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Sample records for laboratory low-activity aqueous

  1. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    SciTech Connect

    Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.; Crawford, Charles L.; Wilmarth, William R.

    2014-01-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream, LAW Off-Gas Condensate, from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of canistered glass waste forms. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to be within acceptable concentration ranges in the LAW glass. Diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the impact of potential future disposition of this stream in the Hanford tank farms, and investigates auxiliary evaporation to enable another disposition path. Unless an auxiliary evaporator is used, returning the stream to the tank farms would require evaporation in the 242-A evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter

  2. Laboratory optimization tests of technetium decontamination of Hanford Waste Treatment Plant low activity waste melter off-gas condensate simulant

    SciTech Connect

    Taylor-Pashow, Kathryn M.L.; McCabe, Daniel J.

    2015-11-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable simplified operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  3. Near-field performance assessment for a low-activity waste glass disposal system: laboratory testing to modeling results

    NASA Astrophysics Data System (ADS)

    McGrail, B. P.; Bacon, D. H.; Icenhower, J. P.; Mann, F. M.; Puigh, R. J.; Schaef, H. T.; Mattigod, S. V.

    2001-09-01

    Reactive chemical transport simulations of glass corrosion and radionuclide release from a low-activity waste (LAW) disposal system were conducted out to times in excess of 20 000 yr with the subsurface transport over reactive multiphases (STORM) code. Time and spatial dependence of glass corrosion rate, secondary phase formation, pH, and radionuclide concentration were evaluated. The results show low release rates overall for the LAW glasses such that performance objectives for the site will be met by a factor of 20 or more. Parameterization of the computer model was accomplished by combining direct laboratory measurements, literature data (principally thermodynamic data), and parameter estimation methods.

  4. Aqueous Nitrate Recovery Line at Los Alamos National Laboratory

    SciTech Connect

    Finstad, Casey Charles

    2016-06-15

    This powerpoint is part of the ADPSM Plutonium Engineering Lecture Series, which is an opportunity for new hires at LANL to get an overview of work done at TA55. It goes into detail about the aqueous nitrate recovery line at Los Alamos National Laboratory.

  5. Laboratory study of soil flushing by aqueous solutions

    SciTech Connect

    Park, J.; O`Neill, M.W.; Symons, J.M.

    1998-10-01

    This paper explores the removal of organics from soils in a simulated in-situ environment using aqueous solution extraction. A laboratory investigation is described in which organic compounds representative of the major groups of organic contaminants were adsorbed in low concentrations onto slightly organic, loamy soil, and various aqueous solutions were permeated through the soil under controlled hydraulic gradients and effective stress conditions, simulating the in-situ extraction process. The effectiveness of the extraction process was evaluated by periodically measuring the concentration of the contaminants in the permeameter effluent. Simple contact shaking tests were also performed and compared with the results of the permeation tests to ascertain whether contact shaking tests can be used as an index to the effectiveness of permeation testing. The results may be applicable to injection and extraction wells, in which the solution extract is pumped to a location on the ground surface for treatment.

  6. Laboratory Scoping Tests Of Decontamination Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    SciTech Connect

    Taylor-Pashow, Kathryn M.; Nash, Charles A.; Crawford, Charles L.; McCabe, Daniel J.; Wilmarth, William R.

    2014-01-21

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task seeks to examine the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  7. LABORATORY OPTIMIZATION TESTS OF TECHNETIUM DECONTAMINATION OF HANFORD WASTE TREATMENT PLANT LOW ACTIVITY WASTE OFF-GAS CONDENSATE SIMULANT

    SciTech Connect

    Taylor-Pashow, K.; Nash, C.; McCabe, D.

    2014-09-29

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  8. Laboratory Optimization Tests of Technetium Decontamination of Hanford Waste Treatment Plant Direct Feed Low Activity Waste Melter Off-Gas Condensate Simulant

    SciTech Connect

    Taylor-Pashow, K.; McCabe, D.

    2015-12-23

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  9. Laboratory Optimization Tests of Decontamination of Cs, Sr, and Actinides from Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    SciTech Connect

    Taylor-Pashow, K.; Nash, C.; McCabe, D.

    2015-01-06

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also substantially decrease the LAW vitrification mission duration and quantity of glass waste.

  10. Laboratory Testing of Bulk Vitrified Low-Activity Waste Forms to Support the 2005 Integrated Disposal Facility Performance Assessment

    SciTech Connect

    Pierce, Eric M.; McGrail, B. Peter; Bagaasen, Larry M.; Rodriguez, Elsa A.; Wellman, Dawn M.; Geiszler, Keith N.; Baum, Steven R.; Reed, Lunde R.; Crum, Jarrod V.; Schaef, Herbert T.

