attempt to leave the experimental material on the sea floor for an extended period was partially successful; we observed an apparent complete dissolution of the liquid CO2 mass, and an apparent consolidation of the CH4 hydrate, over a period of about 85 days.

  9. Measurement and analysis of fission gas release from BNFL's SBR MOX fuel

    NASA Astrophysics Data System (ADS)

    White, R. J.; Fisher, S. B.; Cook, P. M. A.; Stratton, R.; Walker, C. T.; Palmer, I. D.

    2001-01-01

    Puncture results are presented for seven SBR MOX fuel rods from the first prototypical commercial irradiation that was carried out in the Beznau-1 PWR. The rod average burn-up ranged from 31.2 to 35.6 MWd/kgHM. Comparison is made with the percentage of gas released from French MOX fuels and UO 2 fuel. The results show that in the burn-up range investigated, SBR MOX fuel and MIMAS MOX fuel perform similarly, releasing up to about 1% of the fission gas inventory. Comparisons with the Halden Criterion show that SBR MOX has the same release threshold as UO 2 and this suggests that the mechanisms of release in the two fuels are similar. This is further supported by calculations made with the ENIGMA fuel performance code. It is concluded that the apparent differences in fission gas release between SBR MOX and UO 2 fuel, at least in the early stages of release, can be explained by the higher temperatures experienced by MOX fuel.

  10. The Effects of Neutral Gas Release on Vehicle Charging: Experiment and Theory

    NASA Astrophysics Data System (ADS)

    Walker, D. N.; Amatucci, W. E.; Bowles, J. H.; Fernsler, R. F.; Siefring, C. L.; Antoniades, J. A.; Keskinen, M. J.

    1998-11-01

    This paper describes an experimental and theoretical research effort related to the mitigation of spacecraft charging by Neutral Gas Release (NGR). The Space Power Experiments Aboard Rockets programs (SPEAR I and III) [Mandel et al., 1998; Berg et al., 1995] and other earlier efforts have demonstrated that NGR is an effective method of controlling discharges in space. The laboratory experimentswere conducted in the large volume Space Physics Simulation Chamber (SPSC) at the Naval Research Laboratory (NRL). A realistic near-earth space environment can be simulated in this device for whichminimumscalingneeds to be performedtorelate the data to space plasma regimes. This environment is similar to that encountered by LEO spacecraft, e.g., the Space Station, Shuttle, and high inclination satellites. The experimental arrangement consists of an aluminum cylinder which can be biased to high negative voltage (0.4 kVgas release valve designed for millisec release times, a pressure-regulated neutral gas reservoir, and variable Mach number nozzles. After the cylinder is charged to high voltage, the neutral gas is released, inducing a breakdown of the gas in the strong electric field about the cylinder. Collection of ions from the newly created dense plasma, along with secondary electron emission from the cylinder surface, provide the return current necessary for grounding the body. The theoretical treatment assumes a simple Townsend discharge along with the fundamental assumption of exponential electron growth in an avalanche fashion as one proceeds from the cathode toward the anode during neutral gas breakdown in the presence of high potentials. In addition the nozzle release of neutral gas is modeled and a simple linear spatial dependence of the applied potential is assumed. This basic model produces quite good results when compared to the experiment.

  11. Effects of Globally Waste-Disturbing Activities on Gas Generation, Retention, and Release in Hanford Waste Tanks

    SciTech Connect

    Stewart, Charles W. ); Huckaby, James L. ); Meyer, Perry A. )

    2002-08-30

    Various operations are authorized in Hanford single-shell and double-shell tanks that disturb all or a large fraction of the waste. These globally waste-disturbing activities have the potential to release a significant volume of retained gas. Analyses are presented for expected gas release mechanisms and the potential release rates and volumes resulting from these activities. Recommendations for gas monitoring and assessment of the potential for changes in tank classification and steady-state flammability are also given.

  12. EQUATIONS FOR GAS RELEASING PROCESS FROM PRESSURIZED VESSELS IN ODH EVALUATION.

    SciTech Connect

    JIA,L.X.; WANG,L.

    2001-07-16

    IN THE EVALUATION OF ODH, THE CALCULATION OF THE SPILL RATE FROM THE PRESSURIZED VESSEL IS THE CENTRAL TASK. THE ACCURACY OF THE ENGINEERING ESTIMATION BECOMES ONE OF THE SAFETY DESIGN ISSUES. THIS PAPER SUMMARIZES THE EQUATIONS FOR THE OXYGEN CONCENTRATION CALCULATION IN DIFFERENT CASES, AND DISCUSSES THE EQUATIONS FOR THE GAS RELEASE PROCESS CALCULATION BOTH FOR THE HIGH-PRESSURE GAS TANK AND THE LOW-TEMPERATURE LIQUID CONTAINER.

  13. Epidemiology of accidental radiation exposures.

    PubMed Central

    Cardis, E

    1996-01-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental radiation exposures, and discuss information that could be obtained from studies of accidental exposures and the types of studies that are needed. PMID:8781398

  14. Environmental controls of greenhouse gas release in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-01-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain greenhouse gas release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  15. Estimating methane releases from natural gas production and transmission in Russia

    NASA Astrophysics Data System (ADS)

    Dedikov, J. V.; Akopova (Vniigaz), G. S.; Gladkaja (Vniigaz), N. G.; Piotrovskij (Tyumentransgaz), A. S.; Markellov (Volgotransgaz), V. A.; Salichov (Yamburggazdabuicha), S. S.; Kaesler, H.; Ramm, A.; Müller von Blumencron, A.; Lelieveld, J.

    Methane releases from the RAO Gazprom gas production and transmission facilities in Russia were determined in an extensive measurement program carried out in 1996 and 1997. Subsequently, the measurements were extrapolated to the Russian scale. The results show that methane releases from gas transmission are less than 1% of throughput. Methane loss from gas production in northwestern Siberia appears to be relatively small, generally less than 0.1%. The largest methane emissions result from venting during maintenance and repairs, leaks from valves on transmission lines, and from compressor stations. The measurements show that, in the case of leaks, a limited number of major ones accounts for most of the methane releases. Methane emissions expressed as a percentage of the gas volume produced or transported are (rounded figures): production and processing 0.1%, pipelines 0.2%, compressor stations 0.7%, so that the total release by production and transmission in Russia amounts to about 1.0%, i.e. ˜5.4×10 9 m 3/a (˜4 Tg/a). This is consistent with our previous preliminary estimates, indicating that maximum emissions are 1.5-1.8%/a. However, this is generally lower than most other estimates and speculations.

  16. Impact of Dissociation and Sensible Heat Release on Pulse Detonation and Gas Turbine Engine Performance

    NASA Technical Reports Server (NTRS)

    Povinelli, Louis A.

    2001-01-01

    A thermodynamic cycle analysis of the effect of sensible heat release on the relative performance of pulse detonation and gas turbine engines is presented. Dissociation losses in the PDE (Pulse Detonation Engine) are found to cause a substantial decrease in engine performance parameters.

  17. Effects of Globally Waste-Disturbing Activities on Gas Generation, Retention, and Release in Hanford Waste Tanks

    SciTech Connect

    Stewart, Charles W.; Huckaby, James L.; Meyer, Perry A.

    2003-07-30

    Various operations are authorized in Hanford tanks that disturb all or much of the waste. The globally waste-disturbing activities have the potential to release a large fraction of the retained flammable gas and to affect future gas generation, retention, and release behavior. This report presents analyses of the expected flammable gas release mechanisms and the potential release rates and volumes resulting from these activities. The background of the flammable gas safety issue at Hanford is summarized, as is the current understanding of gas generation, retention, and release phenomena. Considerations for gas monitoring and assessment of the potential for changes in tank classification and steady-state flammability are given. This revision (Rev. 2)incorporates additional comments from Office of River Protection reviewers. An appendix presents the checklist for technical peer review of Revision 1 of this report.

  18. Effects of Globally Waste-Disturbing Activities on Gas Generation, Retention, and Release in Hanford Waste Tanks

    SciTech Connect

    Stewart, Charles W.; Huckaby, James L.; Meyer, Perry A.

    2002-12-18

    Various operations are authorized in Hanford single- and double-shell tanks that disturb all or a large fraction of the waste. These globally waste-disturbing activities have the potential to release a large fraction of the retained flammable gas and to affect future gas generation, retention, and release behavior. This report presents analyses of the expected flammable gas release mechanisms and the potential release rates and volumes resulting from these activities. The background of the flammable gas safety issue at Hanford is summarized, as is the current understanding of gas generation, retention, and release phenomena. Considerations for gas monitoring and assessment of the potential for changes in tank classification and steady-state flammability are given.

  19. PolyPole-1: An accurate numerical algorithm for intra-granular fission gas release

    NASA Astrophysics Data System (ADS)

    Pizzocri, D.; Rabiti, C.; Luzzi, L.; Barani, T.; Van Uffelen, P.; Pastore, G.

    2016-09-01

    The transport of fission gas from within the fuel grains to the grain boundaries (intra-granular fission gas release) is a fundamental controlling mechanism of fission gas release and gaseous swelling in nuclear fuel. Hence, accurate numerical solution of the corresponding mathematical problem needs to be included in fission gas behaviour models used in fuel performance codes. Under the assumption of equilibrium between trapping and resolution, the process can be described mathematically by a single diffusion equation for the gas atom concentration in a grain. In this paper, we propose a new numerical algorithm (PolyPole-1) to efficiently solve the fission gas diffusion equation in time-varying conditions. The PolyPole-1 algorithm is based on the analytic modal solution of the diffusion equation for constant conditions, combined with polynomial corrective terms that embody the information on the deviation from constant conditions. The new algorithm is verified by comparing the results to a finite difference solution over a large number of randomly generated operation histories. Furthermore, comparison to state-of-the-art algorithms used in fuel performance codes demonstrates that the accuracy of PolyPole-1 is superior to other algorithms, with similar computational effort. Finally, the concept of PolyPole-1 may be extended to the solution of the general problem of intra-granular fission gas diffusion during non-equilibrium trapping and resolution, which will be the subject of future work.

  20. Dexamethasone-releasing biodegradable polymer scaffolds fabricated by a gas-foaming/salt-leaching method.

    PubMed

    Yoon, Jun Jin; Kim, Jung Hoe; Park, Tae Gwan

    2003-06-01

    Dexamethasone, a steroidal anti-inflammatory drug, was incorporated into porous biodegradable polymer scaffolds for sustained release. The slowly released dexamethasone from the degrading scaffolds was hypothesized to locally modulate the proliferation and differentiation of various cells. Dexamethasone containing porous poly(D,L-lactic-co-glycolic acid) (PLGA) scaffolds were fabricated by a gas-foaming/salt-leaching method. Dexamethasone was loaded within the polymer phase of the PLGA scaffold in a molecularly dissolved state. The loading efficiency of dexamethasone varied from 57% to 65% depending on the initial loading amount. Dexamethasone was slowly released out in a controlled manner for over 30 days without showing an initial burst release. Release amount and duration could be adjusted by controlling the initial loading amount within the scaffolds. Released dexamethasone from the scaffolds drastically suppressed the proliferations of lymphocytes and smooth muscle cells in vitro. This study suggests that dexamethasone-releasing PLGA scaffolds could be potentially used either as an anti-inflammatory porous prosthetic device or as a temporal biodegradable stent for reducing intimal hyperplasia in restenosis. PMID:12699670

  1. Novel Solid Encapsulation of Ethylene Gas Using Amorphous α-Cyclodextrin and the Release Characteristics.

    PubMed

    Ho, Binh T; Bhandari, Bhesh R

    2016-05-01

    This research investigated the encapsulation of ethylene gas into amorphous α-cyclodextrins (α-CDs) at low (LM) and high (HM) moisture contents at 1.0-1.5 MPa for 24-120 h and its controlled release characteristics at 11.2-52.9% relative humidity (RH) for 1-168 h. The inclusion complexes (ICs) were characterized using X-ray diffractometry (XRD), nuclear magnetic resonance spectroscopy (CP-MAS (13)C NMR), and scanning electron microscopy (SEM). Ethylene concentrations in the ICs were from 0.45 to 0.87 mol of ethylene/mol CD and from 0.42 to 0.54 mol of ethylene/mol CD for LM and HM α-CDs, respectively. Ethylene gas released from the encapsulated powder at higher rates with increasing RH. An analysis of release kinetics using Avrami's equation showed that the LM and HM amorphous α-CDs were not associated with significant differences in release constant k and parameter n for any given RH condition. NMR spectra showed the presence of the characteristic carbon-carbon double bond of ethylene gas in the encapsulated α-CD powder. PMID:27071729

  2. Gas Generation and Release in Near-Surface Repository at Armenian NPP - 13372

    SciTech Connect

    Grigoryan, G.; Amirjanyan, A.; Hovhannisyan, A.; Gondakyan, Y.

    2013-07-01

    The potential nuclear waste repository at Armenian Nuclear Power Plant (ANPP) can store Low and Intermediate Level Radioactive waste (LL/ILW). In this kind of near-surface repository for radioactive waste, significant quantities of gases may be generated as a result of microbial degradation and corrosion. A discussion is presented of the microbial and chemical degradation of cellulose. For the release of gas, it is assumed that the complete conversion of cellulosic wastes to gases by the action of microbes, is, in principle, permitted. Released radioactive gases such as {sup 14}CO{sub 2} and {sup 14}CH{sub 4} could have a direct pathway to the atmosphere. The potential impact of gas generation, accumulation and migration on the long-term of repository, should therefore be assessed properly. We present here safety assessment result of gas producing radioactive waste disposal by the inhalation dose to a maximally exposed individual above ground, based on some conservative assumptions about release from waste as well as gas generation calculations. (authors)

  3. Developments in EPA`s air dispersion modeling for hazardous/toxic releases

    SciTech Connect

    Touma, J.S.

    1995-12-31

    Title 3 of the 1990 Clean Air Act Amendments (CAAA) lists many chemicals as hazardous air pollutants and requires establishing regulations to prevent their accidental release, and to minimize the consequence, if any such releases occur. With the large number of potential release scenarios that are associated with these chemicals, there is a need for a systematic approach for applying air dispersion models to estimate impact. Because some chemicals may form dense gas clouds upon release, and dispersion models that can simulate these releases are complex, EPA has paid attention to the development of modeling tools and guidance on the use of models that can address these types of releases.

  4. Non-Volcanic release of CO2 in Italy: quantification, conceptual models and gas hazard

    NASA Astrophysics Data System (ADS)

    Chiodini, G.; Cardellini, C.; Caliro, S.; Avino, R.

    2011-12-01

    Central and South Italy are characterized by the presence of many reservoirs naturally recharged by CO2 of deep provenance. In the western sector, the reservoirs feed hundreds of gas emissions at the surface. Many studies in the last years were devoted to (i) elaborating a map of CO2 Earth degassing of the region; (ii) to asses the gas hazard; (iii) to develop methods suitable for the measurement of the gas fluxes from different types of emissions; (iv) to elaborate the conceptual model of Earth degassing and its relation with the seismic activity of the region and (v) to develop physical numerical models of CO2 air dispersion. The main results obtained are: 1) A general, regional map of CO2 Earth degassing in Central Italy has been elaborated. The total flux of CO2 in the area has been estimated in ~ 10 Mt/a which are released to the atmosphere trough numerous dangerous gas emissions or by degassing spring waters (~ 10 % of the CO2 globally estimated to be released by the Earth trough volcanic activity). 2) An on line, open access, georeferenced database of the main CO2 emissions (~ 250) was settled up (http://googas.ov.ingv.it). CO2 flux > 100 t/d characterise 14% of the degassing sites while CO2 fluxes from 100 t/d to 10 t/d have been estimated for about 35% of the gas emissions. 3) The sites of the gas emissions are not suitable for life: the gas causes many accidents to animals and people. In order to mitigate the gas hazard a specific model of CO2 air dispersion has been developed and applied to the main degassing sites. A relevant application regarded Mefite d'Ansanto, southern Apennines, which is the largest natural emission of low temperature CO2 rich gases, from non-volcanic environment, ever measured in the Earth (˜2000 t/d). Under low wind conditions, the gas flows along a narrow natural channel producing a persistent gas river which has killed over a period of time many people and animals. The application of the physical numerical model allowed us to

  5. Relationships between gas geochemistry and release rates and the geomechanical state of igneous rock massifs

    NASA Astrophysics Data System (ADS)

    Nivin, Valentin A.; Belov, Nikolai I.; Treloar, Peter J.; Timofeyev, Vladimir V.

    2001-07-01

    In contrast to sedimentary sequences, the relationships between the stressed state of igneous rocks and the chemistry and physical properties of gases contained within them are not well known. Here, we attempt to fill this gap by using, as an example, the apatite-nepheline and rare-metal ore deposits hosted within the Khibiny and Lovozero alkaline nepheline-syenite complexes of the Kola Peninsula, NW Russia. These massifs are characterized by unusually high, for igneous rocks, contents of multi-component, essentially hydrogen-hydrocarbon, gases and also by high hardness, elasticity and unevenly distributed, subhorizontal tectonic stresses. Relationships between the chemical and dynamic characteristics of the gases and the geomechanical properties of the host rocks have been examined using field observations and laboratory experiments. Patterns of gas release variations in time and space, gas emissions from rock pillars during artificial loading, variations of gas pressure in sealed shot-holes and changes in liberation rates of gaseous components during experimental rock loading are suggested to result from changes in rock stress and deformation state. Gas compositions in sealed shot-holes in stressed rocks change with time. Partly, this is due to belated release of gases held in fluid inclusions and isolated voids and their subsequent mixing with gases held in interconnected fracture systems as the included gases are preferentially released as fluid inclusion arrays are opened during later stages of stress build-up. Partly, it may also be because released gases may react with new fracture surfaces to generate enhanced levels of reduced H 2 gases.

  6. Arctic greenhouse-gas storage and release modulated by late-glacial ice sheet fluctuations

    NASA Astrophysics Data System (ADS)

    Portnov, Alexey; Mienert, Jurgen; Vadakkepuliyambatta, Sunil; Patton, Henry; Andreassen, Karin; Winsborrow, Monica; Knies, Jochen; Hubbard, Alun I.

    2016-04-01

    The subglacial footprint of the Barents Sea Ice sheet which advanced across northern Eurasia from 26 to 22 ka BP had a major impact on the underlying gas hydrate stability zone (GHSZ) leading to storage of methane and other hydrocarbons. With the onset of deglaciation, these hydrocarbon rich hydrates dissociated, releasing potent greenhouse gas into the ocean and possibly atmosphere over a period of thousands of years. We present a wide-range of observational data acquired from offshore western Svalbard and the Barents Sea to robustly constrain a coupled model of the subglacial evolution of gas hydrate reservoirs during and after the Last Glacial Maximum (LGM). Our results indicate that even under minimum ice thickness reconstructions, an extensive, ~500-meter thick GHSZ existed beneath the ice sheet in our study area offshore of western Svalbard (Portnov et al., 2016). An offshore corridor of methane release did though also persist throughout maximum ice conditions on the upper continental margin. Throughout the LGM a marine ice sheet directly comparable to those of Greenland and Antarctica today inundated the continental margin offshore of western Svalbard and the vast shelf areas of the Barents Sea. However, with climatic amelioration the Barents Sea ice sheet experienced a 4ka period of dynamic retreat with concurrent flooding of the shelf by rising sea levels, which provided a high magnitude perturbation to the substrate pressure and temperature domains. By analogy, the future response of Polar ice sheets is an emerging concern as their ongoing thinning and retreat will likewise perturb the present day subglacial GHSZ leading to potential widespread gas hydrate destabilisation and release. Portnov, Alexey, et al. "Ice-sheet-driven methane storage and release in the Arctic", Nature Comm. DOI: 10.1038/ncomms10314. (2016).

  7. 76 FR 3142 - Release of Exposure Draft Technical Bulletins; Accounting for Oil and Gas Resources and Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... ADVISORY BOARD Release of Exposure Draft Technical Bulletins; Accounting for Oil and Gas Resources and Federal Natural Resources Other Than Oil and Gas AGENCY: Federal Accounting Standards Advisory Board... Bulletin 2011-1, Accounting for Federal Natural Resources Other Than Oil and Gas, and an Exposure...

  8. Models for recurrent gas release event behavior in hazardous waste tanks

    SciTech Connect

    Anderson, D.N.; Arnold, B.C.

    1994-08-01

    Certain radioactive waste storage tanks at the United States Department of Energy Hanford facilities continuously generate gases as a result of radiolysis and chemical reactions. The congealed sludge in these tanks traps the gases and causes the level of the waste within the tanks to rise. The waste level continues to rise until the sludge becomes buoyant and ``rolls over``, changing places with heavier fluid on top. During a rollover, the trapped gases are released, resulting, in a sudden drop in the waste level. This is known as a gas release event (GRE). After a GRE, the wastes leading to another GRE. We present nonlinear time waste re-congeals and gas again accumulates leading to another GRE. We present nonlinear time series models that produce simulated sample paths that closely resemble the temporal history of waste levels in these tanks. The models also imitate the random GRE, behavior observed in the temporal waste level history of a storage tank. We are interested in using the structure of these models to understand the probabilistic behavior of the random variable ``time between consecutive GRE`s``. Understanding the stochastic nature of this random variable is important because the hydrogen and nitrous oxide gases released from a GRE, are flammable and the ammonia that is released is a health risk. From a safety perspective, activity around such waste tanks should be halted when a GRE is imminent. With credible GRE models, we can establish time windows in which waste tank research and maintenance activities can be safely performed.

  9. Crystallization, sublimation, and gas release in the interior of a porous comet nucleus

    NASA Technical Reports Server (NTRS)

    Prialnik, Dina

    1992-01-01

    A numerical code is developed for evolutionary calculations of the thermal structure and composition of a porous comet nucleus made of water ice, in amorphous or crystalline form, other volatiles, dust, and gases trapped in amorphous ice. Bulk evaporation, crystallization, gas release, and free (Knudsen) flow of gases through the pores are taken into account. The numerical scheme yields exact conservation laws for mass and energy. The code is used to study the effect of bulk evaporation of ice in the interior of a comet nucleus during crystallization. It is found that evaporation controls the temperature distribution; the vapor prevents cooling of the crystallized layer of ice, by recondensation and release of latent heat. Thus high temperatures are maintained below the surface of the nucleus and down to depths of tens or hundreds of meters, even at large heliocentric distances, as long as crystallization goes on. Gas trapped in the ice and released during the phase transition flows both toward the interior and toward the surface and out of the nucleus. The progress of crystallization is largely determined by the contribution of gas fluxes to heat transfer.

  10. Fission Product Monitoring and Release Data for the Advanced Gas Reactor -1 Experiment

    SciTech Connect

    Dawn M. Scates; John B. Walter; Jason M. Harp; Mark W. Drigert; Edward L. Reber

    2010-10-01

    The AGR-1 experiment is a fueled multiple-capsule irradiation experiment that was irradiated in the Advanced Test Reactor (ATR) from December 26, 2006 until November 6, 2009 in support of the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) Fuel Development and Qualification program. An important measure of the fuel performance is the quantification of the fission product releases over the duration of the experiment. To provide this data for the inert fission gasses(Kr and Xe), a fission product monitoring system (FPMS) was developed and implemented to monitor the individual capsule effluents for the radioactive species. The FPMS continuously measured the concentrations of various krypton and xenon isotopes in the sweep gas from each AGR-1 capsule to provide an indicator of fuel irradiation performance. Spectrometer systems quantified the concentrations of Kr-85m, Kr-87, Kr-88, Kr-89, Kr-90, Xe-131m, Xe-133, Xe 135, Xe 135m, Xe-137, Xe-138, and Xe-139 accumulated over repeated eight hour counting intervals.-. To determine initial fuel quality and fuel performance, release activity for each isotope of interest was derived from FPMS measurements and paired with a calculation of the corresponding isotopic production or birthrate. The release activities and birthrates were combined to determine Release-to-Birth ratios for the selected nuclides. R/B values provide indicators of initial fuel quality and fuel performance during irradiation. This paper presents a brief summary of the FPMS, the release to birth ratio data for the AGR-1 experiment and preliminary comparisons of AGR-1 experimental fuels data to fission gas release models.

  11. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Prevention of accidental ignition. 192.751 Section 192.751 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention...

  12. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Prevention of accidental ignition. 192.751 Section 192.751 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY...

  13. Epidemiology of accidental radiation exposures

    SciTech Connect

    Cardis, E.

    1996-05-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental exposures and the types of studies that are needed. 64 refs., 3 tabs.

  14. Substrate lability and plant activity controls greenhouse gas release from Neotropical peatland

    NASA Astrophysics Data System (ADS)

    Sjogersten, Sofie; Hoyos, Jorge; Lomax, Barry; Turner, Ben; Wright, Emma

    2014-05-01

    Almost one third of global CO2 emissions resulting from land use change and substantial CH4 emissions originate from tropical peatlands. However, our understanding of the controls of CO2 and CH4 release from tropical peatlands are limited. The aim of this study was to investigate the role of peat lability and the activity of the vegetation on gas release using a combination of field and laboratory experiments. We demonstrated that peat lability constrained CH4 production to the surface peat under anaerobic conditions. The presence of plants shifted the C balance from a C source to a C sink with respect to CO2 while the activity of the root system strongly influenced CH4 emissions through its impact on soil O2 inputs. Both field and laboratory data suggest a coupling between the photosynthetic activity of the vegetation and the release of both CO2 and CH4 following the circadian rhythm of the dominant plant functional types. Forest clearance for agriculture resulted in elevated CH4 release, which we attribute in part to the cessation of root O2 inputs to the peat. We conclude that high emissions of CO2 and CH4 from forested tropical peatlands are likely driven by labile C inputs from the vegetation but that root O2 release may limit CH4 emissions.

  15. Modeling the influence of bubble pressure on grain boundary separation and fission gas release

    SciTech Connect

    Pritam Chakraborty; Michael R. Tonks; Giovanni Pastore

    2014-09-01

    Grain boundary (GB) separation as a mechanism for fission gas release (FGR), complementary to gas bubble interlinkage, has been experimentally observed in irradiated light water reactor fuel. However there has been limited effort to develop physics-based models incorporating this mechanism for the analysis of FGR. In this work, a computational study is carried out to investigate GB separation in UO2 fuel under the effect of gas bubble pressure and hydrostatic stress. A non-dimensional stress intensity factor formula is obtained through 2D axisymmetric analyses considering lenticular bubbles and Mode-I crack growth. The obtained functional form can be used in higher length-scale models to estimate the contribution of GB separation to FGR.

  16. The dynamics and modeling of heavier-than-air, cold gas releases

    NASA Astrophysics Data System (ADS)

    Zeman, Otto

    In this paper gravity currents are examined with special attention to heavier-than-air, cold gas releases such as liquefied natural gas spills. A simple, one-layer model is constructed which is capable of simulating: (1) the formation of the gravity flow by boiling the spilled liquefied gas; (2) the three-dimensional nature of the gravity flow in the presence of wind; and (3) convective heating and its contribution to the entrainment of ambient air. Similarity analysis reveals that if the initial (boil-off) period is represented by a boil-off velocity W b confined to a spill area of a dimension L o, then the characteristic velocity of the ensuing gravity current varies as ( WbLo) 1 3 and the scale of the current depth as (ifW bL o) 2 3. These scaling laws are shown to agree with the model predictions.

  17. Accidental degeneracies in string compactification

    NASA Astrophysics Data System (ADS)

    Bais, F. A.; Taormina, A.

    1986-11-01

    The equivalence of the torus and group manifold compactification of strings is established. Accidental degeneracies are shown to occur for a large class of compactifications. This way many examples are obtained in which modular invariance does not uniquely fix the representation content of the spectrum.

  18. A mathematical model for predicting the probability of acute mortality in a human population exposed to accidentally released airborne radionuclides. Final report for Phase I of the project: early effects of inhaled radionuclides

    SciTech Connect

    Filipy, R.E.; Borst, F.J.; Cross, F.T.; Park, J.F.; Moss, O.R.

    1980-06-01

    The report presents a mathematical model for the purpose of predicting the fraction of human population which would die within 1 year of an accidental exposure to airborne radionuclides. The model is based on data from laboratory experiments with rats, dogs and baboons, and from human epidemiological data. Doses from external, whole-body irradiation and from inhaled, alpha- and beta-emitting radionuclides are calculated for several organs. The probabilities of death from radiation pneumonitis and from bone marrow irradiation are predicted from doses accumulated within 30 days of exposure to the radioactive aerosol. The model is compared with existing similar models under hypothetical exposure conditions. Suggestions for further experiments with inhaled radionuclides are included.

  19. Trifluoromethyl Sulfur Pentafloride (SF5CF3), a Gas With Potential for Tracer Release Experiments

    NASA Astrophysics Data System (ADS)

    Smethie, W. M.; Ledwell, J. R.; Ho, D. T.

    2004-12-01

    SF5CF3 is chemically similar to SF6, a gas which has been used extensively in tracer release experiments, with a CF3 group substituted for a F atom in the molecular structure. It is a gas at atmospheric pressure and is present in the atmosphere with a mixing ratio of 0.12 ppt in 1999 [Sturges et al., Science, 289, 2000]. Sturges et al. (2000) measured a vertical profile of SF5CF3 and SF6 in Antarctic firn ice, showing that it has existed in the atmosphere for the last 3 decades and has increased over time with a trend that nearly parallels the increase of SF6. This suggests that its source could be related to the production and use of SF6, but there are also industrial processes for which it is a by-product. However, the exact source is not understood at this time. SF5CF3 is chemically stable with an estimated atmospheric lifetime of about 800 years [Takahashi et al., Geophys. Res. Lett., 29, 2002]. Because of its very low mixing ratio in the atmosphere and its chemical stability, it has very high potential for use in tracer release experiments. We have carried out some preliminary experiments to evaluate this potential. SF5CF3 can be measured in water samples by the same purge and trap - gas chromatographic procedure used for CFCs, has an ECD sensitivity slightly greater than SF6, and has a linear ECD response up to at least 80 fmoles. A preliminary determination of its solubility in fresh water revealed an Ostwald coefficient of 0.031 at 25 deg C, which is about half that of SF6. Its Ostwald coefficient in 1-octonol was measured to be about 3, roughly 7 times greater than for SF6. This suggests that SF5CF3 will have a greater affinity for organic matter than SF6. In open ocean tracer release experiments, SF6 is slowly transported downward in addition to its vertical spreading by diapycnal mixing. This could be caused by adsorption and release from sinking particles with organic phases, but the solubility of SF6 and SF5CF3 in 1-octanol indicate this effect is too

  20. Measurement of fission gas release from irradiated Usbnd Mo dispersion fuel samples

    NASA Astrophysics Data System (ADS)

    Burkes, Douglas E.; Casella, Amanda J.; Casella, Andrew M.

    2016-09-01

    The uranium-molybdenum (Usbnd Mo) alloy dispersed in an Alsbnd Si matrix has been proposed as one fuel design capable of converting some of the world's highest power research reactors from the use of high enriched uranium (HEU) to low enriched uranium (LEU). One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the extent of fission product release from the fuel under anticipated service environments. In this paper, two irradiated samples containing 53.9 vol% U-7wt% Mo fuel particles dispersed in an Al-2wt% Si matrix were subjected to specified thermal profiles under a controlled atmosphere using a thermogravimetric/differential thermal analyzer coupled with a mass spectrometer inside a hot cell. Measurements revealed three distinct fission gas release events for the samples from 400 to 700 °C, as well as a number of minor fission gas releases below and above this temperature range. The mechanisms responsible for these events are discussed, and the results have been compared with available information in the literature with exceptional agreement.

  1. An innovative acoustic sensor for first in-pile fission gas release determination - REMORA 3 experiment

    SciTech Connect

    Rosenkrantz, E.; Ferrandis, J. Y.; Augereau, F.; Lambert, T.; Fourmentel, D.; Tiratay, X.

    2011-07-01

    A fuel rod has been instrumented with a new design of an acoustic resonator used to measure in a non destructive way the internal rod plenum gas mixture composition. This ultrasonic sensor has demonstrated its ability to operate in pile during REMORA 3 irradiation experiment carried out in the OSIRIS Material Testing Reactor (CEA Saclay, France). Due to very severe experimental conditions such as temperature rising up to 150 deg.C and especially, high thermal fluence level up to 3.5 10{sup 19} n.cm{sup 2}, the initial sensor gas speed of sound efficiency measurement was strongly reduced due to the irradiation effects on the piezo-ceramic properties. Nevertheless, by adding a differential signal processing method to the initial data analysis procedure validated before irradiation, the gas resonance peaks were successfully extracted from the output signal. From these data, the molar fractions variations of helium and fission gas were measured from an adapted Virial state equation. Thus, with this sensor, the kinetics of gas release inside fuel rods could be deduced from the in-pile measurements and specific calculations. These data will also give information about nuclear reaction effect on piezo-ceramics sensor under high neutron and gamma flux. (authors)

  2. Analysis of fission gas release in LWR fuel using the BISON code

    SciTech Connect

    G. Pastore; J.D. Hales; S.R. Novascone; D.M. Perez; B.W. Spencer; R.L. Williamson

    2013-09-01

    Recent advances in the development of the finite-element based, multidimensional fuel performance code BISON of Idaho National Laboratory are presented. Specifically, the development, implementation and testing of a new model for the analysis of fission gas behavior in LWR-UO2 fuel during irradiation are summarized. While retaining a physics-based description of the relevant mechanisms, the model is characterized by a level of complexity suitable for application to engineering-scale nuclear fuel analysis and consistent with the uncertainties pertaining to some parameters. The treatment includes the fundamental features of fission gas behavior, among which are gas diffusion and precipitation in fuel grains, growth and coalescence of gas bubbles at grain faces, grain growth and grain boundary sweeping effects, thermal, athermal, and transient gas release. The BISON code incorporating the new model is applied to the simulation of irradiation experiments from the OECD/NEA International Fuel Performance Experiments database, also included in the IAEA coordinated research projects FUMEX-II and FUMEX-III. The comparison of the results with the available experimental data at moderate burn-up is presented, pointing out an encouraging predictive accuracy, without any fitting applied to the model parameters.

  3. Chloracne from the accidental production of tetrachlorodibenzodioxin

    PubMed Central

    May, George

    1973-01-01

    May, G. (1973).British Journal of Industrial Medicine,30, 276-283. Chloracne from the accidental production of tetrachlorodibenzodioxin. Following the accidental production of 2,3,7,8-tetrachlorodibenzodioxin (dioxin) as the result of an exothermic reaction at a chemical plant in Derbyshire, 79 cases of chloracne were recorded, many of them severe. Contrary to the usual experience they have responded very favourably to treatment and there were no cases of contact chloracne among relatives or domestic animals in the initial outbreak. However, two cases of contact chloracne were recorded three years later. Similar incidents are known to have occured in both Europe and the United States of America, almost invariably accompanied by widespread severe illness and with fatalities. Apart from one death due to an explosion which followed the exothermic reaction the more serious sequelae, which may range from depression and loss of weight to liver, kidney, and cardiac failure as well as malignant disease, have not occurred. A quick and reliable method of biological assay for the presence of dioxin in produced trichlorophenol was developed based on oral dosage to rabbits with assessment of liver function at fixed time intervals thereafter. This test has already been superseded by instantaneous gas-liquid chromatography. An entirely new plant with suitable modifications and multiple safety features has now been in satisfactory operation for three years. Images PMID:4269256

  4. Acoustic mapping of shallow water gas releases using shipborne multibeam systems

    NASA Astrophysics Data System (ADS)

    Urban, Peter; Köser, Kevin; Weiß, Tim; Greinert, Jens

    2015-04-01

    Water column imaging (WCI) shipborne multibeam systems are effective tools for investigating marine free gas (bubble) release. Like single- and splitbeam systems they are very sensitive towards gas bubbles in the water column, and have the advantage of the wide swath opening angle, 120° or more allowing a better mapping and possible 3D investigations of targets in the water column. On the downside, WCI data are degraded by specific noise from side-lobe effects and are usually not calibrated for target backscattering strength analysis. Most approaches so far concentrated on manual investigations of bubbles in the water column data. Such investigations allow the detection of bubble streams (flares) and make it possible to get an impression about the strength of detected flares/the gas release. Because of the subjective character of these investigations it is difficult to understand how well an area has been investigated by a flare mapping survey and subjective impressions about flare strength can easily be fooled by the many acoustic effects multibeam systems create. Here we present a semi-automated approach that uses the behavior of bubble streams in varying water currents to detect and map their exact source positions. The focus of the method is application of objective rules for flare detection, which makes it possible to extract information about the quality of the seepage mapping survey, perform automated noise reduction and create acoustic maps with quality discriminators indicating how well an area has been mapped.

  5. Accidental Turbulent Discharge Rate Estimation from Videos

    NASA Astrophysics Data System (ADS)

    Ibarra, Eric; Shaffer, Franklin; Savaş, Ömer

    2015-11-01

    A technique to estimate the volumetric discharge rate in accidental oil releases using high speed video streams is described. The essence of the method is similar to PIV processing, however the cross correlation is carried out on the visible features of the efflux, which are usually turbulent, opaque and immiscible. The key step in the process is to perform a pixelwise time filtering on the video stream, in which the parameters are commensurate with the scales of the large eddies. The velocity field extracted from the shell of visible features is then used to construct an approximate velocity profile within the discharge. The technique has been tested on laboratory experiments using both water and oil jets at Re ~105 . The technique is accurate to 20%, which is sufficient for initial responders to deploy adequate resources for containment. The software package requires minimal user input and is intended for deployment on an ROV in the field. Supported by DOI via NETL.

  6. Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change

    SciTech Connect

    Reagan, Matthew; Reagan, Matthew T.; Moridis, George J.

    2008-04-15

    Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating global climate, implicating global oceanic deposits of methane gas hydrate as the main culprit in instances of rapid climate change that have occurred in the past. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those predicted under future climate change scenarios, is poorly understood. To determine the fate of the carbon stored in these hydrates, we performed simulations of oceanic gas hydrate accumulations subjected to temperature changes at the seafloor and assessed the potential for methane release into the ocean. Our modeling analysis considered the properties of benthic sediments, the saturation and distribution of the hydrates, the ocean depth, the initial seafloor temperature, and for the first time, estimated the effect of benthic biogeochemical activity. The results show that shallow deposits--such as those found in arctic regions or in the Gulf of Mexico--can undergo rapid dissociation and produce significant methane fluxes of 2 to 13 mol/yr/m{sup 2} over a period of decades, and release up to 1,100 mol of methane per m{sup 2} of seafloor in a century. These fluxes may exceed the ability of the seafloor environment (via anaerobic oxidation of methane) to consume the released methane or sequester the carbon. These results will provide a source term to regional or global climate models in order to assess the coupling of gas hydrate deposits to changes in the global climate.

  7. Hydrogen Gas Retention and Release from WTP Vessels: Summary of Preliminary Studies

    SciTech Connect

    Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Mahoney, Lenna A.; Rassat, Scot D.; Wells, Beric E.; Bao, Jie; Boeringa, Gregory K.; Buchmiller, William C.; Burns, Carolyn A.; Chun, Jaehun; Karri, Naveen K.; Li, Huidong; Tran, Diana N.

    2015-07-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) is currently being designed and constructed to pretreat and vitrify a large portion of the waste in the 177 underground waste storage tanks at the Hanford Site. A number of technical issues related to the design of the pretreatment facility (PTF) of the WTP have been identified. These issues must be resolved prior to the U.S. Department of Energy (DOE) Office of River Protection (ORP) reaching a decision to proceed with engineering, procurement, and construction activities for the PTF. One of the issues is Technical Issue T1 - Hydrogen Gas Release from Vessels (hereafter referred to as T1). The focus of T1 is identifying controls for hydrogen release and completing any testing required to close the technical issue. In advance of selecting specific controls for hydrogen gas safety, a number of preliminary technical studies were initiated to support anticipated future testing and to improve the understanding of hydrogen gas generation, retention, and release within PTF vessels. These activities supported the development of a plan defining an overall strategy and approach for addressing T1 and achieving technical endpoints identified for T1. Preliminary studies also supported the development of a test plan for conducting testing and analysis to support closing T1. Both of these plans were developed in advance of selecting specific controls, and in the course of working on T1 it was decided that the testing and analysis identified in the test plan were not immediately needed. However, planning activities and preliminary studies led to significant technical progress in a number of areas. This report summarizes the progress to date from the preliminary technical studies. The technical results in this report should not be used for WTP design or safety and hazards analyses and technical results are marked with the following statement: “Preliminary Technical Results for Planning – Not to be used for WTP Design

  8. Periodic gas release from the LUSI mud volcano (East Java, Indonesia)

    NASA Astrophysics Data System (ADS)

    Vanderkluysen, L.; Burton, M. R.; Clarke, A. B.; Hartnett, H. E.; Smekens, J.

    2012-12-01

    The LUSI mud volcano has been erupting since May 2006 in a densely populated district of the Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industries, farmlands, and 10,000 homes. Peak mud extrusion rates of 180,000 m3/d were measured in the first few months of the eruption, which have decreased to <20,000 m3/d in 2012. Mud volcanoes often release fluids in a pulsating fashion, with periodic timescales ranging from minutes to days, and LUSI is no exception. These oscillations, common in natural systems of multi-phase fluid flow, are thought to result from some combination of complex feedback mechanisms between conduit and source geometry, fluid compressibility, viscosity and density, changes in lithostatic stresses, reservoir pressure, fluid phases or vent conditions. Crisis management workers and local residents reported observations of pulsating eruptive cycles lasting a few hours during the first two years of the eruption, and possibly beyond. Since that time, activity has shifted to individual transient eruptions recurring at intervals of a few minutes. In May and October of 2011, we documented the periodic explosive release of fluids at LUSI using a combination of high-resolution time-lapse photography, continuous webcam, open path FTIR, and thermal infrared imagery. The mud, consisting of approximately 70% water, is erupted at temperatures close to boiling. Gases are periodically released by the bursting of bubbles approximately 3 m in diameter, triggering mud fountains ~20 m in height. No appreciable gas seepage was detected in the quiescent intervals between bubble bursts. Absorption spectrometry in the infrared spectrum reveals that the gas released during explosions consists of 98.5% water vapor, 1% carbon dioxide, and 0.3% methane. On rare occasions, minor amounts of ammonia were also detected. Using simplified plume geometries based on observations, we estimate that LUSI releases approximately 1,500 T

  9. WATRE: a program for computing water and gas released from heated concrete

    SciTech Connect

    Claybrook, S.W.; Muhlestein, L.D.

    1985-01-01

    The WATRE computer program calculates the rate and quantity of water and carbon dioxide gas released from heated concrete. Recent development efforts have improved the numerical solution scheme, resulting in increased computational efficiency. The WATRE model is presented and the numerical procedure used to solve the governing equations is outlined. Validation of the WATRE model by comparison with extensive experimental data is emphasized. Results of a sensitivity study which investigated the effects that changes in input data have on WATRE calculations are also discussed.

  10. Modelling of fission gas release from irradiated UO2 fuel under high-temperature annealing conditions

    NASA Astrophysics Data System (ADS)

    Veshchunov, M. S.; Shestak, V. E.

    2012-11-01

    The new model for the vacancy field evolution in grains during annealing of irradiated fuel was developed and implemented in the MFPR code. The model simulates time and spatial variation of the vacancy concentration in the presence of extended vacancy sources (grain boundaries and dislocations) and sinks (growing intragranular bubbles). Being combined with the models for dislocation creep and for bubbles biased migration in the vacancy gradient, the new model self-consistently describes the processes of gas release and microstructure evolution observed in the annealing tests.

  11. Selective Recovery of Radioactive Carbon Dioxide Released from Nuclear Off-gas by Adsorption

    NASA Astrophysics Data System (ADS)

    Munakata, Kenzo; Koga, Akinori

    Off gases produced in the reprocessing of spent nuclear fuel contain various radioactive gases and emission of these gases to the environment must be suppressed as low as possible. 14C with a long half-life, which is mainly released as the form of carbon dioxide, is one of such gaseous radioactive materials. One of the measures to capture radioactive gases from the off-gas is the utilization of adsorption technique. In this work, the adsorption behavior of carbon dioxide on various adsorbents was studied. It was found that a MS4A (Molecular Sieve 4A) adsorbent is more suitable for selective recovery of carbon dioxide. Thus, more detailed adsorption characteristics of carbon dioxide were studied for a MS4A adsorbent. Moreover, the authors investigated the influence of coexistent water vapor, which is also contained in the off-gas, on the adsorption behavior of carbon dioxide.

  12. Releasing the trapped 1d Bose gas: from integrability and renormalization to Generalized Gibbs ensembles

    NASA Astrophysics Data System (ADS)

    Caux, Jean-Sébastien

    2013-05-01

    In this talk, we consider the out-of-equilibrium evolution of a one-dimensional bosonic gas (as described by the Lieb-Liniger model) after release from a parabolic trapping potential. We present a new method based on combining the theory of integrable models with numerical renormalization, which allows to reconstruct the post-quench dynamics of the gas all the way to infinite time. We also present a framework by which the generalized Gibbs ensemble, which has been suggested as the effective theory governing this dynamics, can be explicitly constructed. We compare predictions for reequilibration from this ensemble against the long-time dynamics observed using our method. Supported by FOM and NWO (Netherlands).

  13. Ocean circulation promotes methane release from gas hydrate outcrops at the NEPTUNE Canada Barkley Canyon node

    NASA Astrophysics Data System (ADS)

    Thomsen, Laurenz; Barnes, Christopher; Best, Mairi; Chapman, Ross; Pirenne, Benoît; Thomson, Richard; Vogt, Joachim

    2012-08-01

    The NEPTUNE Canada cabled observatory network enables non-destructive, controlled experiments and time-series observations with mobile robots on gas hydrates and benthic community structure on a small plateau of about 1 km2 at a water depth of 870 m in Barkley Canyon, about 100 km offshore Vancouver Island, British Columbia. A mobile Internet operated vehicle was used as an instrument platform to monitor and study up to 2000 m2 of sediment surface in real-time. In 2010 the first mission of the robot was to investigate the importance of oscillatory deep ocean currents on methane release at continental margins. Previously, other experimental studies have indicated that methane release from gas hydrate outcrops is diffusion-controlled and should be much higher than seepage from buried hydrate in semipermeable sediments. Our results show that periods of enhanced bottom currents associated with diurnal shelf waves, internal semidiurnal tides, and also wind-generated near-inertial motions can modulate methane seepage. Flow dependent destruction of gas hydrates within the hydrate stability field is possible from enhanced bottom currents when hydrates are not covered by either seafloor biota or sediments. The calculated seepage varied between 40-400 μmol CH4 m-2 s-1. This is 1-3 orders of magnitude higher than dissolution rates of buried hydrates through permeable sediments and well within the experimentally derived range for exposed gas hydrates under different hydrodynamic boundary conditions. We conclude that submarine canyons which display high hydrodynamic activity can become key areas of enhanced seepage as a result of emerging weather patterns due to climate change.

  14. Composition and flux of explosive gas release at LUSI mud volcano (East Java, Indonesia)

    NASA Astrophysics Data System (ADS)

    Vanderkluysen, Loïc; Burton, Michael R.; Clarke, Amanda B.; Hartnett, Hilairy E.; Smekens, Jean-François

    2014-07-01

    LUSI mud volcano has been erupting since May 2006 in the densely populated Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industry, farmland, and over 10,000 homes. Mud extrusion rates of 180,000 m3 d-1 were measured in the first few months of the eruption, decreasing to a loosely documented <20,000 m3 d-1 in 2012. The last few years of activity have been characterized by periodic short-lived eruptive bursts. In May and October 2011, we documented this activity using high-resolution time-lapse photography, open-path FTIR, and thermal infrared imagery. Gases (98% water vapor, 1.5% carbon dioxide, 0.5% methane) were periodically released by the bursting of bubbles approximately 3 m in diameter which triggered mud fountains to ˜10 m and gas plumes to hundreds of meters above the vent. During periods of quiescence (1-3 min), no appreciable gas seepage occurred. We estimate that LUSI releases approximately 2300 t yr-1 of methane, 30,000 t yr-1 of CO2, and 800,000 t yr-1 of water vapor. Gas bubble nucleation depths are >4000 m for methane and approximately 600 m for carbon dioxide; however, the mass fractions of these gases are insufficient to explain the observed dynamics. Rather, the primary driver of the cyclic bubble-bursting activity is decompressional boiling of water, which initiates a few tens of meters below the surface, setting up slug flow in the upper conduit. Our measured gas flux and conceptual model lead to a corresponding upper-bound estimate for the mud-water mass flux of 105 m3 d-1.

  15. Survival following accidental scarf strangulation.

    PubMed

    Shetty, Ullasa; Deepak, M; Hussain, Syed Ather; Usmani, Hadi; Osama, Muhammad; Pereira, Kiran Godwin; Menezes, Ritesh George

    2016-09-01

    Injury or death by strangulation, unless otherwise explained, is almost always homicidal. Accidental strangulation may occur but only very rarely. We present such a case of accidental strangulation and survival in a motorbike pillion rider. A long scarf (dupatta) clad woman, sitting at the back of a two wheeler motorbike, fell after her long scarf got caught in the back wheel. The lady was first taken to a local clinic and then later was referred to a hospital for a suspected spine injury where she made an uneventful recovery. This case report exposes the precarious position of women pillion riders wearing a long scarf and emphasizes the need for extra caution and the need for wheel guards on spoked wheels in particular. PMID:27048761

  16. The big chill: accidental hypothermia.

    PubMed

    Davis, Robert Allan

    2012-01-01

    A potential cause of such emergent issues as cardiac arrhythmias, hypotension, and fluid and electrolyte shifts, accidental hypothermia can be deadly, is common among trauma patients, and is often difficult to recognize. The author discusses predisposing conditions, the classic presentation, and the effects on normal thermoregulatory processes; explains how to conduct a systems assessment of the hypothermic patient; and describes crucial management strategies. PMID:22186703

  17. Measurement of fission gas release from irradiated U-Mo monolithic fuel samples

    NASA Astrophysics Data System (ADS)

    Burkes, Douglas E.; Casella, Amanda J.; Casella, Andrew M.; Luscher, Walter G.; Rice, Francine J.; Pool, Karl N.

    2015-06-01

    The uranium-molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world's highest power research reactors from the use of high enriched uranium (HEU) to low enriched uranium (LEU). One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the extent of fission product release from the fuel under anticipated service environments. An apparatus capable of heating post-irradiated small-scale samples cut from larger fuel segments according to specified thermal profiles under a controlled atmosphere has been installed into a hot cell. Results show that optimized experimental parameters to investigate fission product release from small samples have been established. Initial measurements conducted on aluminum alloy clad uranium-molybdenum monolithic fuel samples reveal three clear fission gas release events over the temperature range of 30-1000 °C. The mechanisms responsible for these events are discussed, and the results have been compared with available information in the literature.

  18. Species production and heat release rates in two-layered natural gas fires

    SciTech Connect

    Zukoski, E.E.; Morehart, J.H.; Kubota, T.; Toner, S.J. )

    1991-02-01

    A fire burning in an enclosure with restricted ventilation will result in the accumulation of a layer of warm products of combustion mixed with entrained air adjacent to the ceiling. For many conditions, the depth of this layer will extend to occupy a significant fraction of the volume of the room. Eventually, the interface between this vitiated ceiling layer and the uncontaminated environment below will position itself so that a large portion of the combustion processes occur in this vitiated layer. A description is given of experimental work concerning the rates of formation of product species and heat release in a turbulent, buoyant natural gas diffusion flame burning in this two-layered configuration. The enclosure was modeled by placing a hood above a burner so that it accumulated the plume gases, and the unsteady development of the ceiling layer was modeled by the direct addition of air into the upper portion of the hood. Measurements of the composition of these gases allowed the computation of stoichiometries and heat release rates. These investigations showed that the species produced in the flame depend primarily on the stoichiometry of the gases present in the ceiling layer and weakly on the temperature of the layer, but are independent of the fuel pair ratio of the mass transported into the layer by the plume. Heat release rates in the fires were compared to a theoretical limit based on a stoichiometric reaction of fuel and air with excess components left unchanged by the combustion.

  19. Measurement of fission gas release from irradiated U–Mo monolithic fuel samples

    SciTech Connect

    Burkes, Douglas E.; Casella, Amanda J.; Casella, Andrew M.; Luscher, Walter G.; Rice, Francine J.; Pool, Karl N.

    2015-06-01

    The uranium–molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world’s highest power research reactors from the use of high enriched uranium (HEU) to low enriched uranium (LEU). One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the extent of fission product release from the fuel under anticipated service environments. An apparatus capable of heating post-irradiated small-scale samples cut from larger fuel segments according to specified thermal profiles under a controlled atmosphere has been installed into a hot cell. Results show that optimized experimental parameters to investigate fission product release from small samples have been established. Initial measurements conducted on aluminum alloy clad uranium–molybdenum monolithic fuel samples reveal three clear fission gas release events over the temperature range of 30-1000 °C. The mechanisms responsible for these events are discussed, and the results have been compared with available information in the literature.

  20. Measurement of Fission Gas Release from Irradiated U-Mo Monolithic Fuel Samples

    SciTech Connect

    Burkes, Douglas; Casella, Amanda J.; Casella, Andrew M.; Luscher, Walter G.; Rice, Francine; Pool, Karl N.

    2015-06-01

    The uranium-molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world’s highest power research reactors from the use of high enriched uranium (HEU) to low enriched uranium (LEU). One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the extent of fission product release from the fuel under anticipated service environments. An apparatus capable of annealing post-irradiated small-scale samples cut from larger fuel segments according to specified thermal profiles under a controlled atmosphere has been installed into a hot cell. Results show that optimized experimental parameters to investigate fission product release from small samples have been established. Initial measurements conducted on aluminum alloy clad uranium-molybdenum monolithic fuel samples reveal three clear fission gas release events over the temperature range of 30-1050 C. The mechanisms responsible for these events are discussed, and the results have been compared with available information in literature.

  1. Chlorine gas release associated with employee language barrier--Arkansas, 2011.

    PubMed

    2012-12-01

    On June 27, 2011, a worker at a poultry processing plant in Arkansas began to pour sodium hypochlorite into a 55-gallon drum that contained residual acidic antimicrobial solution. When the sodium hypochlorite reacted with the solution, greenish-yellow chlorine gas was released into the small room where the drum was located and then spread into the plant, where approximately 600 workers were present. These workers promptly were evacuated. Chlorine is a respiratory irritant and can produce symptoms ranging from mild eye, nose, and throat irritation to severe inflammation of the lung, which can lead to death. Of the approximately 600 workers who were evacuated; 545 were later interviewed, 195 reported seeking medical treatment, 152 reported being hospitalized, and the plant nurse reported that five were admitted to intensive-care units. The next day, the Occupational Safety and Health Administration (OSHA) asked for technical assistance from CDC's National Institute for Occupational Safety and Health (NIOSH) to evaluate health effects of the release and make recommendations to prevent future occurrences. This report describes the results of that evaluation, including findings from two follow-up site visits conducted approximately 4 and 6 months after the release. Of the 545 workers who participated in the evaluation, three developed reactive airways dysfunction syndrome (RADS), an irritant-induced form of asthma that can persist for life. The worker who inadvertently mixed the two solutions indicated that the drum was labeled in English but he could only read Spanish. This incident underscores the danger posed by chlorine gas and the importance of employers providing adequate training and communication of health and safety precautions to employees. PMID:23222372

  2. Modeling Gas Transport in the Shallow Subsurface During the ZERT CO2 Release Test

    SciTech Connect

    Oldenburg, Curtis M.; Lewicki, Jennifer L.; Dobeck, Laura; Spangler, Lee

    2009-01-15

    We used the multiphase and multicomponent TOUGH2/EOS7CA model to carry out predictive simulations of CO{sub 2} injection into the shallow subsurface of an agricultural field in Bozeman, Montana. The purpose of the simulations was to inform the choice of CO{sub 2} injection rate and design of monitoring and detection activities for a CO{sub 2} release experiment. The release experiment configuration consists of a long horizontal well (70 m) installed at a depth of approximately 2.5 m into which CO{sub 2} is injected to mimic leakage from a geologic carbon sequestration site through a linear feature such as a fault. We estimated the permeability of the soil and cobble layers present at the site by manual inversion of measurements of soil CO{sub 2} flux from a vertical-well CO{sub 2} release. Based on these estimated permeability values, predictive simulations for the horizontal well showed that CO{sub 2} injection just below the water table creates an effective gas-flow pathway through the saturated zone up to the unsaturated zone. Once in the unsaturated zone, CO{sub 2} spreads out laterally within the cobble layer, where liquid saturation is relatively low. CO{sub 2} also migrates upward into the soil layer through the capillary barrier and seeps out at the ground surface. The simulations predicted a breakthrough time of approximately two days for the 100kg d{sup -1} injection rate, which also produced a flux within the range desired for testing detection and monitoring approaches. The seepage area produced by the model was approximately five meters wide above the horizontal well, compatible with the detection and monitoring methods tested. For a given flow rate, gas-phase diffusion of CO{sub 2} tends to dominate over advection near the ground surface, where the CO{sub 2} concentration gradient is large, while advection dominates deeper in the system.

  3. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 2. LLNL Annual Site-specific Data, 1953 - 2005

    SciTech Connect

    Peterson, S

    2007-08-15

    Historical information about tritium released routinely and accidentally from all Livermore Site Lawrence Livermore National Laboratory (LLNL) facilities and from the Tritium Research Laboratory of Sandia National Laboratories/California (SNL/CA) between 1953 through 2005 has been compiled and summarized in this report. Facility-specific data (annual release rates and dilution factors) have been derived from the historical information. These facility-specific data are needed to calculate annual doses to a hypothetical site-wide maximally exposed individual from routine releases of tritiated water (HTO) and tritiated hydrogen gas (HT) to the atmosphere. Doses can also be calculated from observed air tritium concentrations, and mean annual values for one air tritium sampling location are presented. Other historical data relevant to a dose reconstruction (e.g., meteorological data, including absolute humidity and rainfall) are also presented. Sources of information are carefully referenced, and assumptions are documented. Uncertainty distributions have been estimated for all parameter values. Confidence in data post-1974 is high.

  4. Effects of neutral gas release on current collection during the CHARGE-2 rocket experiment

    NASA Technical Reports Server (NTRS)

    Gilchrist, B. E.; Banks, P. M.; Neubert, T.; Williamson, P. R.; Myers, Neil B.; Raitt, W. John; Sasaki, S.

    1990-01-01

    Observations of current collection enhancements due to cold nitrogen gas control jet emissions from a highly charged rocket payload in the ionosphere are reported. These observations were made during the second cooperative high altitude rocket gun experiment (CHARGE-2) which was an electrically tethered mother/daughter payload system. The current collection enhancement was observed at the daughter payload located 100 to 400 m away from the mother which was firing an energetic electron beam. The authors interpret these results in terms of an electrical discharge forming in close proximity to the daughter during the short periods of gas emission. The results indicate that it is possible to enhance the electron current collection capability of positively charged vehicles by means of deliberate neutral gas releases into an otherwise undisturbed space plasma. These results can also be compared with recent laboratory observations of hollow cathode plasma contactors operating in the ignited mode. Experimental observations of current collection enhancements due to cold nitrogen gas control jet emissions from a highly charged, isolated daughter payload in the nighttime ionosphere were made. These observations were derived from the second cooperative high altitude rocket gun experiment (CHARGE-2) which was an electrically tethered mother-daughter payload system. The rocket flew from White Sands Missile Range (WSMR) in December, 1985. The rocket achieved an altitude of 261 km and carried a 1 keV electron beam emitting up to 48 mA of current (Myers, et al., 1989a). The mother payload, carried the electron beam source, while the daughter acted as a remote current collection and observation platform and reached a distance of 426 m away from the main payload. Gas emissions at the daughter were due to periodic thruster jet firings to maintain separation velocity between the two payloads.

  5. Strong-Sludge Gas Retention and Release Mechanisms in Clay Simulants

    SciTech Connect

    Gauglitz, Phillip A.; Buchmiller, William C.; Probert, Samuel G.; Owen, Antionette T.; Brockman, Fred J.

    2012-02-24

    The Hanford Site has 28 double-shell tanks (DSTs) and 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. The mission of the Department of Energy's River Protection Project is to retrieve and treat the Hanford tank waste for disposal and close the tank farms. A key aspect of the mission is to retrieve and transfer waste from the SSTs, which are at greater risk for leaking, into DSTs for interim storage until the waste is transferred to and treated in the Waste Treatment and Immobilization Plant. There is, however, limited space in the existing DSTs to accept waste transfers from the SSTs, and approaches to overcoming the limited DST space will benefit the overall mission. The purpose of this study is to summarize and analyze the key previous experiment that forms the basis for the relaxed controls and to summarize progress and results on new experiments focused on understanding the conditions that result in low gas retention. The previous large-scale test used about 50 m3 of sediment, which would be unwieldy for doing multiple parametric experiments. Accordingly, experiments began with smaller-scale tests to determine whether the desired mechanisms can be studied without the difficulty of conducting very large experiments. The most significant results from the current experiments are that progressively lower gas retention occurs in tests with progressively deeper sediment layers and that the method of gas generation also affects the maximum retention. Based on the results of this study, it is plausible that relatively low gas retention could occur in sufficiently deep tank waste in DSTs. The current studies and previous work, however, have not explored how gas retention and release will behave when two or more layers with different properties are present.

  6. Diagenetic Features in Yellowknife Bay, Gale Crater, Mars: Implications for Substrate Rheology and Potential Gas Release

    NASA Technical Reports Server (NTRS)

    Kah, L. C.; Stack, K; Siebach, K.; Grotzinger, J.; Summer, D.; Farien, A.; Oehler, D.; Schieber, J.; Leville, R.; Edgar, L; Rice, M.

    2014-01-01

    Multiple diagenetic features have been observed in clay­-bearing mudstone exposed within Yellowknife Bay, Gale Crater, Mars. These features occurred during at least two separate episodes: an early generation of spheroidal concretions that co-­occur with a dense networks of mineralized fractures, and a later generation of mineralized veins. Concretions consist of mm-sized spheroids (0.4 to 8.0 mm, mean diameter of 1.2 mm) that are distinctly more resistant than the encompassing mudstone. Dissected spheroids suggest an origin via compaction and incipient lithification of the substrate at the perimeter of syndepositional void space. Concretions are generally patchy in their distribution within clay--bearing mudstone, but in places can be the dominant fabric element. Locally dense networks of mineralized fractures occur in regions of low concretion abundance. These consist of short (< 50 cm), curvilinear to planar mineralized voids that occur across a range of orientations from vertical to subhorizontal. Fractures are filled by multi-phase cement consisting of two isopachous, erosionally resistant outer bands, and a central less resistant fill. Physical relationships suggests that original fractures may have formed as both interconnected voids and as discrete cross--cutting features. Co--occurrence of early diagenetic concretions and fracture networks suggests a common origin via gas release within a subaqueous, shallow substrate. We suggest that gas release within weakly cohesive subsurface sediments resulted in substrate dewatering and an increase in the cohesive strength of the substrate. Local differences in substrate strength and rate of gas production would have result in formation of either discrete voids or fracture networks. A second generation of mineralized veins is characterized by a regionally low spatial density, predominantly vertical or horizontal orientations, and a single phase of Ca--sulfate mineral fill. These veins cross-cut the early diagenetic

  7. Dehydration kinetics and thermochemistry of selected hydrous phases, and simulated gas release pattern in carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Bose, Kunal; Ganguly, J.

    1992-01-01

    As part of our continued program of study on the volatile bearing phases and volatile resource potential of carbonaceous chondrite, results of our experimental studies on the dehydration kinetics of talc as a function of temperature and grain size (50 to 0.5 microns), equilibrium dehydration boundary of talc to 40 kbars, calorimetric study of enthalpy of formation of both natural and synthetic talc as a function of grain size, and preliminary results on the dehydration kinetics of epsomite are reported. In addition, theoretical calculations on the gas release pattern of Murchison meteorite, which is a C2(CM) carbonaceous chondrite, were performed. The kinetic study of talc leads to a dehydration rate constant for 40-50 microns size fraction of k = (3.23 x 10(exp 4))exp(-Q/RT)/min with the activation energy Q = 376 (plus or minus 20) kJ/mole. The dehydration rate was found to increase somewhat with decreasing grain size. The enthalpy of formation of talc from elements was measured to be -5896(10) kJ/mol. There was no measurable effect of grain size on the enthalpy beyond the limits of precision of the calorimetric studies. Also the calorimetric enthalpy of both synthetic and natural talc was found to be essentially the same, within the precision of measurements, although the natural talc had a slightly larger field of stability in our phase equilibrium studies. The high pressure experimental data the dehydration equilibrium of talc (talc = enstatite + coesite + H2O) is in strong disagreement with that calculated from the available thermochemical data, which were constrained to fit the low pressure experimental results. The calculated gas release pattern of Murchison meteorite were in reasonable agreement with that determined by stepwise heating in a gas chromatograph.

  8. Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

    SciTech Connect

    Rassat, S.D.; Gauglitz, P.A.; Bredt, P.R.; Mahoney, L.A.; Forbes, S.V.; Tingey, S.M.

    1997-09-01

    The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the safe storage of Hanford tank wastes. To this end, we strive to develop an understanding of the mechanisms of flammable gas retention and release in Hanford tanks through laboratory investigations on actual tank wastes. These results support the closure of the Flammable Gas Unreviewed Safety Question (USQ) on the safe storage of waste tanks known to retain flammable gases and support resolution of the broader Flammable Gas Safety Issue. The overall purpose of this ongoing study is to develop a comprehensive and thorough understanding of the mechanisms of flammable gas retention and release. The first objective of the current study was to classify bubble retention and release mechanisms in two previously untested waste materials from Tanks 241-AN-103 (AN-103) and 241-AW-101 (AW-101). Results were obtained for retention mechanisms, release characteristics, and the maximum gas retention. In addition, unique behavior was also documented and compared with previously studied waste samples. The second objective was to lengthen the duration of the experiments to evaluate the role of slowing bubble growth on the retention and release behavior. Results were obtained for experiments lasting from a few hours to a few days.

  9. Time-normalized correlation function of ultracold atomic gas released from an optical lattice

    SciTech Connect

    Li Yan; Chen Lisheng; Xiong Hongwei

    2007-12-15

    The time-correlation function of ultracold atomic gas is theoretically investigated. Atoms are initially confined in an optical lattice and in a Mott insulator regime. We consider the effect of gravity on the time correlation among atomic wave functions when the atomic cloud is released from the optical lattice. The time-correlation function in this process displays sharp peaks, a feature that is analogous to the spatial-normalized correlation observed in recent experiments. The origin and properties of the interference pattern are theoretically investigated in detail. Similar to the spatial correlation, the time correlation in expanding atomic clouds reveals the ordering of indistinguishable particles in an optical lattice. Experimental detection scheme and its potential use in the measurement of gravitational acceleration are briefly discussed.

  10. Modeling dispersion from toxic gas released after a train collision in Graniteville, SC.

    PubMed

    Buckley, Robert L; Hunter, Charles H; Addis, Robert P; Parker, Matthew J

    2007-03-01

    The Savannah River National Laboratory (SRNL) Weather Information and Display System was used to provide meteorological and atmospheric modeling/consequence assessment support to state and local agencies after the collision of two Norfolk Southern freight trains on the morning of January 6, 2005. This collision resulted in the release of several toxic chemicals to the environment, including chlorine. The dense and highly toxic cloud of chlorine gas that formed in the vicinity of the accident was responsible for 9 fatalities and caused injuries to more than 500 others. Transport model results depicting the forecast path of the ongoing release were made available to emergency managers in the county's Unified Command Center shortly after SRNL received a request for assistance. Support continued over the ensuing 2 days of the active response. The SRNL also provided weather briefings and transport/consequence assessment model results to responders from the South Carolina Department of Health and Environmental Control, the Savannah River Site (SRS) Emergency Operations Center, Department of Energy headquarters, and hazard material teams dispatched from the SRS. Operational model-generated forecast winds used in consequence assessments conducted during the incident were provided at 2-km horizontal grid spacing during the accident response. High-resolution Regional Atmospheric Modeling System (RAMS, version 4.3.0) simulation was later performed to examine potential influences of local topography on plume migration in greater detail. The detailed RAMS simulation was used to determine meteorology using multiple grids with an innermost grid spacing of 125 m. Results from the two simulations are shown to generally agree with meteorological observations at the time; consequently, local topography did not significantly affect wind in the area. Use of a dense gas dispersion model to simulate localized plume behavior using the higher-resolution winds indicated agreement with

  11. Challenges and methodology for safety analysis of a high-level waste tank with large periodic releases of flammable gas

    SciTech Connect

    Edwards, J.N.; Pasamehmetoglu, K.O.; White, J.R.; Stewart, C.W.

    1994-07-01

    Tank 241-SY-101, located at the Department of Energy Hanford Site, has periodically released up to 10,000 ft{sup 3} of flammable gas. This release has been one of the highest-priority DOE operational safety problems. The gases include hydrogen and ammonia (fuels) and nitrous oxide (oxidizer). There have been many opinions regarding the controlling mechanisms for these releases, but demonstrating an adequate understanding of the problem, selecting a mitigation methodology, and preparing the safety analysis have presented numerous new challenges. The mitigation method selected for the tank was to install a pump that would mix the tank contents and eliminate the sludge layer believed to be responsible for the gas retention and periodic releases. This report will describe the principal analysis methodologies used to prepare the safety assessment for the installation and operation of the pump, and because this activity has been completed, it will describe the results of pump operation.

  12. Isotopic noble gas signatures released from medical isotope production facilities--simulations and measurements.

    PubMed

    Saey, Paul R J; Bowyer, Theodore W; Ringbom, Anders

    2010-09-01

    Radioxenon isotopes play a major role in confirming whether or not an underground explosion was nuclear in nature. It is then of key importance to understand the sources of environmental radioxenon to be able to distinguish civil sources from those of a nuclear explosion. Based on several years of measurements, combined with advanced atmospheric transport model results, it was recently shown that the main source of radioxenon observations are strong and regular batch releases from a very limited number of medical isotope production facilities. This paper reviews production processes in different medical isotope facilities during which radioxenon is produced. Radioxenon activity concentrations and isotopic compositions are calculated for six large facilities. The results are compared with calculated signals from nuclear explosions. Further, the outcome is compared and found to be consistent with radioxenon measurements recently performed in and around three of these facilities. Some anomalies in measurements in which (131m)Xe was detected were found and a possible explanation is proposed. It was also calculated that the dose rate of the releases is well below regulatory values. Based on these results, it should be possible to better understand, interpret and verify signals measured in the noble gas measurement systems in the International Monitoring of the Comprehensive Nuclear-Test-Ban Treaty. PMID:20447828

  13. Isotopic noble gas signatures released from medical isotope production facilities - Simulations and measurements

    SciTech Connect

    Saey, Paul R.; Bowyer, Ted W.; Ringbom, Anders

    2010-09-09

    Journal article on the role that radioxenon isotopes play in confirming whether or not an underground explosion was nuclear in nature. Radioxenon isotopes play a major role in confirming whether or not an underground explosion was nuclear in nature. It is then of key importance to understand the sources of environmental radioxenon to be able to distinguish civil sources from those of a nuclear explosion. Based on several years of measurements, combined with advanced atmospheric transport model results, it was recently shown that the main source of radioxenon observations are strong and regular batch releases from a very limited number of medical isotope production facilities. This paper reviews production processes in different medical isotope facilities during which radioxenon is produced. Radioxenon activity concentrations and isotopic compositions are calculated for six large facilities. The results are compared with calculated signals from nuclear explosions. Further, the outcome is compared and found to be consistent with radioxenon measurements recently performed in and around three of these facilities. Some anomalies in measurements in which {sup 131m}Xe was detected were found and a possible explanation is proposed. It was also calculated that the dose rate of the releases is well below regulatory values. Based on these results, it should be possible to better understand, interpret and verify signals measured in the noble gas measurement systems in the International Monitoring of the Comprehensive Nuclear-Test-Ban Treaty.

  14. Rapid aqueous release of fission products from high burn-up LWR fuel: Experimental results and correlations with fission gas release

    NASA Astrophysics Data System (ADS)

    Johnson, L.; Günther-Leopold, I.; Kobler Waldis, J.; Linder, H. P.; Low, J.; Cui, D.; Ekeroth, E.; Spahiu, K.; Evins, L. Z.

    2012-01-01

    Studies of the rapid aqueous release of fission products from UO 2 and MOX fuel are of interest for the assessment of the safety of geological disposal of spent fuel, because of the associated potential contribution to dose in radiological safety assessment. Studies have shown that correlations between fission gas release (FGR) and the fraction rapidly leached of various long-lived fission products can provide a useful method to obtain some of this information. Previously, these studies have been limited largely to fuel with burn-up values below 50 MWd/kg U. Collaborative studies involving SKB, Studsvik, Nagra and PSI have provided new data on short-term release of 137Cs and 129I for a number of fuels irradiated to burn-ups of 50-75 MWd/kgU. In addition a method for analysis of leaching solutions for 79Se was developed. The results of the studies show that the fractional release of 137Cs is usually much lower than the FGR covering the entire range of burn-ups studied. Fractional 129I releases are somewhat larger, but only in cases in which the fuel was forcibly extracted from the cladding. Despite the expected high degree of segregation of fission gas (and by association 137Cs and 129I) in the high burn-up rim, no evidence was found for a significant contribution to release from the rim region. The method for 79Se analysis developed did not permit its detection. Nonetheless, based on the detection limit, the results suggest that 79Se is not preferentially leached from spent fuel.

  15. Antimicrobial activity of controlled-release chlorine dioxide gas on fresh blueberries.

    PubMed

    Sun, Xiuxiu; Bai, Jinhe; Ference, Christopher; Wang, Zhe; Zhang, Yifan; Narciso, Jan; Zhou, Kequan

    2014-07-01

    The effect of chlorine dioxide (ClO2) gas on the safety and quality of blueberries was studied. In vitro studies revealed that both ClO2 gas fumigation and ClO2 direct contact in water killed food pathogen bacterium Escherichia coli and fruit decay pathogen fungus Colletotrichum acutatum. In vivo studies were conducted using noninoculated berries and berries inoculated with postharvest decay and foodborne pathogens. Berries were inoculated with either E. coli (5.2 log CFU/g) or C. acutatum (3.9 log CFU/g). Inoculated fruit were dried for 2 h at room temperature in a climate-controlled laboratory and packed in perforated commercial clamshells, with or without ClO2 pads, and stored at 10°C for up to 9 days. The effects of ClO2 on microbial populations and fruit firmness were monitored during storage. In the inoculation experiment, treatment with ClO2 reduced populations of E. coli and C. acutatum by 2.2 to 3.3 and 1.3 to 2.0 log CFU/g, respectively. For the noninoculated blueberries, the initial total aerobic bacteria count and the yeast and mold count were 4.2 and 4.1 log CFU/g, respectively. ClO2 treatment reduced total aerobic bacteria count and yeast and mold count by 1.5 to 1.8 and 1.3 to 1.7 log CFU/g, respectively. The firmness of both inoculated and noninoculated blueberries was maintained by ClO2 treatment. Thus, controlled-release ClO2 gas fumigation technology shows promise as an effective and practical antimicrobial agent in commercial clamshell packaging of blueberry and other fruits. PMID:24988018

  16. An analytical study of volatile metallic fission product release from very high temperature gas-cooled reactor fuel and core

    SciTech Connect

    Mitake, S.; Okamoto, F.

    1988-04-01

    Release characteristics of volatile metallic fission products from the coated fuel particle and the reactor core for a very high temperature gas-cooled reactor during its power operation has been studied using numerical analysis. A computer code FORNAX, based on Fick's diffusion law and the evaporation mass transfer relation, has been developed, which considers, in particular, distribution and time histories of power density, fuel temperature, and failed and degraded fuel particle fractions in the core. Applicability of the code to evaluate the core design has been shown and the following have been indicated on the release of cesium from the reactor: 1. The release from the intact fuel particles by diffusion through their intact coatings shows larger contribution in the total core release at higher temperature. 2. The diffusion release from the intact particle is governed not only by the diffusion in the silicon carbide layer but also by that in the fuel kernel.

  17. Accidental inflation in the landscape

    SciTech Connect

    Blanco-Pillado, Jose J.; Metallinos, Konstantinos; Gomez-Reino, Marta E-mail: marta.gomez-reino.perez@cern.ch

    2013-02-01

    We study some aspects of fine tuning in inflationary scenarios within string theory flux compactifications and, in particular, in models of accidental inflation. We investigate the possibility that the apparent fine-tuning of the low energy parameters of the theory needed to have inflation can be generically obtained by scanning the values of the fluxes over the landscape. Furthermore, we find that the existence of a landscape of eternal inflation in this model provides us with a natural theory of initial conditions for the inflationary period in our vacuum. We demonstrate how these two effects work in a small corner of the landscape associated with the complex structure of the Calabi-Yau manifold P{sup 4}{sub [1,1,1,6,9]} by numerically investigating the flux vacua of a reduced moduli space. This allows us to obtain the distribution of observable parameters for inflation in this mini-landscape directly from the fluxes.

  18. Is the tribimaximal mixing accidental?

    SciTech Connect

    Abbas, Mohammed; Smirnov, A. Yu.

    2010-07-01

    The tribimaximal (TBM) mixing is not accidental if structures of the corresponding leptonic mass matrices follow immediately from certain (residual or broken) flavor symmetry. We develop a simple formalism which allows one to analyze effects of deviations of the lepton mixing from TBM on the structure of the neutrino mass matrix and on the underlying flavor symmetry. We show that possible deviations from the TBM mixing can lead to strong modifications of the mass matrix and strong violation of the TBM-mass relations. As a result, the mass matrix may have an 'anarchical' structure with random values of elements or it may have some symmetry that differs from the TBM symmetry. Interesting examples include matrices with texture zeros, matrices with certain 'flavor alignment' as well as hierarchical matrices with a two-component structure, where the dominant and subdominant contributions have different symmetries. This opens up new approaches to understanding the lepton mixing.

  19. Twenty Years of Continuous gas Release at Kilauea: Effusive Lessons in a Volatile Time

    NASA Astrophysics Data System (ADS)

    Sutton, A. J.; Elias, T.

    2002-12-01

    The observatory worker who has lived a quarter of a century with Hawaiian lavas frothing in action, cannot fail to realize that gas chemistry is the heart of the volcano magma problem. T.A. Jaggar, 1940 Kilauea's Pu`u `O`o-Kupaianaha eruption has presented workers with a nearly ideal setting to develop and test models of how this volcano and others like it work, from the viewpoint of magma transport, gas release, and eruption dynamics. Gas sampling studies, and in-situ and remote emission measurements can be conducted more easily at Kilauea than at other volcanoes because of its approachable nature and because of advances in instrumentation and analytical techniques. Analyses of gases from the eruption and from early in the last century have, with studies of volatiles trapped in submarine lavas, been used to conceptualize a degassing model for Kilauea concordant with contemporaneous geologic and geophysical evidence delineating the volcano's internal structure. More recent studies have revealed a greater CO2 emission rate than previously thought. The revised estimates have been used to infer changes in magma supply rate. Meanwhile, SO2 emission rates and our improved knowledge of residual volatiles are being used in parallel with geophysical methods, to monitor the eruption rate. Continuous monitoring studies using on-site species-selective sensors are a rapidly evolving part of the gas studies effort for the eruption. The Pu`u `O`o-Kupaianaha eruption has also provided an opportunity to study hazards associated with long-term environmental effects of volcanic emissions. Beginning in mid-1986, when activity changed from episodic fountaining to continuous effusion, volcanic air pollution, known locally as vog, became an unfortunate part of everyday life for Hawai`i residents and visitors. Since then, Kilauea has on average released about 1,600 tonnes of SO2 per day, roughly 6,000 times the daily amount judged by the EPA to classify an emitter as a major industrial

  20. Health Effects of Cut Gas Lines and Other Petroleum Product Release Incidents - Seven States, 2010-2012.

    PubMed

    Anderson, Ayana R

    2015-06-12

    Large mass casualty gas explosions and catastrophic oil spills are widely reported and receive considerable regulatory attention. Smaller, less catastrophic petroleum product releases are less likely to receive publicity, although study of these incidents might help focus and prioritize prevention efforts. To describe the causes and health impacts of petroleum product release incidents (including gas explosions and oil spills), the Agency for Toxic Substances and Disease Registry (ATSDR) analyzed 2010-2012 data from the National Toxic Substance Incidents Program (NTSIP). A total of 1,369 petroleum product release incidents were reported from seven states, resulting in 512 injuries and 36 deaths. Approximately one fourth of the incidents were associated with utilities, and approximately one fifth were associated with private vehicles or residences. Approximately 10% of petroleum product releases resulted from inadvertent damage to utility lines. Understanding the characteristics of acute petroleum product releases can aid the public and utility workers in the development of preventive strategies and reduce the morbidity and mortality associated with such releases. PMID:26068562

  1. Fuel failure and fission gas release in high burnup PWR fuels under RIA conditions

    NASA Astrophysics Data System (ADS)

    Fuketa, Toyoshi; Sasajima, Hideo; Mori, Yukihide; Ishijima, Kiyomi

    1997-09-01

    To study the fuel behavior and to evaluate the fuel enthalpy threshold of fuel rod failure under reactivity initiated accident (RIA) conditions, a series of experiments using pulse irradiation capability of the Nuclear Safety Research Reactor (NSRR) has been performed. During the experiments with 50 MWd/kg U PWR fuel rods (HBO test series; an acronym for high burnup fuels irradiated in Ohi unit 1 reactor), significant cladding failure occurred. The energy deposition level at the instant of the fuel failure in the test is 60 cal/g fuel, and is considerably lower than those expected and pre-evaluated. The result suggests that mechanical interaction between the fuel pellets and the cladding tube with decreased integrity due to hydrogen embrittlement causes fuel failure at the low energy deposition level. After the pulse irradiation, the fuel pellets were found as fragmented debris in the coolant water, and most of these were finely fragmented. This paper describes several key observations in the NSRR experiments, which include cladding failure at the lower enthalpy level, possible post-failure events and large fission gas release.

  2. On-site gamma-ray spectroscopic measurements of fission gas release in irradiated nuclear fuel.

    PubMed

    Matsson, I; Grapengiesser, B; Andersson, B

    2007-01-01

    An experimental, non-destructive in-pool, method for measuring fission gas release (FGR) in irradiated nuclear fuel has been developed. Using the method, a significant number of experiments have been performed in-pool at several nuclear power plants of the BWR type. The method utilises the 514 keV gamma-radiation from the gaseous fission product (85)Kr captured in the fuel rod plenum volume. A submergible measuring device (LOKET) consisting of an HPGe-detector and a collimator system was utilised allowing for single rod measurements on virtually all types of BWR fuel. A FGR database covering a wide range of burn-ups (up to average rod burn-up well above 60 MWd/kgU), irradiation history, fuel rod position in cross section and fuel designs has been compiled and used for computer code benchmarking, fuel performance analysis and feedback to reactor operators. Measurements clearly indicate the low FGR in more modern fuel designs in comparison to older fuel types. PMID:16949295

  3. STEADY STATE FLAMMABLE GAS RELEASE RATE CALCULATION AND LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE

    SciTech Connect

    MEACHAM JE

    2008-11-17

    This report assesses the steady state flammability level under off normal ventilation conditions in the tank headspace for 28 double-shell tanks (DST) and 149 single shell-tanks (SST) at the Hanford Site. Flammability was calculated using estimated gas release rates, Le Chatelier's rule, and lower flammability limits of fuels in an air mixture. This revision updates the hydrogen generation rate input data for al1 177 tanks using waste composition information from the Best Basis Inventory Detail Report (data effective as of August 4,2008). Assuming only barometric breathing, the shortest time to reach 25% of the lower flammability limit is 13 days for DSTs (i.e., tank 241-AZ-102) and 36 days for SSTs (i.e., tank 241-B-203). Assuming zero ventilation, the shortest time to reach 25% of the lower flammability limit is 12 days for DSTs (i.e., tank 241-AZ-102) and 34 days for SSTs (i.e., tank 241-B-203).

  4. STEADY STATE FLAMMABLE GAS RELEASE RATE CALCULATION AND LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE

    SciTech Connect

    MEACHAM JE

    2009-10-26

    This report assesses the steady state flammability level under off normal ventilation conditions in the tank headspace for 28 double-shell tanks (DST) and 149 single shell-tanks (SST) at the Hanford Site. Flammability was calculated using estimated gas release rates, Le Chatelier's rule, and lower flammability limits of fuels in an air mixture. This revision updates the hydrogen generation rate input data for all 177 tanks using waste composition information from the Best Basis Inventory Detail Report (data effective as of August 4,2008). Assuming only barometric breathing, the shortest time to reach 25% of the lower flammability limit is 11 days for DSTs (i.e., tank 241-AZ-10l) and 36 days for SSTs (i.e., tank 241-B-203). Assuming zero ventilation, the shortest time to reach 25% of the lower flammability limit is 10 days for DSTs (i.e., tank 241-AZ-101) and 34 days for SSTs (i.e., tank 241-B-203).

  5. Small scale controls of greenhouse gas release under elevated N deposition rates in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-06-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain nitrous oxide release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  6. Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill

    PubMed Central

    Reddy, Christopher M.; Arey, J. Samuel; Seewald, Jeffrey S.; Sylva, Sean P.; Lemkau, Karin L.; Nelson, Robert K.; Carmichael, Catherine A.; McIntyre, Cameron P.; Fenwick, Judith; Ventura, G. Todd; Van Mooy, Benjamin A. S.; Camilli, Richard

    2012-01-01

    Quantitative information regarding the endmember composition of the gas and oil that flowed from the Macondo well during the Deepwater Horizon oil spill is essential for determining the oil flow rate, total oil volume released, and trajectories and fates of hydrocarbon components in the marine environment. Using isobaric gas-tight samplers, we collected discrete samples directly above the Macondo well on June 21, 2010, and analyzed the gas and oil. We found that the fluids flowing from the Macondo well had a gas-to-oil ratio of 1,600 standard cubic feet per petroleum barrel. Based on the measured endmember gas-to-oil ratio and the Federally estimated net liquid oil release of 4.1 million barrels, the total amount of C1-C5 hydrocarbons released to the water column was 1.7 × 1011 g. The endmember gas and oil compositions then enabled us to study the fractionation of petroleum hydrocarbons in discrete water samples collected in June 2010 within a southwest trending hydrocarbon-enriched plume of neutrally buoyant water at a water depth of 1,100 m. The most abundant petroleum hydrocarbons larger than C1-C5 were benzene, toluene, ethylbenzene, and total xylenes at concentrations up to 78 μg L-1. Comparison of the endmember gas and oil composition with the composition of water column samples showed that the plume was preferentially enriched with water-soluble components, indicating that aqueous dissolution played a major role in plume formation, whereas the fates of relatively insoluble petroleum components were initially controlled by other processes. PMID:21768331

  7. Use of an accelerometer and a microphone as gas detectors in the online quantitative detection of hydrogen released from ammonia borane by gas chromatography.

    PubMed

    He, Yi-San; Chen, Kuan-Fu; Lin, Chien-Hung; Lin, Min-Tsung; Chen, Chien-Chung; Lin, Cheng-Huang

    2013-03-19

    The use of an accelerometer as a gas detector in gas chromatography (GC) is described for the first time. A milli-whistle was connected to the outlet of the GC capillary. When the eluted and GC carrier gases pass through the capillary and milli-whistle, a sound is produced. After a fast Fourier transform (FFT), the sound wave generated from the milli-whistle is picked up by a microphone and the resulting vibration of the milli-whistle body can be recorded by an accelerometer. The release of hydrogen gas, as the result of thermal energy, from ammonia borane (NH3BH3), which has been suggested as a storage medium for hydrogen, was selected as the model sample. The findings show that the frequencies generated, either by sound or by the vibration from the whistle body, were identical. The concentration levels of the released hydrogen gas can be determined online, based on the frequency changes. Ammonia borane was placed in a brass reservoir, heated continually, and the released hydrogen gas was directly injected into the GC inlet at 0.5 min intervals, using a home-built electromagnetic pulse injector. The concentration of hydrogen for each injection can be calculated immediately. When the ammonia borane was encapsulated within a polycarbonate (PC) microtube array membrane, the temperature required for the release of hydrogen can be decreased, which would make such a material more convenient for use. The findings indicate that 1.0 mg of ammonia borane can produce hydrogen in the range of 1.0-1.25 mL, in the temperature range of 85-115 °C. PMID:23419032

  8. The characterization and evaluation of accidental explosions

    NASA Technical Reports Server (NTRS)

    Strehlow, R. A.; Baker, W. E.