    2006-06-30

    The purpose of this report is to document the results from laboratory testing of the bulk vitri-fied (BV) waste form that was conducted in support of the 2005 integrated disposal facility (IDF) performance assessment (PA). Laboratory testing provides a majority of the key input data re-quired to assess the long-term performance of the BV waste package with the STORM code. Test data from three principal methods, as described by McGrail et al. (2000a; 2003a), are dis-cussed in this testing report including the single-pass flow-through test (SPFT) and product con-sistency test (PCT). Each of these test methods focuses on different aspects of the glass corrosion process. See McGrail et al. (2000a; 2003a) for additional details regarding these test methods and their use in evaluating long-term glass performance. In addition to evaluating the long-term glass performance, this report discusses the results and methods used to provided a recommended best estimate of the soluble fraction of 99Tc that can be leached from the engineer-ing-scale BV waste package. These laboratory tests are part of a continuum of testing that is aimed at improving the performance of the BV waste package.

  11. Laboratory Testing of Bulk Vitrified Low-Activity Waste Forms to Support the 2005 Integrated Disposal Facility Performance Assessment

    SciTech Connect

    Pierce, Eric M.; McGrail, B. Peter; Bagaasen, Larry M.; Rodriguez, Elsa A.; Wellman, Dawn M.; Geiszler, Keith N.; Baum, Steven R.; Reed, Lunde R.; Crum, Jarrod V.; Schaef, Herbert T.

    2005-03-31

    The purpose of this report is to document the results from laboratory testing of the bulk vitri-fied (BV) waste form that was conducted in support of the 2005 integrated disposal facility (IDF) performance assessment (PA). Laboratory testing provides a majority of the key input data re-quired to assess the long-term performance of the BV waste package with the STORM code. Test data from three principal methods, as described by McGrail et al. (2000a; 2003a), are dis-cussed in this testing report including the single-pass flow-through test (SPFT) and product con-sistency test (PCT). Each of these test methods focuses on different aspects of the glass corrosion process. See McGrail et al. (2000a; 2003a) for additional details regarding these test methods and their use in evaluating long-term glass performance. In addition to evaluating the long-term glass performance, this report discusses the results and methods used to provided a recommended best estimate of the soluble fraction of 99Tc that can be leached from the engineer-ing-scale BV waste package. These laboratory tests are part of a continuum of testing that is aimed at improving the performance of the BV waste package.

  12. Laboratory Testing of Bulk Vitrified Low-Activity Waste Forms to Support the 2005 Integrated Disposal Facility Performance Assessment. Erratum

    SciTech Connect

    Smith, Gary L.

    2016-09-06

    This report refers to or contains Kg values for glasses LAWA44, LAWB45 and LAWC22 affected by calculations errors as identified by Papathanassiu et al. (2011). The corrected Kg values are reported in an erratum included in the revised version of the original report. The revised report can be referenced as follows: Pierce E. M. et al. (2004) Waste Form Release Data Package for the 2005 Integrated Disposal Facility Performance Assessment. PNNL-14805 Rev. 0 Erratum. Pacific Northwest National Laboratory, Richland, WA, USA.

  13. An Alternative Approach for Preparing and Standardizing Some Common Aqueous Reagents Used in an Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Melaku, Samuel; Dabke, Rajeev B.

    2014-01-01

    A guide for instructors and laboratory assistants to prepare some common aqueous reagents used in an undergraduate laboratory is presented. Dilute reagents consisting of H[superscript +](aq), I[subscript 3][superscript-](aq), Ce[superscript 4+](aq), and Ag[superscript+](aq) were prepared by electrolytic oxidation of respective precursors.…

  14. An Alternative Approach for Preparing and Standardizing Some Common Aqueous Reagents Used in an Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Melaku, Samuel; Dabke, Rajeev B.

    2014-01-01

    A guide for instructors and laboratory assistants to prepare some common aqueous reagents used in an undergraduate laboratory is presented. Dilute reagents consisting of H[superscript +](aq), I[subscript 3][superscript-](aq), Ce[superscript 4+](aq), and Ag[superscript+](aq) were prepared by electrolytic oxidation of respective precursors.…

  15. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    SciTech Connect

    Shott, Gregory J.