    1975-01-01

    Accidental explosions are discussed from a number of viewpoints. First, all accidental explosions, intentional explosions and natural explosions are characterized by type. Second, the nature of the blast wave produced by an ideal (point source or HE) explosion is discussed to form a basis for describing how other explosion processes yield deviations from ideal blast wave behavior. The current status blast damage mechanism evaluation is also discussed. Third, the current status of our understanding of each different category of accidental explosions is discussed in some detail.

  9. Accidental death involving professional fireworks.

    PubMed

    Romolo, Francesco Saverio; Aromatario, Mariarosaria; Bottoni, Edoardo; Cappelletti, Simone; Fiore, Paola Antonella; Ciallella, Costantino

    2014-01-01

    An interesting case of accidental death involving the explosion of professional fireworks in an apartment is described. The examination of the scene permitted to study several effects of the explosion on walls, ceiling, furniture and especially on a balcony where the victim was found. The external examination of the victim showed extensive thermal injuries, degloving injuries and extensive shrapnel wounds. The autopsy examination showed subarachnoid haemorrhage localized to the cerebellum, haemorrhage in the soft tissues of the neck and chest and fracture of one clavicle. Almost the entire surface of lungs showed blunt injuries and the liver showed tearing of parenchyma and multiple cavities. Histological analysis were carried out showing thickening of alveolar septae, enlargement of alveolar spaces and alveolar ruptures in lung sections while numerous, round, empty spaces were detected in the parenchyma of the liver. The examination of the scene and of the fragments found showed that at least eight pyrotechnical charges exploded on the balcony, in close proximity of the threshold with the living room of the apartment. According to the chemical findings, the charges were typical for professional use and were filled with a mixture of potassium perchlorate and aluminium. A conservative calculation results in more than 1.5 kg total mass of pyrotechnic composition exploding very close to the victim. PMID:24279979

  10. Accidental Bolus of Parenteral Nutrition.

    PubMed

    Lodeserto, Frank; Al-Jaghbeer, Mohammed; Huang, David

    2016-08-01

    There is a paucity of data that exists regarding acute toxicity and management in the setting of parental nutrition (PN) overdose. We describe a case of a patient who received an accidental rapid bolus of PN and fat emulsion. She developed a seizure, metabolic acidosis, arrhythmias, myocardial ischemia, altered mental status, hypotension, and hypoxemia likely caused by elevated triglycerides, leading to a hyperviscosity syndrome. After failing standard therapy, she was successfully treated with a single-volume plasma exchange with resolution of symptoms. Fat emulsion or intravenous lipid emulsion and much of its safety have been recently described in its use as a rescue therapy in resuscitation from drug-related toxicity. Elevated serum triglyceride levels can result in a picture similar to a hyperviscosity syndrome. Plasma exchange is a known therapeutic modality for the management of hyperviscosity syndrome and a novel therapy in the treatment of hyperviscosity syndrome due to fat emulsion therapy. In a patient receiving PN with development of rapid deterioration of clinical status, without an obvious etiology, there should be consideration of PN overdose. A rapid assessment and treatment of severe electrolyte abnormalities should be undertaken immediately to prevent life-threatening cardiovascular and central nervous system collapse. If fat emulsion was rapidly coadministered and there are signs and symptoms of hyperviscosity syndrome, then consideration should be given to plasma exchange as an effective therapeutic treatment option. PMID:25666023

  11. The Effelsberg-Bonn H i Survey: Milky Way gas. First data release

    NASA Astrophysics Data System (ADS)

    Winkel, B.; Kerp, J.; Flöer, L.; Kalberla, P. M. W.; Ben Bekhti, N.; Keller, R.; Lenz, D.

    2016-01-01

    Context. The Effelsberg-Bonn H i Survey (EBHIS) is a new 21-cm survey performed with the 100-m telescope at Effelsberg. It covers the whole northern sky out to a redshift of z ~ 0.07 and comprises H i line emission from the Milky Way and the Local Volume. Aims: We aim to substitute the northern-hemisphere part of the Leiden/Argentine/Bonn Milky Way H i survey (LAB) with this first EBHIS data release, which presents the H i gas in the Milky Way regime. Methods: The use of a seven-beam L-band array made it feasible to perform this all-sky survey with a 100-m class telescope in a reasonable amount of observing time. State-of-the-art fast-Fourier-transform spectrometers provide the necessary data read-out speed, dynamic range, and spectral resolution to apply software radio-frequency interference mitigation. EBHIS is corrected for stray radiation and employs frequency-dependent flux-density calibration and sophisticated baseline-removal techniques to ensure the highest possible data quality. Results: Detailed analyses of the resulting data products show that EBHIS is not only outperforming LAB in terms of sensitivity and angular resolution, but also matches the intensity-scale of LAB extremely well, allowing EBHIS to be used as a drop-in replacement for LAB. Data products are made available to the public in a variety of forms. Most important, we provide a properly gridded Milky Way H i column density map in HEALPix representation. To maximize the usefulness of EBHIS data, we estimate uncertainties in the H i column density and brightness temperature distributions, accounting for systematic effects. EBHIS Milky Way HI data is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/585/A41

  12. An accidental poisoning with mitragynine.

    PubMed

    Karinen, Ritva; Fosen, Jan Toralf; Rogde, Sidsel; Vindenes, Vigdis

    2014-12-01

    An increasing number of drugs of abuse are sold word wide over the internet. Names like "legal highs", "herbal highs" etc. give the impression that these are safe products, although the risk of fatal reactions might be substantial. Leaves from the plant Mitragyna speciosa, contain active compounds like mitragynine and 7-hydroxymitragynine. It has been reported that the potency of 7-hydroxymitragynine at the μ-opioid receptor is 30 times higher than that of mitragynine and 17 times higher than that of morphine. Case reports regarding poisoning with Kratom are reported, but the toxic or lethal ranges for the concentrations of the active substances have not been established, and concentrations of 7-hydroxymitragynine have not been reported previously. We present a case report where a middle aged man was found dead at home. The deceased had a history of drug abuse and mental illness for several years. At autopsy, there were no significant pathological findings. Post-mortem analysis of peripheral blood revealed: zopiclone 0.043mg/L, citalopram 0.36mg/L and lamotrigine 5.4mg/L, i.e. concentrations regularly seen after therapeutic ingestion of these drugs. Additionally mitragynine 1.06mg/L and 7-hydroxymitragynine 0.15mg/L were detected in blood and both also in urine. The high concentrations of mitragynine and 7-hydroxymitragynine indicate that the cause of death is intoxication by these substances; and the circumstances point toward the manner of death being accidental. We recommend that both mitragynine and 7-hydroxymitragynine are analyzed for in cases with suspected Kratom intoxication. PMID:25453780

  13. Joint modeling of thermal creep and radiation damage interaction with gas permeability and release dynamics: The role of percolation

    NASA Astrophysics Data System (ADS)

    Ovaska, M.; Alava, M. J.

    2015-10-01

    Nuclear fuel material is an example of a sintered, porous ceramic material. We formulate a two-dimensional model which couples three physical mechanisms in the material: (scalar) damage accumulation by thermal creep and radiation effects, porosity changes due to the damage, and the time-dependent diffusion of (radiation-induced) gases in the pore system thus created. The most important effect in the dynamics arises from the process where the pore system is swept through the percolation transition. The main conclusions that can be drawn concern the fractional gas release and its dependence on the three effects present in the damage dynamics: creep, radiation-induced bubble formation, and recovery due to bubble closure. In the main, the model reproduces the experimentally observed quick gas release phenomenon qualitatively.

  14. OGRE/MOD1: A computer model for predicting off-gas release from In Situ Vitrification melts

    SciTech Connect

    MacKinnon, R.J.; Mousseau, V.A.

    1990-07-01

    The OGRE program is designed to compute off-gas release from In Situ Vitrification melt pools. This document describes the theoretical basis and computational algorithms used in the program. An outline of the computer program is described including presentation of an example user input deck. Two model problems are examined to verify the program and an example problem is given to demonstrate program usage.

  15. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a) (1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  16. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  17. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  18. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  19. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  20. Estimating release of polycyclic aromatic hydrocarbons from coal-tar contaminated soil at manufactured gas plant sites. Final report

    SciTech Connect

    Lee, L.S.

    1998-04-01

    One of EPRI`s goals regarding the environmental behavior of organic substances consists of developing information and predictive tools to estimate the release potential of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils at manufactured gas (MGP) plant sites. A proper assessment of the distribution of contaminants under equilibrium conditions and the potential for mass-transfer constraints is essential in evaluating the environmental risks of contaminants in the subsurface at MGP sites and for selecting remediation options. The results of this research provide insights into estimating maximum release concentrations of PAHs from MGP soils that have been contaminated by direct contact with the tar or through years of contact with contaminated groundwater. Attention is also given to evaluating the use of water-miscible cosolvents for estimating aqueous phase concentrations, and assessing the role of mass-transfer constraints in the release of PAHs from MGP site soils.

  1. Release of trace metals, sulfate and complexed cyanide from soils contaminated with gas-purifier wastes: a microcosm study.

    PubMed

    Rennert, T; Mansfeldt, T

    2006-01-01

    Deposited gas-purifier wastes are commonly contaminated with trace metals, sulfate and cyanide (CN) compounds. We investigated their release from three soils contaminated with gas-purifier wastes into solution in microcosm experiments under varying redox conditions (E(H) 170-620 mV). The soils differed in pH (2.2; 4.9; 7.4) and featured low amounts of trace metals, but large amounts of total S and total CN. The pH governed trace metal release in the case of the acidic soil and CN release in the case of the slightly alkaline soil. The redox potential controlled trace metal and CN release in the case of the moderately acidic soil. Sources of dissolved SO(4)(2-) were dissolution of gypsum, desorption from Fe oxides and probably oxidation of elemental S. The geochemical behaviors of trace metals (soluble under acidic and reducing conditions) and CN (soluble under alkaline and oxidizing conditions) were diametrically opposed. PMID:16019115

  2. Results of Large-Scale Testing on Effects of Anti-Foam Agent on Gas Retention and Release

    SciTech Connect

    Stewart, Charles W.; Guzman-Leong, Consuelo E.; Arm, Stuart T.; Butcher, Mark G.; Golovich, Elizabeth C.; Jagoda, Lynette K.; Park, Walter R.; Slaugh, Ryan W.; Su, Yin-Fong; Wend, Christopher F.; Mahoney, Lenna A.; Alzheimer, James M.; Bailey, Jeffrey A.; Cooley, Scott K.; Hurley, David E.; Johnson, Christian D.; Reid, Larry D.; Smith, Harry D.; Wells, Beric E.; Yokuda, Satoru T.

    2008-01-03

    The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site. The waste treatment process in the pretreatment facility will mix both Newtonian and non-Newtonian slurries in large process tanks. Process vessels mixing non-Newtonian slurries will use pulse jet mixers (PJMs), air sparging, and recirculation pumps. An anti-foam agent (AFA) will be added to the process streams to prevent surface foaming, but may also increase gas holdup and retention within the slurry. The work described in this report addresses gas retention and release in simulants with AFA through testing and analytical studies. Gas holdup and release tests were conducted in a 1/4-scale replica of the lag storage vessel operated in the Pacific Northwest National Laboratory (PNNL) Applied Process Engineering Laboratory using a kaolin/bentonite clay and AZ-101 HLW chemical simulant with non-Newtonian rheological properties representative of actual waste slurries. Additional tests were performed in a small-scale mixing vessel in the PNNL Physical Sciences Building using liquids and slurries representing major components of typical WTP waste streams. Analytical studies were directed at discovering how the effect of AFA might depend on gas composition and predicting the effect of AFA on gas retention and release in the full-scale plant, including the effects of mass transfer to the sparge air. The work at PNNL was part of a larger program that included tests conducted at Savannah River National Laboratory (SRNL) that is being reported separately. SRNL conducted gas holdup tests in a small-scale mixing vessel using the AZ-101 high-level waste (HLW) chemical simulant to investigate the effects of different AFAs, their components, and of adding noble metals. Full-scale, single-sparger mass transfer tests were also conducted at SRNL in water and AZ-101 HLW simulant to provide data for PNNL

  3. Investigation of Thermal Equilibrium around an Accidental Event and Impact on Possibly Enclosed Surrounding Environment

    NASA Astrophysics Data System (ADS)

    Sarkar, Biswanath; Shah, Nitin; Choukekar, Ketan; Kapoor, Himanshu; Kumar, Uday; Das, Jotirmoy; Bhattacharaya, Ritendra; Vaghela, Hitensinh; Muralidhara, Srinivasa

    Complex and large cryogenic distribution systems are integral part of a fusion machine having superconducting magnets, cryopumps, etc. The various equipment of the cryogenic distribution system are interconnected via Cryogenic Transfer Lines (CTLs) to distribute cold helium to end users. During nominal operation of the fusion machine, helium inventory in CTLs could be in order of several tons. The cold helium present in CTLs could be released in surrounding volume due to accidental scenario. The present analysis, aims to estimate lowest temperature in the surrounding volume due to accidental scenario. The paper will describe simulation results and the test plan in a simulated condition.

  4. WATRE: a computer program for analyzing water and gas release from heated concrete

    SciTech Connect

    Claybrook, S.W.

    1983-05-16

    The capabilities of the WATRE computer code for calculating water and CO/sub 2/ release from heated concrete have been significantly enhanced. The governing finite difference equations have been recast in implicit form to reduce time step limitations and increase computational efficiency. The water release model has been validated by comparison with data from several experiments. The CO/sub 2/ model has also been implemented and validation is in progress.

  5. Quantitation of gas-phase perfluoroalkyl surfactants and fluorotelomer alcohols released from nonstick cookware and microwave popcorn bags.

    PubMed

    Sinclair, Ewan; Kim, Seung Kyu; Akinleye, Henry B; Kannan, Kurunthachalam

    2007-02-15

    Fluoropolymer dispersions are used for coating certain cookware products and food-contact packaging to impart oil and water repellency. Since salts of perfluorooctanoic acid (PFOA) are used as a processing aid in the manufacture of many fluoropolymers, it is necessary to determine if these compounds are still present as residuals after the process used to coat nonstick cookware or packaging, and could be released during typical cooking conditions. In this study, we identified and measured perfluoroalkyl carboxylates (PFCAs), particularly PFOA, and fluorotelomer alcohols (FTOHs; 6:2 FTOH and 8:2 FTOH), released from nonstick cookware into the gas phase under normal cooking temperatures (179 to 233 degrees C surface temperature). PFOA was released into the gas phase at 7-337 ng (11-503 pg/cm2) per pan from four brands of nonstick frying pans. 6:2 FTOH and 8:2 FTOH were found in the gas phase of four brands of frying pans, and the sources of FTOHs released from nonstick cookware are under investigation. We observed a significant decrease in gas-phase PFOA following repeated use of one brand of pan, whereas the other brand did not show a significant reduction in PFOA release following multiple uses. PFOA was found at >5 ng during the fourth use of both brands of pans. FTOHs were not found after the second use of either brand of pans. PFOA was found at 5-34 ng in the vapors produced from a prepacked microwave popcorn bag. PFOA was not found in the vapors produced from plain white corn kernels popped in a polypropylene container. 6:2 FTOH and 8:2 FTOH were measured in the vapors produced from one brand of prepacked microwave popcorn at 223 + 37 ng and 258 +/- 36 ng per bag, respectively, but not measured at >20 ng (LOQ) in the other two brands. On the packaging surface of one brand of microwave popcorn several PFCAs, including C5-C12, 6:2 FTOH, and 8:2 FTOH, were found at concentrations in the order of 0.5-6.0 ng/cm2. This study suggests that residual PFOA is not

  6. METHODS AND RESULTS OF RECONSTRUCTION OF NOBLE GAS RELEASES FROM THE STACKS OF THE MAYAK PA GRAPHITE REACTORS OVER THE WHOLE PERIOD OF THEIR OPERATION

    SciTech Connect

    Glagolenko, Y. V.; Drozhko, Evgeniy G.; Mokrov, Y.; Pyatin, N. P.; Rovny, Sergey I.; Anspaugh, L. R.; Napier, Bruce A.

    2008-06-01

    Brief analysis of design features and operational modes of Mayak PA industrial graphite-uranium reactors (PUGRs) is given. The above mentioned Mayak PA PUGRs determined the rates of releases of radioactive noble gases (RNG) from activation (41Ar) and fission (isotopes of Krypton and Xenon) through the vent stack of the reactor. Information is given on methods and results of experimental determination of RNG atmospheric releases for the period starting from 1965 till PUGRs decommissioning in 1987-1990. A calculation method for reconstruction of radioactive noble gas releases is proposed and justified. The results of reconstruction are given. It is shown that maximum rates of RNG releases from PUGRs high stacks were observed in the 1950s, when ordinary atmospheric air was used as a cover gas for the reactor graphite stacks and gas purification systems (flow-type gas holders) had not been installed yet.

  7. Risk analysis approach. [of carbon fiber release

    NASA Technical Reports Server (NTRS)

    Huston, R. J.

    1979-01-01

    The assessment of the carbon fiber hazard is outlined. Program objectives, requirements of the risk analysis, and elements associated with the physical phenomena of the accidental release are described.

  8. The experimental study of the polonium-210 release from Li17-Pb83 eutectic

    SciTech Connect

    Schipakin, O.; Borisov, N.; Churkin, S.

    1994-12-31

    The polonium contamination hazard arise as a result of accidental Po-210 release from breeding blanket material - melted Li17Pb83 eutectic - in the environment. The experimental study of Po-210 release rates from eutectic were carry out in atmosphere of noble gases and air with different humidity in 1992-1993. In these experiments used method of carrier-gas flowing above melted eutectic surface. The main findings presented by RDIPE and Karpov Institute are: (1) The polonium-210 release rate strongly increase with eutectic temperature from 150 to 450{degrees}C. (2) The Po-210 release rate in the noble carrier-gas is in proportion with polonium concentration in eutectic in studied range from 10{sup {minus}7} to 10{sup {minus}4} Ci/g. (3) The Po-210 release rate in air remarkably effected by the surface oxide film also. (4) In these experiments for the first time were studied differently gaseous and aerosol polonium-210 fractions release rates. The experimental results and corresponding estimates showed needs the technological and accidental cleaning systems equipped by complex filters of gaseous and aerosols polonium-210 forms.

  9. Accidental paraffin poisoning in Kenyan children.

    PubMed

    Lang, T; Thuo, N; Akech, S

    2008-06-01

    A serious and common accident in rural Kenyan homesteads is accidental ingestion of paraffin when it has been mistaken for water and offered to a young child. Here we report the incidence, parental practices and outcome of severe paraffin poisoning, requiring admission at Kilifi District Hospital, Kenya. Over a 2-year period, 48 children (0.5% of all admissions) were admitted with kerosene poisoning, constituting 62% of all poisoning cases. All cases were accidental. Ten per cent had induced vomiting. One child (2%) died. We suggest these data support assessment followed by implementation of practical and affordable measures to prevent paraffin poisoning. PMID:18363584

  10. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2

    NASA Technical Reports Server (NTRS)

    Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Boehnhardt, H.; Magee-Sauer, K.

    2011-01-01

    We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet 103P/Hartley-2 using high dispersion infrared spectroscopy. We present production rates for individual volatiles species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates that span the interval Sept. - Dec. 2010. The production rates vary strongly with nucleus rotation, but the mixing ratios remain constant throughout the campaign. The released primary volatiles exhibit diverse spatial properties which favor the presence of separate polar and apolar ice phases in the nucleus, establish dust and gas release from icy clumps (and also, directly from the nucleus), and provide insights into the driver for the cyanogen (CN) polar jet.

  11. Overview study of LNG release prevention and control systems

    SciTech Connect

    Pelto, P.J.; Baker, E.G.; Holter, G.M.; Powers, T.B.

    1982-03-01

    The liquefied natural gas (LNG) industry employs a variety of release prevention and control techniques to reduce the likelihood and the consequences of accidental LNG releases. A study of the effectiveness of these release prevention and control systems is being performed. Reference descriptions for the basic types of LNG facilities were developed. Then an overview study was performed to identify areas that merit subsequent and more detailed analyses. The specific objectives were to characterize the LNG facilities of interest and their release prevention and control systems, identify possible weak links and research needs, and provide an analytical framework for subsequent detailed analyses. The LNG facilities analyzed include a reference export terminal, marine vessel, import terminal, peakshaving facility, truck tanker, and satellite facility. A reference description for these facilities, a preliminary hazards analysis (PHA), and a list of representative release scenarios are included. The reference facility descriptions outline basic process flows, plant layouts, and safety features. The PHA identifies the important release prevention operations. Representative release scenarios provide a format for discussing potential initiating events, effects of the release prevention and control systems, information needs, and potential design changes. These scenarios range from relatively frequent but low consequence releases to unlikely but large releases and are the principal basis for the next stage of analysis.

  12. Barium silicates of the Berisal Complex, Switzerland: A study in geochronology and rare-gas release systematics

    NASA Astrophysics Data System (ADS)

    Hetherington, C. J.; Villa, I. M.

    2007-07-01

    Barium silicate minerals such as celsian, ganterite, armenite, as well as Ba-bearing and Ba-free white mica from the Berisal Complex, Simplon Nappe, Swiss Alps, were dated by 39Ar- 40Ar. Ages of Ba-free micas are ca. 17 Ma, while Ba and parentless 40Ar are correlated in Ba silicates, suggesting common inheritance from the Paleozoic orthogneissic protolith. The release pattern of reactor-produced 39Ar (or 37Ar) from hydrated and anhydrous minerals is very similar, with apparent activation energies of ca. 180 kJ/mole and a conspicuous kink around 900 °C. White micas release Ar at higher temperature than the literature determination of their dehydroxylation. In addition to Ar, we studied the degassing of monoisotopic 131Xe produced from Ba during neutron irradiation. Xe is degassed at higher temperature than Ar, and again all analyzed silicates have the same apparent activation energy of ca. 300 kJ/mole. The decoupling of Ar and Xe rules out delamination as the dominant degassing mechanism in mica and implies that recoiled rare gas atoms mostly reside inside the T-O-T layers of the mica structure. The near-identical apparent activation energies in such diverse silicates as tecto-, phyllo- and cyclosilicate requires instead that the in-vacuo gas release kinetics are the same in all three silicates. As the only structural element common to these three silicate families are silica tetrahedra, it is possible that their well-known rotation plays a decisive role for in-vacuo Ar degassing; additional high-temperature in situ structural investigations on feldspars and micas would be needed to help constrain the mechanisms of laboratory Ar release.

  13. Interaction between hydrothermal and magmatic systems: modelling of magmatic gas release and ascent at Campi Flegrei (Italy)

    NASA Astrophysics Data System (ADS)

    Todesco, Micol; Afanasyev, Andrey; Montagna, Chiara Paola; Longo, Antonella

    2016-04-01

    We model the perturbation of a hydrothermal system caused by the gas release from sub-surface magma chambers. First, we simulate the evolution of the magmatic system composed by two magma reservoirs: a small and shallow chamber, filled with degassed phonolite, connected to a deeper reservoir of gas-rich shoshonite through a vertical dyke. The fluid-dynamics governing the replenishment of the upper chamber is computed with a 2D code solving conservation equations of mass, momentum and energy for a homogeneous multicomponent, multiphase Newtonian mixture, accounting for exsolution and dissolution of volatiles (H2O+CO2). We then assume that the volatiles that accumulate at the top of the upper chamber, escape from the reservoir and enter a steady state hydrothermal system. The response of the hydrothermal circulation is simulated with two multi-phase, multi-component porous media codes (MUFITS and TOUGH2) that describe the propagation of magmatic volatiles toward the surface. We create a simple model of Campi Flegrei hydrothermal system covering both shallow and deep regions where the temperature exceeds the critical temperature for water. Simulation results suggest that the rate at which volatiles are released from the magma chamber, the permeability distribution and the conditions of the hydrothermal system when degassing takes place can determine very different evolutions: accordingly, carbon dioxide may reach the surface within a time span ranging from weeks to millennia. The simulations indicate also that a single unrest event, associated with volatiles release from the chamber, can result in a periodic behaviour of observable parameters such as gas flux and fumarole composition. Duration of the period is of the order of 10 years, which is comparable with the time span between major unrest events observed at Campi Flegrei.

  14. Accidental Head Injury: A Real Life Experience.

    ERIC Educational Resources Information Center

    Blakely, Jim

    1988-01-01

    The adult victim of accidental head injury as a result of an automobile accident recounts his experiences as a brain injured adult with such problems as poor balance, poor speech, spasticity, and lack of fine motor movement. He emphasizes his determination to get on with his life. (DB)

  15. STEADY STATE FLAMMABLE GAS RELEASE RATE CALCULATION & LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE [SEC 1 & 2

    SciTech Connect

    HU, T.A.

    2003-09-30

    Flammable gases such as hydrogen, ammonia, and methane are observed in the tank dome space of the Hanford Site high-level waste tanks. This report assesses the steady-state flammability level under normal and off-normal ventilation conditions in the tank dome space for 177 double-shell tanks and single-shell tanks at the Hanford Site. The steady-state flammability level was estimated from the gas concentration of the mixture in the dome space using estimated gas release rates, Le Chatelier's rule and lower flammability limits of fuels in an air mixture. A time-dependent equation of gas concentration, which is a function of the gas release and ventilation rates in the dome space, has been developed for both soluble and insoluble gases. With this dynamic model, the time required to reach the specified flammability level at a given ventilation condition can be calculated. In the evaluation, hydrogen generation rates can be calculated for a given tank waste composition and its physical condition (e.g., waste density, waste volume, temperature, etc.) using the empirical rate equation model provided in Empirical Rate Equation Model and Rate Calculations of Hydrogen Generation for Hanford Tank Waste, HNF-3851. The release rate of other insoluble gases and the mass transport properties of the soluble gas can be derived from the observed steady-state gas concentration under normal ventilation conditions. The off-normal ventilation rate is assumed to be natural barometric breathing only. A large body of data is required to do both the hydrogen generation rate calculation and the flammability level evaluation. For tank waste that does not have sample-based data, a statistical-based value from probability distribution regression was used based on data from tanks belonging to a similar waste group. This report (Revision 3) updates the input data of hydrogen generation rates calculation for 177 tanks using the waste composition information in the Best-Basis Inventory Detail

  16. Retention of Tracer Gas from Instantaneous Releases of SF6 in an Urban Environment

    SciTech Connect

    Doran, J. C.; Allwine, K Jerry; Clawson, Kirk L.; Carter, Roger G.

    2006-01-01

    Data from a series of instantaneous releases of SF6 tracer during the Joint Urban 2003 study in Oklahoma City have been analyzed to determine characteristic retention times for puffs in an urban environment. Results from nine real-time tracer detectors with a time response of 0.5 seconds were used in the analysis. Distances from the source ranged from less than 200 m to over 1 km. For each individual intensive operating period (IOP), the detector locations were adjusted so that, given the expected wind directions during the releases, the detectors would lie generally downwind of the release point. As a result, building characteristics upwind of the detectors varied from one IOP to the next. Animations of the tracer concentrations show clear evidence of channeling along street canyons approximately parallel to the prevailing wind directions, trapping in street canyons perpendicular to the flow, and other complex circulation patterns. Retention times for individual puffs ranged from a few minutes to over 20 minutes, with a strong mode in the distribution around 11 minutes. There was surprisingly little correlation with wind speed or direction. Comparisons with simple puff models are presented.

  17. Antimicrobial activity of controlled-release chlorine dioxide gas on fresh blueberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of chlorine dioxide (ClO2) on the safety and quality of blueberries was studied. In vitro studies revealed that both ClO2 gas fumigation and ClO2 water direct contact killed food pathogen bacterium, Escherichia coli and fruit decay pathogen fungus, Colletotrichum acutatum. In vivo studies...

  18. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Accidental fire or other casualty. 158.27 Section... Casualty, Loss, or Theft While in Customs Custody § 158.27 Accidental fire or other casualty. In the case of injury or destruction by accidental fire or other casualty, the following evidence shall...

  19. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Accidental fire or other casualty. 158.27 Section... Casualty, Loss, or Theft While in Customs Custody § 158.27 Accidental fire or other casualty. In the case of injury or destruction by accidental fire or other casualty, the following evidence shall...

  20. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  1. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  2. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  3. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  4. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  5. Lander based hydroacoustic monitoring of marine single bubble releases in Eckernförde Bay utilizing the multibeam based GasQuant II system.

    NASA Astrophysics Data System (ADS)

    Urban, Peter; Schneider von Deimling, Jens; Greinert, Jens

    2015-04-01

    The GEOMAR Helmholtz Centre for Ocean Research Kiel is currently developing a Imagenex Delta T based lander system for monitoring and quantifying marine gas release (bubbles). The GasQuant II is built as the successor of the GasQuant I system (Greinert, 2008), that has been successfully used for monitoring tempo-spatial variability of gas release in the past (Schneider von Deimling et al., 2010). The new system is lightweight (40 kg), energy efficient, flexible to use and built for ROV deployment with autonomous operation of up to three days. A prototype has been successfully deployed in Eckernförde Bay during the R/V ALKOR cruise AL447 in October/November 2014 to monitor the tempo-spatial variability of gas bubble seepage and to detect a possible correlation with tidal variations. Two deployments, one in forward- and one in upward looking mode, reveal extensive but scattered single bubble releases rather than distinct and more continuous sources. While these releases are difficult to detect in forward looking mode, they can unambiguously be detected in the upward looking mode even for minor gas releases, bubble rising speeds can be determined. Greinert, J., 2008. Monitoring temporal variability of bubble release at seeps: The hydroacoustic swath system GasQuant. J. Geophys. Res. Oceans Vol. 113 Issue C7 CiteID C07048 113, 7048. doi:10.1029/2007JC004704 Schneider von Deimling, J., Greinert, J., Chapman, N.R., Rabbel, W., Linke, P., 2010. Acoustic imaging of natural gas seepage in the North Sea: Sensing bubbles controlled by variable currents. Limnol. Oceanogr. Methods 8, 155. doi:10.4319/lom.2010.8.155

  6. Controlled Freeze-thaw Experiments to Study Biogeochemical Process and its Effects on Greenhouse Gas Release in Arctic Soil Columns

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Kneafsey, T. J.; Tas, N.; Bill, M.; Ulrich, C.; Hubbard, S. S.

    2014-12-01

    Greenhouse gas release associated with permafrost thawing is one of the largest uncertainties in future climate prediction. Improvement of such prediction relies on a better representation of the interactions between hydrological, geochemical and microbial processes in the Arctic ecosystem that occur over a wide range of space and time scales and under dynamic freeze-thaw conditions. As part of the Next Generation Ecosystem Experiments in the Arctic (NGEE-Arctic), we conducted controlled laboratory freeze-thaw experiments to study greenhouse gas release in vertical permafrost soil columns with vertically heterogeneous hydrological, geochemical and microbial properties. The studies were performed using soil cores collected from the NGEE Barrow, AK site. Two cores collected next to each other with very similar soil structures were used for the experiment. One of the cores was destructively sampled for baseline characterization, and the second core was used for the freeze-thaw experiments. The core extends from the ground surface into the permafrost with roughly 40 cm of active layer. The column was instrumented with various sensors and sampling devices, including thermocouples, geophysical (electrical) sensors, and sampling ports for solids and fluids. The headspace of the soil column was purged with CO2 free air and the gas samples were collected periodically for greenhouse gas analysis. Our initial tests simulated seasonal temperature variation from ~ -10°C to +10°C at the ground surface. Our results demonstrated that temperature and geophysical data provided real time information on the freeze thaw dynamics of the column and the surface greenhouse gas fluxes correlated with the freeze thaw stages and associated hydrological and biogeochemical processes in the vertical soil column. For example, surface fluxes data revealed an early burst of GHG concentrations during the initial thawing of the surface ice rich layer of the soil, indicating the presence of trapped

  7. Thermally programmable gas storage and release in single crystals of an organic van der Waals host.

    PubMed

    Enright, Gary D; Udachin, Konstantin A; Moudrakovski, Igor L; Ripmeester, John A

    2003-08-20

    A single crystal of a low density form of guest-free p-tert-butylcalix[4]arene can take up and release small guest molecules by controlling the temperature and pressure without changing the structure. Using NMR spectroscopy with flowing hyperpolarized xenon, we have shown that at room temperature access of xenon to the pore system is difficult, whereas it is relatively easy at 100 degrees C. There are good prospects for simple van der Waals materials such as the title material to be used as programmable zeolite mimics. PMID:12914432

  8. Organic molecules in ices and their release into the gas phase

    NASA Astrophysics Data System (ADS)

    Fayolle, Edith; Oberg, Karin I.; Garrod, Robin; van Dishoeck, Ewine; Rajappan, Mahesh; Bertin, Mathieu; Romanzin, Claire; Michaut, Xavier; Fillion, Jean-Hugues

    2015-08-01

    Organic molecules in the early stages of star formation are mainly produced in icy mantles surrounding interstellar dust grains. Identifying these complex organics and quantifying their abundance during the evolution of young stellar objects is of importance to understand the emergence of life. Simple molecules in ices, up to methanol in size, have been identified in the interstellar medium through their mid-IR vibrations, but band confusion prevents detections of more complex and less abundant organic molecules in interstellar ices. The presence of complex organics on grains can instead be indirectly inferred from observations of their rotational lines in the gas phase following ice sublimation.Thermal sublimation of protostellar ices occurs when icy grains flow toward a central protostar, resulting in the formation of a hot-core or a hot-corinos. The high degree of chemical complexity observed in these dense and warm regions can be the results of i) direct synthesis on the grains followed by desorption, but also to ii) the desorption of precursors from the ice followed by gas-phase chemistry. I will show how spatially resolved millimetric observations of hot cores and cooler protostellar environments, coupled to ice observations can help us pinpoint the ice or gas-phase origin of these organic species.Organic molecules have also recently been observed in cold environments where thermal desorption can be neglected. The presence of these cold molecules in the gas phase is most likely due to non-thermal desorption processes induced by, for e.g., photon-, electron-, cosmic-ray-irradiation, shock, exothermic reactions... I will present laboratory and observational efforts that push our current understanding of these non-thermal desorption processes and how they could be use to quantify the amount of organics in ices.

  9. Towards the inclusion of open fabrication porosity in a fission gas release model

    NASA Astrophysics Data System (ADS)

    Claisse, Antoine; Van Uffelen, Paul

    2015-11-01

    A model is proposed for fission product release in oxide fuels that takes into account the open porosity in a mechanistic manner. Its mathematical framework, assumptions and limitations are presented. It is based on the model for open porosity in the sintering process of crystalline solids. More precisely, a grain is represented by a tetrakaidecahedron and the open porosity is represented by a continuous cylinder along the grain edges. It has been integrated in the TRANSURANUS fuel performance code and applied to the first case of the first FUMEX project as well as to neptunium and americium containing pins irradiated during the SUPERFACT experiment and in the JOYO reactor. The results for LWR and FBR fuels are consistent with the experimental data and the predictions of previous empirical models when the thermal mechanisms are the main drivers of the release, even without using a fitting parameter. They also show a different but somewhat expected behaviour when very high porosity fuels are irradiated at a very low burn-up and at low temperature.

  10. Application of the HGSYSTEM/UF{sub 6} model to simulate atmospheric dispersion of UF{sub 6} releases from uranium enrichment plants

    SciTech Connect

    Goode, W.D. Jr.; Bloom, S.G.; Keith, K.D. Jr.

    1995-03-01

    Uranium hexafluoride is a dense, reactive gas used in Gaseous Diffusion Plants (GDPs) to make uranium enriched in the {sup 235}U isotope. Large quantities of UF{sub 6} exist at the GDPs in the form of in-process gas and as a solid in storage cylinders; smaller amounts exist as hot liquid during transfer operations. If liquid UF{sub 6} is released to the environment, it immediately flashes to a solid and a dense gas that reacts rapidly with water vapor in the air to form solid particles of uranyl fluoride and hydrogen fluoride gas. Preliminary analyses were done on various accidental release scenarios to determine which scenarios must be considered in the safety analyses for the GDPS. These scenarios included gas releases due to failure of process equipment and liquid/gas releases resulting from a breach of transfer piping from a cylinder. A major goal of the calculations was to estimate the response time for mitigating actions in order to limit potential off-site consequences of these postulated releases. The HGSYSTEM/UF{sub 6} code was used to assess the consequences of these release scenarios. Inputs were developed from release calculations which included two-phase, choked flow followed by expansion to atmospheric pressure. Adjustments were made to account for variable release rates and multiple release points. Superpositioning of outputs and adjustments for exposure time were required to evaluate consequences based on health effects due to exposures to uranium and HF at a specific location.

  11. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2

    NASA Technical Reports Server (NTRS)

    Mumma, M. J.; Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Boehnhardt, H.; Magee-Sauer, K.

    2011-01-01

    We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet lO3P/Hartley-2 using high dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present production rates for individual species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates. The production rates for water, ethane, HCN, and methanol vary in a manner consistent with independent measures of nucleus rotation, but mixing ratios for HCN, C2H6, & CH3OH are independent of rotational phase. Our results demonstrate that the ensemble average composition of gas released from the nucleus is well defined, and relatively constant over the three-month interval (September 18 through December 1,7). If individual vents vary in composition, enough diverse vents must be active simultaneously to approximate (in sum) the bulk composition of the nucleus. The released primary volatiles exhibit diverse spatial properties which favor the presence of separate polar and apolar ice phases in the nucleus, establish dust and gas release from icy clumps, and from the nucleus, and provide insights into the driver for the cyanogen (CN) polar jet. The spatial distributions of C2H6 & HCN along the near-polar jet (UT 19.5 October) and nearly orthogonal to it (UT 22.5 October) are discussed relative to the origin of CN. The ortho-para ratio (OPR) of water was 2.85 +/- 0.20; the lower bound (2.65) defines T(sub spin) > 32 K. These values are consistent with results returned from ISO in 1997 .

  12. TEMPORAL AND SPATIAL ASPECTS OF GAS RELEASE DURING THE 2010 APPARITION OF COMET 103P/HARTLEY 2

    SciTech Connect

    Mumma, M. J.; Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Boehnhardt, H.; Magee-Sauer, K.

    2011-06-10

    We report measurements of eight primary volatiles (H{sub 2}O, HCN, CH{sub 4}, C{sub 2}H{sub 6}, CH{sub 3}OH, C{sub 2}H{sub 2}, H{sub 2}CO, and NH{sub 3}) and two product species (OH and NH{sub 2}) in comet 103P/Hartley 2 using high-dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present production rates for individual species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates. The production rates for water, ethane, HCN, and methanol vary in a manner consistent with independent measures of nucleus rotation, but mixing ratios for HCN, C{sub 2}H{sub 6}, and CH{sub 3}OH are independent of rotational phase. Our results demonstrate that the ensemble average composition of gas released from the nucleus is well defined and relatively constant over the three-month interval (September 18 through December 17). If individual vents vary in composition, enough diverse vents must be active simultaneously to approximate (in sum) the bulk composition of the nucleus. The released primary volatiles exhibit diverse spatial properties which favor the presence of separate polar and apolar ice phases in the nucleus, establish dust and gas release from icy clumps (and from the nucleus), and provide insights into the driver for the cyanogen (CN) polar jet. The spatial distributions of C{sub 2}H{sub 6} and HCN along the near-polar jet (UT October 19.5) and nearly orthogonal to it (UT October 22.5) are discussed relative to the origin of CN. The ortho-para ratio (OPR) of water was 2.85 {+-} 0.20; the lower bound (2.65) defines T{sub spin} > 32 K. These values are consistent with results returned from the Infrared Space Observatory in 1997.

  13. Accidental swallowing of orthodontic expansion appliance key.

    PubMed

    Monini, André da Costa; Maia, Luiz Guilherme Martins; Jacob, Helder Baldi; Gandini, Luiz Gonzaga

    2011-08-01

    Ingestion of a foreign object, including a dental object, can lead to a trip to the emergency room. This article describes the accidental swallowing of a key that was used to activate a rapid maxillary expander. An orthodontic patient swallowed the key while trying to activate the appliance at home. The object's trajectory was followed on radiographs until it was eliminated. Possible clinical complications, legal implications of this situation, and practices for prevention are described. PMID:21803265

  14. Gas Release Near Bullseye Vent - New Observations From NEPTUNE Canada's Seafloor Cable

    NASA Astrophysics Data System (ADS)

    Scherwath, M.; Spence, G.; Riedel, M.; Heesemann, M.

    2012-12-01

    Over the past six years many marine expeditions to the area of Bullseye Vent region at the Cascadia margin off Vancouver Island have provided evidence of intense degassing at the seafloor above gas hydrate fields. These gas plumes have usually been imaged with ship-based echosounders at frequencies of 12-38 kHz and also with remotely operated vehicles (ROVs) sector-scanning 675 kHz sonars. These intermittent observations show that plume activity varied from visit to visit in size and location, from the absence of bubbles or small plumes to large plumes from multiple sources raising to water depths of up to 500 m below the surface. However, long time intervals without any observations existed between funding cycles and cruises, and so a complete picture of degassing was lacking. Since the installation of the North-East Pacific Time-series Undersea Networked Experiments (NEPTUNE) Canada cabled observatory it is now possible to make permanent long-term observations on a continuous basis and compile a complete series of degassing observations that fill the gap in expedition-based monitoring. At NEPTUNE Canada's Site ODP 889 near Bullseye Vent a permanent 260 kHz multibeam sonar has been installed in May 2010 for initially one year, and since July 2012 rotational capability for a 360 degrees view has been available. We show correlations of degassing with currents, tidal pressure and ocean floor shaking. We also provide an overview of the underlying geologic structures and show our interpretation of degassing associated with faulting as well as recent erosion and outcropping sand-rich layers that feed the gas up the system.

  15. Fatal accidental burns in married women.

    PubMed

    Kumar, Virendra; Tripathi, Chandra Bhal

    2003-09-01

    Burning incidents amongst women are a major concern in India as it has become pervasive throughout all social strata and geographical areas. They may be homicidal, suicidal or accidental in nature. Here, in the study, the main objective is to present the different epidemiological and medicolegal aspects of accidental burns in the married women. In a cohort of 152 burned wives, 70 (46%) were accidental victims and these cases were analyzed accordingly for their different medicolegal and epidemiological aspects. Data were collected from personal interview and from examining the different documents related to death. In this series, most of the women were illiterate Hindu housewives hailing from joint families (i.e. multigenerational groups of related individuals living under a single roof) of rural community. The majority (60%) of the affected wives were 16-25 years of age at the time of the accident and sustained less than 90% total body surface area burn injury. Most had the survival period more than 1 day, and more than half of them died of septicaemia. PMID:14568773

  16. Time-lapse ground penetrating radar (GPR) measurements for exploring biogenic gas distribution and releases from peat soils in the Florida Everglades

    NASA Astrophysics Data System (ADS)

    Wright, W. J.; Comas, X.; Berber, M.

    2013-12-01

    Peat soils are known to release significant amounts of methane (CH4) and carbon dioxide (CO2) to the atmosphere. However, uncertainties still remain regarding the spatio-temporal distribution of gas accumulations and the triggering mechanisms of gas releasing events. Furthermore, most peatland gas dynamics research has historically been focused on high latitude peatlands, while recent works have suggested that gas production rates from low-latitude peat soils may be higher than those from colder climates. Ground penetrating radar (GPR) is a geophysical tool that has successfully been used in the past to non-invasively investigate the release of biogenic gasses from peat soils. This study is conducted in the Loxahatchee Impoundment Landscape Assessment (LILA), a hydrologically controlled, landscape scale (30 HA) model of the Florida Everglades. Here, temporal and spatial heterogeneity of gas releases from peat soil at the plot scale (<100 m2) are shown using a time series of three-dimensional (3D) GPR measurements. GPR data are supported by direct gas flux measurements using flux chambers combined with time-lapse photography, and surface deformation measurements using terrestrial LiDAR scanning and differential leveling.