    2015-06-01

    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

  16. Low activation ferritic alloys

    DOEpatents

    Gelles, D.S.; Ghoniem, N.M.; Powell, R.W.

    1985-02-07

    Low activation ferritic alloys, specifically bainitic and martensitic stainless steels, are described for use in the production of structural components for nuclear fusion reactors. They are designed specifically to achieve low activation characteristics suitable for efficient waste disposal. The alloys essentially exclude molybdenum, nickel, nitrogen and niobium. Strength is achieved by substituting vanadium, tungsten, and/or tantalum in place of the usual molybdenum content in such alloys.

  17. Low activation ferritic alloys

    DOEpatents

    Gelles, David S.; Ghoniem, Nasr M.; Powell, Roger W.

    1986-01-01

    Low activation ferritic alloys, specifically bainitic and martensitic stainless steels, are described for use in the production of structural components for nuclear fusion reactors. They are designed specifically to achieve low activation characteristics suitable for efficient waste disposal. The alloys essentially exclude molybdenum, nickel, nitrogen and niobium. Strength is achieved by substituting vanadium, tungsten, and/or tantalum in place of the usual molybdenum content in such alloys.

  18. Laboratory evidence of organic peroxide and peroxyhemiacetal formation in the aqueous phase and implications for aqueous OH

    NASA Astrophysics Data System (ADS)

    Lim, Y. B.; Turpin, B. J.

    2015-11-01

    Aqueous chemistry in atmospheric waters (e.g., cloud droplets or wet aerosols) is considered a potentially important atmospheric pathway to produce secondary organic aerosol (SOAaq). Water-soluble organic compounds with small carbon numbers (C2-C3) are precursors for SOAaq; products include organic acids, organic sulfates, and high-molecular-weight compounds/oligomers. Fenton reactions and the uptake of gas-phase OH radicals are considered to be the major oxidant sources for aqueous organic chemistry. However, the sources and availability of oxidants in atmospheric waters are not well understood. The degree to which OH is produced in the aqueous phase affects the balance of radical and non-radical aqueous chemistry, the properties of the resulting aerosol, and likely its atmospheric behavior. This paper demonstrates organic peroxide formation during aqueous photooxidation of methylglyoxal using ultra-high-resolution Fourier transform ion cyclotron resonance electrospray ionization mass spectrometry (FTICR-MS). Organic peroxides are known to form through gas-phase oxidation of volatile organic compounds. They contribute secondary organic aerosol (SOA) formation directly by forming peroxyhemiacetals and epoxides (i.e., IEPOX), and indirectly by enhancing gas-phase oxidation through OH recycling. We provide simulation results of organic peroxide/peroxyhemiacetal formation in clouds and wet aerosols and discuss organic peroxides as a source of condensed-phase OH radicals and as a contributor to aqueous SOA.

  19. The Mars Chemical Analysis Laboratory (MCAL) for in-situ analysis of martian aqueous geochemistry

    NASA Astrophysics Data System (ADS)

    Kounaves, S. P.; Bauer, J.; McElhoney, K. M.

    2013-09-01

    The 2007 Phoenix Mars Lander [1] included four Wet Chemistry Laboratory (WCL) units [2] for performing the first wet chemical analysis of soil on another planet. Each WCL (Figure 1) consisted of electrochemical sensors for analyzing the aqueous geochemical properties of the soil. These included sensors for Ca2+, Mg2+, K+, Na+, NH4 +, Cl-, Br-, I-, NO3 -, pH, and SO4 =; electrodes for measuring electrical conductivity; determining redox potential (Eh), for independent determination of halides, and for identifying redox couples. Three ~1 cm3 soil samples were successfully added to 25mL of water and analyzed. The soil/water mixture had a pH of 7.7(±0.3), conductivity of 1.4(±0.5) mS/cm, with [Ca2+] = 0.5(±0.5) mM, [Mg2+] = 2.9(±1.5) mM, [Na+] = 1.4(±0.6) mM, soluble sulfate SO4 2- = 5.9 (±1.5) mM, [K+] = 0.36(±0.3) mM, and an Eh of 253 (±6) mV. The most unexpected finding was perchlorate (ClO4-), with an average concentration 2.5 (±1) mM [3-6]. Here we describe a heritage-based next generation Mars wet chemistry laboratory for an upcoming mission that, in addition to analyses performed by the Phoenix lander WCL [2-6], extends the capability to several dozen or more soil samples without increasing the demand on spacecraft resources, and extends the quantitative chemical aspects of the analyses to provide for better understanding of the aqueous geochemistry and toxicity of the martian soil.

  20. Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria

    SciTech Connect

    Dougal, R.A.

    1993-08-01

    High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam irradiation were both lethal to the bacteria studied at irradiation levels far lower than were necessary to remove organic contaminants.

  1. Laboratory and Field Age of Aqueous Grape Juice Bait and Capture of Zaprionus indianus (Diptera: Drosophilidae).

    PubMed

    Epsky, Nancy D; Gill, Micah A

    2017-06-01

    Volatile chemicals produced by actively fermenting aqueous grape juice bait have been found to be highly attractive to the African fig fly, Zaprionus indianus Gupta. This is a highly dynamic system and time period of fermentation is an important factor in bait efficacy. A series of field tests were conducted that evaluated effects of laboratory versus field fermentation and sampling period (days after placement [DAP]) on bait effectiveness as the first step in identifying the chemicals responsible for attraction. Tests of traps with bait that had been aged in the laboratory for 0, 3, 6, and 9 d and then sampled 3 DAP found higher capture in traps with 0- and 3-d-old baits than in traps with 6- or 9-d-old baits. To further define the time period that produced the most attractive baits, a subsequent test evaluated baits aged for 0, 2, 4, and 6 d in the laboratory and sampled after 1-4 DAP, with traps sampled and bait discarded at the end of each DAP period. The highest capture was in traps with 4-d-old bait sampled 1 DAP, with the second best capture in traps with 0-d-old bait sampled 3 DAP. However, there tended to be fewer flies as DAP increased, indicating potential loss of identifiable flies owing to decomposition in the actively fermenting solutions. When traps were sampled and bait recycled daily, the highest capture was in 2- and 4-d-old baits sampled 1 DAP and in 0-d-old baits sampled 2-4 DAP. Similar patterns were observed for capture of nontarget drosophilids. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

  2. Laboratory study of non-aqueous phase liquid and water co-boiling during thermal treatment

    NASA Astrophysics Data System (ADS)

    Zhao, C.; Mumford, K. G.; Kueper, B. H.

    2014-08-01

    In situ thermal treatment technologies, such as electrical resistance heating and thermal conductive heating, use subsurface temperature measurements in addition to the analysis of soil and groundwater samples to monitor remediation performance. One potential indication of non-aqueous phase liquid (NAPL) removal is an increase in temperature following observations of a co-boiling plateau, during which subsurface temperatures remain constant as NAPL and water co-boil. However, observed co-boiling temperatures can be affected by the composition of the NAPL and the proximity of the NAPL to the temperature measurement location. Results of laboratory heating experiments using single-component and multi-component NAPLs showed that local-scale temperature measurements can be mistakenly interpreted as an indication of the end of NAPL-water co-boiling, and that significant NAPL saturations (1% to 9%) remain despite observed increases in temperature. Furthermore, co-boiling of multi-component NAPL results in gradually increasing temperature, rather than a co-boiling plateau. Measurements of gas production can serve as a complementary metric for assessing NAPL removal by providing a larger-scale measurement integrated over multiple smaller-scale NAPL locations. Measurements of the composition of the NAPL condensate can provide ISTT operators with information regarding the progress of NAPL removal for multi-component sources.

  3. Partitioning of radiostrontium in marine aqueous suspensions: laboratory experiments and modeling studies.

    PubMed

    Benkdad, A; Laissaoui, A; El Bari, H; Benmansour, M; Ibnmajah, M

    2008-04-01

    Quantitative information on the adsorption/desorption of radionuclides by suspended loads is important in the study of their environmental behavior. In this paper, controlled laboratory experiments were directed at studying the kinetic transfer and final distribution of radiostrontium in aqueous suspensions using 85Sr as tracer. The results showed that the uptake of 85Sr in seawater can be properly described by one reversible-reaction model. However, in the absence of competitive cations, it has been shown that two reactions of different characteristic times are unambiguously involved in the kinetic evolution of adsorption. Thus, a modeling approach consisting of three-box model has been applied. The model predicts in a satisfactory way the time evolution of activities in the dissolved phase and two sites in the particles. Experimental evidence showed, through comparison among kinetic and distribution coefficients corresponding to different conditions, that Ca2+ affects strongly the rate and extent of Sr uptake by suspended particles. On the other hand, distribution coefficients were found to be sensitive to changes in suspended particulate matter (SPM) concentration, exhibiting a reverse effect with this parameter on the adsorption. In addition, desorption from particles is important showing that Sr can be easily released due to cation-exchange processes.