  17. Flow-flame interactions causing acoustically coupled heat release fluctuations in a thermo-acoustically unstable gas turbine model combustor

    SciTech Connect

    Steinberg, A.M.; Boxx, I.; Stoehr, M.; Meier, W.; Carter, C.D.

    2010-12-15

    A detailed analysis of the flow-flame interactions associated with acoustically coupled heat-release rate fluctuations was performed for a 10 kW, CH{sub 4}/air, swirl stabilized flame in a gas turbine model combustor exhibiting self-excited thermo-acoustic oscillations at 308 Hz. High-speed stereoscopic particle image velocimetry, OH planar laser induced fluorescence, and OH* chemiluminescence measurements were performed at a sustained repetition rate of 5 kHz, which was sufficient to resolve the relevant combustor dynamics. Using spatio-temporal proper orthogonal decomposition, it was found that the flow-field contained several simultaneous periodic motions: the reactant flux into the combustion chamber periodically oscillated at the thermo-acoustic frequency (308 Hz), a helical precessing vortex core (PVC) circumscribed the burner nozzle at 515 Hz, and the PVC underwent axial contraction and extension at the thermo-acoustic frequency. The global heat release rate fluctuated at the thermo-acoustic frequency, while the heat release centroid circumscribed the combustor at the difference between the thermo-acoustic and PVC frequencies. Hence, the three-dimensional location of the heat release fluctuations depended on the interaction of the PVC with the flame surface. This motivated the compilation of doubly phase resolved statistics based on the phase of both the acoustic and PVC cycles, which showed highly repeatable periodic flow-flame configurations. These include flames stabilized between the inflow and inner recirculation zone, large-scale flame wrap-up by the PVC, radial deflection of the inflow by the PVC, and combustion in the outer recirculation zones. Large oscillations in the flame surface area were observed at the thermo-accoustic frequency that significantly affected the total heat-release oscillations. By filtering the instantaneous reaction layers at different scales, the importance of the various flow-flame interactions affecting the flame area was

  18. Template copolymerization to control site structure around metal ions: Applications towards sensing and gas storage and release

    NASA Astrophysics Data System (ADS)

    Mitchell-Koch, Jeremy T.

    The development of functional materials for sensing and gas storage and release is useful in a number of chemical and biological applications. Investigating function of molecularly imprinted polymers (MIP), often used for these purposes, has relied on circumstantial evidence because direct examination of immobilized sites is not possible. Described in this dissertation is the design, synthesis, characterization and function studies of materials synthesized by template copolymerization methods. Metal ions exhibit unique spectroscopic properties and their utilization makes site examination more feasible. Ligand binding modulates these properties such that the event can be measured by spectroscopy. The metal ion's secondary coordination environment can also be tuned to increase or decrease function of the material. In Chapter Two the utilization of template copolymerization to immobilize a europium-containing compound for the detection of volatile organic compounds is described. Luminescence of the immobilized complex is quenched in the presence of volatile organic compounds (VOC). The quenching effect is dependent on concentration of VOC and the nature of polymeric host. Chapters Three and Four describe the development of materials for the photolytic release of nitric oxide (NO). In Chapter Three, a novel manipulation of the immobilized complex is employed to produce binding sites that contain ligands covalently embedded into the host in a position to bind the metal ion upon NO release in order to block rebinding. Incompatible binding affinities of the iron-containing templates made it impossible to study NO photo-release from this material. Second-row transition metals are more compatible with NO binding, and Chapter Four describes a ruthenium salen-containing polymer that releases NO in response to light. Additionally, transfer of NO to a metalloporphyrin and myoglobin has been achieved. This is the first report of photolytic heterogeneous NO transfer by a material

  19. Petroleum and hazardous material releases from industrial facilities associated with Hurricane Katrina.

    PubMed

    Santella, Nicholas; Steinberg, Laura J; Sengul, Hatice

    2010-04-01

    Hurricane Katrina struck an area dense with industry, causing numerous releases of petroleum and hazardous materials. This study integrates information from a number of sources to describe the frequency, causes, and effects of these releases in order to inform analysis of risk from future hurricanes. Over 200 onshore releases of hazardous chemicals, petroleum, or natural gas were reported. Storm surge was responsible for the majority of petroleum releases and failure of storage tanks was the most common mechanism of release. Of the smaller number of hazardous chemical releases reported, many were associated with flaring from plant startup, shutdown, or process upset. In areas impacted by storm surge, 10% of the facilities within the Risk Management Plan (RMP) and Toxic Release Inventory (TRI) databases and 28% of SIC 1311 facilities experienced accidental releases. In areas subject only to hurricane strength winds, a lower fraction (1% of RMP and TRI and 10% of SIC 1311 facilities) experienced a release while 1% of all facility types reported a release in areas that experienced tropical storm strength winds. Of industrial facilities surveyed, more experienced indirect disruptions such as displacement of workers, loss of electricity and communication systems, and difficulty acquiring supplies and contractors for operations or reconstruction (55%), than experienced releases. To reduce the risk of hazardous material releases and speed the return to normal operations under these difficult conditions, greater attention should be devoted to risk-based facility design and improved prevention and response planning. PMID:20345576

  20. Assessing changes in stratospheric mean age of air and fractional release using historical trace gas observations

    NASA Astrophysics Data System (ADS)

    Laube, Johannes; Bönisch, Harald; Engel, Andreas; Röckmann, Thomas; Sturges, William

    2014-05-01

    Large-scale stratospheric transport is pre-dominantly governed by the Brewer-Dobson circulation. Due to climatic change a long-term acceleration of this residual stratospheric circulation has been proposed (e.g. Austin et al.,2006). Observational evidence has revealed indications for temporary changes (e.g. Bönisch et al., 2011) but a confirmation of a significant long-term trend is missing so far (e.g. Engel et al., 2009). A different aspect is a possible long-term change in the break-down of chemically important species such as chlorofluorocarbons as proposed by Butchart et al. 2001. Recent studies show significant differences adding up to more than 20 % in the chlorine released from such compounds (Newman et al., 2007; Laube et al., 2013). We here use a data set of three long-lived trace gases, namely SF6, CF2Cl2, and N2O, as measured in whole-air samples collected during balloon and aircraft flights between 1975 and 2011, to assess changes in stratospheric transport and chemistry. For this purpose we utilise the mean stratospheric transit times (or mean ages of air) in combination with a measure of the chemical decomposition (i.e. fractional release factors). We also evaluate the influence of different trend correction methods on these quantities and explore their variability with latitude, altitude, and season. References Austin, J. & Li, F.: On the relationship between the strength of the Brewer-Dobson circulation and the age of stratospheric air, Geophys. Res. Lett., 33, L17807, 2006. Bönisch, H., Engel, A., Birner, Th., Hoor, P., Tarasick, D. W., and Ray, E. A.: On the structural changes in the Brewer-Dobson circulation after 2000, Atmos. Chem. Phys., 11, 3937-3948, 2011. Butchart, N. & Scaife, A. A. Removal of chlorofluorocarbons by increased mass exchange between the stratosphere and troposphere in a changing climate. Nature, 410, 799-802, 2001. Engel, A., Möbius, T., Bönisch, H., Schmidt, U., Heinz, R., Levin, I., Atlas, E., Aoki, S., Nakazawa, T

  1. Probabilistic consequence model of accidenal or intentional chemical releases.

    SciTech Connect

    Chang, Y.-S.; Samsa, M. E.; Folga, S. M.; Hartmann, H. M.

    2008-06-02

    In this work, general methodologies for evaluating the impacts of large-scale toxic chemical releases are proposed. The potential numbers of injuries and fatalities, the numbers of hospital beds, and the geographical areas rendered unusable during and some time after the occurrence and passage of a toxic plume are estimated on a probabilistic basis. To arrive at these estimates, historical accidental release data, maximum stored volumes, and meteorological data were used as inputs into the SLAB accidental chemical release model. Toxic gas footprints from the model were overlaid onto detailed population and hospital distribution data for a given region to estimate potential impacts. Output results are in the form of a generic statistical distribution of injuries and fatalities associated with specific toxic chemicals and regions of the United States. In addition, indoor hazards were estimated, so the model can provide contingency plans for either shelter-in-place or evacuation when an accident occurs. The stochastic distributions of injuries and fatalities are being used in a U.S. Department of Homeland Security-sponsored decision support system as source terms for a Monte Carlo simulation that evaluates potential measures for mitigating terrorist threats. This information can also be used to support the formulation of evacuation plans and to estimate damage and cleanup costs.

  2. Effect of duckweed cover on greenhouse gas emissions and odour release from waste stabilisation ponds.

    PubMed

    van der Steen, N P; Nakiboneka, P; Mangalika, L; Ferrer, A V M; Gijzen, H J

    2003-01-01

    Treatment of wastewater in stabilisation pond systems prevents the negative environmental impact of uncontrolled disposal of sewage. However, even a natural treatment system may generate secondary negative environmental impacts in terms of energy consumption, emission of greenhouse gases and emission of odorous compounds. Whereas natural systems have an advantage over electro-mechanical systems in that they use less hardware and less energy, it is not yet known whether secondary environmental effects in the form of greenhouse gas emissions are lower for these systems. This research intends to be a first step in the direction of answering this question by assessing gas emissions from two types of natural systems, namely algae-based and duckweed-based stabilisation ponds. The H2S volatilisation from laboratory scale pond-reactors has been determined by drawing the air above the water surface continuously through a solution of 1 M NaOH for absorption of sulphide. The amount of H2S that volatilised from the algae pond-reactor, and was trapped in the NaOH trap, was found to be 2.5-86 mg/m2/day. The H2S volatilisation from the duckweed pond-reactor was found to be negligible, even though the sulphide concentration was 9.7 mg/l S(2-). The duckweed cover was a physical barrier for volatilisation, since bubbles were trapped in the cover. In addition the duckweed layer was found to be afavourable environment for both aerobic sulphide oxidisers (Beggiatoa gigantae) as well as for photosynthetic purple sulphur bacteria belonging to the genus Chromatium. These may also have contributed to the prevention of H2S volatilisation. Results on methane emissions were not conclusive so far, but the same mechanisms that prevent H2S volatilisation may also prevent methane volatilisation. Therefore it was concluded that duckweed covers on stabilisation ponds may reduce the emission of both odorous and greenhouse gases. PMID:14510229

  3. Photoacoustic trace gas detection of ethene released by UV-induced lipid peroxidation in humans

    NASA Astrophysics Data System (ADS)

    Cristescu, Simona M.; Berkelmans, Rik; te Lintel Hekkert, Sacco; Timmerman, Brenda H.; Parker, David H.; Harren, Frans J. M.

    2000-11-01

    A sensitive CO2 laser-based photoacoustic (PA) detector has been used to perform non-invasive and on-line measurements of ethene (C2H4) production from exhaled air and directly emitted from the skin. Ethene was used as indicator for free- radicals induced lipid peroxidation in the skin of human subjects exposed to ultraviolet (UV) radiation from a solarium. Ethene from the exhaled air was analyzed for a group of 21 male subjects at rest. During 15 minutes of UV exposure, the average ethene emission was 17.2 pmol/kg/min (SD 7.3), while the pre-UV exposure levels were 1.4 pmol/kg/min (SD 0.38). Different types of sun protection creams were tested by means of ethene release in exhaled air. The influence of UV radiation intensity and of exposure time (10 and 15 minutes, respectively) on the ethene emission from the skin has been studied for a second group of 12 subjects. Comparison between measurements of exhaled air and directly on the skin is presented.

  4. Screening of inorganic gases released from firework-rockets by a gas chromatography/whistle-accelerometer method.

    PubMed

    Chen, Kuan-Fu; Wu, Hui-Hsin; Lin, Chien-Hung; Lin, Cheng-Huang

    2013-08-30

    The use of an accelerometer for detecting inorganic gases in gas chromatography (GC) is described. A milli-whistle was connected to the outlet of the GC capillary and was used instead of a classical GC detector. When the GC carrier gases and the sample gases pass through the milli-whistle, a sound is produced, leading to vibrational changes, which can be recorded using an accelerometer. Inorganic gases, including SO2, N2 and CO2, which are released from traditional Chinese firework-rockets at relatively high levels as the result of burning the propellant and explosive material inside could be rapidly determined using the GC/whistle-accelerometer system. The method described herein is safe, the instrumentation is compact and has potential to be modified so as to be portable for use in the field. It also can be used in conjunction with FID (flame ionization detector) or TCD (thermal conductivity detector), in which either no response for FID (CO2, N2, NO2, SO2, etc.) or helium gas is needed for TCD, respectively. PMID:23891209

  5. Source of released carbon fibers

    NASA Technical Reports Server (NTRS)

    Bell, V. L.

    1979-01-01

    The potential for the release of carbon fibers from aircraft crashes/fires is addressed. Simulation of the conditions of aircraft crash fires in order to predict the quantities and forms of fibrous materials which might be released from civilian aircraft crashes/fires is considered. Figures are presented which describe some typical fiber release test activities together with some very preliminary results of those activities. The state of the art of carbon fiber release is summarized as well as some of the uncertainties concerning accidental fiber release.

  6. Containing the accidental laboratory escape of potential pandemic influenza viruses

    PubMed Central

    2013-01-01

    Background The recent work on the modified H5N1 has stirred an intense debate on the risk associated with the accidental release from biosafety laboratory of potential pandemic pathogens. Here, we assess the risk that the accidental escape of a novel transmissible influenza strain would not be contained in the local community. Methods We develop here a detailed agent-based model that specifically considers laboratory workers and their contacts in microsimulations of the epidemic onset. We consider the following non-pharmaceutical interventions: isolation of the laboratory, laboratory workers’ household quarantine, contact tracing of cases and subsequent household quarantine of identified secondary cases, and school and workplace closure both preventive and reactive. Results Model simulations suggest that there is a non-negligible probability (5% to 15%), strongly dependent on reproduction number and probability of developing clinical symptoms, that the escape event is not detected at all. We find that the containment depends on the timely implementation of non-pharmaceutical interventions and contact tracing and it may be effective (>90% probability per event) only for pathogens with moderate transmissibility (reproductive number no larger than R0 = 1.5). Containment depends on population density and structure as well, with a probability of giving rise to a global event that is three to five times lower in rural areas. Conclusions Results suggest that controllability of escape events is not guaranteed and, given the rapid increase of biosafety laboratories worldwide, this poses a serious threat to human health. Our findings may be relevant to policy makers when designing adequate preparedness plans and may have important implications for determining the location of new biosafety laboratories worldwide. PMID:24283203

  7. Preliminary Study of Strong-Sludge Gas Retention and Release Mechanisms in Clay Simulants

    SciTech Connect

    Gauglitz, Phillip A.; Buchmiller, William C.; Probert, Samuel G.; Owen, Antionette T.

    2010-10-12

    The Hanford Site has 28 double-shell tanks (DSTs) and 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. The mission of the Department of Energy’s River Protection Project is to retrieve and treat the Hanford tank waste for disposal and close the tank farms. A key aspect of the mission is to retrieve and transfer waste from the SSTs, which are at greater risk for leaking, into DSTs for interim storage until the waste is transferred to and treated in the Waste Treatment and Immobilization Plant. There is, however, limited space in the existing DSTs to accept waste transfers from the SSTs, and approaches to overcoming the limited DST space will benefit the overall mission. The purpose of this study is to summarize and analyze the key previous experiment that forms the basis for the relaxed controls and to summarize initial progress and results on new experiments focused on understanding the conditions that result in low gas retention. The work is ongoing; this report provides a summary of the initial findings. The previous large-scale test used about 50 m3 of sediment, which would be unwieldy for doing multiple parametric experiments. Accordingly, experiments will begin with smaller-scale tests to determine whether the desired mechanisms can be studied without the difficulty of conducting very large experiments.

  8. Effects of energy release on near field flow structure of gas jets

    NASA Technical Reports Server (NTRS)

    Agrawal, Ajay K.; Gollahalli, Subramanyam R.; Griffin, Devon

    1995-01-01

    The primary objective is to understand how buoyancy affects the structure of the shear layer, the development of fluid dynamic instabilities, and formation of the coherent structures in the near-nozzle regions of gas jets. The secondary objectives are to study the role of buoyancy in lifting and reattachment process of diffusion flames, to evaluate the scaling behavior of diffusion flames, and to aid development and/or validation of theoretical models by providing quantitative data in the absence of buoyancy. Fast reacting hydrogen or hydrogen-inert fuels are used to isolate the effects of buoyancy on fluid dynamics without masking the flame behavior by soot and radiative heat transfer. This choice of fuel also permits an evaluation of simulating low gravity in low pressure ground experiments because the similarity constraints are relaxed for the fast reacting, nonsooting diffusion flames. The diagnostics consists primarily of a color schlieren system coupled with computer generated rainbow filters, video recording, and image analysis. The project involves (1) drop tower experiments, (2) ground experiments, and (3) theoretical analysis.

  9. Accidental Kähler moduli inflation

    SciTech Connect

    Maharana, Anshuman; Rummel, Markus; Sumitomo, Yoske

    2015-09-14

    We study a model of accidental inflation in type IIB string theory where inflation occurs near the inflection point of a small Kähler modulus. A racetrack structure helps to alleviate the known concern that string-loop corrections may spoil Kähler Moduli Inflation unless having a significant suppression via the string coupling or a special brane setup. Also, the hierarchy of gauge group ranks required for the separation between moduli stabilization and inflationary dynamics is relaxed. The relaxation becomes more significant when we use the recently proposed D-term generated racetrack model.

  10. Toxic chemical considerations for tank farm releases. Revision 1

    SciTech Connect

    Van Keuren, J.C.

    1995-11-01

    This document provides a method of determining the toxicological consequences of accidental releases from Hanford Tank Farms. A determination was made of the most restrictive toxic chemicals that are expected to be present in the tanks. Concentrations were estimated based on the maximum sample data for each analyte in all the tanks in the composite. Composite evaluated were liquids and solids from single shell tanks, double shell tanks, flammable gas watch list tanks, as well as all solids, all liquids, head space gases, and 241-C-106 solids. A sum of fractions of the health effects was computed for each composite for unit releases based emergency response planning guidelines (ERPGs). Where ERPGs were not available for chemical compounds of interest, surrogate guidelines were established. The calculation method in this report can be applied to actual release scenarios by multiplying the sum of fractions by the release rate for continuous releases, or the release amount for puff releases. Risk guidelines are met if the product is less than for equal to one.

  11. Accidental gamma dose measurement using commercial glasses.

    PubMed

    Narayan, Pradeep; Vaijapurkar, S G; Senwar, K R; Kumar, D; Bhatnagar, P K

    2008-01-01

    Commercial glasses have been investigated for their application in accidental gamma dose measurement using Thermoluminescent (TL) techniques. Some of the glasses have been found to be sensitive enough that they can be used as TL dating material in radiological accident situation for gamma dosimetry with lower detection limit 1 Gy (the dose significant for the onset of deterministic biological effects). The glasses behave linearly in the dose range 1-25 Gy with measurement uncertainty +/- 10%. The errors in accidental dose measurements using TL technique are estimated to be within +/- 25%. These glasses have shown TL fading in the range of 10-20% in 24 h after irradiation under room conditions; thereafter the fading becomes slower and reaches upto 50% in 15 d. TL fading of gamma-irradiated glasses follows exponential decay pattern, therefore dosimetry even after years is possible. These types of glasses can also be used as lethal dose indicator (3-4 Gy) using TL techniques, which can give valuable inputs to the medical professional for better management of radiation victims. The glasses are easy to use and do not require lengthy sample preparation before reading as in case of other building materials. TL measurement on glasses may give immediate estimation of the doses, which can help in medical triage of the radiation-exposed public. PMID:18285317

  12. Accidental radioisotope burns - Management of late sequelae.

    PubMed

    Varghese, Bipin T; Thomas, Shaji; Nair, Balakrishnan; Mathew, P C; Sebastian, Paul

    2010-09-01

    Accidental radioisotope burns are rare. The major components of radiation injury are burns, interstitial pneumonitis, acute bone marrow suppression, acute renal failure and adult respiratory distress syndrome. Radiation burns, though localized in distribution, have systemic effects, and can be extremely difficult to heal, even after multiple surgeries. In a 25 year old male who sustained such trauma by accidental industrial exposure to Iridium192 the early presentation involved recurrent haematemesis, pancytopenia and bone marrow suppression. After three weeks he developed burns in contact areas in the left hand, left side of the chest, abdomen and right inguinal region. All except the inguinal wound healed spontaneously but the former became a non-healing ulcer. Pancytopenia and bone marrow depression followed. He was treated with morphine and NSAIDs, epidural buprinorphine and bupivicaine for pain relief, steroids, antibiotics followed by wound excision and reconstruction with tensor fascia lata(TFL) flap. Patient had breakdown of abdominal scar later and it was excised with 0.5 cm margins up to the underlying muscle and the wound was covered by a latissimis dorsi flap. Further scar break down and recurrent ulcers occurred at different sites including left wrist, left thumb and right heel in the next two years which needed multiple surgical interventions. PMID:21321664

  13. Scaling Laws for Reduced-Scale Tests of Pulse Jet Mixing Systems in Non-Newtonian Slurries: Gas Retention and Release Behavior

    SciTech Connect

    Stewart, Charles W.; Meyer, Perry A.; Kurath, Dean E.; Barnes, Steven M.

    2006-03-02

    The Waste Treatment Plant (WTP) under construction at the Hanford Site will use pulse jet mixer (PJM) technology for mixing and gas retention control applications in tanks expected to contain waste slurries exhibiting a non-Newtonian rheology. This paper presents the results of theoretical and experimental studies performed to establish the methodology to perform reduced-scale gas retention and release tests with PJM systems in non-Newtonian fluids with gas generation. The technical basis for scaled testing with unsteady jet mixing systems in gas-generating non-Newtonian fluids is presented in the form of a bubble migration model that accounts for the gas generation rate, the average bubble rise velocity, and the geometry of the vessel. Scaling laws developed from the model were validated with gas holdup and release tests conducted at three scales: large scale, 1/4 scale, and 1/9 scale. Experiments were conducted with two non-Newtonian simulants with in-situ gas generation by decomposition of hydrogen peroxide. The data were compared non-dimensionally, and the important scale laws were examined. From these results, scaling laws are developed which allow the design of mixing systems at a reduced scale.

  14. EPA (ENVIRONMENTAL PROTECTION AGENCY) DEVELOPING METHODS TO ASSESS ENVIRONMENTAL RELEASE

    EPA Science Inventory

    The EPA has invested considerable research effort--intended to meet regulatory needs--toward developing methods for assessing the environmental effects of genetically engineered microorganisms (GEMs). Preliminary investigations centered on the fate, survival, accidental release, ...

  15. Consequence Analyses Following Potential Savannah River Site Hydrological Releases

    SciTech Connect

    Blanchard, A.

    1999-07-28

    Postulated accidental release of radiological material to surface water bodies on the Savannah River Site and the resulting downstream contamination of the Savannah River pose a potential threat to downstream river users.

  16. FEMAXI-V benchmarking study on peak temperature and fission gas release prediction of PWR rod fuel

    SciTech Connect

    Suwardi; Dewayatna, W.; Briyatmoko, B.

    2012-06-06

    The present paper reports a study of FEMAXI-V code and related report on code benchmarking. Capabilities of the FEMAXI-V code to predict the thermal and fission gas release have been tested on MOX fuels in LWRs which has been done in SCK{center_dot}CEN and Belgonucleaire by using PRIMO MOX rod BD8 irradiation experiment after V Sobolev as reported O. J. Ott. Base irradiation in the BR3 reactor, the BD8 rod was transported to CEA-Saclay for irradiation in the OSIRIS reactor (ramp power excursion). The irradiation device used for the PRIMO ramps was the ISABELLE 1 loop, installed on a movable structure of the core periphery. The power variations were obtained by inwards/backwards movements of the loop in the core water. The preconditioning phase for rod BD8 occurred at a peak power level of 189 W/cm with a hold time of 27 hours. The subsequent power excursion rate amounted to 77 W/ (cm.min), reaching a terminal peak power level of 395 W/cm that lasted for 20 hours.

  17. Gas dispersion measurements using a mobile Raman lidar system

    NASA Technical Reports Server (NTRS)

    Houston, J. D.; Brown, D. R.

    1986-01-01

    The exploitation of natural gas resources to supply energy demands has resulted in the need to engineer pipelines and plants capable of handling extremely high pressures and throughputs. Consequently, more attention has been directed to evaluating the consequences of releases of material whether accidental or deliberate in nature. An important aspect of assessing the consequences of a release is an understanding of how gas disperses in the atmosphere over a wide range of release and atmospheric conditions. The most cost effective way of providing such information is through the development and use of reliable theoretical prediction methods. The need for some form of remote sensing device was identified. The various possibilities studied led to the conclusion that LIDAR (Light Detection And Ranging) offered the most suitable method. The system designed and built is described, and its recent use in monitoring operational ventings from a high pressure transmission system is discussed.

  18. Total flammable mass and volume within a vapor cloud produced by a continuous fuel-gas or volatile liquid-fuel release.

    PubMed

    Epstein, Michael; Fauske, Hans K

    2007-08-25

    The top-hat jet/plume model has recently been employed to obtain simple closed-form expressions for the mass of fuel in the flammable region of a vapor "cloud" produced by an axisymmetric (round) continuous-turbulent jet having positive or negative buoyancy [1]. The fuel release may be a gas or a volatile liquid. In this paper, the top-hat analysis is extended to obtain closed-form approximate expressions for the total mass (fuel+entrained air) and volume of the flammable region of a release cloud produced by either a round or a plane (two-dimensional) buoyant jet. These expressions lead to predicted average fuel concentrations in the flammable regions of the release clouds which, when compared with the stoichiometric concentration, serve as indicators of the potential severity of release cloud explosions. For a fixed release mass, the combustion overpressure following ignition of a hydrogen/air cloud is anticipated to be significantly lower than that due to ignition of a hydrocarbon/air cloud. The predicted average hydrogen concentration within the flammable region of the release cloud is below the lower detonability limit. The facility with which the expressions can be used for predictions of combustion overpressures is illustrated for propane releases and deflagrations in a closed compartment. PMID:17363152

  19. The Potential for Buoyant Displacement Gas Release Events in Tank 241-SY-102 after Waste Transfer from Tank 241-SY-101

    SciTech Connect

    Wells, Beric E.; Meyer, Perry A.; Chen, Guang

    2000-04-10

    Tank 241-SY-101 is a double-shell radioactive waste storage tank containing waste that, before recent transfer and water back-dilution operations, was capable of retaining gas and producing flammable buoyant displacement gas release events (BD GREs). A BD GRE occurs when a portion of the nonconvective layer waste retains enough gas to become buoyant, rises to the waste surface, breaks up, and releases some of the stored gas. Installing the mixer pump in 1993 successfully mitigated gas retention in the settled solids layer in SY-101 and has prevented BD GREs. Gas retention in the floating drust layer and the corresponding accelerated waste level growth made it necessary to begin waste removal and back-dilution with water in December 1999. During these operations, some of the SY-101 mixed slurry layer is removed and transferred into Tank 241-SY-102. There was some concern that adding the SY-101 waste into SY-102 could create a waste configuration in SY-102 capable of BD GREs. This report updates and extends earlier assessments of the potential for BD GRE conditions in SY-102 after waste is transferred from SY-101. We determined that, under the given assumptions, no possibility of BD GREs exists in SY-102 from the SY-101 waste being added during from December 1999 through March 2000.

  20. The Effect of Increased Salinity and Temperature in Peat Soils from the Everglades: Implications for Biogenic Gas Production and Release Under a Sea Level Rise Scenario

    NASA Astrophysics Data System (ADS)

    Sirianni, M.; Comas, X.

    2015-12-01

    Sea level rise (SLR) is an increasingly important topic for many low-lying coastal areas such as South Florida. The United States Army Corps of Engineers (USACE) projects that sea level change in South Florida, over the next 50 years, will increase between 0.1 and 0.6 meters. Given the low elevation and its shallow slope, the Everglades region is highly susceptible to changes in sea level. Based on the USACE SLR projections it seems inevitable that previously unexposed freshwater areas of the southern Everglades will become increasingly exposed to saline water. The effects of such saline water intrusion into the current C dynamics of the Everglades (particularly in terms of biogenic gas production and emissions, i.e. CH4 and CO2) is however uncertain. As previously proposed by others, increases in salinity in peat soils will result in dilation of pore spaces and thus increases in hydraulic conductivity, while limiting methanogenesis. However, increases in temperature may induce the opposite effect, particularly in terms of methanogenic activity. Previous studies investigating the effects of increased salinity on freshwater peat soils in the Everglades are very limited, and to our knowledge none have intended to monitor the internal gas dynamics within the peat matrix using an array of geophysical and hydrological methods such as ground penetrating radar (GPR), time-lapse photography, gas chromatography, and constant head permeameter tests. Preliminary laboratory results showed (1) a progressive decrease in gas content within the peat matrix (i.e. production) and gas releases once fluid conductivity is increased; (2) a progressive increase in hydraulic conductivity once fluid conductivity is increased; and (3) maximum gas releases detected during early stages of pore dilation (after increasing salinity) followed by a progressive decrease in gas release as salinity increased. This study has implications for better understanding how C dynamics in the Everglades may be

  1. Accidental infant death and stroller-prams.

    PubMed

    Byard, R W; Beal, S M; Simpson, A; Carter, R F; Khong, T Y

    1996-08-01

    A three-month-old boy and an eight-month-old boy died from accidental positional asphyxia and hanging, respectively, after being placed to sleep unsupervised in stroller-prams. Both infants had moved down towards the fronts of the stroller-prams. The younger infant fell out when the footplate collapsed and he was found hanging from a metal bar on the side. The older infant had partly slipped through the front and was suspended with his head and arms within the stroller-pram and with his face pushed firmly into the mattress by a horizontal metal bar. Stroller-prams are a potentially dangerous sleeping environment unless infants are closely supervised, gaps in the front of stroller-prams closed and upright footplates stabilised. PMID:8709876

  2. [Accidental myiasis by Ornidia obesa in humans].

    PubMed

    Monteiro, Silvia G; Faccio, Lucian; Otto, Mateus Anderson; Soares, João Fabio; Da Silva, Aleksandro S; Mazzanti, Alexandre

    2008-09-01

    Dipterous of the genus Ornidia are pollinator bugs, but immature stages can be found in organic matter in decomposition. This article refers to a found of larvae of Ornidia obesa in humans feces. An eight years old child was treated in a medical clinic due to the presence of two larvae and one pupae in the feces, hyperthermia, intestinal obstruction and strong abdominal pain. Medical therapy consisted of Mebendazol and Ivermectin in the indicated doses. 24 hours after the administration of the drugs, several larvae were expelled with diarrheic feces. The material was taken to the Parasitological Veterinary Lab, and the larvae were classified belonging to the genus Ornidia. According to the literature, this specie of Diptera is not incriminated to cause myiasis in vertebrates. We think that this study reports a case of accidental myiasis in humans, were the patient may have ingested food with immature stages of the fly (eggs or larvae). PMID:20059825

  3. Rickettsial infection caused by accidental conjunctival inoculation.

    PubMed

    Brissos, Joao; de Sousa, Rita; Santos, Ana Sofia; Gouveia, Catarina

    2015-01-01

    The most common transmission route of tick-borne Rickettsia is through tick bite; nevertheless, other transmission routes should also be considered. We report a case of rickettsial infection in a 15-year-old boy caused by accidental contamination of the conjunctiva through the infected fluid of a crushed engorged tick removed from a dog. Right eye pain, conjunctival hyperaemia with mucopurulent exudate, chemosis and eyelid oedema were the first signs and symptoms. Two days later, the boy developed fever, myalgia, headache, abdominal pain and was vomiting; physical examination showed multiple cervical adenopathies but no rash. He was treated with doxycycline (200 mg/day) for 7 days with progressive resolution of clinical signs. Rickettsial infection was confirmed by immunofluorescence assay with serological seroconversion in two consecutive samples. Rickettsia conorii or Rickettsia massiliae were the possible causal agents since they are the Rickettsia spp found in the Rhipicephalus sanguineus dog tick in Portugal. PMID:25568272

  4. Throat-cutting of accidental origin.

    PubMed

    Demirci, Serafettin; Dogan, Kamil Hakan; Gunaydin, Gursel

    2008-07-01

    Incised wounds of the neck can be accidental, homicidal, or suicidal. In this paper, a death case has been presented where a spinning circular saw of a cutting machine in a workshop came off its place and cut the throat of a 30-year-old male who was operating the machine. There was an incision (15 cm x 5 cm) that began in the middle of the neck down the thyroid cartilage, extended horizontally to the left of the neck and ended on the outer part of the neck in the outer left side of m. trapezius. Death occurred because of exsanguination caused by the cutting of carotis artery and jugular vein. In the case we presented, although the cut in the neck initially suggested homicide, it was found to have occurred as a result of an accident after the autopsy and death scene investigation. PMID:18489556

  5. Accidental etizolam ingestion in a child.

    PubMed

    Kato, Zenichiro; Nakamura, Mitsuhiro; Funato, Michinori; Kuwabara, Hideaki; Kondo, Naomi

    2007-07-01

    Etizolam (ETZ) is an antidepressive thienodiazepine drug that is used worldwide. The most frequent adverse effects in adults are drowsiness and muscle weakness, and this can rarely cause paradoxical excitation; however, no information exists on intoxication in children. Furthermore, evidence bearing on its safety in children is not available. We present a case of a child who accidentally took a single dose of ETZ, approximately the same as a therapeutic dose for adults, and who showed paradoxical excitation and muscle weakness. The case presented here suggests that pediatricians and emergency physicians should be aware of the possible adverse effects in children and therapeutic approaches in intoxication of ETZ and the necessity of further investigations on a specific therapeutic guideline for overdose management especially in children. PMID:17666930

  6. Accidental Deaths Among British Columbia Indians

    PubMed Central

    Schmitt, N.; Hole, L. W.; Barclay, W. S.

    1966-01-01

    A statistical and epidemiological review of British Columbia native Indian and non-Indian mortality revealed that accidents were the leading cause of death among Indians but ranked only fourth among non-Indians. Comparison of accidental death rates by age and sex showed that, without exception, the rates among Indians were considerably higher than the corressponding rates for non-Indians. While the Indians represented some 2% of the total population of British Columbia, they accounted for over 10% of the total accident fatalities, 29% of drownings, and 21% of fatal burns. Socioeconomic, environmental and psychosocial factors and excessive drinking are considered the chief causes responsible for this rather unusual epidemiological phenomenon. This study revealed certain hazardous conditions which are specific to the Indian's present way of life. In the authors' opinion the recognition of these specific hazards is imperative for the planning of effective preventive campaigns. PMID:5902238

  7. Experiences of Causing an Accidental Death: An Interpretative Phenomenological Analysis

    ERIC Educational Resources Information Center

    Rassool, Sara B.; Nel, Pieter W.

    2012-01-01

    Accidentally killing or feeling responsible for another person's death constitutes an event that is different from many typical traumatic stressors in that the responsibility for causing the trauma is located in the person themselves, rather than another person or persons. Research exploring the perspective of those who have accidentally caused a…

  8. Course Management Systems for Learning: Beyond Accidental Pedagogy

    ERIC Educational Resources Information Center

    McGee, Patricia; Carmean, Colleen; Jafari, Ali

    2005-01-01

    "Course Management Systems for Learning: Beyond Accidental Pedagogy" is a comprehensive overview of standards, practices and possibilities of course management systems in higher education. "Course Management Systems for Learning: Beyond Accidental Pedagogy" focuses on what the current knowledge is (in best practices, research, standards and…

  9. 49 CFR 192.195 - Protection against accidental overpressuring.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Protection against accidental overpressuring. 192.195 Section 192.195 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE... Pipeline Components § 192.195 Protection against accidental overpressuring. (a) General...

  10. Gas release from comets

    NASA Technical Reports Server (NTRS)

    Notesco, G.; Kleinfeld, I.; Laufer, D.; Bar-Nun, A.

    1991-01-01

    The quantities of such volatiles as CO, CO2, and CH4 trapped in cometary water ice are of great importance in the determination of solar nebula temperature and composition in the regions of their formation. Experiments with water ice are presently noted to retain trapped gases beyond the temperature of amorphous ice's transformation to cubic ice; the retention of gases which emerge during the transformation of the cubic form to hexagonal (as well as during evaporation) occurs to a degree that is linearly dependent on the thickness of the ice layer.

  11. Greenhouse gas emissions and reactive nitrogen releases from rice production with simultaneous incorporation of wheat straw and nitrogen fertilizer

    NASA Astrophysics Data System (ADS)

    Xia, Longlong; Xia, Yongqiu; Ma, Shutan; Wang, Jinyang; Wang, Shuwei; Zhou, Wei; Yan, Xiaoyuan

    2016-08-01

    Impacts of simultaneous inputs of crop straw and nitrogen (N) fertilizer on greenhouse gas (GHG) emissions and N losses from rice production are not well understood. A 2-year field experiment was established in a rice-wheat cropping system in the Taihu Lake region (TLR) of China to evaluate the GHG intensity (GHGI) as well as reactive N intensity (NrI) of rice production with inputs of wheat straw and N fertilizer. The field experiment included five treatments of different N fertilization rates for rice production: 0 (RN0), 120 (RN120), 180 (RN180), 240 (RN240), and 300 kg N ha-1 (RN300, traditional N application rate in the TLR). Wheat straws were fully incorporated into soil before rice transplantation. The meta-analytic technique was employed to evaluate various Nr losses. Results showed that the response of rice yield to N rate successfully fitted a quadratic model, while N fertilization promoted Nr discharges exponentially (nitrous oxide emission, N leaching, and runoff) or linearly (ammonia volatilization). The GHGI of rice production ranged from 1.20 (RN240) to 1.61 kg CO2 equivalent (CO2 eq) kg-1 (RN0), while NrI varied from 2.14 (RN0) to 10.92 g N kg-1 (RN300). Methane (CH4) emission dominated the GHGI with a proportion of 70.2-88.6 % due to direct straw incorporation, while ammonia (NH3) volatilization dominated the NrI with proportion of 53.5-57.4 %. Damage costs to environment incurred by GHG and Nr releases from current rice production (RN300) accounted for 8.8 and 4.9 % of farmers' incomes, respectively. Cutting N application rate from 300 (traditional N rate) to 240 kg N ha-1 could improve rice yield and nitrogen use efficiency by 2.14 and 10.30 %, respectively, while simultaneously reducing GHGI by 13 %, NrI by 23 %, and total environmental costs by 16 %. Moreover, the reduction of 60 kg N ha-1 improved farmers' income by CNY 639 ha-1, which would provide them with an incentive to change the current N application rate. Our study suggests that GHG

  12. Mechanisms of gas bubble retention and release: results for Hanford Waste Tanks 241-S-102 and 241-SY-103 and single-shell tank simulants

    SciTech Connect

    Gauglitz, P.A.; Rassat, S.D.; Bredt, P.R.; Konynenbelt, J.H.; Tingey, S.M.; Mendoza, D.P.

    1996-09-01

    Research at Pacific Northwest National Laboratory (PNNL) has probed the physical mechanisms and waste properties that contribute to the retention and release of flammable gases from radioactive waste stored in underground tanks at Hanford. This study was conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. The wastes contained in the tanks are mixes of radioactive and chemical products, and some of these wastes are known to generate mixtures of flammable gases, including hydrogen, nitrous oxide, and ammonia. Because these gases are flammable, their retention and episodic release pose a number of safety concerns.

  13. Clinical clues for head injuries amongst Malaysian infants: accidental or non-accidental?

    PubMed

    Thalayasingam, M; Veerakumarasivam, A; Kulanthayan, S; Khairuddin, F; Cheah, I G S

    2012-12-01

    Identifying the differences between infants with non-accidental head injuries (NAHI) and accidental head injuries (AHI) may help alert clinicians to recognize markers of abuse. A retrospective review of infants <1 year of age admitted to a tertiary referral centre in Malaysia over a two year period with a diagnosis of head injury or abnormal computed tomography head scans was conducted to identify the clinical features pointing towards a diagnosis of NAHI by comparing the socio-demographics, presenting complaints, clinical features and the extent of hospital investigations carried out. NAHI infants were more likely to be symptomatic, under a non-related caregiver's supervision, and presented with inconsistent or no known mechanism of injury. Subdural haemorrhages were more common in NAHI infants. The history, mechanism of injury, presenting signs and symptoms as well as the nature of the injuries sustained are all valuable clues as to whether a head injury sustained during infancy is likely to be accidental or not. PMID:22424957

  14. Death scene evaluation in a case of fatal accidental carbon monoxide toxicity.

    PubMed

    Sedda, Antioco Franco; Rossi, Gabriele

    2006-12-20

    Exposure of humans to high concentrations of carbon monoxide can result in death, due to the formation of carboxyhaemoglobin (COHb), which impairs the oxygen carrying capacity of the haemoglobin. Carbon monoxide is responsible of a great number of accidental domestic poisonings and deaths throughout the world, particularly in homes that have faulty or poorly vented combustion appliances. A case is reported, in which a 21-year-old woman was found dead, due to carbon monoxide poisoning from a gas water heater, despite the puzzling evidence that the heater has been used for more than 10 years without any problem. An evaluation of the exposure to CO was performed, by measuiring the rate of production of CO from the heater, and using the Coburn-Forster-Kane equation to describe the kinetics of the poisoning process. The death was attributed to an accidental poisoning from carbon monoxide due to a sum of unfortunate circumstances. PMID:16439085

  15. Greenhouse gas fluxes and NO release from a Chinese subtropical rice-winter wheat rotation system under nitrogen fertilizer management

    NASA Astrophysics Data System (ADS)

    Yao, Zhisheng; Zheng, Xunhua; Wang, Rui; Dong, Haibo; Xie, Baohua; Mei, Baoling; Zhou, Zaixing; Zhu, Jianguo

    2013-06-01

    synthetic nitrogen fertilizers play an important role in increasing cereal grain yields, there have been increased concerns about their intensive utilization and environmental consequences. The overall goal of this study is to gain an insight into the integrated evaluation of greenhouse gas emission and nitric oxide (NO) release and grain yield as affected by nitrogen fertilization in a subtropical rice-wheat rotation system. The assessment was based on four consecutive yearly measurements of the fluxes of methane (CH4), nitrous oxide (N2O) and ecosystem respiration (CO2), and the simultaneous observation of NO emissions in nonrice seasons under three fertilization practices (i.e., the conventional farmers' practice with common nitrogen application rate, an alternative practice with reduced nitrogen input, and no nitrogen application as a control). Clearly, these trace gas fluxes showed largely intra-annual and interannual variations, highlighting the importance of entire year measurement for multiple years to achieve representative annual estimates. The annual mean CH4 fluxes varied from 95 kg C ha-1 (7.8 kg C t-1 grain) for the farmers' practice to 205 kg C ha-1 (25.7 kg C t-1 grain) for the control, indicating that nitrogen fertilization inhibited CH4 emissions. Across all the years, the annual N2O emissions increased exponentially with an increasing nitrogen rate and harvested aboveground biomass. The annual N2O emission averaged 1.3-5.3 kg N ha-1(159-444 g N t-1 grain) for all treatments. The annual direct emission factors of N2O-N tended to increase with increasing nitrogen rate and averaged 0.61% and 0.85% for the alternative and farmers' practices, respectively. Over all nonrice seasons, the seasonal mean NO emissions ranged from 0.15 to 1.4 kg N ha-1(58-253 g N t-1 grain), and were equivalent to 0.43% to 0.54% of the applied nitrogen. Averaging across the 4 years, the annual aggregate emissions of CH4 and N2O were 7.4 t CO2-eq ha-1(928 kg CO2-eq t-1grain

  16. Evolution of the cosmological mass density of neutral gas from Sloan Digital Sky Survey II - Data Release 7

    NASA Astrophysics Data System (ADS)

    Noterdaeme, P.; Petitjean, P.; Ledoux, C.; Srianand, R.

    2009-10-01

    We present the results of a search for damped Lyman-α (DLA) systems in the Sloan Digital Sky Survey II (SDSS), Data Release 7. We use a fully automatic procedure to identify DLAs and derive their column densities. The procedure is checked against the results of previous searches for DLAs in SDSS. We discuss the agreements and differences and show the robustness of our procedure. For each system, we obtain an accurate measurement of the absorber's redshift, the H I column density and the equivalent width of associated metal absorption lines, without any human intervention. We find 1426 absorbers with 2.15 < z < 5.2 with log N(H I) ≥ 20, out of which 937 systems have log N(H I) ≥ 20.3. This is the largest DLA sample ever built, made available to the scientific community through the electronic version of this paper. In the course of the survey, we discovered the intervening DLA with highest H I column density known to date with log N(H I) = 22.0±0.1. This single system provides a strong constraint on the high-end of the N(H I) frequency distribution now measured with high accuracy. We show that the presence of a DLA at the blue end of a QSO spectrum can lead to important systematic errors and propose a method to avoid them. This has important consequences for the measurement of the cosmological mass density of neutral gas at z ~ 2.2 and therefore on our understanding of galaxy evolution over the past 10 billion years. We find a significant decrease of the cosmological mass density of neutral gas in DLAs, Ω_g^DLA, from z = 4 to z = 2.2, consistent with the result of previous SDSS studies. However, and contrary to other SDSS studies, we find that Ω_g^DLA(z = 2.2) is about twice the value at z = 0. This implies that Ω_g^DLA keeps decreasing at z < 2.2. Catalog is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/505/1087

  17. The effect of water vapor on the release of fission gas from the fuel elements of high temperature, gas-cooled reactors: A preliminary assessment of experiments HRB-17, HFR-B1, HFR-K6 and KORA

    SciTech Connect

    Myers, B.F.

    1995-09-01

    The effect of water vapor on the release of fission gas from the fuel elements of high temperature, gas-cooled reactors has been measured in different laboratories under both irradiation and post irradiation conditions. The data from experiments HRB-17, HFR-B1, HFR-K6, and in the KORA facility are compared to assess their consistency and complimentarily. The experiments are consistent under comparable experimental conditions and reveal two general mechanisms involving exposed fuel kernels embedded in carbonaceous materials. One is manifest as a strong dependence of fission gas release on the partial pressure of water vapor below 1 kPa and the other, as a weak dependence above 1 kPa.

  18. Measurements of gas sorption from seawater and the influence of gas release on open-cycle ocean thermal energy conversion (OC-OTEC) system performance

    SciTech Connect

    Penney, T R; Althof, J A

    1985-06-01

    The technical community has questioned the validity and cost-effectiveness of open-cycle ocean thermal energy conversion (OC-OTEC) systems because of the unknown effect of noncondensable gas on heat exchanger performance and the power needed to run vacuum equipment to remove this gas. To date, studies of seawater gas desorption have not been prototypical for system level analysis. This study gives preliminary gas desorption data on a vertical spout, direct contact evaporator and multiple condenser geometries. Results indicate that dissolved gas can be substantially removed before the seawater enters the heat exchange process, reducing the uncertainty and effect of inert gas on heat exchanger performance.

  19. The bandmerged Planck Early Release Compact Source Catalogue: probing sub-structure in the molecular gas at high Galactic latitude

    NASA Astrophysics Data System (ADS)

    Chen, X.; Chary, R.; Pearson, T. J.; McGehee, P.; Fowler, J. W.; Helou, G.

    2016-06-01

    The Planck Early Release Compact Source Catalogue (ERCSC) includes nine lists of highly reliable sources, individually extracted at each of the nine Planck frequency channels. To facilitate the study of the Planck sources, especially their spectral behaviour across the radio/infrared frequencies, we provide a `bandmerged' catalogue of the ERCSC sources. This catalogue consists of 15 191 entries, with 79 sources detected in all nine frequency channels of Planck and 6818 sources detected in only one channel. We describe the bandmerging algorithm, including the various steps used to disentangle sources in confused regions. The multifrequency matching allows us to develop spectral energy distributions of sources between 30 and 857 GHz, in particular across the 100 GHz band, where the energetically important CO J = 1→0 line enters the Planck bandpass. We find ˜3σ-5σ evidence for contribution to the 100 GHz intensity from foreground CO along the line of sight to 147 sources with |b|>{30°}. The median excess contribution is 4.5 ± 0.9 per cent of their measured 100 GHz flux density which cannot be explained by calibration or beam uncertainties. This translates to 0.5 ± 0.1 K km s-1 of CO which must be clumped on the scale of the Planck 100 GHz beam, i.e. ˜10 arcmin. If this is due to a population of low-mass (˜15 M⊙) molecular gas clumps, the total mass in these clumps may be more than 2000 M⊙. Further, high-spatial-resolution, ground-based observations of the high-latitude sky will help shed light on the origin of this diffuse, clumpy CO emission.

  20. The potential for buoyant displacement gas release events in Tank 241-SY-102 after waste transfer from Tank 241-SY-101

    SciTech Connect

    BE Wells; PE Meyer; G Chen

    2000-05-10

    Tank 241-SY-101 (SY-101) is a double-shell, radioactive waste storage tank with waste that, before the recent transfer and water back-dilution operations, was capable of retaining gas and producing buoyant displacement (BD) gas release events (GREs). Some BD GREs caused gas concentrations in the tank headspace to exceed the lower flammability limit (LFL). A BD GRE occurs when a portion of the nonconvective layer retains enough gas to become buoyant, rises to the waste surface, breaks up, and releases some of its stored gas. The installation of a mixer pump in 1993 successfully mitigated gas retention in the settled solids layer in SY-101 and has since prevented BD GREs. However, operation of the mixer pump over the years caused gas retention in the floating crust layer and a corresponding accelerated waste level growth. The accelerating crust growth trend observed in 1997--98 led to initiation of sequences of waste removal and water back-dilutions in December 1999. Waste is removed from the mixed slurry layer in Tank SY-101 and transferred into Tank 241-Sy-102 (SY-102). Water is then added back to dissolve soluble solids that retain gas. The initial transfer of 89,500 gallons of SY-101 waste, diluted in-line at 0.94:1 by volume with water, to SY-102 was conducted in December 1999. The second transfer of 230,000 gallons of original SY-101 waste, diluted approximately 0.9:1, was completed in January 2000, and the third transfer of 205,500 gallons of original SY-101 waste diluted at 0.9:1 was completed in March 2000.

  1. Mechanisms of gas retention and release: Experimental results for Hanford single-shell waste tanks 241-A-101, 241-S-106, and 241-U-103

    SciTech Connect

    Rassat, S.D.; Caley, S.M.; Bredt, P.R.; Gauglitz, P.A.; Rinehart, D.E.; Forbes, S.V.

    1998-09-01

    The 177 underground waste storage tanks at the Hanford Site contain millions of gallons of radioactive waste resulting from the purification of nuclear materials and related processes. Through various mechanisms, flammable gas mixtures of hydrogen, ammonia, methane, and nitrous oxide are generated and retained in significant quantities within the waste in many ({approximately}25) of these tanks. The potential for large releases of retained gas from these wastes creates a flammability hazard. It is a critical component of the effort to understand the flammability hazard and a primary goal of this laboratory investigation to establish an understanding of the mechanisms of gas retention and release in these wastes. The results of bubble retention experimental studies using waste samples from several waste tanks and a variety of waste types support resolution of the Flammable Gas Safety Issue. Gas bubble retention information gained in the pursuit of safe storage will, in turn, benefit future waste operations including salt-well pumping, waste transfers, and sluicing/retrieval.

  2. Controlled release of encapsulated bioactive volatiles by rupture of the capsule wall through the light-induced generation of a gas.

    PubMed

    Paret, Nicolas; Trachsel, Alain; Berthier, Damien L; Herrmann, Andreas

    2015-02-01

    The encapsulation of photolabile 2-oxoacetates in core-shell microcapsules allows the light-induced, controlled release of bioactive compounds. On irradiation with UVA light these compounds degrade to generate an overpressure of gas inside the capsules, which expands or breaks the capsule wall. Headspace measurements confirmed the light-induced formation of CO and CO2 and the successful release of the bioactive compound, while optical microscopy demonstrated the formation of gas bubbles, the cleavage of the capsule wall, and the leakage of the oil phase out of the capsule. The efficiency of the delivery system depends on the structure of the 2-oxoacetate, the quantity used with respect to the thickness of the capsule wall, and the intensity of the irradiating UVA light. PMID:25589352

  3. Prediction of Peak Hydrogen Concentrations for Deep Sludge Retrieval in Tanks AN-101 and AN-106 from Historical Data of Spontaneous Gas Release Events

    SciTech Connect

    Wells, Beric E.; Cooley, Scott K.; Meacham, Joseph E.

    2013-10-21

    Radioactive and chemical wastes from nuclear fuel processing are stored in large underground storage tanks at the Hanford Site. The Tank Operations Contractor is continuing a program of moving solid wastes from single-shell tanks (SSTs) to double-shell tanks (DSTs) and preparing for waste feed delivery (WFD). A new mechanism for a large spontaneous gas release event (GRE) in deep sludge sediments has been postulated. The creation of this potential new GRE hazard, deep sludge gas release events (DSGREs), is the retrieval of sludge waste into a single DST that results in a sediment depth greater than operating experience has demonstrated is safe. The Tank Operations Contractor program of moving solid wastes from SSTs to DSTs and preparing for WFD is being negatively impacted by this sediment depth limit.

  4. Safety assessment for proposed pump mixing operations to mitigate episodic gas releases in tank 241-101-SY: Hanford Site, Richland, Washington

    SciTech Connect

    Lentsch, J.W., Westinghouse Hanford

    1996-05-16

    This safety assessment addresses each of the elements required for the proposed action to remove a slurry distributor and to install, operate, and remove a mixing pump in Tank 241-SY-101, which is located within the Hanford Site, Richland, Washington. The proposed action is required as part of an ongoing evaluation of various mitigation concepts developed to eliminate episodic gas releases that result in hydrogen concentrations in the tank dome space that exceed the lower flammability limit.

  5. A safety assessment for proposed pump mixing operations to mitigate episodic gas releases in tank 241-SY-101: Hanford Site,Richland, Washington

    SciTech Connect

    Lentsch, J.W.

    1996-07-01

    This safety assessment addresses each of the elements required for the proposed action to remove a slurry distributor and to install, operate, and remove a mixing pump in Tank 241-SY-101,which is located within the Hanford Site, Richland, Washington.The proposed action is required as part of an ongoing evaluation of various mitigation concepts developed to eliminate episodic gas releases that result in hydrogen concentrations in the tank dome space that exceed the lower flammability limit.

  6. The role of environmental accidental risk assessment in the process of granting development consent.

    PubMed

    Kontic, Branko; Gerbec, Marko

    2009-11-01

    Environmental impact assessment (EIA) is a procedure that must be followed for certain types of development before they are granted development consent. The procedure requires the developer to compile an environmental impact report (EIR) describing the likely significant effects of the project on the environment. A regulatory requirement in Slovenia is that an accidental risk assessment for a new installation should be a part of an EIR. The article shows how risk assessment (RA) related to accidental release of methylene diphenyl diisocyanate (MDI) or a polyvalent alcohol mixture from a new planned unit of a chemical factory in the Alpine region of Slovenia was performed in the framework of an EIA for the purpose of obtaining a construction permit. Two accidental scenarios were considered: (a) a spill of 20 m(3) of MDI or polyvalent alcohol mixture into the river Soca (the river runs close to the chemical factory) and (b) a fire in the warehouse storing the raw material, where emission of toxic gases HCN, NO(x), and CO is expected during combustion of MDI. One of the most important results of this case is the agreement among the developer, the competent authority, and a consultant in the field of EIA and RA to positively conclude the licensing process despite the absence of formal (regulatory) limit values for risk. It has been approved that transparent, reasonably uncertain, and semi-quantitative environmental risk assessment is an inevitable component of an EIA, and an essential factor in informed, licensing-related decision making. PMID:19732394

  7. Release of iron-cyanide complexes form contaminated soils - Batch and column experiments on substrates from Manufactured Gas Plant (MGP) site

    NASA Astrophysics Data System (ADS)

    Sut, Magdalena; Repmann, Frank; Raab, Thomas

    2013-04-01

    Soils of former Manufactured Gas Plants (MGPs) are often contaminated with iron-cyanide (Fe-CN) complexes that originate from gas purification process. Cyanide is a potentially toxic substance and its presence in soil and groundwater may cause risk for human health as well as for the environment. MGPs were commonly built on the city suburban areas, which have spread ever since. Nowadays, these sites are typically located in inner cities, causing environmental thread, due to the leaching of pollutants. More recently, columns and batch experiments have been used to study fate and mobility of contaminants is soil. The release of iron-cyanide complexes under unsaturated flow conditions was evaluated with eight columns of 30 cm length and a diameter of 5,4 cm. Cyanide concentrations in the collected leachates were measured with Flow Injection Analysis (FIA). Additionally pH, electrical conductivity (EC) and various ion concentrations were determined. In order to compare the release of Fe-CN complexes in saturated conditions a batch experiment was conducted, where in defined time intervals, 1 ml of the extract water phase was analyzed for CN concentration. Study revealed an analogous trend of cyanide release in both experiments indicating primarily the release of formerly dissolved phase (hexacyanoferrates) followed by continual dissolution of ferric ferrocyanide. We conclude that batch experiments, conducted prior to column analysis, can serve as preliminary prediction of the water soluble cyanide fraction under unsaturated conditions.

  8. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 4. Routine Releases, 1953 - 1972

    SciTech Connect

    Peterson, S

    2007-08-15

    Lawrence Livermore National Laboratory was founded in September 1952. By 1953, operations involving tritium were underway. Annual doses to an adult, a child (age 10), and an infant (age six months to one year) from tritium released routinely from the Livermore site between 1953 and 1972 were calculated using the tritium dose model, DCART. Uncertainties about sources and release rates are high, particularly for the 1950's, and it was difficult, and sometimes impossible (e.g., when a source was only assumed to have existed) to quantify them accurately. Because of this, every effort was made to assure that the uncertainties applied to the input parameters used in DCART would result in doses that could not have been exceeded. Doses were calculated at the potential locations of the hypothetical site-wide maximally exposed individual (SWMEI), which were at a residence on Vasco Road inside the present west perimeter of the Laboratory (1953 - 1958), at an automotive garage on East Avenue (1961), and at the Discovery Center (1959, 1960, 1962 - 1972, years which predate the facility). Even with the most conservative, screening model assumptions, the highest dose to the SW-MEI (in 1957) was predicted with 95% probability to have been between 27 and 370 {micro}Sv (2.7 and 37 mrem), with the most likely dose being 130 {micro}Sv (13 mrem). Using more realistic, but still conservative assumptions about what fraction of the diet could have been contaminated, these predictions were reduced by more than a factor of two. All other annual doses (at the 97.5% confidence limits) to the SW-MEI, calculated with the most conservative and health protective assumptions, were less than 200 {micro}Sv (20 mrem), and no dose after 1958 could have exceeded 100 {micro}Sv (10 mren). The cumulative dose to the hypothetical individual at the west perimeter location for 1953 through 1972 would have been no greater than 860 {micro}Sv (83 mrem), while the dose to the individual born and raised there

  9. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 3. Routine Releases, 1973 - 2005

    SciTech Connect

    Peterson, S

    2007-08-15

    Annual mean concentrations of tritium in air moisture, calculated from data obtained from an air tritium sampler near the LLNL Discovery Center, were compared with annual mean air moisture concentrations predicted from atmospheric releases of tritium for the years 1973 through 2005. The 95% confidence intervals on the predictions and observations usually overlapped. When the distributions of predictions and observations were different, predictions were higher. Using both the observed and predicted air concentrations as input to the tritium dose model, DCART, annual doses to a hypothetical adult, child (age 10) and infant (age 6 months to 1 year) assumed to be living at LLNL's Discovery Center were calculated. Although the doses based on predicted air concentrations tended to be higher, they were nevertheless indistinguishable from doses based on observed air concentrations when uncertainties were taken into account. Annual doses, calculated by DCART and based on observed and predicted air concentrations, were compared with historical tritium doses reported annually by LLNL. Although the historical doses were calculated using various assumptions over the years, their agreement with the DCART predictions is remarkable. The Discovery Center was not the location of the site-wide maximally exposed individual (SWMEI) from 1974 through 1978. However, doses at the location of the SW-MEI for those years were indistinguishable from those at the Discovery Center when uncertainties were taken into account. The upper confidence limits for all doses were always well below the current regulatory limit for dose to a member of the public (100 {micro}Sv or 10 mrem per year) from atmospheric releases (40 CFR Part 61, Subpart H). Based on observed air concentrations, the 97.5% confidence limit on the cumulative dose to the hypothetical person born in 1973 and living through 2005 at the Discovery Center was 150 {micro}Sv (15 mrem), while that of the hypothetical adult who spent his

  10. [Psychological aspects of accidental poisoning in children].

    PubMed

    Trabach-Valadier, C; Floret, D

    1987-01-01

    The following points stand out from a semi-open questionnaire which was sent to the parents of 28 children hospitalized for accidental intoxication. Intoxications often occur in children who are hyperactive, curious, rebellious and have strong affective needs. Parents find it very difficult to set bans and limitations to their children, whose behaviour seems to be actively calling out for such restrictions. These children frequently put themselves in a situation of self-aggression, which shows the parents' inability to teach them to develop a vital self protective attitude from life's daily experience. Most often, the child is aware of transgressing a ban and in a few cases, intoxication seems to be a deliberate act on his part. It generally occurs when stress has been building up in the family, thus threatening the balance of the family. If it happens in a family where relationships are already deeply disturbed, it must be considered as a signal of alarm. It is then necessary to suggest that the family should undergo a psychotherapeutic course to help them to put an end to the deadly process in which they are involved. PMID:3448592

  11. Quick management of accidental tritium exposure cases.

    PubMed

    Singh, Vishwanath P; Badiger, N M; Managanvi, S S; Bhat, H R

    2012-07-01

    Removal half-life (RHL) of tritium is one of the best means for optimising medical treatment, reduction of committed effective dose (CED) and quick/easy handling of a large group of workers for medical treatment reference. The removal of tritium from the body depends on age, temperature, relative humidity and daily rainfall; so tritium removal rate, its follow-up and proper data analysis and recording are the best techniques for management of accidental acute tritium exposed cases. The decision of referring for medical treatment or medical intervention (MI) would be based on workers' tritium RHL history taken from their bodies at the facilities. The workers with tritium intake up to 1 ALI shall not be considered for medical treatment as it is a derived limit of annual total effective dose. The short-term MI may be considered for tritium intake of 1-10 ALI; however, if the results show intake ≥100 ALI, extended strong medical/therapeutic intervention may be recommended based on the severity of exposure for maximum CED reduction requirements and annual total effective dose limit. The methodology is very useful for pressurized heavy water reactors (PHWRs) which are mainly operated by Canada and India and future fusion reactor technologies. Proper management will optimise the cases for medical treatment and enhance public acceptance of nuclear fission and fusion reactor technologies. PMID:22349318

  12. Accidental overdose of multiple chemotherapeutic agents.

    PubMed

    Kim, I S; Gratwohl, A; Stebler, C; Hausmann, M; Tichelli, A; Stern, A; Speck, B

    1989-07-01

    A 35-year-old man with refractory low grade diffuse centroblastic centrocytic non-Hodgkin's lymphoma was treated accidentally with an overdose of multiple chemotherapeutic agents. He was given adriamycin 50 mg/m2 and cyclophosphamide 350 mg/m2 for 6 days followed by 4 days of vincristine 1 mg/m2 and bleomycin 10 mg/m2. He was transferred when he developed pancytopenia, fever, severe mucositis, ileus and peripheral neuropathy. He was treated with broad spectrum antibiotics, red cell and single donor platelet transfusions and strict parenteral nutrition. In addition, he was given a continuous infusion of 400 micrograms daily human recombinant granulocyte macrophage-colony stimulating factor (rh GM-CSF) for 17 days. Intractable severe bleeding from his oral mucositis necessitated treatment with a continuous infusion of 8-ornithine-vasopressin for 8 days. He recovered and could be discharged home after 36 days of hospitalization with normal blood counts and without severe sequelae. PMID:2486848

  13. Accidental Overdose of Multiple Chemotherapeutic Agents

    PubMed Central

    Kim, In Soon; Gratwohl, A.; Stebler, C.; Hausmann, M.; Tichelli, A.; Stern, A.; Speck, B.

    1989-01-01

    A 35-year-old man with refractory low grade diffuse centroblastic centrocytic non-Hodgkin’s lymphoma was treated accidentally with an overdose of multiple chemotherapeutic agents. He was given adriamycin 50 mg/m2 and cyclophosphamide 350 mg/m2 for 6 days followed by 4 days of vincristine 1 mg/m2 and bleomycin 10 mg/m2. He was transferred when he developed pancytopenia, fever, severe mucositis, ileus and peripheral neuropathy. He was treated with broad spectrum antibiotics, red cell and single donor platelet transfusions and strict parenteral nutrition. In addition, he was given a continuous infusion of 400 ug daily human recombinant granulocyte macrophage-colony stimulating factor (rh GM-CSF) for 17 days. Intractable severe bleeding from his oral mucositis necessitated treatment with a continuous infusion of 8-ornithine-vasopressin for 8 days. He recovered and could be discharged home after 36 days of hospitalization with normal blood counts and without severe sequelae. PMID:2486848

  14. The Siberian Traps and the end-Permian event: Geology, geochemistry and atmospheric modeling of gas release

    NASA Astrophysics Data System (ADS)

    Svensen, Henrik; Stordal, Frode; Roscher, Marco; Sokalska, Ewa; Planke, Sverre

    2013-04-01

    The Siberian Traps were emplaces through sedimentary basins covering the Siberian Craton, passing thick accumulations of carbonates and evaporites. Contact metamorphism of the sedimentary rocks around dolerite sills and dikes generated greenhouse gases and halocarbons to such an extent that the process could be responsible for both the end-Permian carbon isotope excursion and the mass extinction. The key processes are suggested to be 1) metamorphism of oil-saturated rock salt sequences (halocarbon production), 2) methane generation from metamorphism of organic-rich shales (methane production), and 3) decarbonation of dolostones (carbon dioxide production). We have analyzed the petrography and geochemistry (including carbon isotopes) of contact metamorphic carbonates from outcrops, and can document the devolatilization processes. In addition, we have explored the potential global warming effects of CO2 and CH4 emissions to the end-Permian atmosphere from the volatile generation. We have constrained the effect of century scale degassing events using the atmospheric lifetime of CH4 and CO2, the pre-event atmospheric composition in terms of methane and carbon-dioxide as well as H2S, the gas flux to the atmosphere, the IR absorption efficiency, the radiative forcing and the climate sensitivity. Assuming rapid emplacement of one single major sill intrusion into the Tunguska Basin, and 100 year gas release with 60% CH4 and 40% CO2, the global annual mean temperature could rise by 2-5°C (best estimate ~3.5°C). In contrast, degassing from subaerial lava flows with the same magma volume as a sill has one order of magnitude lower influence on the global climate, resulting in a warming of about 0.1°C. Per molecule CH4 is much more efficient in absorbing and re-emitting IR radiation than CO2, yielding a much stronger greenhouse effect in the Earth's atmosphere. Considering that the heat trapped in the atmosphere over a 100 year period resulting from an emission of CH4 is

  15. Chemical release module facility

    NASA Technical Reports Server (NTRS)

    Reasoner, D. L.

    1980-01-01

    The chemical release module provides the capability to conduct: (1) thermite based metal vapor releases; (2) pressurized gas releases; (3) dispersed liquid releases; (4) shaped charge releases from ejected submodules; and (5) diagnostic measurements with pi supplied instruments. It also provides a basic R-F and electrical system for: (1) receiving and executing commands; (2) telemetering housekeeping data; (3) tracking; (4) monitoring housekeeping and control units; and (5) ultrasafe disarming and control monitoring.

  16. Complications in exodontia--accidental dislodgment to adjacent anatomical areas.

    PubMed

    Grandini, S A; Barros, V M; Salata, L A; Rosa, A L; Soares, U N

    1993-01-01

    The authors report 4 cases of accidental dislodgement of teeth to adjacent anatomical areas during extraction. The causes and their prevention are discussed and solutions for the problem are suggested. PMID:8241759

  17. Frequent detection of stomach contents in accidental drowning.

    PubMed

    Kibayashi, Kazuhiko; Shimada, Ryo; Nakao, Ken-Ichiro

    2011-07-01

    We analysed forensic autopsies of 536 consecutive adults to determine the relationship between the presence of stomach contents and the manner of death. Stomach contents were identified in 27 (79.4%) of 34 accidental drownings and in 22 (43.1%) of 51 suicidal drownings (P < 0.01). Accidental drowning was the manner of death most frequently associated with the presence of stomach contents, and stomach contents were found significantly more often in this type of death than in suicidal drowning. These findings indicate that food intake is a factor possibly related to accidental drowning and suggest that fasting may be required before swimming or taking a bath to prevent accidental drowning. PMID:21905572

  18. Accidental Childhood Iron Poisoning: A Problem of Marketing and Labeling.

    ERIC Educational Resources Information Center

    Krenzelok, Edward P.; Hoff, Julie V.

    1979-01-01

    The article indicates that accidental iron poisoning represents a significant hazard in children less than five years of age. Attractiveness of dosage, high availability, and ambiguity in product labeling contribute to the problem. Journal availability: see EC 114 125. (CL)

  19. [Retinal haemorrhages in non-accidental head injury in childhood].

    PubMed

    Oberacher-Velten, I M; Helbig, H

    2014-09-01

    Retinal haemorrhages are one of the three cardinal manifestations of the "shaken baby syndrome" or "non-accidental head injury" in childhood. The role of an ophthalmologist in suspected non-accidental head injury has not only medical but also legal aspects and has been discussed controversially in the literature. The differential diagnosis and the specificity of retinal haemorrhages in childhood for an abusive head trauma will be pointed out in this paper. PMID:25181505

  20. Pingos, craters and methane-leaking seafloor in the central Barents Sea: signals of decomposing gas hydrate releasing gas from deeper hydrocarbon reservoirs?

    NASA Astrophysics Data System (ADS)

    Andreassen, K.; Plaza-Faverola, A. A.; Winsborrow, M.; Deryabin, A.; Mattingsdal, R.; Vadakkepuliyambatta, S.; Serov, P.; Mienert, J.; Bünz, S.

    2015-12-01

    A cluster of large craters and mounds appear on the gas-leaking sea floor in the central Barents Sea around the upper limit for methane hydrate stability, covering over 360 km2. We use multibeam bathymetry, single-beam echo sounder and high-resolution seismic data to reveal the detailed geomorphology and internal structure of craters and mounds, map the distribution gas in the water and to unravel the subsurface plumbing system and sources of gas leakage. Distinct morphologies and geophysical signatures of mounds and craters are inferred to reflect different development stages of shallow gas hydrate formation and dissociation. Over 600 gas flares extending from the sea floor into the water are mapped, many of these from the seafloor mounds and craters, but most from their flanks and surroundings. Analysis of geophysical data link gas flares in the water, craters and mounds to seismic indications of gas advection from deeper hydrocarbon reservoirs along faults and fractures. We present a conceptual model for formation of mounds, craters and gas leakage of the area.

  1. Infrasonic signals from an accidental chemical explosion

    SciTech Connect

    Mutschlecner, J.P.; Whitaker, R.W.

    1996-12-31

    A series of large accidental explosions occurred at a chemical plant in Henderson, Nevada on May 4, 1988. The explosions were produced by the ignition of stores of ammonium perchlorate produced for solid rocket fuel at the Pacific Engineering and Production Co. This material, prior to the incident, had been believed to be non- explosive. The blasts destroyed the plant and caused one death. There was a series of explosions over a period of time with two major explosions which we will identify as A at 18:53:34 (all times herein will be given in C.U.T.) and B at 18:57:35. Signals from events A and B as well as smaller events were detected by the infrasound arrays operated by the Los Alamos National Laboratory at St. George, Utah (distance 159 km) and at Los Alamos, N.M. (distance 774 km). The Henderson explosions present an interesting and challenging set of infrasound observations. The case may be unique in providing two very large sources separated in time by only four minutes. To fully understand the propagation details will require further analysis and probably a modeling effort. The understanding of the St. George signals in the context of Lamb waves would be valuable for a better understanding of this mode of propagation. The improved understanding of long range infrasonic propagation is now especially important in the context of the Comprehensive Test Ban Treaty (CTBT). A portion of the plan for CTBT monitoring includes a global distribution of sixty infrasound arrays to provide for the monitoring of signals in as uniform a way as possible. It is expected that under this global network many signals and interpretation questions of the type described here will be encountered. Investigations of propagation over the ranges of hundreds to thousands of kilometers will be highly desired.

  2. Some effects of gas adsorption on the high temperature volatile release behavior of a terrestrial basalt, tektite and lunar soil

    NASA Technical Reports Server (NTRS)

    Graham, D. G.; Muenow, D. W.; Gibson, E. K., Jr.

    1979-01-01

    Mass pyrograms obtained from high-temperature, mass psectrometric pyrolysis of a glassy theoleiitic submarine basalt and a tektite, ground in air to less than 64 microns, have shown N2 and SO release patterns very similar to those from the pyrolysis of mature lunar soil fines. The N2 and CO release behavior from the terrestrial samples reproduces the biomodal, high-temperature (approximately 700 and 1050 C) features from the lunar samples. Unground portions of the basalt and tektite show no release of N2 and CO during pyrolysis. Grinding also alters the release behavior and absolute amounts of H2O and CO2. It is suggested that adsorption of atmospheric gases in addition to solar wind implantation of ions may account for the wide range of values in previously reported concentrations of carbon and nitrogen from lunar fines.

  3. Epidemiology of Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation.

    PubMed Central

    McClure, R J; Davis, P M; Meadow, S R; Sibert, J R

    1996-01-01

    A two year prospective study was performed to determine the epidemiology of Munchausen syndrome by proxy, non-accidental poisoning, and non-accidental suffocation in the UK and the Republic of Ireland. Cases were notified to the British Paediatric Association Surveillance Unit from September 1992 to August 1994 if a formal case conference had been held for the first time during that period to discuss any of the above conditions. A total of 128 cases were identified: 55 suffered Munchausen syndrome by proxy alone, 15 poisoning, and 15 suffocation; 43 suffered more than one type of abuse. The majority of children were aged under 5 years, the median age being 20 months. On 85% of occasions the perpetrator was the child's mother. In 42% of families with more than one child, a sibling had previously suffered some form of abuse. Eighty five per cent of notifying paediatricians considered the probability of their diagnosis as virtually certain before a case conference was convened. The commonest drugs used to poison were anticonvulsants; opiates were the second commonest. Sixty eight children suffered severe illness of whom eight died. The combined annual incidence of these conditions in children aged under 16 years is at least 0.5/100,000, and for children aged under 1, at least 2.8/100,000. PMID:8813872

  4. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL) Part 1. Description of Tritium Dose Model (DCART) for Routine Releases from LLNL

    SciTech Connect

    Peterson, S R

    2006-09-27

    DCART (Doses from Chronic Atmospheric Releases of Tritium) is a spreadsheet model developed at Lawrence Livermore National Laboratory (LLNL) that calculates doses from inhalation of tritiated hydrogen gas (HT), inhalation and skin absorption of tritiated water (HTO), and ingestion of HTO and organically bound tritium (OBT) to adult, child (age 10), and infant (age 6 months to 1 year) from routine atmospheric releases of HT and HTO. DCART is a deterministic model that, when coupled to the risk assessment software Crystal Ball{reg_sign}, predicts doses with a 95% confidence interval. The equations used by DCART are described and all distributions on parameter values are presented. DCART has been tested against the results of other models and several sets of observations in the Tritium Working Groups of the International Atomic Energy Agency's programs, Biosphere Modeling and Assessment and Environmental Modeling for Radiation Safety. The version of DCART described here has been modified to include parameter values and distributions specific to conditions at LLNL. In future work, DCART will be used to reconstruct dose to the hypothetical maximally exposed individual from annual routine releases of HTO and HT from all LLNL facilities and from the Sandia National Laboratory's Tritium Research Laboratory over the last fifty years.

  5. Real-time monitoring of fragrance release from cotton towels by low thermal mass gas chromatography using a longitudinally modulating cryogenic system for headspace sampling and injection.

    PubMed

    Haefliger, Olivier P; Jeckelmann, Nicolas; Ouali, Lahoussine; León, Géraldine

    2010-01-15

    An innovative headspace sampling and injection system for gas chromatography was designed using a longitudinally modulating cryogenic system mounted around the sampling loop of a two-position loop injector. The setup was hyphenated to a fast low thermal mass gas chromatograph, allowing transient concentrations of semivolatile analytes to be monitored in real time with a time resolution of 4.5 min. The performance of the instrument, and in particular its cryotrapping efficiency, was characterized using a mixture of long-chain alkanes, methyl esters, ethyl esters, and alcohols of different volatilities. The device was found to be ideally suited to the analysis of semivolatile compounds with boiling points ranging between 190 and 320 degrees C, which are typical for a majority of perfumery raw materials. The new instrument was successfully used to monitor the release of eight odorant compounds from cotton towels to which fabric softener had been applied that alternatively contained the fragrance in free form or in microencapsulated form. The analytical results, unprecedented in their level of precision and time resolution for such an application, evidenced the major impact of microencapsulation technology on the kinetics of fragrance release during the drying of the towels and on the triggering of additional fragrance release by applying mechanical stress to the fabric to rupture the microcapsule walls. PMID:20025230

  6. Evaluation of ursodeoxycholic acid bioavailability from immediate- and sustained-release preparations using gas chromatography-mass spectrometry and high-performance liquid chromatography.

    PubMed

    Scalia, S; Scagliarini, R; Pazzi, P

    2000-02-01

    An improved procedure is presented for the determination of ursodeoxycholic acid (CAS 128-13-2, UDCA) in human plasma and bile after oral administration of UDCA-containing dosage forms. The plasma samples after solid-phase extraction with silica-based C18- and strong anion exchange cartridges were assayed by gas chromatography-mass spectrometry (GC-MS) using selected-ion monitoring. The hexafluoroisopropyl trifluoroacetate ester derivative of UDCA was selected for GC analysis since it is easily and rapidly prepared by a one-step reaction. Biliary UDCA levels were determined by a rapid and simple high-performance liquid chromatographic (HPLC) method with on-line sample purification. This analytical protocol was used to investigate the pharmacokinetic of a new sustained-release capsule of UDCA in comparison with a reference immediate-release preparation after single oral administration. Statistical evaluation of the area under the plasma concentration-time curves indicated that two formulations are equivalent with regard to the amount of drug absorbed. However, pharmacokinetic data showed that with the sustained-release preparation a significantly delayed mean peak plasma level was reached compared with the reference preparation. Moreover, the immediate- and extended-release capsules were found to achieve a comparable degree of biliary enrichment with UDCA. PMID:10719615

  7. [Severe accidental hypothermia in an elderly woman].

    PubMed

    Knobel, B; Mikhlin, A

    2001-11-01

    Profound hypothermia (core temperature of less than 28 degrees C) is a life threatening state and a medical emergency associated with a high mortality rate. The prognosis depends on underlying diseases, advanced or very early age, the duration prior to treatment, the degree of hemodynamic deterioration, and especially, the methods of treatment, including active external or internal rewarming. This is a case study of an 80-year-old female patient with severe accidental hypothermia (core temperature 27 degrees C). She was found in her home lying immobile on the cold floor after a fall. The patient was in a profound coma with cardiocirculatory collapse, and the medical staff treating her was inclined to pronounce her deceased. On her arrival at the hospital, she was resuscitated, put on a respirator and actively warmed. Very severe metabolic disorders were found, including a marked metabolic acidosis composed of diabetic ketoacidosis (she had suffered from insulin treated type 2 diabetes mellitus) and lactic acidosis with a very high anion gap (42) and a hyperosmotic state (blood glucose 1202 mg/dl). There were pathognomonic electrocardiographic abnormalities, J-wave of Osborn and prolonged repolarization. Slow atrial fibrillation with a ventricular response of 30 bpm followed by a nodal rhythm of 12 bpm and reversible cardiac arrest were recorded. The pulse and blood pressure were unobtainable. Despite the successful resuscitation and hemodynamic and cognitive improvement, rhabdomyolysis (CKP 6580 u/L), renal failure and hepatic damage developed. She was extubated and treated with intravenous fluids containing dopamine, bicarbonate, insulin and antibiotics. Her medical condition gradually improved, and she was discharged clear minded, functioning very well and independent. Renal and liver tests returned eventually to normal limits. Progressive bradycardia, hypotension and death due to ventricular fibrillation or asystole commonly occur during severe hypothermia

  8. Graphite corrosion and hydrogen release from HTR fuel elements in Q-brine

    SciTech Connect

    Fachinger, J.; Zhang, Z.X.; Brodda, B.G.

    1995-12-31

    Industrial reprocessing for High Temperature Reactors (HTR) fuel elements has never been installed in Germany. The spent fuel elements are being considered for final disposal in a rock salt repository in the deep geologic underground. Safety analysis requires the assumption of an accidental water ingress into the repository, resulting in the formation of a concentrated salt solution with the typical composition of a quinary brine. After corrosive penetration of the container walls, the brine may finally contact the fuel elements directly and mobilize radionuclides. Duve et al. investigated the leaching of the fission products and actinides from HTR fuel elements in Q-brine. The mobilization of {sup 14}C by graphite corrosion is one of the last data bases required as a source term for the release estimation of radionuclides in the final safety analysis. The evaluation of the hydrogen release was prescribed by the licensing board, because an excessive gas pressure may affect the overall integrity of the geological barrier. {sup 14}C occurs as dissolved organic and inorganic compounds in the brine. The leaching rate or organic {sup 14}C decreases from about 80 Bq to 1 Bq. The amount of organic {sup 14}C decreases from about 80 Bq to 1 Bq during leaching. The release of inorganic {sup 14}C ceases within 4 months. About 100 ppm of the total {sup 14}C inventory was released during leaching. Gaseous {sup 14}C has never been detected. The gas formation is based on the radiolytic degradation of water, with a formation rate of 0.04 to 0.11 ml/d. Gas chromatographic analysis of the gas proved that hydrogen is the main component of the released gas. Tritium and {sup 85}Kr were detected as traces with radio gas chromatography.

  9. Cost of accidental carbon monoxide poisoning: A preventable expense.

    PubMed

    Hampson, Neil B

    2016-06-01

    Carbon monoxide (CO) poisoning is common in the United States, accounting for hundreds of deaths and thousands of emergency department visits annually. It is believed that most accidental CO poisoning is preventable through public education, warning labels on consumer products, and uniform use of residential CO alarms. However, cost effectiveness of these prevention strategies has not been demonstrated in the United States to date. It was the objective of this study to estimate societal cost of accidental CO poisoning and evaluate the cost-effectiveness of universal installation of residential CO alarms. Published studies and data from the English language literature were used in to estimate direct hospital costs and lost earnings resulting from accidental CO poisoning. The study was performed in the US in 2015. Approximately 6600 individuals are estimated to sustain long-term cognitive sequela annually, with total loss in earnings of approximately $925 million, 334 individuals die from accidental, non-fire related CO poisoning with an average loss of 26 years of productivity accounting for $355 million, and 2800 are hospitalized with acute medical care costs of $33 million. Available data indicate that accidental CO poisoning in the US conservatively costs society over $1.3 billion, resulting from direct hospital costs and lost earnings. Further, it demonstrates a positive cost-benefit ratio for the uniform use of residential CO alarms. PMID:26844181

  10. Cost of accidental carbon monoxide poisoning: A preventable expense

    PubMed Central

    Hampson, Neil B.

    2015-01-01

    Carbon monoxide (CO) poisoning is common in the United States, accounting for hundreds of deaths and thousands of emergency department visits annually. It is believed that most accidental CO poisoning is preventable through public education, warning labels on consumer products, and uniform use of residential CO alarms. However, cost effectiveness of these prevention strategies has not been demonstrated in the United States to date. It was the objective of this study to estimate societal cost of accidental CO poisoning and evaluate the cost-effectiveness of universal installation of residential CO alarms. Published studies and data from the English language literature were used in to estimate direct hospital costs and lost earnings resulting from accidental CO poisoning. The study was performed in the US in 2015. Approximately 6600 individuals are estimated to sustain long-term cognitive sequela annually, with total loss in earnings of approximately $925 million, 334 individuals die from accidental, non-fire related CO poisoning with an average loss of 26 years of productivity accounting for $355 million, and 2800 are hospitalized with acute medical care costs of $33 million. Available data indicate that accidental CO poisoning in the US conservatively costs society over $1.3 billion, resulting from direct hospital costs and lost earnings. Further, it demonstrates a positive cost-benefit ratio for the uniform use of residential CO alarms. PMID:26844181

  11. Gas chromatography using a resistively heated column with mass spectrometric detection for rapid analysis of pyridine released from Bacillus spores.

    PubMed

    Smith, Philip A; MacDonald, Stephen

    2004-05-21

    Gas chromatography using a resistively heated analytical column with full scan electron impact mass spectrometry (EI-MS) was used to detect pyridine generated from heating Bacillus spores in a custom designed furnace inlet, along with gasoline range aromatic (GRA) hydrocarbons representing an environmental contaminant that could interfere with detection of the biologically-derived compound. Gas phase materials from the furnace inlet were collected onto a section of cooled open tubular column, and carrier gas flow was then routed through the trapping column onto the analytical column. Both sections of column were contained within low thermal mass tubular metal sheaths, with each independently and resistively heated allowing rapid temperature ramps and cooling. An analysis time of 2 min resolved spore-derived pyridine from the other organics, and allowed identification by mass spectrum match. Throughput of 20 analyses per hour was shown to be possible with a 1-min column cool-down time between analyses. PMID:15146930

  12. Ingestion Pathway Consequences of a Major Release from SRTC

    SciTech Connect

    Blanchard, A.

    1999-06-08

    The food ingestion consequences due to radioactive particulates of an accidental release, scenario 1-RD-3, are evaluated for Savannah River Technology Center. The sizes of land areas requiring the protective action of food interdiction are calculated. The consequences of the particulate portion of the release are evaluated with the HOTSPOT model and an EXCEL spreadsheet for particulates.

  13. Measuring in situ dissolved methane concentrations in gas hydrate-rich systems, Part 1: Investigating the correlation between tectonics and methane release from sediments

    NASA Astrophysics Data System (ADS)

    Lapham, L.; Wilson, R. M.; Paull, C. K.; Chanton, J.; Riedel, M.

    2010-12-01

    In 2009, an area of extended methane venting at 1200 meters water depth was found with high resolution AUV bathymetry scans on the Northern Cascadia Margin that was previously unknown. When visited by ROV, we found seafloor cracks with active bubble streams and thin bacterial mats suggesting shallow gas and possible pore-fluid saturation. Upon coring into the cracks, a hard-substrate (carbonate or gas hydrate) was punctured and gas flows began. With these observations, we asked the question “is this shallow gas released from the seafloor from regional tectonic activity, and, if so, what is the temporal variability of such release events?” To answer this, we deployed a long term pore-water collection device at one of these gas crack sites, informally named “bubbly gulch”, for 9 months. The device is made up of 4 OsmoSamplers that were each plumbed to a port along a 1-meter probe tip using small diameter tubing. By osmosis, the samplers collected water samples slowly through the ports and maintained them within a 300 meter-long copper tubing coil. Because of the high methane concentrations anticipated, in situ pressures were maintained within the coil by the addition of a high pressure valve. Water samples were collected from the overlying water, at the sediment-water interface, and 6 and 10 cm into the sediments. Bottom water temperatures were also measured over the time series to determine pumping rates of the samplers but also to look for any temporal variability. In May 2010, the samplers were retrieved by ROV during efforts to install seafloor instruments for Neptune Canada. In a land-based lab, the coils were sub-sampled by cutting every 4 meters of tubing. With a pumping rate of 0.5 mL/day, this allowed a temporal resolution of 6 days. To date, one sampler coil has been sub-sampled and measured for methane concentrations and stable carbon isotopes. Preliminary results from this coil show pore-fluids nearly saturated with respect to methane, ~45 m

  14. The secondary release of mercury in coal fly ash-based flue-gas mercury removal technology.

    PubMed

    He, Jingfeng; Duan, Chenlong; Lei, Mingzhe; Zhu, Xuemei

    2016-01-01

    The secondary release of mercury from coal fly ash is a negative by-product from coal-fired power plants, and requires effective control to reduce environmental pollution. Analysing particle size distribution and composition of the coal fly ash produced by different mercury removing technologies indicates that the particles are generally less than 0.5 mm in size and are composed mainly of SiO2, Al2O3, and Fe2O3. The relationships between mercury concentration in the coal fly ash, its particle size, and loss of ignition were studied using different mercury removing approaches. The research indicates that the coal fly ash's mercury levels are significantly higher after injecting activated carbon or brominating activated carbon when compared to regular cooperating-pollution control technology. This is particularly true for particle size ranges of >0.125, 0.075-0.125, and 0.05-0.075 mm. Leaching experiments revealed the secondary release of mercury in discarded coal fly ash. The concentration of mercury in the coal fly ash increases as the quantity of injecting activated carbon or brominating activated carbon increases. The leached concentrations of mercury increase as the particle size of the coal fly ash increases. Therefore, the secondary release of mercury can be controlled by adding suitable activated carbon or brominating activated carbon when disposing of coal fly ash. Adding CaBr2 before coal combustion in the boiler also helps control the secondary release of mercury, by increasing the Hg(2+) concentration in the leachate. This work provides a theoretical foundation for controlling and removing mercury in coal fly ash disposal. PMID:26121324

  15. Self limiting features of accidental criticality in a solution system

    SciTech Connect

    Malenfant, R.E.