  4. Laboratory study of non-aqueous phase liquid and water co-boiling during thermal treatment.

    PubMed

    Zhao, C; Mumford, K G; Kueper, B H

    2014-08-01

    In situ thermal treatment technologies, such as electrical resistance heating and thermal conductive heating, use subsurface temperature measurements in addition to the analysis of soil and groundwater samples to monitor remediation performance. One potential indication of non-aqueous phase liquid (NAPL) removal is an increase in temperature following observations of a co-boiling plateau, during which subsurface temperatures remain constant as NAPL and water co-boil. However, observed co-boiling temperatures can be affected by the composition of the NAPL and the proximity of the NAPL to the temperature measurement location. Results of laboratory heating experiments using single-component and multi-component NAPLs showed that local-scale temperature measurements can be mistakenly interpreted as an indication of the end of NAPL-water co-boiling, and that significant NAPL saturations (1% to 9%) remain despite observed increases in temperature. Furthermore, co-boiling of multi-component NAPL results in gradually increasing temperature, rather than a co-boiling plateau. Measurements of gas production can serve as a complementary metric for assessing NAPL removal by providing a larger-scale measurement integrated over multiple smaller-scale NAPL locations. Measurements of the composition of the NAPL condensate can provide ISTT operators with information regarding the progress of NAPL removal for multi-component sources.

  5. Laboratory studies of aqueous-phase oxidation of polyols in submicron particles

    NASA Astrophysics Data System (ADS)

    Daumit, K. E.; Carrasquillo, A. J.; Hunter, J. F.; Kroll, J. H.

    2013-12-01

    Aqueous-phase oxidation has received recent attention as a potential pathway for the formation of highly oxidized organic aerosol. However most aqueous oxidation studies are performed in bulk solutions rather than aqueous droplets. Here we describe experiments in which aqueous oxidation is carried out within submicron particles, allowing for gas-particle partitioning of reactants, intermediates, and products. Using Fenton chemistry as a source of hydroxyl radicals, and a high-resolution aerosol mass spectrometer (AMS) for online characterization of particle composition, we find that aqueous oxidation can be quite rapid. The formation of high concentrations of oxalic acid is observed in the particle phase with some loss of carbon to the gas phase, indicating the formation of volatile products. We see a rapid degradation of condensed-phase oxidation products upon exposure to ultraviolet lights (centered at 350 nm) suggesting that these products may exist as iron(III)-oxalate complexes. Similar results are also seen when oxidation is carried out in bulk solution (with AMS analysis of the atomized solution); however in some cases the mass loss is less than is observed for submicron particles, likely due to differences in partitioning of early-generation products. Such products can partition out of the aqueous phase at the low liquid water contents in the chamber but remain in solution for further aqueous processing in bulk oxidation experiments. This work suggests that the product distributions from oxidation in aqueous aerosol may be substantially different than those in bulk oxidation, pointing to the need to carry out aqueous oxidation studies under atmospherically relevant partitioning conditions (with liquid water contents mimicking those of cloud droplets or wet aerosol).

  6. Cellular and aqueous microcystin-LR following laboratory exposures of Microcystis aeruginosa to copper algaecides.

    PubMed

    Iwinski, Kyla J; Calomeni, Alyssa J; Geer, Tyler D; Rodgers, John H

    2016-03-01

    Microcystin release from algal cells influences use of copper-algaecides in water resources. Accurate data regarding relationships between copper-algaecide exposures and responses of microcystin-producing algae are needed to make informed management decisions. Responses of Microcystis aeruginosa were measured in terms of cellular microcystin-LR (MC-LR), aqueous MC-LR, and chlorophyll-a following exposure to CuSO4 and copper-ethanolamine. Comparisons were made between treated and untreated samples, and copper formulations. EC50s and slopes for M. aeruginosa responses to copper exposures were calculated. Algal responses followed a sigmoidal exposure-response relationship, and cellular MC-LR and chlorophyll-a were negatively related to copper concentrations. Aqueous MC-LR increased with copper concentrations, although the increase in aqueous MC-LR was not proportional to decreases in cellular MC-LR and chlorophyll-a. Cellular MC-LR and chlorophyll a declined at a greater rate than aqueous MC-LR increased. Total MC-LR was less than untreated controls following copper exposure. Differences were measured between copper formulations in terms of aqueous and total MC-LR concentrations at concentrations of 0.5 and 1.0 mg Cu L-1. Aqueous and total MC-LR were greater (10-20%) following exposure to CuSO4 compared to copper-ethanolamine one day following exposure. The positive relationship between copper concentration and aqueous MC-LR at 0.07-1.0 mg Cu L-1 demonstrates that lower copper concentrations were as effective as higher concentrations in controlling M. aeruginosa while decreasing the total amount of MC-LR, and minimizing the proportion of MC-LR released to the aqueous-phase. Results serve to support more accurate risk evaluations of MC-LR concentrations when M. aeruginosa is exposed to copper-algaecides and when it is untreated.