    1988-01-01

    Experience with the SHEBA solution critical assembly during validation testing of accidental criticality alarm detectors provided several insights into the character of potential accidental excursions. Two observations were of particular interest. First, it is nearly impossible to maintain a solution system, particularly one employing low-enrichment material, in a constant state. If super-critical, the system will heat up, expand (or form bubbles), return to a sub-critical state, and shut down of its own accord without going into short period oscillations. Second, a very slow change in the system could produce a long ''pulse'' resulting in lengthy exposures, a high dose, but a low dose rate. The experiments dramatically contradicted the popular contention that accidental criticality is characterized by a blue flash, a clap of thunder, and violet expulsion of material. 5 refs., 3 figs., 4 tabs.

  16. Advanced radiometric complex for detection of radioactive release from Siberian chemical combine

    NASA Astrophysics Data System (ADS)

    Kolotkov, Gennady A.; Penin, Sergei T.

    2015-11-01

    The paper states limited availability of the use of the automated radiation situation monitoring system and proposes radiometric complex as more reliable system in the case of an accidental release of the Siberian Chemical Enterprises.

  17. A Possible Organic Contribution to the Low Temperature CO2 Release Seen in Mars Phoenix Thermal and Evolved Gas Analyzer Data

    NASA Technical Reports Server (NTRS)

    Archer, P. D. Jr.; Lauer, H. V., Jr.; Sutter, B.; Ming, D. W.; Niles, P. B.; Boynton, W. V.

    2012-01-01

    Two of the most important discoveries of the Phoenix Mars Lander were the discovery of approx.0.6% perchlorate [1] and 3-5% carbonate [2] in the soils at the landing site in the martian northern plains. The Thermal and Evolved Gas Analyzer (TEGA) instrument was one of the tools that made this discovery. After soil samples were delivered to TEGA and transferred into small ovens, the samples could be heated up to approx.1000 C and the gases that evolved during heating were monitored by a mass spectrometer. A CO2 signal was detected at high temperature (approx.750 C) that has been attributed to calcium carbonate decomposition. In addition to this CO2 release, a lower temperature signal was seen. This lower temperature CO2 release was postulated to be one of three things: 1) desorption of CO2, 2) decomposition of a different carbonate mineral, or 3) CO2 released due to organic combustion. Cannon et al. [3] present another novel hypothesis involving the interaction of decomposition products of a perchlorate salt and calcium carbonate.

  18. Evidence for faulting related to dissociation of gas hydrate and release of methane off the southeastern United States

    USGS Publications Warehouse

    Dillon, William P.; Danforth, W.W.; Hutchinson, D.R.; Drury, R.M.; Taylor, M.H.; Booth, J.S.

    1998-01-01

    This paper is part of the special publication Gas hydrates: relevance to world margin stability and climatic change (eds J.P. Henriet and J. Mienert). An irregular, faulted, collapse depression about 38 x 18 km in extent is located on the crest of the Blake Ridge offshore from the south- eastern United States. Faults disrupt the sea floor and terminate or sole out about 40-500 m below the sea floor at the base of the gas hydrate stable zone, which is identified from the location of the bottom simulating reflection (BSR). Normal faults are common but reverse faults and folds also are widespread. Folds commonly convert upward into faults. Sediment diapirs and deposits of sediments that were erupted onto the sea floor are also present. Sea-floor depressions at faults may represent locations of liquid/gas vents. The collapse was probably caused by overpressures and by the decoupling of the overlying sediments by gassy muds that existed just beneath the zone of gas hydrate stability.

  19. Scaling and gender behavior of road accidental dynamics

    NASA Astrophysics Data System (ADS)

    Qiu, Tian; Zou, Xiang-Xiang; Chen, Guang; Jiang, Xiong-Fei; Zhong, Li-Xin

    2014-12-01

    The probability distribution of the time intervals between two consecutive accidents is investigated, based on the road accidental records of the Great Britain. A universal description is obtained for different roads, by rescaling the probability distribution and time intervals. The scaling curve is found to deviate from the Gaussian distribution, but it is well fitted by a stretched exponential function. Long-range time correlation is revealed for the interevent series. Moreover, gender similarity is found for the small accidental intervals, while for the large intervals, the female drivers are observed to present a higher probability than the male drivers.

  20. Accidental ingestion of a fractured Twin-block appliance.

    PubMed

    Rohida, Neeraj S; Bhad, Wasundhara A

    2011-01-01

    Orthodontic appliances that become dislodged can cause problems in the airway or the gastrointestinal tract. Accidental ingestion of an appliance during a chair-side procedure or because of inadequate retention of the appliance can create a medical emergency with potentially serious complications, including death from aspiration of the foreign body. This article reports the accidental ingestion of a fractured Twin-block appliance. The ease with which removable appliances can become dislodged if retention is inadequate is discussed, and some serious complications that can arise are described. Precautions the orthodontist can take to prevent such accidents are presented. PMID:21195285

  1. STEADY-STATE FLAMMABLE GAS RELEASE RATE CALCULATION AND LOWER FLAMMABILITY LEVEL EVALUATION FOR HANFORD TANK WASTE

    SciTech Connect

    HU TA

    2007-10-26

    Assess the steady-state flammability level at normal and off-normal ventilation conditions. The methodology of flammability analysis for Hanford tank waste is developed. The hydrogen generation rate model was applied to calculate the gas generation rate for 177 tanks. Flammability concentrations and the time to reach 25% and 100% of the lower flammability limit, and the minimum ventilation rate to keep from 100 of the LFL are calculated for 177 tanks at various scenarios.

  2. EFFECTS OF ALTERNATE ANTIFOAM AGENTS, NOBLE METALS, MIXING SYSTEMS AND MASS TRANSFER ON GAS HOLDUP AND RELEASE FROM NONNEWTONIAN SLURRIES

    SciTech Connect

    Guerrero, H; Mark Fowley, M; Charles Crawford, C; Michael Restivo, M; Robert Leishear, R

    2007-12-24

    Gas holdup tests performed in a small-scale mechanically-agitated mixing system at the Savannah River National Laboratory (SRNL) were reported in 2006. The tests were for a simulant of waste from the Hanford Tank 241-AZ-101 and featured additions of DOW Corning Q2-3183A Antifoam agent. Results indicated that this antifoam agent (AFA) increased gas holdup in the waste simulant by about a factor of four and, counter intuitively, that the holdup increased as the simulant shear strength decreased (apparent viscosity decreased). These results raised questions about how the AFA might affect gas holdup in Hanford Waste Treatment and Immobilization Plant (WTP) vessels mixed by air sparging and pulse-jet mixers (PJMs). And whether the WTP air supply system being designed would have the capacity to handle a demand for increased airflow to operate the sparger-PJM mixing systems should the AFA increase retention of the radiochemically generated flammable gases in the waste by making the gas bubbles smaller and less mobile, or decrease the size of sparger bubbles making them mix less effectively for a given airflow rate. A new testing program was developed to assess the potential effects of adding the DOW Corning Q2-3183A AFA to WTP waste streams by first confirming the results of the work reported in 2006 by Stewart et al. and then determining if the AFA in fact causes such increased gas holdup in a prototypic sparger-PJM mixing system, or if the increased holdup is just a feature of the small-scale agitation system. Other elements of the new program include evaluating effects other variables could have on gas holdup in systems with AFA additions such as catalysis from trace noble metals in the waste, determining mass transfer coefficients for the AZ-101 waste simulant, and determining whether other AFA compositions such as Dow Corning 1520-US could also increase gas holdup in Hanford waste. This new testing program was split into two investigations, prototypic sparger

  3. Accidental discharge of a Halon 1301 total flooding fire extinguishing system

    SciTech Connect

    Sass-Kortsak, A.M.; Holness, D.L.; Stopps, G.J.

    1985-11-01

    An accidental discharge of a total flooding Halon 1301 fire extinguishing system is described. The release of the Halon was accompanied by a sudden very loud noise, considerable air turbulence and a dense fog, resulting in worker anxiety and loss of visibility. The workers in the area at the time of the discharge reported higher frequencies of lightheadedness, headache, nasal complaints and disorientation than those entering the area later. Halon 1301 usually is regarded as having a low toxicity, although at concentrations above those used in occupied spaces, effects on consciousness and cardiac rhythm have been reported. In the present report no significant illness or injury due to the Halon exposure was found. A fine oily deposit found on horizontal surfaces in the area subsequent to the discharge consisted of mineral oil and iron, suggesting that this material was scoured out of the piping as the Halon discharged. The disorientation and anxiety produced by an accidental discharge can be minimized through education programs designed to ensure that personnel know what to expect and how to abort the discharge if it results from a false alarm. Situations leading to triggering of fire detectors by events other than fires should be investigated and reduced.

  4. Accidental contamination of a German town's drinking water with sodium hydroxide.

    PubMed

    Lendowski, Luba; Färber, Harald; Holy, Andreas; Darius, Anke; Ehrich, Bernd; Wippermann, Christine; Küfner, Bernd; Exner, Martin

    2015-05-01

    Case report of a very serious drinking water incident putting up to 50,000 inhabitants of a town near Bonn in North Rhine-Westphalia, Germany at risk. A concentrated solution of highly alkaline water by sodium hydroxide was accidentally washed into the town's drinking water at a pumping station and increased the pH-value of the water to 12. Residents who came into contact with the contaminated water immediately had a toxic reaction. The incident was detected by complaints from customers and after that was stopped within several hours. The pipes were flushed and the customers were warned not to use the water till the all clear. After this immediate management there was an investigation and the cause of the incident was detected as an accidental release of accumulated sodium hydroxide (NaOH) solution. The lack of a network alarm system and the automatic cut-off mechanisms as deficiencies in the design of the station were rectified by the water company immediately after the incident. PMID:25687345

  5. The footprint of CO2 leakage in the water-column: Insights from numerical modeling based on a North Sea gas release experiment

    NASA Astrophysics Data System (ADS)

    Vielstädte, L.; Linke, P.; Schmidt, M.; Sommer, S.; Wallmann, K.; McGinnis, D. F.; Haeckel, M.

    2013-12-01

    Assessing the environmental impact of potential CO2 leakage from offshore carbon dioxide storage sites necessitates the investigation of the corresponding pH change in the water-column. Numerical models have been developed to simulate the buoyant rise and dissolution of CO2 bubbles in the water-column and the subsequent near-field dispersion of dissolved CO2 in seawater under ocean current and tidal forcing. In order to test and improve numerical models a gas release experiment has been conducted at 80 m water-depth within the Sleipner area (North Sea). CO2 and Kr (used as inert tracer gas) were released on top of a benthic lander at varying gas flows (<140 kg/day) and bubble sizes (de: 1-6 mm). pCO2 and pH were measured by in situ sensors to monitor the spread of the solute in different vertical heights and distances downstream of the artificial leak. The experiment and numerical analysis show that the impact of such leakage rates is limited to the near-field bottom waters, due to the rapid dissolution of CO2 bubbles in seawater (CO2 is being stripped within the first two to five meters of bubble rise). In particular, small bubbles, which will dissolve close to the seafloor, may cause a dangerous low-pH environment for the marine benthos. However, on the larger scale, the advective transport by e.g. tidal currents, dominates the CO2 dispersal in the North Sea and dilutes the CO2 peak quickly. The model results show that at the small scales (<100 m) of the CO2 plume the lateral eddy diffusion (~0.01 m2/s) has only a negligible effect. Overall, we can postulate that CO2 leakage at a rate of ~ 100 kg per day as in our experiment will only have a localized impact on the marine environment, thereby reducing pH substantially (by 0.4 units) within a diameter of less than 50 m around the release spot (depending on the duration of leakage and the current velocities). Strong currents and tidal cycles significantly reduce the spreading of low-pH water masses into the far

  6. Experimental and numerical study of heavy gas dispersion in a ventilated room.

    PubMed

    Ricciardi, Laurent; Prévost, Corinne; Bouilloux, Laurent; Sestier-Carlin, Roger

    2008-04-01

    In order to better evaluate the consequences of an accidental release of heavy gas, such as uranium hexafluoride (UF(6)), in some installations in the nuclear fuel cycle, an experimental and numerical study was conducted by IRSN on heavy gas dispersion in a ventilated room. This study was based on about 20 injection configurations of a large quantity of a heavy tracer gas, sulphur hexafluoride (SF(6)), inside two ventilated rooms of different sizes. Stratification of the tracer gas was detected in all the configurations studied, even at low concentrations. Numerical simulations performed with the multidimensional CFX code enabled the stratification and the concentration levels reached in the rooms to be predicted overall, and the higher the air flow rate, the more satisfactory the comparison between simulation and experiment. PMID:17804157

  7. Key-locked guard prevents accidental switch actuation

    NASA Technical Reports Server (NTRS)

    Hawthorne, K. C.

    1966-01-01

    Switch guard, which locks in place on a panel, protects individual switches from accidental activation. The guard consists of a cup to cover the switch lever, a standard screw lock tumbler, and a stud that mates with a threaded adapter in the panel.

  8. Are diabetic foot lesions precipitated by accidental trauma?

    PubMed

    Doshi, H K; Moissinac, K; Harwant, S

    2001-12-01

    Diabetic foot lesions may arise from frictional trauma due to tight or inappropriate footwear, repetitive stresses on parts of the foot, overlying bony prominence generated by walking and accidental trauma to the neuropathic foot. Many diabetics have been found to be unaware of their foot lesion, or know what the precipitating cause was. Based on the assumption that accidental trauma would affect the foot in a random fashion and result in lesions distributed evenly throughout the foot, a study was performed to determine whether foot lesions were distributed evenly or concentrated to certain areas of predilection. It was found that foot lesions were not evenly distributed but concentrated to certain areas of predilection. Even though relatively high proportion of the study population walked about in open slippers and barefeet, the study showed that accidental trauma was not a predominant precipitant of diabetic foot lesions. Diabetic foot lesions tend to occur as a result of cumulative, repetitive trauma to areas of prediliection rather than accidental trauma. PMID:14569763

  9. The Accidental Transgressor: Morally Relevant Theory of Mind

    PubMed Central

    Killen, Melanie; Mulvey, Kelly Lynn; Richardson, Cameron; Jampol, Noah

    2014-01-01

    To test young children’s false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N = 162) at 3.5, 5.5, and 7.5 years of age were administered 3 tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an “accidental transgressor” task, which measured a morally relevant false belief theory of mind (MoToM). Children who did not pass false belief ToM were more likely to attribute negative intentions to an accidental transgressor than children who passed false belief ToM, and to use moral reasons when blaming the accidental transgressor. In Experiment 2, children (N = 46) who did not pass false belief ToM viewed it as more acceptable to punish the accidental transgressor than did participants who passed false belief ToM. Findings are discussed in light of research on the emergence of moral judgment and theory of mind. PMID:21377148

  10. Accidental entrapment of cats in front-loading washing machines

    PubMed Central

    Stewart, Sarah A.; Gaunt, Matthew C.; Taylor, Susan M.; Snead, Elizabeth C.R.

    2010-01-01

    Two clinical cases of accidental entrapment of cats in front-loading washing machines are described. One cat died the day after presentation as a result of aspiration pneumonia and head trauma, despite supportive care. The second cat survived with supportive treatment, but developed dermatologic complications 10 d later. PMID:21119868

  11. The Accidental Transgressor: Morally-Relevant Theory of Mind

    ERIC Educational Resources Information Center

    Killen, Melanie; Mulvey, Kelly Lynn; Richardson, Cameron; Jampol, Noah; Woodward, Amanda

    2011-01-01

    To test young children's false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N=162) at 3.5, 5.5, and 7.5 years of age were administered three tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an "accidental transgressor" task, which measured a…

  12. Accidental Childhood Poisoning in Enugu, South-East, Nigeria

    PubMed Central

    Edelu, BO; Odetunde, OI; Eke, CB; Uwaezuoke, NA; Oguonu, T

    2016-01-01

    Background: Accidental childhood poisoning is one of the recognized causes of morbidity and mortality in children under the age of 5 years worldwide. The prevalence and type of substance ingested vary from place to place and over time. Aim: This study was conducted with the aim of ascertaining the frequency and pattern of accidental childhood poisoning in Enugu. Subjects and Methods: This retrospective study was conducted at the Emergency Paediatric Unit of the University of Nigeria Teaching Hospital, Enugu, South-East, Nigeria from January 2003 to December 2012 (10 years). All the cases of childhood accidental poisoning that presented within the period were reviewed and important information extracted. Results: Sixty-five cases of childhood poisoning were recorded during the 10-year period, giving an incidence rate of 442 per 100,000 children. The mean age was 22.15 ± 11.7 months. Male:female ratio was 1.5:1. The prevalence was higher among those with low socioeconomic background. Kerosene poisoning was the most common agent. The overall mortality rate was 3.1% (2/65). Conclusion: Accidental childhood poisoning is common in Enugu, with appreciable mortality, with kerosene being the most common agent. We advocate regulatory policy on proper ways of storing kerosene and other harmful household chemicals and medications. PMID:27398248

  13. Homicide by methane gas.

    PubMed

    De-Giorgio, Fabio; Grassi, Vincenzo M; Vetrugno, Giuseppe; Rossi, Riccardo; Fucci, Nadia; d'Aloja, Ernesto; Pascali, Vincenzo L

    2012-09-10

    Methane is a suffocating gas, and "methane deaths" are largely the result of suffocation by gas-air displacement after accidental or deliberate exposure. Neither methane gas nor other suffocating gases are a common means of homicide, with the potential exception of the use of gas in chemical weapons or gas chambers. Here, we report the case of a 53-year-old woman who was killed by her husband with methane gas. The man had given his wife a dose of Lorazepam before setting up a hose that conveyed methane from the kitchen into the apartment's bedroom. The man subsequently faked his own suicide, which was later discovered. PMID:22721935

  14. Monitoring of gas and seismic energy release: new results from the multi-parametric benthic observatory SN-4 at MARsite location (Gulf of Izmit, Turkey)

    NASA Astrophysics Data System (ADS)

    Embriaco, Davide; Marinaro, Giuditta; Frugoni, Francesco; Monna, Stephen; Etiope, Giuseppe; Gasperini, Luca; Polonia, Alina; Del Bianco, Fabrizio; Namık Çaǧatay, M.; Ulgen, Umut B.; Favali, Paolo

    2014-05-01

    Episodic gas seepage occurs at the seafloor in the Gulf of Izmit (Sea of Marmara, NW Turkey) along the submerged segment of the North Anatolian Fault (NAF), which ruptured during the 1999 Mw7.4 Izmit earthquake, and caused tectonic loading of the fault segment in front of the Istanbul metropolitan area. Marmara site was selected as one EMSO (European Multidisciplinary Seafloor and water column Observatory) node where establish a permanent sea-bottom observatory. An autonomous and long-term multiparametric benthic observatory (SN-4) was deployed in order to study gas seepage and seismic energy release along the NAF. SN-4 operated in the gulf at the western end of the 1999 Izmit earthquake rupture for about one-year at 166 m water depth. The SN-4 payload included a three-component broad-band seismometer, as well as gas and oceanographic sensors. We analysed data collected continuously for 161 days in the first part of the experiment, from October 2009 to March 2010. The main objective of our work was to verify whether tectonic deformation along the NAF could trigger methane seepage. Results from the SN-4 experiment in the Sea of Marmara suggest that neither low-magnitude local seismicity, nor regional events affect intensity and frequency of gas flows from the seafloor. The SN-4 observatory was recently re-deployed in the same site for another one year mission (September 2013) in the framework of MARsite (New Directions in Seismic Hazard assessment through Focused Earth Observation in the Marmara Supersite) EC project which aims assessing the 'state of the art' of seismic risk evaluation and management at European level by long-term monitoring activities in Marmara Sea. References EMSO web site: http://www.emso-eu.org MARsite web site: http://www.marsite.eu/

  15. Are pre-hospital deaths from accidental injury preventable?

    PubMed Central

    Hussain, L. M.; Redmond, A. D.

    1994-01-01

    OBJECTIVE--To determine what proportion of pre-hospital deaths from accidental injury--deaths at the scene of the accident and those that occur before the person has reached hospital--are preventable. DESIGN--Retrospective study of all deaths from accidental injury that occurred between 1 January 1987 and 31 December 1990 and were reported to the coroner. SETTING--North Staffordshire. MAIN OUTCOME MEASURES--Injury severity score, probability of survival (probit analysis), and airway obstruction. RESULTS--There were 152 pre-hospital deaths from accidental injury (110 males and 42 females). In the same period there were 257 deaths in hospital from accidental injury (136 males and 121 females). The average age at death was 41.9 years for those who died before reaching hospital, and their average injury severity score was 29.3. In contrast, those who died in hospital were older and equally likely to be males or females. Important neurological injury occurred in 113 pre-hospital deaths, and evidence of airway obstruction in 59. Eighty six pre-hospital deaths were due to road traffic accidents, and 37 of these were occupants in cars. On the basis of the injury severity score and age, death was found to have been inevitable or highly likely in 92 cases. In the remaining 60 cases death had not been inevitable and airway obstruction was present in up to 51 patients with injuries that they might have survived. CONCLUSION--Death was potentially preventable in at least 39% of those who died from accidental injury before they reached hospital. Training in first aid should be available more widely, and particularly to motorists as many pre-hospital deaths that could be prevented are due to road accidents. PMID:8173428

  16. Fission gas release behaviour of a 103 GWd/tHM fuel disc during a 1200 °C annealing test

    NASA Astrophysics Data System (ADS)

    Noirot, J.; Pontillon, Y.; Yagnik, S.; Turnbull, J. A.; Tverberg, T.

    2014-03-01

    Within the Nuclear Fuel Industry Research (NFIR) program, several fuel variants, in the form of thin circular discs, were irradiated in the Halden Boiling Water Reactor (HBWR) to a range of burn-ups ˜100 GWd/tHM. The design of the assembly was similar to that used in other HBWR programs: the assembly contained several rods with fuel discs sandwiched between Mo discs, which limited temperature gradients within the fuel discs. One such rod contained standard grain UO2 discs (3D grain size = 18 μm) reaching a burn-up of 103 GWd/tHM. After the irradiation, the gas release upon rod puncturing was measured to be 2.9%.

  17. Gas release in the process of thermal treatment of sputtered Pb(Ti0.48Zr0.52)O x films

    NASA Astrophysics Data System (ADS)

    Znamenskii, A. G.; Ionov, A. M.; Marchenko, V. A.

    2016-06-01

    The conditions (regimes of deposition and thermal treatment) for gas bubble formation in ferroelectric Pb(Ti1- y Zr y )O3 films have been determined by thermal desorption and electron and optical micros-copy. A mechanism of bubble formation has been proposed. This mechanism rests upon the notion that lead can form oxides of the PbO2 type with a high oxygen content at relatively low temperatures and that these oxides break down with the release of oxygen to lower oxides of the PbO type upon subsequent heating. These ideas have been taken as the basis of a technique for the fabrication of Pb(Ti1- y Zr y )O3 films with a reduced (by an order of magnitude) density of through defects.

  18. Cattle and the oil and gas industry in Alberta: A literature review with recommendations for environmental management

    SciTech Connect

    1996-12-31

    The purpose of this report is to bring together a review of published information on the potential effects of upstream oil and gas industry operations on the cattle industry in Alberta, some indication of the probability of occurrence of these effects, and recommendations on how they might be avoided or mitigated. Based on reviews of scientific papers and industry good-practice manuals, the report describes: The sources and quantities of environmental contaminants generated by Alberta`s oil and gas industry, including normal operations, accidental releases, and the effects of aging infrastructure; the chemical composition of the products, materials, and wastes associated with the industry; the fate and transport of the contaminants through air, water, and soil; cattle operations in Alberta; the toxicology of oil and gas industry contaminants in cattle; and selected Alberta case studies of accidental releases and planned experiments. Conclusions and recommendations deal with critical information gaps and strategies for the sustainable management of cattle and oil/gas operations in the province.

  19. Accidental Nuclear War: The Growing Peril. Part I [and] Part II.

    ERIC Educational Resources Information Center

    Newcombe, Alan, Ed.

    1984-01-01

    Two volumes designed to increase awareness of accidental nuclear war dangers are presented. The first of 5 sections in volume I proposes that although accidental war is preventable, the current arms race and secrecy about accidents and false alarms increase the possibility of an accidental war. Section 2 posits that decreased decision-making time…

  20. Estimating trace gas and aerosol emissions over South America: Relationship between fire radiative energy released and aerosol optical depth observations

    NASA Astrophysics Data System (ADS)

    Pereira, Gabriel; Freitas, Saulo R.; Moraes, Elisabete Caria; Ferreira, Nelson Jesus; Shimabukuro, Yosio Edemir; Rao, Vadlamudi Brahmananda; Longo, Karla M.

    2009-12-01

    Contemporary human activities such as tropical deforestation, land clearing for agriculture, pest control and grassland management lead to biomass burning, which in turn leads to land-cover changes. However, biomass burning emissions are not correctly measured and the methods to assess these emissions form a part of current research area. The traditional methods for estimating aerosols and trace gases released into the atmosphere generally use emission factors associated with fuel loading and moisture characteristics and other parameters that are hard to estimate in near real-time applications. In this paper, fire radiative power (FRP) products were extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) and from the Geostationary Operational Environmental Satellites (GOES) fire products and new South America generic biomes FRE-based smoke aerosol emission coefficients were derived and applied in 2002 South America fire season. The inventory estimated by MODIS and GOES FRP measurements were included in Coupled Aerosol-Tracer Transport model coupled to the Brazilian developments on the Regional Atmospheric Modeling System (CATT-BRAMS) and evaluated with ground truth collected in Large Scale Biosphere-Atmosphere Smoke, Aerosols, Clouds, rainfall, and Climate (SMOCC) and Radiation, Cloud, and Climate Interactions (RaCCI). Although the linear regression showed that GOES FRP overestimates MODIS FRP observations, the use of a common external parameter such as MODIS aerosol optical depth product could minimize the difference between sensors. The relationship between the PM 2.5μm (Particulate Matter with diameter less than 2.5 μm) and CO (Carbon Monoxide) model shows a good agreement with SMOCC/RaCCI data in the general pattern of temporal evolution. The results showed high correlations, with values between 0.80 and 0.95 (significant at 0.5 level by student t test), for the CATT-BRAMS simulations with PM 2.5μm and CO.

  1. The Bubble Box: Towards an Automated Visual Sensor for 3D Analysis and Characterization of Marine Gas Release Sites.

    PubMed

    Jordt, Anne; Zelenka, Claudius; von Deimling, Jens Schneider; Koch, Reinhard; Köser, Kevin

    2015-01-01

    Several acoustic and optical techniques have been used for characterizing natural and anthropogenic gas leaks (carbon dioxide, methane) from the ocean floor. Here, single-camera based methods for bubble stream observation have become an important tool, as they help estimating flux and bubble sizes under certain assumptions. However, they record only a projection of a bubble into the camera and therefore cannot capture the full 3D shape, which is particularly important for larger, non-spherical bubbles. The unknown distance of the bubble to the camera (making it appear larger or smaller than expected) as well as refraction at the camera interface introduce extra uncertainties. In this article, we introduce our wide baseline stereo-camera deep-sea sensor bubble box that overcomes these limitations, as it observes bubbles from two orthogonal directions using calibrated cameras. Besides the setup and the hardware of the system, we discuss appropriate calibration and the different automated processing steps deblurring, detection, tracking, and 3D fitting that are crucial to arrive at a 3D ellipsoidal shape and rise speed of each bubble. The obtained values for single bubbles can be aggregated into statistical bubble size distributions or fluxes for extrapolation based on diffusion and dissolution models and large scale acoustic surveys. We demonstrate and evaluate the wide baseline stereo measurement model using a controlled test setup with ground truth information. PMID:26690168

  2. The Bubble Box: Towards an Automated Visual Sensor for 3D Analysis and Characterization of Marine Gas Release Sites

    PubMed Central

    Jordt, Anne; Zelenka, Claudius; Schneider von Deimling, Jens; Koch, Reinhard; Köser, Kevin

    2015-01-01

    Several acoustic and optical techniques have been used for characterizing natural and anthropogenic gas leaks (carbon dioxide, methane) from the ocean floor. Here, single-camera based methods for bubble stream observation have become an important tool, as they help estimating flux and bubble sizes under certain assumptions. However, they record only a projection of a bubble into the camera and therefore cannot capture the full 3D shape, which is particularly important for larger, non-spherical bubbles. The unknown distance of the bubble to the camera (making it appear larger or smaller than expected) as well as refraction at the camera interface introduce extra uncertainties. In this article, we introduce our wide baseline stereo-camera deep-sea sensor bubble box that overcomes these limitations, as it observes bubbles from two orthogonal directions using calibrated cameras. Besides the setup and the hardware of the system, we discuss appropriate calibration and the different automated processing steps deblurring, detection, tracking, and 3D fitting that are crucial to arrive at a 3D ellipsoidal shape and rise speed of each bubble. The obtained values for single bubbles can be aggregated into statistical bubble size distributions or fluxes for extrapolation based on diffusion and dissolution models and large scale acoustic surveys. We demonstrate and evaluate the wide baseline stereo measurement model using a controlled test setup with ground truth information. PMID:26690168

  3. Greenhouse gas emissions and reactive nitrogen releases during the life-cycles of staple food production in China and their mitigation potential.

    PubMed

    Xia, Longlong; Ti, Chaopu; Li, Bolun; Xia, Yongqiu; Yan, Xiaoyuan

    2016-06-15

    Life-cycle analysis of staple food (rice, flour and corn-based fodder) production and assessments of the associated greenhouse gas (GHG) and reactive nitrogen (Nr) releases, from environmental and economic perspectives, help to develop effective mitigation options. However, such evaluations have rarely been executed in China. We evaluated the GHG and Nr releases per kilogram of staple food production (carbon and Nr footprints) and per unit of net economic benefit (CO2-NEB and Nr-NEB), and explored their mitigation potential. Carbon footprints of food production in China were obviously higher than those in some developed countries. There was a high spatial variation in the footprints, primarily attributable to differences in synthetic N use (or CH4 emissions) per unit of food production. Provincial carbon footprints had a significant linear relationship with Nr footprints, attributed to large contribution of N fertilizer use to both GHG and Nr releases. Synthetic N fertilizer applications and CH4 emissions dominated the carbon footprints, while NH3 volatilization and N leaching were the main contributors to the Nr footprints. About 564 (95% uncertainty range: 404-701) TgCO2eqGHG and 10 (7.4-12.4) Tg Nr-N were released every year during 2001-2010 from staple food production. This caused the total damage costs of 325 (70-555) billion ¥, equivalent to nearly 1.44% of the Gross Domestic Product of China. Moreover, the combined damage costs and economic input costs, accounted for 66%-80% of the gross economic benefit generated from food production. A reduction of 92.7TgCO2eqyr(-1) and 2.2TgNr-Nyr(-1) could be achieved by reducing synthetic N inputs by 20%, increasing grain yields by 5% and implementing off-season application of straw and mid-season drainage practices for rice cultivation. In order to realize these scenarios, an ecological compensation scheme should be established to incentivize farmers to gradually adopt knowledge-based managements. PMID:26971213

  4. Selection of Hydrological Model for Waterborne Release

    SciTech Connect

    Blanchard, A.

    1999-04-21

    Following a request from the States of South Carolina and Georgia, downstream radiological consequences from postulated accidental aqueous releases at the three Savannah River Site nonreactor nuclear facilities will be examined. This evaluation will aid in determining the potential impacts of liquid releases to downstream populations on the Savannah River. The purpose of this report is to evaluate the two available models and determine the appropriate model for use in following waterborne release analyses. Additionally, this report will document the accidents to be used in the future study.

  5. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers.

    PubMed

    Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

    2016-06-01

    Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O2 content and had emitted significantly more CO2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to

  6. Accidental Electric Shock during Pregnancy: Reflection on a Case

    PubMed Central

    Awwad, Johnny; Hannoun, Antoine; Fares, Farah; Ghazeeri, Ghina

    2013-01-01

    Objectives Data on fetal effects following accidental electric shock during pregnancy are scarce. We report on a case of accidental maternal electric shock associated with benign fetal arrhythmia in a woman at 28 weeks' gestation. Study Design Case report. Results Although electrocution involving low-voltage, low-frequency current has been associated with fatal cardiac arrhythmias and conduction abnormalities, two protective parameters in the present case likely reduced the fetal injury: the dry skin at the site of current entry and the hand-to-hand pathway of current flow. Conclusion Because the pathophysiology of electric injury is altered during pregnancy, assessment of fetal well-being should be prompted no matter how trivial an incident may appear. PMID:24147245

  7. Accidental intraoral injection of formalin during extraction: case report.

    PubMed

    Swami, Pushp Chander; Raval, Rushik; Kaur, Mandeep; Kaur, Jasleen

    2016-04-01

    Transparent, clear solutions such as hydrogen peroxide, alcohol, sodium hypochlorite, formaldehyde, and local anaesthetics are widely used in dentistry, so the tissues are liable to accidental injury. Formalin, a 37%-40% solution of formaldehyde, is extensively used in 10% solution as a tissue preservative, but it has toxic effects on systems such as the gastrointestinal tract, respiratory tract, skin, and mucosa. However, we know of few reports of cases of inadvertent injection of alcohol and formalin directly into the human body. In this case report we describe the early and delayed clinical effects of accidental intraoral injection of formalin, the subsequent symptoms and management, and some prudent points that should be learnt to avoid such incidents in the future. PMID:26794082

  8. Accidental degeneracy of double Dirac cones in a phononic crystal

    PubMed Central

    Chen, Ze-Guo; Ni, Xu; Wu, Ying; He, Cheng; Sun, Xiao-Chen; Zheng, Li-Yang; Lu, Ming-Hui; Chen, Yan-Feng

    2014-01-01

    Artificial honeycomb lattices with Dirac cone dispersion provide a macroscopic platform to study the massless Dirac quasiparticles and their novel geometric phases. In this paper, a quadruple-degenerate state is achieved at the center of the Brillouin zone in a two-dimensional honeycomb lattice phononic crystal, which is a result of accidental degeneracy of two double-degenerate states. In the vicinity of the quadruple-degenerate state, the dispersion relation is linear. Such quadruple degeneracy is analyzed by rigorous representation theory of groups. Using method, a reduced Hamiltonian is obtained to describe the linear Dirac dispersion relations of this quadruple-degenerate state, which is well consistent with the simulation results. Near such accidental degeneracy, we observe some unique properties in wave propagating, such as defect-insensitive propagating character and the Talbot effect. PMID:24714512

  9. Accidental ligature strangulation by an ironing machine: an unusual case.

    PubMed

    Dogan, Kamil Hakan; Demirci, Serafettin; Gunaydin, Gursel; Buken, Bora

    2010-01-01

    In this paper, we present a case of a 53-year-old woman who had her headscarf catch on the cylinder ironing machine in the laundry of the hospital where she worked. The hospital workers found the woman dead with her head stuck to the ironing machine. After the death scene investigation and autopsy were completed, it was determined that the death occurred as a result of accidental ligature strangulation. Accidental ligature strangulation in which an article of clothing is caught in such an electrical machine and strangles the wearer is very rare. This case highlights the fact that these kinds of machines can be hazardous to work around and that increased safety measures should be taken to insure worker safety; additionally, the people who use these machines should be educated on the potential hazards. PMID:20002258

  10. Food allergy: practical approach on education and accidental exposure prevention.

    PubMed

    Pádua, I; Moreira, A; Moreira, P; Barros, R

    2016-09-01

    Food allergies are a growing problem and currently the primary treatment of food allergy is avoidance of culprit foods. However, given the lack of information and education and also the ubiquitous nature of allergens, accidental exposures to food allergens are not uncommon. The fear of potential fatal reactions and the need of a proper avoidance leads in most of the cases to the limitation of leisure and social activities. This review aims to be a practical approach on education and accidental exposure prevention regarding activities like shopping, eating out, and travelling. The recommendations are focused especially on proper reading of food labels and the management of the disease, namely in restaurants and airplanes, concerning cross-contact and communication with other stakeholders. The implementation of effective tools is essential to manage food allergy outside home, avoid serious allergic reactions and minimize the disease's impact on individuals' quality of life. PMID:27608473

  11. Parental substance abuse and accidental death in children.

    PubMed

    Palmiere, Cristian; Staub, Christian; La Harpe, Romano; Mangin, Patrice

    2010-05-01

    In this report, the authors present two cases of accidental death in children of addicted parents. In the first case, the child was left unattended at home while the mother went out to buy cocaine. She was arrested and detained with no mention of the unsupervised child. The cause of death in this case was determined to be starvation and dehydration. In the second case, a child mistakenly received a methadone suppository by her father instead of an antipyretic suppository. Toxicological analysis of the femoral blood revealed methadone at a concentration of 1.2 mg/L. The cause of death was determined to be methadone intoxication. The literature is reviewed and discussed. We report these cases to illustrate the risk of harm to children from illicit drugs and prescription medications at home and because there is no mention of accidental death in children following a methadone suppository administration in the current literature. PMID:20345788

  12. [Sustained-release dextropropoxyphene.].

    PubMed

    Kurz-Müller, K; Zenz, M

    1991-12-01

    Dextropropoxyphene is a mild opioid analgesic whose analgesic potency corresponds to that of acetylsalicylic acid and paracetamol. It has a similar analgesic effect to codeine but also a considerably lower addiction and dependence potential. Dextropropoxyphene is a therapeutic alternative to other weak opioids such as codeine or dihydrocodeine. In the case of absolute intolerance of non-steroidal anti-inflammatory agents, their analgesic effect can be replaced by that of dextropropoxyphene. In case of relative intolerance, i.e. occurrence of non-tolerable side-effects, the dose of non-steroidal anti-inflammatory agents can be kept low by additional administration of dextropropoxyphene, which simultaneously enhances analgesia. Analgesics are prescribed according to a definite time schedule for the long-term treatment of chronic pain. The oral route of administration is preferred since it enables the patient to be independent of the nursing staff. Sustained-release drugs with a duration of action of at least 8 h are used in preference to other preparations. Sustained-release dextropropoxyphene provides analgesia for 8-12 h. Sustained-release dextropropoxyphene clearly differs from non-sustained-release dextropropoxyphene in its pharmacokinetics. Repeated administration of the sustained-release form at the therapeutically recommended intervals does not lead to cumulation, and the risk of accidental overdosage is extremely low. Intoxication can only occur after simultaneous ingestion of alcohol or other centrally depressant substances or in the presence of hepatic and/or renal failure. Sustained-release dextropropoxyphene is a sensible and undeniable alternative for the second stage in the analgesic ladder of chronic pain therapy. PMID:18415177

  13. Paediatric femur fractures at the emergency department: accidental or not?

    PubMed

    Hoytema van Konijnenburg, Eva M M; Vrolijk-Bosschaart, Thekla F; Bakx, Roel; Van Rijn, Rick R

    2016-01-01

    Only a small proportion of all paediatric fractures is caused by child abuse or neglect, especially in highly prevalent long bone fractures. It can be difficult to differentiate abusive fractures from non-abusive fractures. This article focuses on femoral fractures in young children. Based on three cases, this article presents a forensic evidence-based approach to differentiate between accidental and non-accidental causes of femoral fractures. We describe three cases of young children who were presented to the emergency department because of a suspected femur fracture. Although in all cases, the fracture had a similar location and appearance, the clinical history and developmental stage of the child led to three different conclusions. In the first two cases, an accidental mechanism was a plausible conclusion, although in the second case, neglect of parental supervision was the cause for concern. In the third case, a non-accidental injury was diagnosed and appropriate legal prosecution followed. Any doctor treating children should always be aware of the possibility of child abuse and neglect in children with injuries, especially in young and non-mobile children presenting with an unknown trauma mechanism. If a suspicion of child abuse or neglect arises, a thorough diagnostic work-up should be performed, including a full skeletal survey according to the guidelines of the Royal College of Radiologists and the Royal College of Paediatrics and Child Health. In order to make a good assessment, the radiologist reviewing the skeletal survey needs access to all relevant clinical and social information. PMID:26642309

  14. A case of accidental ingestion of ant bait containing fipronil.

    PubMed

    Fung, Hin Tat; Chan, Kar Ki; Ching, Wei Ming; Kam, Chak Wah

    2003-01-01

    A 77-year-old woman accidentally ingested a commercial ant bait containing fipronil without development of obvious toxicity, supporting the safety of this new insecticide as demonstrated in animal studies. However, concentrated agricultural products may be more toxic, and the potential for seizures should not be overlooked. The pharmacological action, mechanism of selective insect toxicity, and clinical effects of fipronil are discussed. PMID:12807306

  15. An investigation of accidental ingestion during dental procedures.

    PubMed

    Obinata, Kenichi; Satoh, Takafumi; Towfik, Alam Mohammad; Nakamura, Motoyasu

    2011-12-01

    Twenty-three cases of accidental ingestion during dental procedures, which occurred at the Center for Dental Clinics of Hokkaido University Hospital between 2006 and 2010, were analyzed retrospectively. We examined not only the objects ingested, but also details of the circumstances (treated teeth, types of treatment, professional experience of the practitioners). Except for two cases (an unidentified endodontic file and the tip of an ultrasonic scaler, which were recovered by vacuuming), the other 21 accidentally ingested objects were all found in the digestive tract, and none in the respiratory tract, by radiographic examination of the chest and abdomen. The ingested objects were mostly metal restorations (inlays or onlays) or prostheses (crowns or cores). Ingestion occurred more frequently during treatment of lower molars, and when procedures were being conducted by practitioners with less than 5 years of experience. No adverse events related to ingestion were reported. The present study found no cases of aspiration or complications related to the ingested objects. However, considering the risk of life-threatening emergencies related to accidental aspiration and ingestion, dentists must take meticulous precautions and be ready to deal with this kind of emergency during dental procedures. PMID:22167036

  16. Prevention of accidental exposure in radiotherapy: the risk matrix approach.

    PubMed

    Vilaragut, J J; Duménigo, C; Delgado, J M; Morales, J; McDonnell, J D; Ferro, R; Ortiz López, P; Ramírez, M L; Pérez Mulas, A; Papadopulos, S; Gonçalves, M; López Morones, R; Sánchez Cayuela, C; Cascajo Castresana, A; Somoano, F; Álvarez, C; Guillén, A; Rodríguez, M; Pereira, P P; Nader, A

    2013-02-01

    Knowledge and lessons from past accidental exposures in radiotherapy are very helpful in finding safety provisions to prevent recurrence. Disseminating lessons is necessary but not sufficient. There may be additional latent risks for other accidental exposures, which have not been reported or have not occurred, but are possible and may occur in the future if not identified, analyzed, and prevented by safety provisions. Proactive methods are available for anticipating and quantifying risk from potential event sequences. In this work, proactive methods, successfully used in industry, have been adapted and used in radiotherapy. Risk matrix is a tool that can be used in individual hospitals to classify event sequences in levels of risk. As with any anticipative method, the risk matrix involves a systematic search for potential risks; that is, any situation that can cause an accidental exposure. The method contributes new insights: The application of the risk matrix approach has identified that another group of less catastrophic but still severe single-patient events may have a higher probability, resulting in higher risk. The use of the risk matrix approach for safety assessment in individual hospitals would provide an opportunity for self-evaluation and managing the safety measures that are most suitable to the hospital's own conditions. PMID:23274816

  17. Compact fluorescent lamp phosphors in accidental radiation monitoring.

    PubMed

    Murthy, K V R; Pallavi, S P; Ghildiyal, Rahul; Parmar, Manish C; Patel, Y S; Ravi Kumar, V; Sai Prasad, A S; Natarajan, V; Page, A G

    2006-01-01

    The application of lamp phosphors for accidental dosimetry is a new concept. Since the materials used in fluorescent lamps are good photo luminescent materials, if one can either use the inherent defects present in the phosphor or add suitable modifiers to induce thermoluminescence (TL) in these phosphors, then the device (fluorescent lamp) can be used as an accidental dosemeter. In continuation of our search for a suitable phosphor material, which can serve both as an efficient lamp phosphor and as a good radiation monitoring device, detailed examination has been carried out on cerium and terbium-doped lanthanum phosphate material. A (90)Sr beta source with 50 mCi strength (1.85 GBq) was used as the irradiation source for TL studies. The TL response as a function of dose received was examined for all phosphors used and it was observed that the intensity of the TL peak vs. dose received was a linear function in the dose range 0.1-200 Gy in each case. Incidentally LaPO(4): Ce,Tb is a component of the compact fluorescent lamp marketed recently as an energy bright light source. Besides having very good luminescence efficiency, good dosimetric properties of these phosphors render them useful for their use in accidental dosimetry also. PMID:16816401

  18. Accidental dural puncture rates in UK obstetric practice.

    PubMed

    Gleeson, C M; Reynolds, F

    1998-10-01

    Headache following epidural analgesia is a common cause of complaint, but accidental dural puncture rates vary among hospitals and with techniques. We were therefore interested to discover the extent of audit of dural puncture, the dural puncture rates in those UK centres that kept reliable records, and the techniques they used for detecting the epidural space. Consultants in charge of anaesthetic services to all 257 obstetric units in the UK were sent a questionnaire requesting numbers of obstetric epidurals, techniques used to detect the epidural space and the numbers of accidental dural punctures in the years 1991-1995. Replies were received from 191 respondents (74%) of whom 104 were able to provide some information about dural puncture rates. Dural puncture rate was inversely related to the number of epidurals performed; the highest recorded rate was 3.6% in a unit with < 300 epidurals annually, and the lowest 0.19% in a unit with > 1000. Most respondents did not record the loss of resistance technique used but among those who did, the dural puncture rate using mainly saline was 0.69% and using mainly air was 1.11% (P<0.001). Since accurate patient information is crucial for informed consent, audit needs to be improved in many centres. Though the accidental dural puncture rate may be under-reported in this survey, our data are in agreement with other findings that loss of resistance to saline is safer than loss of resistance to air. PMID:15321187

  19. An alternative approach for computing seismic response with accidental eccentricity

    NASA Astrophysics Data System (ADS)

    Fan, Xuanhua; Yin, Jiacong; Sun, Shuli; Chen, Pu

    2014-09-01

    Accidental eccentricity is a non-standard assumption for seismic design of tall buildings. Taking it into consideration requires reanalysis of seismic resistance, which requires either time consuming computation of natural vibration of eccentric structures or finding a static displacement solution by applying an approximated equivalent torsional moment for each eccentric case. This study proposes an alternative modal response spectrum analysis (MRSA) approach to calculate seismic responses with accidental eccentricity. The proposed approach, called the Rayleigh Ritz Projection-MRSA (RRP-MRSA), is developed based on MRSA and two strategies: (a) a RRP method to obtain a fast calculation of approximate modes of eccentric structures; and (b) an approach to assemble mass matrices of eccentric structures. The efficiency of RRP-MRSA is tested via engineering examples and compared with the standard MRSA (ST-MRSA) and one approximate method, i.e., the equivalent torsional moment hybrid MRSA (ETM-MRSA). Numerical results show that RRP-MRSA not only achieves almost the same precision as ST-MRSA, and is much better than ETM-MRSA, but is also more economical. Thus, RRP-MRSA can be in place of current accidental eccentricity computations in seismic design.

  20. Release mitigation spray safety systems for chemical demilitarization applications.

    SciTech Connect

    Leonard, Jonathan; Tezak, Matthew Stephen; Brockmann, John E.; Servantes, Brandon; Sanchez, Andres L.; Tucker, Mark David; Allen, Ashley N.; Wilson, Mollye C.; Lucero, Daniel A.; Betty, Rita G.

    2010-06-01

    Sandia National Laboratories has conducted proof-of-concept experiments demonstrating effective knockdown and neutralization of aerosolized CBW simulants using charged DF-200 decontaminant sprays. DF-200 is an aqueous decontaminant, developed by Sandia National Laboratories, and procured and fielded by the US Military. Of significance is the potential application of this fundamental technology to numerous applications including mitigation and neutralization of releases arising during chemical demilitarization operations. A release mitigation spray safety system will remove airborne contaminants from an accidental release during operations, to protect personnel and limit contamination. Sandia National Laboratories recently (November, 2008) secured funding from the US Army's Program Manager for Non-Stockpile Chemical Materials Agency (PMNSCMA) to investigate use of mitigation spray systems for chemical demilitarization applications. For non-stockpile processes, mitigation spray systems co-located with the current Explosive Destruction System (EDS) will provide security both as an operational protective measure and in the event of an accidental release. Additionally, 'tented' mitigation spray systems for native or foreign remediation and recovery operations will contain accidental releases arising from removal of underground, unstable CBW munitions. A mitigation spray system for highly controlled stockpile operations will provide defense from accidental spills or leaks during routine procedures.

  1. Detection of Mycobacterium tuberculosis in sputum by gas chromatography-mass spectrometry of methyl mycocerosates released by thermochemolysis.

    PubMed

    O'Sullivan, Denise M; Nicoara, Simona C; Mutetwa, Reggie; Mungofa, Stanley; Lee, Oona Y-C; Minnikin, David E; Bardwell, Max W; Corbett, Elizabeth L; McNerney, Ruth; Morgan, Geraint H

    2012-01-01

    Tuberculosis requires rapid diagnosis to prevent further transmission and allow prompt administration of treatment. Current methods for diagnosing pulmonary tuberculosis lack sensitivity are expensive or are extremely slow. The identification of lipids using gas chromatography- electron impact mass spectrometry (GC-EI/MS) could provide an alternative solution. We have studied mycocerosic acid components of the phthiocerol dimycocerosate (PDIM) family of lipids using thermochemolysis GC-EI/MS. To facilitate use of the technology in a routine diagnostic laboratory a simple extraction procedure was employed where PDIMs were extracted from sputum using petroleum ether, a solvent of low polarity. We also investigated a method using methanolic tetramethylammonium hydroxide, which facilitates direct transesterification of acidic components to methyl esters in the inlet of the GC-MS system. This eliminates conventional chemical manipulations allowing rapid and convenient analysis of samples. When applied to an initial set of 40 sputum samples, interpretable results were obtained for 35 samples with a sensitivity relative to culture of 94% (95%CI: 69.2,100) and a specificity of 100% (95%CI: 78.1,100). However, blinded testing of a larger set of 395 sputum samples found the assay to have a sensitivity of 61.3% (95%CI: 54.9,67.3) and a specificity of 70.6% (95%CI: 62.3,77.8) when compared to culture. Using the results obtained we developed an improved set of classification criteria, which when applied in a blinded re-analysis increased the sensitivity and specificity of the assay to 64.9% (95%CI: 58.6,70.8) and 76.2% (95%CI: 68.2,82.8) respectively. Highly variable levels of background signal were observed from individual sputum samples that inhibited interpretation of the data. The diagnostic potential of using thermochemolytic GC-EI/MS of PDIM biomarkers for diagnosis of tuberculosis in sputum has been established; however, further refinements in sample processing are

  2. Self-locking double retention redundant pull pin release

    NASA Technical Reports Server (NTRS)

    Killgrove, Thomas O. (Inventor)

    1987-01-01

    A double-retention redundant pull pin release system is disclosed. The system responds to a single pull during an intentional release operation. A spiral-threaded main pin is seated in a mating bore in a housing, which main pin has a flange fastened thereon at the part of the main pin which is exterior to the housing. Accidental release tends to rotate the main pin. A secondary pin passes through a slightly oversized opening in the flange and is seated in a second bore in the housing. The pins counteract against one another to prevent accidental release. A frictional lock is shared between the main and secondary pins to enhance further locking of the system. The secondary pin, in response to a first pull, is fully retracted from its bore and flange hole. Thereafter the pull causes the main pin to rotate free of the housing to release, for example, a parachute mechanism.

  3. A shallow water model for dense gas simulation in urban areas

    SciTech Connect

    Brown, Michael; Williams, Mike D; Gowardhan, Akshay; Brambilla, Sara; Manca, Davide

    2009-01-01

    Large quantities of toxic chemicals are stored at industrial facilities and transported around the country via train and truck. In the event of an accidental release, many of these chemicals are released as heavier-than-air gases that stay low to the ground as they are transported by the wind . Breathing height concentrations can remain high due to reduced vertical mixing and hazard zone coverage area can be larger due to near-source gravitational slumping . A number of fast-response dense gas dispersion models have been developed and are routinely used to deal with heavier-than-air releases over unobstructed terrain. If a release were to occur in a built-up environment, however, the effects of buildings and other obstacles will significantly alter the initial spreading, the transport direction, and the amount of mixing of the dense gas cloud . We have developed a new fast-running dense gas dispersion model that is intended for handling releases in cities and at large industrial facilities. In this paper we describe the scheme employed and how the model has been integrated into the Quick Urban & Industrial Complex (QUIC) dispersion modeling system.

  4. Environmental release of chemicals and reproductive ecology.

    PubMed

    Bajaj, J S; Misra, A; Rajalakshmi, M; Madan, R

    1993-07-01

    Reproductive ecology is defined as "the study of causes and mechanisms of the effects of environmental risk factors on reproductive health and the methods of their prevention and management." Major areas of concern, within the purview of this paper, relate to adverse pregnancy outcomes, effects on target tissues in the male and the female, and alterations in the control and regulatory mechanisms of reproductive processes. Teratogenic potential of chemicals, released as a result of accidents and catastrophes, is of critical significance. Congenital Minamata disease is due to transplacental fetal toxicity caused by accidental ingestion of methyl mercury. Generalized disorders of ectodermal tissue following prenatal exposure to polychlorinated biphenyls have been reported in Taiwan and Japan. The Bhopal gas disaster, a catastrophic industrial accident, was due to a leak of toxic gas, methyl isocyanate (MIC), in the pesticide manufacturing process. The outcome of pregnancy was studied in female survivors of MIC exposure. The spontaneous abortion rate was nearly four times more common in the affected areas as compared to the control area (24.2% versus 5.6%; p < 0.0001). Furthermore, while stillbirth rate was found to be similar in the affected and control areas, the perinatal and neonatal mortality rates were observed to be higher in the affected area. The rate of congenital malformations in the affected and control areas did not show any significant difference. Chromosomal aberrations and sister chromatid exchange (SCE) frequencies were investigated in human survivors of exposure. The observed SCE frequencies in control and exposed groups indicated that mutagenesis has been induced. Strategies for the management, prediction, and preventability of such disasters are outlined. PMID:8243381

  5. Sensor Networks for Detecting Toxic Releases in Buildings

    SciTech Connect

    Sohn, MIchael D.; Gadgil, Ashok J.; Sreedharan, Priya; Nazaroff, William W.

    2009-03-01

    Sudden releases of a toxic agent indoors can cause immediate and long-term harm to occupants. In order to protect building occupants from such threats, it is necessary to have a robust air monitoring system that can detect, locate, and characterize accidental or deliberate toxic gas releases. However, developing such a system is complicated by several requirements, in particular the need to operate in real-time. This task is further complicated when monitoring sensors are prone to false positive and false negative readings. We report on work towards developing an indoor monitoring system that is robust even in the presence of poor quality sensor data. The algorithm, named BASSET, combines deterministic modeling and Bayesian statistics to join prior knowledge of the contaminant transport in the building with real-time sensor information. We evaluate BASSET across several data sets, which vary in sensor characteristics such as accuracy, response time, and trigger level. Our results suggest that optimal designs are not always intuitive. For example, a network comprised of slower but more accurate sensors may locate the contaminant source more quickly than a network with faster but less accurate sensors.

  6. Preventative safety management supported by an emergency response system for sour gas production in North Germany

    SciTech Connect

    Grossmann, U.M.; Schoenbach, H.C.

    1996-12-31

    In general, the onshore production of oil and gas in North place in densely populated areas. Approximately 800 MMSCFD of gas are produced from sour gas reservoirs, with H{sub 2}S-concentrations of up to 20 Vol.-% being involved. Despite a high technical safety standard and different organizational measures in the production of sour gas, emergency cases cannot be absolutely ruled out. H{sub 2}S concentrations of more than 700 ppm will cause immediate death. In Germany the production of hydrocarbons is regulated by the Federal Mining Law. According to these regulations an extensive gas protection plan and gas alarm plan have to be set up for sour gas operations. This includes establishing an emergency response organization and a gas alarm management guide. Beyond the legal requirements Mobil Erdgas-Erdoel GmbH (MEEG) has implemented an emergency response management system in compliance with Mobil Oil`s worldwide safety philosophy to minimize the risk for the population, the employees and the environment. The installation of two electronic data systems enables the crisis management team to respond faster, more safely and in a less complicated manner to accidental sour gas releases. The introduction of the Emergency Information and Response System (EMIS) makes possible the display and manipulation of maps in different scales and geographically oriented data. The expansion of the process master computer by installing an H{sub 2}S-Gas alarm system has achieved the online measurements of H{sub 2}S concentrations, wind direction and wind velocity at sour gas production facilities. The system, which is operated at the gas dispatcher center, gives the crisis response team the opportunity to predict the location of sour gas release and the area being impacted. Consequently rescue parties will be directed to the location in a safe manner and, if necessary, measures will be managed for evacuating the residents living in the danger zones around sour gas facilities.

  7. An atmospheric tritium release database for model comparisons

    SciTech Connect

    Murphy, C.E. Jr.; Wortham, G.R.

    1991-12-19

    A database of vegetation, soil, and air tritium concentrations at gridded coordinate locations following nine accidental atmospheric releases is described. While none of the releases caused a significant dose to the public, the data collected is valuable for comparison with the results of tritium transport models used for risk assessment. The largest, potential, individual off-site dose from any of the releases was calculated to be 1.6 mrem. The population dose from this same release was 46 person-rem which represents 0.04% of the natural background radiation dose to the population in the path of the release.

  8. An atmospheric tritium release database for model comparisons. Revision 1

    SciTech Connect

    Murphy, C.E. Jr.; Wortham, G.R.

    1995-01-01

    A database of vegetation, soil, and air tritium concentrations at gridded coordinate locations following nine accidental atmospheric releases is described. While none of the releases caused a significant dose to the public, the data collected are valuable for comparison with the results of tritium transport models used for risk assessment. The largest, potential, individual off-site dose from any of the releases was calculated to be 1.6 mrem. The population dose from this same release was 46 person-rem which represents 0.04% of the natural background radiation dose to the population in the path of the release.

  9. Development of emergency response tools for accidental radiological contamination of French coastal areas.

    PubMed

    Duffa, Céline; Bailly du Bois, Pascal; Caillaud, Matthieu; Charmasson, Sabine; Couvez, Céline; Didier, Damien; Dumas, Franck; Fievet, Bruno; Morillon, Mehdi; Renaud, Philippe; Thébault, Hervé

    2016-01-01

    The Fukushima nuclear accident resulted in the largest ever accidental release of artificial radionuclides in coastal waters. This accident has shown the importance of marine assessment capabilities for emergency response and the need to develop tools for adequately predicting the evolution and potential impact of radioactive releases to the marine environment. The French Institute for Radiological Protection and Nuclear Safety (IRSN) equips its emergency response centre with operational tools to assist experts and decision makers in the event of accidental atmospheric releases and contamination of the terrestrial environment. The on-going project aims to develop tools for the management of marine contamination events in French coastal areas. This should allow us to evaluate and anticipate post-accident conditions, including potential contamination sites, contamination levels and potential consequences. In order to achieve this goal, two complementary tools are developed: site-specific marine data sheets and a dedicated simulation tool (STERNE, Simulation du Transport et du transfert d'Eléments Radioactifs dans l'environNEment marin). Marine data sheets are used to summarize the marine environment characteristics of the various sites considered, and to identify vulnerable areas requiring implementation of population protection measures, such as aquaculture areas, beaches or industrial water intakes, as well as areas of major ecological interest. Local climatological data (dominant sea currents as a function of meteorological or tidal conditions) serving as the basis for an initial environmental sampling strategy is provided whenever possible, along with a list of possible local contacts for operational management purposes. The STERNE simulation tool is designed to predict radionuclide dispersion and contamination in seawater and marine species by incorporating spatio-temporal data. 3D hydrodynamic forecasts are used as input data. Direct discharge points or

  10. Human health effects from accidental release of tetrachlorodibenzo-p-dioxin (TCDD) at Seveso, Italy.

    PubMed

    Pocchiari, F; Silano, V; Zampieri, A

    1979-05-31

    This paper is a progress report of the epidemiologic work carried out under the supervision of the Lombardy Regional Authority during the two years elapsed from the accident in a TCP-producing factory (ICMESA) in Meda (Italy), which resulted in the contamination of several towns of a large, densely populated area called the Brianza di Seveso with a total population of 220,000 inhabitants. A wide follow-up program is in progress in the Seveso area; it includes a clinical screening of the population living in the contaminated area and longitudinal and systematic health control of different groups at risk; a long-term morbidity cohort study has been also undertaken. TCDD exposure following the ICMESA accident resulted in an increased chloracne frequency. Neurologic examinations showed both signs of idiopathic subclinical neurologic damage and cases of clinically detectable idiopathic polyneuropathy in adults. A limited percentage of idiopathic hepatomegaly was reported to be present on clinical investigation; no information, however, is given on the criteria by which the hepatomegaly was investigated. Some alterations were observed in some exposed people in one or more liver tests (mainly transaminases and gamma-GT). So far, immunologic investigations, cytogenetic examination and embryomorphology analysis on cases of therapeutical or spontaneous abortions have not given abnormal results. PMID:287395

  11. (Agricultural countermeasures following an accidental release of radionuclides): Foreign trip report, June 11--22, 1989

    SciTech Connect

    Auerbach, S.I.

    1989-07-05

    This report describes foreign travel of S. I. Auerbach of the Environmental Sciences Division (ESD), Oak Ridge National Laboratory (ORNL), who attended workshops dealing with radioecological protection studies of the northeast Atlantic and with agricultural countermeasures following a nuclear accident. These workshops were sponsored by the Commission of the European Community (CEC) and the International Union of Radioecologists (IUR). As past president of the IUR and member of its Executive Committee, the traveler also participated in the annual meeting of that organization. The workshop on marine radioecology heard the reports of four marine research groups: (1) studies of nuclear effluent discharges into North European waters; (2) studies of transport and fate of radionuclides; (3) radioactivity of marine produce; and (4) collective dose assessment. These investigations are being carried out by large research groups in the United Kingdom, Denmark, West Germany, Ireland, Sweden, Holland, Belgium, and France. The reports were informative from both the radioprotection and radioecological research viewpoints.

  12. 78 FR 6149 - Final Interim Staff Guidance Assessing the Radiological Consequences of Accidental Releases of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-29

    ... contained in NUREG-0800, SRP dated March 2007. The NRC staff intends to incorporate these final ISGs into the next revision of RG 1.206 and NUREG-0800. On February 24, 2010 (75 FR 8411 and 75 FR 8412), the... supplements NUREG-0800 Standard Review Plan (SRP) Section 11.2 and Branch Technical Position 11-6 and...

  13. [Theoretic evaluation of allowable time for evacuation from occupational zone of accidentally released uranium hexafluoride].

    PubMed

    Babenko, S P

    2005-01-01

    Transdermal intake of uranium hexafluoride hydrolysis products is analysed. The authors present calculations of uranium and fluor amounts entering human body, in accordance with duration of stay in hazardous circumstances. PMID:16381480

  14. 78 FR 66321 - Approval of North Dakota Request for Partial Delegation of Prevention of Accidental Release...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... initials FR mean Federal Register. (vii) The initials CAS mean Chemical Abstract Service. (viii) The.... 61 FR 31668. These regulations require owners and operators of stationary sources subject to the.... Background A. Risk Management Program Background On January 31, 1994 (59 FR 4493), EPA promulgated...

  15. Accumulation of plutonium in mammalian wildlife tissues following dispersal by accidental-release tests.

    PubMed

    Johansen, M P; Child, D P; Caffrey, E A; Davis, E; Harrison, J J; Hotchkis, M A C; Payne, T E; Ikeda-Ohno, A; Thiruvoth, S; Twining, J R; Beresford, N A

    2016-01-01

    We examined the distribution of plutonium (Pu) in the tissues of mammalian wildlife inhabiting the relatively undisturbed, semi-arid former Taranaki weapons test site, Maralinga, Australia. The accumulation of absorbed Pu was highest in the skeleton (83% ± 6%), followed by muscle (10% ± 9%), liver (6% ± 6%), kidneys (0.6% ± 0.4%), and blood (0.2%). Pu activity concentrations in lung tissues were elevated relative to the body average. Foetal transfer was higher in the wildlife data than in previous laboratory studies. The amount of Pu in the gastrointestinal tract was highly elevated relative to that absorbed within the body, potentially increasing transfer of Pu to wildlife and human consumers that may ingest gastrointestinal tract organs. The Pu distribution in the Maralinga mammalian wildlife generally aligns with previous studies related to environmental exposure (e.g. Pu in humans from worldwide fallout), but contrasts with the partitioning models that have traditionally been used for human worker-protection purposes (approximately equal deposition in bone and liver) which appear to under-predict the skeletal accumulation in environmental exposure conditions. PMID:25910926

  16. Relocation Impacts of a Major Release from SRTC

    SciTech Connect

    Blanchard, A.

    1999-05-17

    The relocation impacts of an accidental release, scenario 1-RD-3 , are evaluated for the Savannah River Technology Center. The extent of the area potentially contaminated to a level that would result in doses exceeding the relocation protective action guide is calculated.

  17. Improving the U.S. EPA Toxic Release Inventory database for environmental health research.

    PubMed

    Neumann, C M

    1998-01-01

    In 1986, Congress passed the Emergency Planning and Community Right-to-Know Act (EPCRA) in response to the tragic death of thousands of people in Bhopal, India, following the accidental release of the toxic gas methyl isocyanate (MIC) from a Union Carbide facility. As a component of EPCRA, certain manufacturers are required to report annually the total mass (pounds per year, lb/yr) of toxic chemicals released into the environment (air, water, land, or underground injection), treated on-site, or shipped off-site for further waste treatment. This information is compiled by the U.S. Environmental Protection Agency (EPA) into a publicly accessible database known as the Toxic Release Inventory (TRI). The TRI database is designed to encourage pollution prevention and waste reduction by increasing public access to and knowledge of environmental chemical releases. EPCRA has been generally considered by industry, government, and community representatives as one of the most successful environmental laws in U.S. history. Over the past few years, EPA has initiated a three-phased expansion to EPCRA reporting requirements that will enhance the overall usefulness of the TRI database. The focus of this article is to discuss these changes and highlight several current uses of the TRI database in environmental health research. PMID:9644330

  18. An accidental decapitation resulting from head protruding out of bus.

    PubMed

    Parchake, Manoj Bhausaheb; Tumram, Nilesh K; Umbare, Rahul; Kachare, R V; Dode, C R

    2016-06-01

    Decapitation is the separation of the head from the neck. Accidental decapitation is rare, and very few cases are cited in the literature. In this case, the victim was asleep during an overnight trip with her head sticking out of the window, and she was decapitated by a truck travelling in the opposite direction. Lack of security grilles on windows, high-speed driving, narrow roads and night travel were contributing factors. This case is presented for its rarity and pattern of injuries during the fatal mishap and to consider possible preventive measures. PMID:26857073

  19. Clinical perspectives on osteogenesis imperfecta versus non-accidental injury.

    PubMed

    Pereira, Elaine Maria

    2015-12-01

    Although non-accidental injuries (NAI) are more common in cases of unexplained fractures than rare disorders such as osteogenesis imperfecta (OI), ruling out OI and other medical causes of fracture is always indicated. The majority of OI patients can be diagnosed with the help of family history, physical examination, and radiographic findings. In particular, there are a few radiological findings which are seen more commonly in NAI than in OI which may help guide clinician considerations regarding the probability of either of these diagnoses. At the same time, molecular testing still merits careful consideration in cases with unexplained fractures without obvious additional signs of abuse. PMID:26492946

  20. Methemoglobinemia as a result of accidental lacquer thinner poisoning.

    PubMed

    Singh, Ranju; Vinayagam, Stalin; Vajifdar, Homay

    2012-01-01

    Lacquer thinner, commonly used for removing household paints, is known to contain a mixture of various aromatic hydrocarbons, halogenated hydrocarbons and naptha; if ingested, it may cause methemoglobinemia. We report two cases who presented to us with a history of accidental ingestion of paint thinner. Both the patients had very high levels of methemoglobin and were treated with methylene blue (MB), but did not respond to the MB therapy. One of them received an exchange transfusion followed again by MB and survived. Unfortunately the other patient succumbed to the poisoning. PMID:22557834

  1. ECMO for Cardiac Rescue after Accidental Intravenous Mepivacaine Application

    PubMed Central

    Froehle, Michael; Haas, Nikolaus A.; Kirchner, Guenther; Kececioglu, Deniz; Sandica, Eugen

    2012-01-01

    Mepivacaine is a potent local anaesthetic and used for infiltration and regional anaesthesia in adults and pediatric patients. Intoxications with mepivacaine affect mainly the CNS and the cardiovascular system. We present a case of accidental intravenous mepivacaine application and intoxication of an infant resulting in seizure, broad complex bradyarrhythmia, arterial hypotension and finally cardiac arrest. The patient could be rescued by prolonged resuscitations and a rapid initiation of ECMO and survived without neurological damage. The management strategies of this rare complication including promising other treatment options with lipid emulsions are discussed. PMID:22966472

  2. Investigation of CO2 release pressures in pipeline cracks

    NASA Astrophysics Data System (ADS)

    Gorenz, Paul; Herzog, Nicoleta; Egbers, Christoph

    2013-04-01

    The CCS (Carbon Capture and Storage) technology can prevent or reduce the emissions of carbon dioxide. The main idea of this technology is the segregation and collection of CO2 from facilities with a high emission of that greenhouse gas, i.e. power plants which burn fossil fuels. To segregate CO2 from the exhaust gas the power plant must be upgraded. Up to now there are three possible procedures to segregate the carbon dioxide with different advantages and disadvantages. After segregation the carbon dioxide will be transported by pipeline to a subsurface storage location. As CO2 is at normal conditions (1013,25 Pa; 20 °C) in a gaseous phase state it must be set under high pressure to enter denser phase states to make a more efficient pipeline transport possible. Normally the carbon dioxide is set into the liquid or supercritical phase state by compressor stations which compress the gas up to 15 MPa. The pressure drop makes booster stations along the pipeline necessary which keep the CO2 in a dens phase state. Depending on the compression pressure CO2 can be transported over 300km without any booster station. The goal of this work is the investigation of release pressures in pipeline cracks. The high pressurised pipeline system consists of different parts with different failure probabilities. In most cases corrosion or obsolescence is the reason for pipeline damages. In case of a crack CO2 will escape from the pipeline and disperse into the atmosphere. Due to its nature CO2 can remain unattended for a long time. There are some studies of the CO2 dispersion process, e.g. Mazzoldi et al. (2007, 2008 and 2011) and Wang et al. (2008), but with different assumptions concerning the pipeline release pressures. To give an idea of realistic release pressures investigations with the CFD tool OpenFOAM were carried out and are presented within this work. To cover such a scenario with an accidental release of carbon dioxide a pipeline section with different diameters and

  3. [Accidental extubation in a pediatric intensive care unit].

    PubMed

    Piva, J P; Amantéa, S; Luchese, S; Giugno, K; Maia, T R; Einloft, L

    1995-01-01

    It is an on-going practice in the pediatric ICUs to obtain and to maintain a working artificial airway. Nevertheless this procedure bears not infrequent risks of accidental extubation (AE) which ranges in several services from 0.9 to 3.3 for each 100 days of intubation. The risk factors that are involved in AE are related to: sedation level, age-group, intubation path, and others. The purpose of the authors in this article was to observe the incidence of AE in their service and to compare the relative risk in the rate of AE among orotracheal and nasotracheal intubation population. A prospective study was taken during six months, in which every patients with artificial airway admitted at the PICU of the Santo Antonio Hospital in Porto Alegre (Brazil) was included except those with tracheostomy. The total number of cases were 673 patients-day with artificial airway, with an average of 3.7 patients with tracheal tube per day. In the period there were 18 AE, with a rate of 2.7 AE/ 100 days. The incidence rate of AE in the orotracheal group was 3.1% and 1.6% in the nasotracheal group with no statistically significant difference (p=0.6). The authors concluded that the pathway of intubation in their study does not carry any additional risk in the incidence of accidental extubation. PMID:14689021

  4. Accidental childhood death and the role of the pathologist.

    PubMed

    Byard, R W

    2000-01-01

    The following study provides an overview of accidental childhood death. This study is based on a review of 369 cases of fatal childhood accidents taken from the records of the Department of Histopathology, Women's and Children's Hospital, Adelaide, Australia, over a 34-year period from 1963 to 1996. Data provide information on deaths due to motor vehicle accidents, drownings, accidental asphyxia, burns, poisonings, electrocution, and miscellaneous trauma. In addition, certain categories have undergone further examination, including asphyxial deaths due to unsafe sleeping environments and unsafe eating practices, drowning deaths, and deaths on farms, following identification of significant child safety problems in these areas as part of the "Keeping Your Baby and Child Safe" program. Previously unrecognized dangers to children detected through this program include mesh-sided cots, V-shaped pillows, and certain types of stroller-prams. The production of information pamphlets and packages for parents and the recall of certain dangerous products following recommendations made by pathologists demonstrate that pediatric and forensic pathologists have an important role to play in preventive medicine issues and in formulating public health strategies. PMID:10890925

  5. Laryngeal oedema caused by accidental ingestion of Oil of Wintergreen.

    PubMed

    Botma, M; Colquhoun-Flannery, W; Leighton, S

    2001-05-11

    Oil of Wintergreen (methyl salicylate) is a common ingredient for liniments, ointments and essential oils used in self-treatment of musculoskeletal pain. Its pleasant smell also encourages its use to flavour confectionery. The toxic potential of this preparation is not always fully appreciated by the general public and physicians. To appreciate the danger of this oil it can be compared to aspirin tablets (325 mg dose): one teaspoon (5 ml) of Oil of Wintergreen is equivalent to approximately 7000 mg of salicylate or 21.7 adult aspirin tablets. Ingestion of as little as 4 ml in a child can be fatal. Prevention of accidental ingestion of methyl salicylate containing products can be achieved by keeping the products out of reach of children, using child resistant bottles, restricting the size of the openings of the bottles, appropriate labeling on products and reducing the salicylate content. Immediate action should be taken to treat a patient with accidental poisoning and hospitalisation is needed for monitoring and treatment. The danger of this product should be fully appreciated by both physicians and the general public. We present a case of Oil of Wintergreen poisoning with development of laryngeal oedema as a complication, general information and management issues will also be discussed. PMID:11335011

  6. Preventing Accidental Ignition of Upper-Stage Rocket Motors

    NASA Technical Reports Server (NTRS)

    Hickman, John; Morgan, Herbert; Cooper, Michael; Murbach, Marcus

    2005-01-01

    A report presents a proposal to reduce the risk of accidental ignition of certain upper-stage rocket motors or other high energy hazardous systems. At present, mechanically in-line initiators are used for initiation of many rocket motors and/or other high-energy hazardous systems. Electrical shorts and/or mechanical barriers, which are the basic safety devices in such systems, are typically removed as part of final arming or pad preparations while personnel are present. At this time, static discharge, test equipment malfunction, or incorrect arming techniques can cause premature firing. The proposal calls for a modular out-of-line ignition system incorporating detonating-cord elements, identified as the donor and the acceptor, separated by an air gap. In the safe configuration, the gap would be sealed with two shields, which would prevent an accidental firing of the donor from igniting the system. The shields would be removed to enable normal firing, in which shrapnel generated by the donor would reliably ignite the acceptor to continue the ordnance train. The acceptor would then ignite a through bulkhead initiator (or other similar device), which would ignite the motor or high-energy system. One shield would be remotely operated and would be moved to the armed position when a launch was imminent or conversely returned to the safe position if the launch were postponed. In the event of failure of the remotely operated shield, the other shield could be inserted manually to safe the system.

  7. Savannah River Site Ingestion Pathway Methodology Manual for Airborne Radioactive Releases

    SciTech Connect

    Vincent, A.W. III

    2001-01-03

    This manual documents a recommended methodology for determining the ingestion pathway consequences of hypothetical accidental airborne radiological releases from facilities at the Savannah River Site. Both particulate and tritiated radioactive contaminants are addressed. Other approaches should be applied for evaluation of routine releases.

  8. Radiological Assessment Code System - Meteorological Evaluation of Routine Effluent Releases at Nuclear Power Stations.

    1989-07-31

    Version 00 XOQDOQ-82 evaluates the transport, dispersion, and deposition of effluents released to the atmosphere. Since the program uses meteorological data averaged over long periods of time, it is appropriate for use in environmental impact studies rather than in the analyses of accidental releases.

  9. Fluxes and fate of dissolved methane released at the seafloor at the landward limit of the gas hydrate stability zone offshore western Svalbard

    NASA Astrophysics Data System (ADS)

    Graves, Carolyn A.; Steinle, Lea; Rehder, Gregor; Niemann, Helge; Connelly, Douglas P.; Lowry, David; Fisher, Rebecca E.; Stott, Andrew W.; Sahling, Heiko; James, Rachael H.

    2015-09-01

    Widespread seepage of methane from seafloor sediments offshore Svalbard close to the landward limit of the gas hydrate stability zone (GHSZ) may, in part, be driven by hydrate destabilization due to bottom water warming. To assess whether this methane reaches the atmosphere where it may contribute to further warming, we have undertaken comprehensive surveys of methane in seawater and air on the upper slope and shelf region. Near the GHSZ limit at ˜400 m water depth, methane concentrations are highest close to the seabed, reaching 825 nM. A simple box model of dissolved methane removal from bottom waters by horizontal and vertical mixing and microbially mediated oxidation indicates that ˜60% of methane released at the seafloor is oxidized at depth before it mixes with overlying surface waters. Deep waters are therefore not a significant source of methane to intermediate and surface waters; rather, relatively high methane concentrations in these waters (up to 50 nM) are attributed to isopycnal turbulent mixing with shelf waters. On the shelf, extensive seafloor seepage at <100 m water depth produces methane concentrations of up to 615 nM. The diffusive flux of methane from sea to air in the vicinity of the landward limit of the GHSZ is ˜4-20 μmol m-2 d-1, which is small relative to other Arctic sources. In support of this, analyses of mole fractions and the carbon isotope signature of atmospheric methane above the seeps do not indicate a significant local contribution from the seafloor source.

  10. Atmospheric Dispersion about a Heavy Gas Vapor Detention System.

    NASA Astrophysics Data System (ADS)

    Shin, Seong-Hee

    Dispersion of liquefied natural gas (LNG) in the event of an accidental spill is a major concern in LNG storage and transport safety planning, hazard response, and facility siting. Falcon Series large scale LNG spill experiments were planned by Lawrence Livermore National Laboratory (LLNL) for the Department of Transportation (DOT) and the Gas Research Institute (GRI) as part of a joint government/industry study in 1987 to evaluate the effectiveness of vapor fences as a mitigating technique for accidental release of LNG and to assist in validating wind tunnel and numerical methods for vapor dispersion simulation. Post-field-spill wind-tunnel experiments were performed in Environmental Wind Tunnel (EWT) (1988, 1989) to augment the LNG Vapor Fence Program data obtained during the Falcon Test Series. The program included four different model length scales and two different simulant gases. The purpose of this program is to provide a basis for the analysis of the simulation of physical modeling tests using proper physical modeling techniques and to assist in the development and verification of analytical models. Field data and model data were compared and analyzed by surface pattern comparisons and statistical methods. A layer-averaged slab model developed by Meroney et al. (1988) (FENC23) was expanded to evaluate an enhanced entrainment model proposed for dense gas dispersion including the effect of vapor barriers, and the numerical model was simulated for Falcon tests without the fence and with the vapor fence to examine the effectiveness of vapor detention system on heavy gas dispersion. Model data and the field data were compared with the numerical model data, and degree of similarity between data were assessed.

  11. A case study of pollutants transported from HPCL (vishakhapatnam) accidental fire through synergy of flexpart model and ground-based instruments

    NASA Astrophysics Data System (ADS)

    Wankhede, Tushar

    Tushar Wankhede*, Harish Gadhavi, Amit K. Pandit National Atmospheric Research Laboratory (NARL), Gadanki-517112, Chittoor, A.P. *tushar1771@gmail.com, Mobile: +91-8297152481 A fire at Hindustan Petroleum Corporation Limited (HPCL) in Vishakhapatnam (17.70 ˚N, 83.24˚E) resulted from a gas leak in the salt water cooling tower system. This led to the release of various pollutants like hydrocarbons, black carbon, carbon mono-oxide and carbon dioxide etc(other gases) in just 44 min of fire in system a very huge amount of particles were emitted. The transport of these pollutants has been studied through FLEXPART which is a Lagrangian particle dispersion model having wide range of applications in atmospheric transport modeling. FLEXPART simulation of this accidental fire shows the direction and sensitivity of dispersed pollutants from its source. It was observed that the pollutants reached Gadanki, a rural site located at 13.45 ˚N, 79.18 ˚E in Southern-India. The concentration of pollutant obtained from FLEXPART output we are comparing with ground based instruments data collected at the observation site (Indian Climate Observatory Network-ICON, NARL Gadanki). This case-study provides significant information about the life-time of dispersed pollutants and their long-range transport pattern under the influence of small weather variability en-route from source to receptor. The detailed work of FLEXPART for the Long range transport of the particles will be presented later on in conference.

  12. The evolution of large scale dense gas clouds at Jack Rabbit

    NASA Astrophysics Data System (ADS)

    Huq, Pablo; Spicer, Tom

    2014-11-01

    Typically ammonia and chlorine are stored or transported as pressurized liquefied gas. There have been many accidents involving storage tanks and also accidents during transport. There is a need for accurate evaluation of the hazards associated with accidental releases of ammonia and chlorine which typically result in denser than air clouds which are toxic. The dense gas cloud slumps under the action of gravity into a thin layer with stable density gradients which suppress ambient atmospheric turbulence, and so complicating the physics of mixing. We present similarity analyses of one and two ton experimental releases of ammonia and chlorine at Jack Rabbit. Similarity analysis discriminates inertia-buoyancy and viscous-buoyancy regimes. Sequences of visualizations are used to determine propagation speeds of dense clouds. There is good agreement between observed speeds and the predictions of similarity analysis of the propagation of radial, dense gas clouds. Finally, comparison of one ton with two ton releases for both ammonia and chlorine lead to insights on scaling which are likely to be useful in the design of even larger scale experiments on dense gas clouds arising from similar configurations.

  13. Organic Combustion in the Presence of Ca-Carbonate and Mg-Perchlorate: A Possible Source for the Low Temperature CO2 Release Seen in Mars Phoenix Thermal and Evolved Gas Analyzer Data

    NASA Technical Reports Server (NTRS)

    Archer, Douglas; Ming, D.; Niles, P.; Sutter, B.; Lauer, H.

    2012-01-01

    Two of the most important discoveries of the Phoenix Lander were the detection of approx.0.6% perchlorate [1] and 3-5% carbonate [2] in landing site soils. The Thermal and Evolved Gas Analyzer (TEGA) instrument on the Phoenix lander could heat samples up to approx.1000 C and monitor evolved gases with a mass spectrometer. TEGA detected a low (approx.350 C) and high (approx.750 C) temperature CO2 release. The high temp release was attributed to the thermal decomposition of Ca-carbonate (calcite). The low temperature CO2 release could be due to desorption of CO2, decomposition of a different carbonate mineral, or the combustion of organic material. A new hypothesis has also been proposed that the low temperature CO2 release could be due to the early breakdown of calcite in the presence of the decomposition products of certain perchlorate salts [3]. We have investigated whether or not this new hypothesis is also compatible with organic combustion. Magnesium perchlorate is stable as Mg(ClO4)2-6H2O on the martian surface [4]. During thermal decomposition, this perchlorate salt releases H2O, Cl2, and O2 gases. The Cl2 can react with water to form HCl which then reacts with calcite, releasing CO2 below the standard thermal decomposition temperature of calcite. However, when using concentrations of perchlorate and calcite similar to what was detected by Phoenix, the ratio of high:low temperature CO2 evolved is much larger in the lab, indicating that although this process might contribute to the low temp CO2 release, it cannot account for all of it. While H2O and Cl2 cause calcite decomposition, the O2 evolved during perchlorate decomposition can lead to the combustion of any reduced carbon present in the sample [5]. We investigate the possible contribution of organic molecules to the low temperature CO2 release seen on Mars.

  14. Accidental death of elderly persons under the influence of chlorpheniramine.

    PubMed

    Suzuki, Hideto; Shigeta, Akio; Fukunaga, Tatsushige

    2013-09-01

    Older individuals are susceptible to accident, such as falls, some of which are fatal. In such cases, autopsies and toxicological analysis may be deemed unnecessary, especially if the critical injuries and manner of death can be determined conclusively based on information at the scene and an external investigation. Here, we report the results of two autopsies performed on elderly individuals who died accidentally under the influence of chlorpheniramine. These autopsies revealed valuable additional information. Case 1: A woman in her 70s, who was living alone, was found dead under the stairs in her house. She had no history of a condition that could have led to sudden death. The autopsy revealed a neck fracture, multiple rib fractures, and a coccyx fracture. The histopathological findings showed fat embolisms in numerous small vessels of the interalveolar septum. Toxicological analysis of blood samples revealed the presence of chlorpheniramine (0.41μg/ml). Case 2: A woman in her 70s, who was living alone, was found dead in the bathtub in her house. There was no past medical history other than diabetes mellitus and vertigo. The autopsy revealed hyper-inflated lungs and brown-red fluids in the trachea, but there was no evidence of a pathology or injury that could have induced a loss of consciousness. Toxicological analysis of the fluids in the right thoracic cavity revealed the presence of chlorpheniramine (0.57μg/ml). In both cases, re-examination of the scene after the autopsy revealed the presence of common cold medicine containing chlorpheniramine. The victim may have accidentally overdosed on common cold medicine. This overdose would have been compounded by anti-histamine-induced drowsiness. The present cases suggest that forensic pathologists should always notify physicians/pharmacists of findings pertaining to unexpected drug side effects. Such intervention would prevent many accidental deaths. In addition, each autopsy must be performed in conjunction with

  15. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 2. LLNL Annual Site-specific Data, 1953 - 2003

    SciTech Connect

    Peterson, S R

    2005-03-07

    It is planned to use the tritium dose model, DCART (Doses from Chronic Atmospheric Releases of Tritium), to reconstruct dose to the hypothetical maximally exposed individual from annual routine releases of tritiated water (HTO) and tritiated hydrogen gas (HT) from all Lawrence Livermore National Laboratory (LLNL) facilities and from the Sandia National (SNL) Laboratory's Tritium Research Laboratory over the last fifty years. DCART has been described in Part 1 of ''Historical Doses From Tritiated Water And Tritiated Hydrogen Gas Released To The Atmosphere from Lawrence Livermore National Laboratory (LLNL)'' (UCRL-TR-205083). This report (Part 2) summarizes information about annual routine releases of tritium from LLNL (and SNL) since 1953. Historical records were used to derive facility-specific annual data (e.g., source terms, dilution factors, ambient air concentrations, meteorological data, including absolute humidity and rainfall, etc.) and their associated uncertainty distributions. These data will be used as input to DCART to calculate annual dose for each year of LLNL operations. Sources of information are carefully referenced, and assumptions are documented. Confidence on all data post-1974 is quite high. Prior to that, further adjustment to the estimated uncertainty may have to be made if more information comes to light.

  16. An Experimental Field Dataset with Buoyant, Neutral, and Dense Gas Atmospheric Releases and Model Comparisons in Low-Wind Speed (Diffusion) Conditions

    SciTech Connect

    Veronica E. Wannberg, Gustavious Williams, Patrick Sawyer, and Richard Venedam

    2010-09-01

    Aunique field dataset from a series of low–wind speed experiments, modeling efforts using three commonly used models to replicate these releases, and statistical analysis of how well these models were able to predict the plume concentrations is presented. The experiment was designed to generate a dataset to describe the behavior of gaseous plumes under low-wind conditions and the ability of current, commonly used models to predict these movements. The dataset documents the release and transport of three gases: ammonia (buoyant), ethylene (neutral), and propylene (dense) in low–wind speed (diffusion) conditions. Release rates ranged from 1 to 20 kg h21. Ammonia and ethylene had five 5-min releases each to represent puff releases and five 20-min releases each to represent plume releases. Propylene had five 5-min puffs, six 20-min plumes, and a single 30-min plume. Thirty-two separate releases ranging from 6 to 47 min were conducted, of which only 30 releases generated useful data. The data collected included release rates, atmospheric concentrations to 100 m from the release point, and local meteorological conditions. The diagnostics included nine meteorological stations on 100-m centers and 36 photoionization detectors in a radial pattern. Three current stateof- the-practice models, Aerial locations of Hazardous Atmospheres (ALOHA), Emergency Prediction Information code (EPIcode), and Second-Order Closure Integrated Puff (SCIPUFF), were used to try to duplicate the measured field results. Low wind speeds are difficult to model, and all of the models had difficulty replicating the field measurements. However, the work does show that these models, if used correctly, are conservative (overpredict concentrations) and can be used for safety and emergency planning.

  17. Dose assessment of an accidental exposure at IPNS

    SciTech Connect

    Torres, M.M.C.

    1996-05-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose rates ranged from 550 mrem/min to 2,850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  18. Accidental Intraoral Formalin Injection: A Rare Case Report

    PubMed Central

    Dandriyal, Ramakant; Giri, Kolly Yada; Alam, Sarwar; Singh, Aishwarya Pratap

    2014-01-01

    Formalin is a hazardous chemical that needs cautious handling and special storage. Owing to its disinfectant and fixative (i.e. for preserving pathologic tissue specimens in histopathology) properties, it is widely used in dentistry. Although, the terms formaldehyde and formalin are often confused as being identical, these are different as to the concentrations of the primary component i.e. formaldehyde. In fact, the common fixative available as 10% neutral buffered formalin is actually a 4% solution of formaldehyde (i.e., a 10% solution made from a 37-40% commercially pure formaldehyde solution). This case report describes an unfortunate case of accidental injection instead of local anesthetic, of formalin into the pterygomandibular space in a 35-year old woman during inferior alveolar nerve block for surgical removal of impacted lower right third molar and its successful management by cautious debridement (under both local and general anesthesia) and empirical drug therapy (utilizing analgesics and antibiotics). PMID:25568771

  19. Correcting for accidental correlations in saturated avalanche photodiodes.

    PubMed

    Grieve, J A; Chandrasekara, R; Tang, Z; Cheng, C; Ling, A

    2016-02-22

    In this paper we present a general method for estimating rates of accidental coincidence between a pair of single photon detectors operated within their saturation regimes. By folding the effects of recovery time of both detectors and the detection circuit into an "effective duty cycle" we are able to accomodate complex recovery behaviour at high event rates. As an example, we provide a detailed high-level model for the behaviour of passively quenched avalanche photodiodes, and demonstrate effective background subtraction at rates commonly associated with detector saturation. We show that by post-processing using the updated model, we observe an improvement in polarization correlation visibility from 88.7% to 96.9% in our experimental dataset. This technique will be useful in improving the signal-to-noise ratio in applications which depend on coincidence measurements, especially in situations where rapid changes in flux may cause detector saturation. PMID:26907016

  20. Accidental low velocity atypical missile injury to the head.

    PubMed

    Chattopadhyay, Saurabh

    2008-12-01

    Missile injuries on the head are mostly due to firearms. Atypical missiles may be encountered in case of shrapnel of bomb explosions but rarely because of stones. The present case is a rare case where a stone propelled by the pressure from the rear wheel of a speeding truck on the highway, struck the head of a 7-year-old girl resulting in fatality. Reconstruction of the incident on the basis of history and postmortem findings throws some light on the mechanism. The case is unique as it is the first reported case of an accidental missile injury to the head resulting in fatality without any direct human involvement for propulsion of the projectile. PMID:19259020

  1. CT findings of accidental fish bone ingestion and its complications.

    PubMed

    Venkatesh, Sandeep Halagatti; Venkatanarasimha Karaddi, Nanda Kumar

    2016-01-01

    Fish bone is one of the most common accidentally ingested foreign bodies, and patients commonly present to the emergency department with nonspecific symptoms. Fortunately, most of them are asymptomatic and exit the gastrointestinal tract spontaneously. However, fish bones can get impacted in any part of the aerodigestive tract and cause symptoms. Occasionally, they are asymptomatic initially after ingestion and may present remotely at a later date with serious complications such as gastrointestinal tract perforation, obstruction, and abscess formation. Radiographs are most often negative. High degree of clinical suspicion and familiarity with CT appearance can help to detect fish bone along with any associated complications, and direct further management. We describe and illustrate various CT presentations of ingested fish bone and its complications. PMID:26714057

  2. Dose assessment of an accidental exposure at the IPNS

    SciTech Connect

    Campos Torres, M.M.

    1995-02-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose ranged from 550 mrem/min to 2850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenetic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  3. Evolution Towards Critical Fluctuations in a System of Accidental Pathogens

    NASA Astrophysics Data System (ADS)

    Ghaffari, Peyman; Jansen, Vincent; Stollenwerk, Nico

    2011-09-01

    Some time ago a model for accidental pathogens was developed to describe large fluctuations in the epidemiology of some diseases where the pathogen mostly lives with its host as a commensal and only rarely causes disease, leading to a disadvantage of the mutants which cause disease more often. By now the simplest version of this scenario is known as Stollenwerk-Jansen (SJ) model, showing that the critical exponents of the large fluctuations are of the type of the voter model (which by itself has an evolutionary biologists predecessor) but no further attempt was made there to investigate in more detail the mechanism leading the system to evolve towards small pathogenicity. We investigate an extended version of the SJ model, the SJ model version II in which we find the system to evolve to low pathogenicity causing large critical fluctuations without tuning the control parameter, a self-organization of criticality.

  4. CT findings of accidental fish bone ingestion and its complications

    PubMed Central

    Venkatesh, Sandeep Halagatti; Karaddi, Nanda Kumar Venkatanarasimha

    2016-01-01

    Fish bone is one of the most common accidentally ingested foreign bodies, and patients commonly present to the emergency department with nonspecific symptoms. Fortunately, most of them are asymptomatic and exit the gastrointestinal tract spontaneously. However, fish bones can get impacted in any part of the aerodigestive tract and cause symptoms. Occasionally, they are asymptomatic initially after ingestion and may present remotely at a later date with serious complications such as gastrointestinal tract perforation, obstruction, and abscess formation. Radiographs are most often negative. High degree of clinical suspicion and familiarity with CT appearance can help to detect fish bone along with any associated complications, and direct further management. We describe and illustrate various CT presentations of ingested fish bone and its complications. PMID:26714057

  5. An atmospheric tritium release database for model comparisons

    SciTech Connect

    Murphy, C.E. Jr.; Wortham, G.R.

    1997-10-13

    A database of vegetation, soil, and air tritium concentrations at gridded coordinate locations following nine accidental atmospheric releases is described. The concentration data is supported by climatological data taken during and immediately after the releases. In six cases, the release data is supplemented with meteorological data taken at seven towers scattered throughout the immediate area of the releases and data from a single television tower instrumented at eight heights. While none of the releases caused a significant dose to the public, the data collected is valuable for comparison with the results of tritium transport models used for risk assessment. The largest, potential off-site dose from any of the releases was calculated to be 1.6 mrem. The population dose from this same release was 46 person-rem which represents 0.04 percent of the natural background dose to the population in the path of the release.

  6. Involving Parents in Indicated Early Intervention for Childhood PTSD Following Accidental Injury

    ERIC Educational Resources Information Center

    Cobham, Vanessa E.; March, Sonja; De Young, Alexandra; Leeson, Fiona; Nixon, Reginald; McDermott, Brett; Kenardy, Justin

    2012-01-01

    Accidental injuries represent the most common type of traumatic event to which a youth is likely to be exposed. While the majority of youth who experience an accidental injury will recover spontaneously, a significant proportion will go on to develop Post-Traumatic Stress Disorder (PTSD). And yet, there is little published treatment outcome…

  7. Accidentes en plantas nucleares de electricidad y el riesgo de cáncer

    Cancer.gov

    Hoja informativa acerca de los riesgos del cáncer asociados con accidentes en plantas nucleares de electricidad. Incluye información para pacientes con cáncer que viven en una zona que puede haber sido afectada por un accidente en una planta nuclear.

  8. Two Cases of Accidental Injection of Epinephrine into a Digit Treated with Subcutaneous Phentolamine Injections

    PubMed Central

    Bodkin, Ryan P.; Acquisto, Nicole M.; Wiegand, Timothy J.

    2013-01-01

    Accidental injection into the digit from an epinephrine autoinjection device can cause discoloration, pain, and paresthesias. Although loss of digit is rare, treatment in the emergency department is commonly aimed at vasodilation of the affected tissue. We report two cases of accidental injection of epinephrine into the digits that were successfully treated with subcutaneous phentolamine injection with no adverse events. PMID:24024046

  9. Accidental Durotomy in Minimally Invasive Transforaminal Lumbar Interbody Fusion: Frequency, Risk Factors, and Management

    PubMed Central

    Volz, Florian; Krüger, Marie T.; Kogias, Evangelos; Rölz, Roland; Sircar, Ronen; Hubbe, Ulrich

    2015-01-01

    Purpose. To assess the frequency, risk factors, and management of accidental durotomy in minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). Methods. This single-center study retrospectively investigates 372 patients who underwent MIS TLIF and were mobilized within 24 hours after surgery. The frequency of accidental durotomies, intraoperative closure technique, body mass index, and history of previous surgery was recorded. Results. We identified 32 accidental durotomies in 514 MIS TLIF levels (6.2%). Analysis showed a statistically significant relation of accidental durotomies to overweight patients (body mass index ≥25 kg/m2; P = 0.0493). Patient age older than 65 years tended to be a positive predictor for accidental durotomies (P = 0.0657). Mobilizing patients on the first postoperative day, we observed no durotomy-associated complications. Conclusions. The frequency of accidental durotomies in MIS TLIF is low, with overweight being a risk factor for accidental durotomies. The minimally invasive approach seems to minimize durotomy-associated complications (CSF leakage, pseudomeningocele) because of the limited dead space in the soft tissue. Patients with accidental durotomy can usually be mobilized within 24 hours after MIS TLIF without increased risk. The minimally invasive TLIF technique might thus be beneficial in the prevention of postoperative immobilization-associated complications such as venous thromboembolism. This trial is registered with DRKS00006135. PMID:26075294

  10. 21 CFR 369.9 - General warnings re accidental ingestion by children.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false General warnings re accidental ingestion by... SERVICES (CONTINUED) DRUGS FOR HUMAN USE INTERPRETATIVE STATEMENTS RE WARNINGS ON DRUGS AND DEVICES FOR OVER-THE-COUNTER SALE Definitions and Interpretations § 369.9 General warnings re accidental...

  11. Characterization and Comparison of Injuries Caused by Accidental and Non-accidental Blunt Force Trauma in Dogs and Cats.

    PubMed

    Intarapanich, Nida P; McCobb, Emily C; Reisman, Robert W; Rozanski, Elizabeth A; Intarapanich, Pichai P

    2016-07-01

    Motor vehicle accidents (MVA) are often difficult to distinguish from non-accidental injury (NAI). This retrospective case-control study compared animals with known MVA trauma against those with known NAI. Medical records of 426 dogs and cats treated after MVA and 50 after NAI were evaluated. Injuries significantly associated with MVA were pelvic fractures, pneumothorax, pulmonary contusion, abrasions, and degloving wounds. Injuries associated with NAI were fractures of the skull, teeth, vertebrae, and ribs, scleral hemorrhage, damage to claws, and evidence of older fractures. Odds ratios are reported for these injuries. MVA rib fractures were found to occur in clusters on one side of the body, with cranial ribs more likely to fracture, while NAI rib fractures were found to occur bilaterally with no cranial-caudal pattern. Establishing evidence-based patterns of injury may help clinicians differentiate causes of trauma and may aid in the documentation and prosecution of animal abuse. PMID:27364279

  12. Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities.

    PubMed

    Drollette, Brian D; Hoelzer, Kathrin; Warner, Nathaniel R; Darrah, Thomas H; Karatum, Osman; O'Connor, Megan P; Nelson, Robert K; Fernandez, Loretta A; Reddy, Christopher M; Vengosh, Avner; Jackson, Robert B; Elsner, Martin; Plata, Desiree L

    2015-10-27

    Hundreds of organic chemicals are used during natural gas extraction via high-volume hydraulic fracturing (HVHF). However, it is unclear whether these chemicals, injected into deep shale horizons, reach shallow groundwater aquifers and affect local water quality, either from those deep HVHF injection sites or from the surface or shallow subsurface. Here, we report detectable levels of organic compounds in shallow groundwater samples from private residential wells overlying the Marcellus Shale in northeastern Pennsylvania. Analyses of purgeable and extractable organic compounds from 64 groundwater samples revealed trace levels of volatile organic compounds, well below the Environmental Protection Agency's maximum contaminant levels, and low levels of both gasoline range (0-8 ppb) and diesel range organic compounds (DRO; 0-157 ppb). A compound-specific analysis revealed the presence of bis(2-ethylhexyl) phthalate, which is a disclosed HVHF additive, that was notably absent in a representative geogenic water sample and field blanks. Pairing these analyses with (i) inorganic chemical fingerprinting of deep saline groundwater, (ii) characteristic noble gas isotopes, and (iii) spatial relationships between active shale gas extraction wells and wells with disclosed environmental health and safety violations, we differentiate between a chemical signature associated with naturally occurring saline groundwater and one associated with alternative anthropogenic routes from the surface (e.g., accidental spills or leaks). The data support a transport mechanism of DRO to groundwater via accidental release of fracturing fluid chemicals derived from the surface rather than subsurface flow of these fluids from the underlying shale formation. PMID:26460018

  13. 36 CFR 1230.10 - Who is responsible for preventing the unlawful or accidental removal, defacing, alteration, or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... preventing the unlawful or accidental removal, defacing, alteration, or destruction of records? 1230.10... responsible for preventing the unlawful or accidental removal, defacing, alteration, or destruction of records? The heads of Federal agencies must: (a) Prevent the unlawful or accidental removal,...

  14. Quantification of nerve agent VX-butyrylcholinesterase adduct biomarker from an accidental exposure.

    PubMed

    Solano, Maria I; Thomas, Jerry D; Taylor, James T; McGuire, Jeffrey M; Jakubowski, Edward M; Thomson, Sandra A; Maggio, Vincent L; Holland, Kerry E; Smith, J Richard; Capacio, Benedict; Woolfitt, Adrian R; Ashley, David L; Barr, John R

    2008-01-01

    The lack of data in the open literature on human exposure to the nerve agent O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothioate (VX) gives a special relevance to the data presented in this study in which we report the quantification of VX-butyrylcholinesterase adduct from a relatively low-level accidental human exposure. The samples were analyzed by gas chromatography-high resolution mass spectrometry using the fluoride ion regeneration method for the quantification of multiple nerve agents including VX. Six human plasma samples from the same individual were collected after the patient had been treated once with oxime immediately after exhibiting signs of exposure. Detection limits of approximately 5.5 pg/mL plasma were achieved for the G-analogue of VX (G-VX). Levels of the G-VX ranged from 81.4 pg/mL on the first day after the exposure to 6.9 pg/mL in the sample taken 27 days after the exposure. Based on the reported concentration of human butyrylcholinesterase in plasma of approximately 80 nM, it can be calculated that inhibition levels of >or= 0.05% of BuChE can be accurately quantified. These data further indicate that the fluoride ion regeneration method is a potentially powerful tool that can be used to assess low-level exposure to VX. PMID:18269796

  15. Short DNA sequences inserted for gene targeting can accidentally interfere with off-target gene expression.

    PubMed

    Meier, Ingo D; Bernreuther, Christian; Tilling, Thomas; Neidhardt, John; Wong, Yong Wee; Schulze, Christian; Streichert, Thomas; Schachner, Melitta

    2010-06-01

    Targeting of genes in mice, a key approach to study development and disease, often leaves a neo cassette, loxP, or FRT sites inserted in the mouse genome. Insertion of neo can influence the expression of neighboring genes, but similar effects have not been reported for loxP sites. We therefore performed microarray analyses of mice in which the Ncam or the Tnr gene were targeted either by insertion of neo or loxP/FRT sites. In the case of Ncam, neo, but not loxP/FRT insertion, led to a 2-fold reduction in mRNA levels of 3 genes located at distances between 0.2 and 3.1 Mb from the target. In contrast, after introduction of loxP/FRT sites into introns of Tnr, we observed a 2.5- to 4-fold reduction in the transcript level of the Gas5 gene, 1.1 Mb away from Tnr, most probably due to disruption of a conserved regulatory element in Tnr. Insertion of short DNA sequences such as loxP/FRT can thus influence off-target mRNA levels if these sites are accidentally placed into regulatory elements. Our results imply that conditional knockout mice should be analyzed for genomic positional side effects that may influence the animals' phenotypes. PMID:20110269

  16. Small and Large-scale Drivers of Denitrification Patterns in "Accidental" Urban Wetlands in Phoenix, Arizona

    NASA Astrophysics Data System (ADS)

    Suchy, A. K.; Palta, M. M.; Childers, D. L.; Stromberg, J. C.

    2014-12-01

    Understanding spatial and temporal patterns of microbial conversion of nitrate (NO3-) to nitrogen (N) gas (denitrification) is important for predicting permanent losses of reactive N from systems. In many landscapes, wetlands serve as hotpots of denitrification by providing optimal condition for denitrifiers (sub-oxic, carbon-rich sediments). Much research on denitrification has occurred in non-urban or highly managed urban wetlands. However, in urban landscapes N-rich stormwater is often discharged into areas not designed or managed to reduce N loads. "Accidental" wetlands forming at these outfalls may have the capacity to remove NO3-; however, these "accidental" urban wetlands can contain novel soils and vegetation, and are subject to unique hydrologic conditions that could create spatial and temporal patterns of denitrification that differ from those predicted in non-urban counterparts. We performed denitrification enzyme assays (measuring denitrification potential, or DP) on soil samples taken from nine wetlands forming at storm drain outfalls in Phoenix, AZ. The wetlands ranged from perennially flooded, to intermittently flooded (~9 months/year), to ephemerally flooded (2-3 weeks/year). To assess spatial variation in carbon availability to denitrifiers, samples were taken from 3-4 dominant vegetation patch types within each wetland. To assess temporal variation in DP, samples were taken across three seasons differing in rainfall pattern. We found small- and large-scale spatiotemporal patterns in DP that have important implications for management of urban wetlands for stormwater quality. DP varied among plant patches and was typically highest in patches of Ludwigia peploides, indicating that plant species type may mediate within-wetland variations in carbon availability, and therefore NO3- removal capacity. We found a range of responses in DP among wetlands to season, which appeared to be driven in part by flood regime: DP in perennially-flooded wetlands was

  17. Simple Techniques For Assessing Impacts Of Oil And Gas Operations On Public Lands: A Field Evaluation Of A Photoionization Detector (PID) At A Condensate Release Site, Padre Island National Seashore, Texas

    USGS Publications Warehouse

    Otton, James K.; Zielinski, Robert A.

    2001-01-01

    Simple, cost-effective techniques are needed for land managers to assess the environmental impacts of oil and gas production activities on public lands, so that sites may be prioritized for remediation or for further, more formal assessment. Field-portable instruments provide real-time data and allow the field investigator to extend an assessment beyond simply locating and mapping obvious disturbances. Field investigators can examine sites for the presence of hydrocarbons in the subsurface using a soil auger and a photoionization detector (PID). The PID measures volatile organic compounds (VOC) in soil gases. This allows detection of hydrocarbons in the shallow subsurface near areas of obvious oil-stained soils, oil in pits, or dead vegetation. Remnants of a condensate release occur in sandy soils at a production site on the Padre Island National Seashore in south Texas. Dead vegetation had been observed by National Park Service personnel in the release area several years prior to our visit. The site is located several miles south of the Malaquite Beach Campground. In early 2001, we sampled soil gases for VOCs in the area believed to have received the condensate. Our purpose in this investigation was: 1) to establish what sampling techniques might be effective in sandy soils with a shallow water and contrast them with techniques used in an earlier study; and 2) delineate the probable area of condensate release. Our field results show that sealing the auger hole with a clear, rigid plastic tube capped at the top end and sampling the soil gas through a small hole in the cap increases the soil VOC gas signature, compared to sampling soil gases in the bottom of an open hole. This sealed-tube sampling method increases the contrast between the VOC levels within a contaminated area and adjacent background areas. The tube allows the PID air pump to draw soil gas from the volume of soil surrounding the open hole below the tube in a zone less influenced by atmospheric air

  18. Relocation impacts of a major release from SRTC

    SciTech Connect

    Blanchard, A.; Thompson, E.A.; Thompson, J.M.

    1999-06-01

    The relocation impacts of an accidental release, scenario 1-RD-3 , are evaluated for the Savannah River Technology Center. The extent of the area potentially contaminated to a level that would result in doses exceeding the relocation protective action guide(PAG)is calculated. The maximum calculated distance downwind from the accident at which the relocation PAG is exceeded is also determined. The consequences of the particulate portion of the release are evaluated using the HOTSPOT model and an EXCEL spreadsheet. The consequences of the tritium release are evaluated using UFOTRI.

  19. Role of the surgeon in non-accidental trauma.

    PubMed

    Naik-Mathuria, Bindi; Akinkuotu, Adesola; Wesson, David

    2015-07-01

    Non-accidental trauma (NAT) represents a significant cause of morbidity and mortality in the pediatric population. The management of these patients often involves many care providers including the surgeon. Victims of NAT often present with multiple injuries and as such should be treated as trauma patients with complete trauma evaluation including primary, secondary and tertiary surveys. Common injury patterns in NAT include extremity fractures, closed head injury and intra-abdominal injury. Brain imaging is of importance to rule out acute or sub-acute intracranial hemorrhage. Children under the age of 5 years with acute intracranial pathology should also be evaluated by an ophthalmologist to rule out retinal hemorrhages, which are considered pathognomonic for child abuse from violent shaking. In instances when abdominal injury is suspected, prompt evaluation by a surgeon is recommended along with CT imaging. Finding of extremity fractures should prompt evaluation by an orthopedic surgeon. At our institution, all patients with suspected NAT are admitted to the pediatric surgery service for complete evaluation and management. We encourage other pediatric trauma centers to employ a similar approach so that these complicated patients are managed safely and effectively. PMID:25772160

  20. Pneumonitis and pneumatoceles following accidental hydrocarbon aspiration in children.

    PubMed

    Thalhammer, Gabriela H; Eber, Ernst; Zach, Maximilian S

    2005-02-01

    Accidental ingestion and aspiration of hydrocarbons in children are common. Among the various clinical and pathological manifestations of hydrocarbon (HC) poisoning, pneumonitis is the most significant and occurs in up to 40% of children, whereas formation of pneumatoceles is believed to be a rare event. We report two children with HC pneumonitis and pneumatoceles as a reversible complication after ingestion and aspiration of lamp oil with very low viscosity. Patient 1, a 21-month-old boy, started to cough and developed tachypnea, sternal retractions and mild cyanosis immediately after aspiration. Patient 2, a 24-month-old girl, was asymptomatic during the first days after the accident; subsequently, she started to cough and developed fever, dyspnea and chest pain. Chest x-ray and computed tomography revealed multiple patchy infiltrates in both cases; after several days, these confluent infiltrates developed into pneumatoceles. Both children were treated with antibiotics and steroids. They recovered within three and four weeks, respectively, with complete remission of the radiologic abnormalities and had an uneventful follow-up after discharge. PMID:15847196

  1. High mortality due to accidental salinomycin intoxication in sheep

    PubMed Central

    Eisapour, Hamed; Erfani, Amir Mehdi; Kalantary, Amir Ali; Amoli, Jamileh Salar; Mozafari, Morteza

    2014-01-01

    In February 2012, 100% mortality was reported in a herd with 79 local sheep that were kept around of Abhar, Northwest of Iran. The ration for adult sheep was daily mixed (40 kg straw, 25 kg wheat and 2 kg Vit-C premix) and accidentally 1 500 g of salinomycin (Salinomycin 12% Premix; Aras Bazar Laboratories, Iran) had been added to the ration (22388 mg/kg = 22388 ppm) and overnight was fed to herd. At the morning, 78 sheep were founded dead and one of them showed convulsive seizures. Postmortem examination revealed pulmonary congestion and edema, hemorrhages in abomasum, large pale kidney and white streak lines in myocardium. Main histopathologic lesions were extensive subepicardial and intercardiomyofibers hemorrhages, extensive cardiomyolysis and myocarditis in heart, severe hyperemia and extensive acute tubular necrosis (ATN) in kidneys and focal necrosis and retention of bile cholangitis in the liver. In this study, on the basis of the history, observation of the ionophore remnant in the ration, clinical signs, gross and histopathological findings, acute salinomycin intoxication is definitely diagnosed. PMID:26109896

  2. Assessment of accidental intakes of uranyl acetylacetonate (UAA)

    SciTech Connect

    Fisher, D.R.; Briant, J.K.

    1993-12-01

    Uranyl acetylacetonate (UAA) is an organic complex of uranium used for military applications as a chemical catalyst in high explosives. It is prepared from depleted uranium metal (in lots of 5 kg to 7 kg) by dissolution in nitric acid, neutralization, and complexation with 2,4-pentanedione; the precipitate is dissolved in benzene and recrystallized, dried, ground, and packaged. About six workers at a small chemical company were exposed over a period of time to UAA powders during routine preparation and packaging of the uranium catalyst. The dissolution characteristics of the inhaled material were unknown and could not be determined from the published scientific literature. A 1.05-g sample of UAA powder was obtained from the responsible regulatory authority for further study to determine its chemical composition, and for dissolution in simulated lung fluid. We found the solubility of UAA to be equivalent to a mixture of 52% ICRP class D and 48% ICRP class W material. The annual limit on intake and the derived air concentration for radiological protection were estimated from this result for airborne exposure to UAA. A recycling biokinetic model was used to estimate both material-specific variations in urinary excretion rates and lung retention with time after accidental intakes. This study provides new information for evaluating future exposures to UAA.

  3. Non-Accidental Health Impacts of Wildfire Smoke

    PubMed Central

    Youssouf, Hassani; Liousse, Catherine; Roblou, Laurent; Assamoi, Eric-Michel; Salonen, Raimo O.; Maesano, Cara; Banerjee, Soutrik; Annesi-Maesano, Isabella

    2014-01-01

    Wildfires take a heavy toll on human health worldwide. Climate change may increase the risk of wildfire frequency. Therefore, in view of adapted preventive actions, there is an urgent need to further understand the health effects and public awareness of wildfires. We conducted a systematic review of non-accidental health impacts of wildfire and incorporated lessons learned from recent experiences. Based on the literature, various studies have established the relationship between one of the major components of wildfire, particulate matter (particles with diameter less than 10 µm (PM10) and less than 2.5 µm (PM2.5)) and cardiorespiratory symptoms in terms of Emergency Rooms visits and hospital admissions. Associations between wildfire emissions and various subclinical effects have also been established. However, few relationships between wildfire emissions and mortality have been observed. Certain segments of the population may be particularly vulnerable to smoke-related health risks. Among them, people with pre-existing cardiopulmonary conditions, the elderly, smokers and, for professional reasons, firefighters. Potential action mechanisms have been highlighted. Overall, more research is needed to better understand health impact of wildfire exposure. PMID:25405597

  4. Kinematics and kinetics of an accidental lateral ankle sprain.

    PubMed

    Kristianslund, Eirik; Bahr, Roald; Krosshaug, Tron

    2011-09-23

    Ankle sprains are common during sporting activities and can have serious consequences. Understanding of injury mechanisms is essential to prevent injuries, but only two previous studies have provided detailed descriptions of the kinematics of lateral ankle sprains and measures of kinetics are missing. In the present study a female handball player accidentally sprained her ankle during sidestep cutting in a motion analysis laboratory. Kinematics and kinetics were calculated from 240 Hz recordings with a full-body marker setup. The injury trial was compared with two previous (non-injury) trials. The injury trial showed a sudden increase in inversion and internal rotation that peaked between 130 and 180 ms after initial contact. We observed an attempted unloading of the foot from 80 ms after initial contact. As the inversion and internal rotation progressed, the loads were likely to exceed injury threshold between 130 and 180 ms. There was a considerable amount of dorsiflexion in the injury trial compared to neutral flexion in the control trials, similar to the previously published kinematical descriptions of lateral ankle sprains. The present study also adds valuable kinetic information that improves understanding of the injury mechanism. PMID:21824618

  5. Sevoflurane as a therapy for acute chlorine gas exposure in an austere healthcare environment: a case report.

    PubMed

    Bellenger, Sarah R; Frizzi, James D

    2014-06-01

    Chlorine is a common agent found worldwide in industrial and household applications. This element is found everywhere and anywhere around the globe. Because of its ubiquitous nature in the world, chlorine-injured patients may be expected at all medical facilities, from large-urban to small-community to austere-tent facilities. Chlorine has been used as a chemical weapon since 1915 and has been accidentally released in transport, storage, and use, causing industrial accidents worldwide. A patient with a history of severe chlorine inhalational injury sustained 2 chlorine gas exposures within 48 hours. The patient was treated with intubation, mechanical ventilation, and directed therapies for severe injury by chlorine gas inhalation. Sevoflurane has a role in treating chlorine inhalation injury. Additional therapies are possible, some of which are not available in remote locations. PMID:25109161

  6. Aerobic biodegradability of methyldiethanolamine (MDEA) used in natural gas sweetening plants in batch tests and continuous flow experiments.

    PubMed

    Fürhacker, M; Pressl, A; Allabashi, R

    2003-09-01

    Mixtures of different amines including tertiary amines (methyldiethanolamine, MDEA) are commonly used for the removal of CO2 from gas mixtures or in gas sweetening processes for the extraction of CO2 and H2S. The absorber solutions used can be released into the industrial waste water due to continuous substitution of degraded MDEA, periodically cleaning processes or an accidental spill. In this study, the aerobic biodegradability of MDEA was investigated in a standardised batch test and a continuous flow experiment (40 l/d). The results of the batch test indicated that the MDEA-solution was non-biodegradable during the test period of 28 days, whereas the continuous flow experiments showed biodegradation of more than 96% based on TOC-measurements. This was probably due to the adaptation of the microorganisms to this particular waste water contamination during continuous flow experiment. PMID:12871741

  7. Benzene release. status report

    SciTech Connect

    Dworjanyn, L.O.; Rappe, K.G.; Gauglitz, P.A.

    1997-11-04

    Scoping benzene release measurements were conducted on 4 wt percent KTPB `DEMO` formulation slurry using a round, flat bottomed 100-mL flask containing 75 mL slurry. The slurry was agitated with a magnetic stirrer bar to keep the surface refreshed without creating a vortex. Benzene release measurements were made by purging the vapor space at a constant rate and analyzing for benzene by gas chromatography with automatic data acquisition. Some of the data have been rounded or simplified in view of the scoping nature of this study.

  8. Instrument adjustment knob locks to prevent accidental maladjustment

    NASA Technical Reports Server (NTRS)

    1964-01-01

    A device, incorporating a collar with a hexagonal opening which fits snugly over a hexagonal nut used to engage instrument panel components, keeps the adjustment knob locked. A quick release mechanism frees the knob for rotational adjustment.

  9. Toxic release inventory, 1989. Magnetic tape documentation

    SciTech Connect

    Not Available

    1989-01-01

    Section 313 of the Emergency Planning and Community Right-to-Know Act (also known as Title III) of the Superfund Amendments and Reauthorization Act (SARA) of 1986 (Public Law 99-499) requires EPA to establish an inventory of toxic chemical emissions from certain facilities. Facilities subject to this reporting requirement are required to complete a Toxic Chemical Release Form (Form R) for specified chemicals. The form must be submitted to EPA and those state officials designated by the govenor, on or before July 1, 1988, and annually thereafter on July 1. The reports should reflect releases during the preceding calendar year. The purpose of the reporting requirement is to inform the public and government officials about routine and accidental releases of toxic chemicals to the environment. It will also assist in research and the development of regulations, guidelines, and standards.

  10. Estimation of Accumulated Dose to Residents due to Tritium Release from Fusion Facilities

    SciTech Connect

    Saito, Masahiro

    2005-07-15

    The computer program TriStat (Tritium dose assessment for stationary release) was used to estimate the human dose under stationary release and to obtain a conservative estimate of the dose after an accidental release as well. The atmospheric behavior of tritium is described by a Gaussian dispersion model. The tritium concentration in the atmosphere, soil, vegetables and cereals were estimated on the basis of tritium inventory of the facility and the release rate of tritium. In the model description, the specific tritium concentrations for the free water component and the organic component are essential. The food chain for humans was modeled by assuming a forage compartment, a plant compartment and an animal compartment. In the model, a virtual plant and a virtual animal were defined.The calculation revealed that the exchange of HTO between atmosphere and plant leaves has a critical role for increasing the human dose both for stationary and accidental release of tritium.

  11. 60,000 U.S. Kids Treated for Accidental Medicine Poisoning a Year

    MedlinePlus

    ... medlineplus/news/fullstory_157875.html 60,000 U.S. Kids Treated for Accidental Medicine Poisoning a Year Toddlers ... because of medicine-related poisoning, according to Safe Kids Worldwide. And nearly every minute each day a ...

  12. Accidental hanging deaths in children in Konya, Turkey between 1998 and 2007.

    PubMed

    Dogan, Kamil H; Demirci, Serafettin; Erkol, Zerrin; Gulmen, Mete K

    2010-05-01

    In general, hanging cases are the result of suicide, and accidental and homicidal hanging cases are rarely seen. This study retrospectively investigated 4571 death examinations and autopsies that were performed at The Konya Branch of the Forensic Medicine Council (Turkey) between 1998 and 2007; hanging was involved in 201 (6.5%) of the cases. There were a total of 13 accidental hanging cases, where 12 of these involved children. In seven of the cases, the accidental hanging involved a scarf that wraps around swing-like cradles and is intended to prevent infants from falling down. It was concluded that accidental hanging deaths can be reduced by replacing swing-like cradles with cribs that are designed for children, removing ropes in and around the house, and preventing children from reaching and/or playing with rope-like objects. PMID:20202070

  13. Accidental ingestion of a component of a fixed orthodontic appliance--a case report.

    PubMed

    Quick, A N; Harris, A M P

    2002-03-01

    Most dental patients are treated in the supine position, enhancing the risk of accidental aspiration or swallowing of foreign objects. This article presents a case report of an orthodontic patient who accidentally ingested a section of orthodontic wire and coil spring from a fixed expansion device placed in the maxillary dental arch. Some guidelines for the prevention of such occurrences in the practice and at home, and possible courses of remedial action, are discussed. PMID:12061146

  14. Laboratory-Acquired Parasitic Infections from Accidental Exposures

    PubMed Central

    Herwaldt, Barbara L.

    2001-01-01

    Parasitic diseases are receiving increasing attention in developed countries in part because of their importance in travelers, immigrants, and immunocompromised persons. The main purpose of this review is to educate laboratorians, the primary readership, and health care workers, the secondary readership, about the potential hazards of handling specimens that contain viable parasites and about the diseases that can result. This is accomplished partly through discussion of the occupationally acquired cases of parasitic infections that have been reported, focusing for each case on the type of accident that resulted in infection, the length of the incubation period, the clinical manifestations that developed, and the means by which infection was detected. The article focuses on the cases of infection with the protozoa that cause leishmaniasis, malaria, toxoplasmosis, Chagas' disease (American trypanosomiasis), and African trypanosomiasis. Data about 164 such cases are discussed, as are data about cases caused by intestinal protozoa and by helminths. Of the 105 case-patients infected with blood and tissue protozoa who either recalled an accident or for whom the likely route of transmission could be presumed, 47 (44.8%) had percutaneous exposure via a contaminated needle or other sharp object. Some accidents were directly linked to poor laboratory practices (e.g., recapping a needle or working barehanded). To decrease the likelihood of accidental exposures, persons who could be exposed to pathogenic parasites must be thoroughly instructed in safety precautions before they begin to work and through ongoing training programs. Protocols should be provided for handling specimens that could contain viable organisms, using protective clothing and equipment, dealing with spills of infectious organisms, and responding to accidents. Special care should be exercised when using needles and other sharp objects. PMID:11585780

  15. Persistent Seroconversion after Accidental Eye Exposure to Calcifying Nanoparticles

    NASA Technical Reports Server (NTRS)

    Ciftcioglu, Neva; Aho, Katja M.; McKay, David S.; Kajander, E. Olavi

    2007-01-01

    Biosafety of nanomaterials has attracted much attention recently. We report here a case where accidental human eye exposure to biogenic nanosized calcium phosphate in the form of calcifying nanoparticles (CNP) raised a strong IgG immune response against proteins carried by CNP. The antibody titer has persisted over ten years at the high level. The IgG was detected by ELISA using CNPs propagated in media containing bovine and human serum as antigen. The exposure incident occurred to a woman scientist (WS) at a research laboratory in Finland at 1993. CNP, also termed "nanobacteria", is a unique self-replicating agent that has not been fully characterized and no data on biohazards were available at that time. Before the accident, her serum samples were negative for both CNP antigen and anti-CNP antibody using specific ELISA tests (Nanobac Oy, Kuopio, Finland). The accident occurred while WS was harvesting CNP cultures. Due to a high pressure in pipetting, CNP pellet splashed into her right eye. Both eyes were immediately washed with water and saline. The following days there was irritation and redness in the right eye. These symptoms disappeared within two weeks without any treatment. Three months after the accident, blood and urine samples of WS were tested for CNP cultures (2), CNP-specific ELISA tests, and blood cell counts. Blood cell counts were normal, CNP antigen and culture tests were negative. A high IgG anti-CNP antibody titer was detected (see Figure). The antibodies of this person have been used thereafter as positive control and standard in ELISA manufacturing (Nano-Sero IgG ELISA, Nanobac Oy, Kuopio, Finland).

  16. PARAMETRIC EFFECTS OF ANTI-FOAM COMPOSITION, SIMULANT PROPERTIES AND NOBLE METALS ON THE GAS HOLDUP AND RELEASE OF A NON-NEWTONIAN WASTE SLURRY SIMULANT

    SciTech Connect

    Guerrero, H; Charles Crawford, C; Mark Fowley, M

    2008-08-07

    Gas holdup tests were performed in bench-scale and small-scale mechanically-agitated mixing systems at the Savannah River National Laboratory (SRNL) for a simulant of waste from the Hanford Tank 241-AZ-101. These featured additions of DOW Corning Q2-3183A anti-foam agent. Results indicated that this anti-foam agent (AFA) increased gas holdup in the waste simulant by about a factor of four and, counter-intuitively, that the holdup increased as the non-newtonian simulant shear strength decreased (apparent viscosity decreased). Such results raised the potential of increased flammable gas retention in Hanford Waste Treatment and Immobilization Plant (WTP) vessels mixed by air sparging and pulse-jet mixers (PJMs) during a Design Basis Event (DBE). Additional testing was performed to determine the effects of simulant properties, composition of alternate AFAs, and presence of trace noble metals. Key results are that: (1) Increased gas holdup resulting from addition of Q2-3183A is due to a decrease in surface tension that supports small bubbles which have low rise velocities. (2) Dow Corning 1520-US AFA shows it to be a viable replacement to Dow Corning Q2-3183A AFA. This alternative AFA, however, requires significantly higher dosage for the same anti-foam function. (3) Addition of noble metals to the AZ-101 waste simulant does not produce a catalytic gas retention effect with the AFA.

  17. Use of multiple cell and tissue-level biomarkers in mussels collected along two gas fields in the northern Adriatic Sea as a tool for long term environmental monitoring.

    PubMed

    Gomiero, A; Volpato, E; Nasci, C; Perra, G; Viarengo, A; Dagnino, A; Spagnolo, A; Fabi, G

    2015-04-15

    As a consequence of the growing global demand of energy supplies, intense oil and gas exploration and exploitation programs have been carried out worldwide especially within the marine environments. The release of oil-derived compounds in the sea from anthropogenic sources both as effluents or accidental spill is perceived as a major environmental concern. An approach based on a combination of biomarkers and the distribution of some classes of environmentally relevant pollutants was used to investigate the occurrence of a stress syndrome in mussels (Mytilus galloprovincialis) collected at three gas platforms placed in two distinct oceanographic districts within the Adriatic Sea. Biological responses were integrated by a ranking algorithm which demonstrated both a range of biological effects reflecting exposure gradients and a temporal related trend in the investigated responses. The overall results demonstrate a moderate to absent pollution from studied gas platforms with low but remarkable biological disturbance in sentinel organisms. PMID:25724089

  18. How unclogging a sink can be lethal: case report of an accidental methyl bromide poisoning leading to a multiple organ failure.

    PubMed

    Lecailtel, Sylvain; Broucqsault-Dedrie, Céline; Vanbaelinghem, Clément; Nyunga, Martine; Colling, Delphine; Herbecq, Patrick

    2015-01-01

    Methyl bromide (CH3Br) is a colorless and odorless volatile gas, used as an insecticide, fire extinguisher, fumigant, and refrigerant. Although forbidden since 1987 for domestic use, it is still used in industry, for example, to fumigate agricultural fields which are for importation in the United States. Here is the case of a 74-year-old man who was accidentally exposed to methyl bromide after using an old fire extinguisher. Even though he finally survived, he developed a severe multiple organ failure and spent 2 months in intensive care unit. We present in this report all the difficulties we had to diagnose this unusual poisoning. PMID:27408727

  19. Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Relesed to the Atmosphere from Lawrence Livermore National Laboratory (LLNL) Part 1. Description of Tritium Dose Model (DCART) for Chronic Releases from LLNL

    SciTech Connect

    Peterson, S

    2004-06-30

    DCART (Doses from Chronic Atmospheric Releases of Tritium) is a spreadsheet model developed at Lawrence Livermore National Laboratory (LLNL) that calculates doses from inhalation of tritiated hydrogen gas (HT), inhalation and skin absorption of tritiated water (HTO), and ingestion of HTO and organically bound tritium (OBT) to adult, child (age 10), and infant (age 6 months to 1 year) from routine atmospheric releases of HT and HTO. DCART is a deterministic model that, when coupled to the risk assessment software Crystal Ball{reg_sign}, predicts doses with a 95th percentile confidence interval. The equations used by DCART are described and all distributions on parameter values are presented. DCART has been tested against the results of other models and several sets of observations in the Tritium Working Group of the International Atomic Energy Agency's Biosphere Modeling and Assessment Programme. The version of DCART described here has been modified to include parameter values and distributions specific to conditions at LLNL. In future work, DCART will be used to reconstruct dose to the hypothetical maximally exposed individual from annual routine releases of HTO and HT from all LLNL facilities and from the Sandia National Laboratory's Tritium Research Laboratory over the last fifty years.

  20. Integrated Farm System Model Version 4.1 and Dairy Gas Emissions Model Version 3.1 software release and distribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal facilities are significant contributors of gaseous emissions including ammonia (NH3) and nitrous oxide (N2O). Previous versions of the Integrated Farm System Model (IFSM version 4.0) and Dairy Gas Emissions Model (DairyGEM version 3.0), two whole-farm simulation models developed by USDA-ARS, ...