  7. Organic peroxide and OH formation in aerosol and cloud water: laboratory evidence for this aqueous chemistry

    NASA Astrophysics Data System (ADS)

    Lim, Y. B.; Turpin, B. J.

    2015-06-01

    Aqueous chemistry in atmospheric waters (e.g., cloud droplets or wet aerosols) is well accepted as an atmospheric pathway to produce secondary organic aerosol (SOAaq). Water-soluble organic compounds with small carbon numbers (C2-C3) are precursors for SOAaq and products include organic acids, organic sulfates, and high molecular weight compounds/oligomers. Fenton reactions and the uptake of gas-phase OH radicals are considered to be the major oxidant sources for aqueous organic chemistry. However, the sources and availability of oxidants in atmospheric waters are not well understood. The degree to which OH is produced in the aqueous phase affects the balance of radical and non-radical aqueous chemistry, the properties of the resulting aerosol, and likely its atmospheric behavior. This paper demonstrates organic peroxide formation during aqueous photooxidation of methylglyoxal using ultra high resolution Fourier Transform Ion Cyclotron Resonance electrospray ionization mass spectrometry (FTICR-MS). Organic peroxides are known to form through gas-phase oxidation of volatile organic compounds. They contribute secondary organic aerosol (SOA) formation directly by forming peroxyhemiacetals, and epoxides, and indirectly by enhancing gas-phase oxidation through OH recycling. We provide simulation results of organic peroxide/peroxyhemiacetal formation in clouds and wet aerosols and discuss organic peroxides as a source of condensed-phase OH radicals and as a contributor to aqueous SOA.

  8. Secondary organic aerosol production from aqueous photooxidation of glycolaldehyde: Laboratory experiments

    NASA Astrophysics Data System (ADS)

    Perri, Mark J.; Seitzinger, Sybil; Turpin, Barbara J.

    Organic particulate matter (PM) formed in the atmosphere (secondary organic aerosol; SOA) is a substantial yet poorly understood contributor to atmospheric PM. Aqueous photooxidation in clouds, fogs and aerosols is a newly recognized SOA formation pathway. This study investigates the potential for aqueous glycolaldehyde oxidation to produce low volatility products that contribute SOA mass. To our knowledge, this is the first confirmation that aqueous oxidation of glycolaldehyde via the hydroxyl radical forms glyoxal and glycolic acid, as previously assumed. Subsequent reactions form formic acid, glyoxylic acid, and oxalic acid as expected. Unexpected products include malonic acid, succinic acid, and higher molecular weight compounds, including oligomers. Due to (1) the large source strength of glycolaldehyde from precursors such as isoprene and ethene, (2) its water solubility, and (3) the aqueous formation of low volatility products (organic acids and oligomers), we predict that aqueous photooxidation of glycolaldehyde and other aldehydes in cloud, fog, and aerosol water is an important source of SOA and that incorporation of this SOA formation pathway in chemical transport models will help explain the current under-prediction of organic PM concentrations.

  9. Aqueous geochemistry of low molecular weight hydrocarbons at elevated temperatures and pressures: constraints from mineral buffered laboratory experiments

    NASA Astrophysics Data System (ADS)

    Seewald, Jeffrey S.

    2001-05-01

    Organic matter, water, and minerals coexist at elevated temperatures and pressures in sedimentary basins and participate in a wide range of geochemical processes that includes the generation of oil and natural gas. A series of laboratory experiments were conducted at 300 to 350°C and 350 bars to examine chemical interactions involving low molecular weight aqueous hydrocarbons with water and Fe-bearing minerals under hydrothermal conditions. Mineral buffers composed of hematite-magnetite-pyrite, hematite-magnetite, and pyrite-pyrrhotite-magnetite were added to each experiment to fix the redox state of the fluid and the activity of reduced sulfur species. During each experiment the chemical system was externally modified by addition of ethene, ethane, propene, 1-butene, or n-heptane, and variations in the abundance of aqueous organic species were monitored as a function of time and temperature. Results of the experiments indicate that decomposition of aqueous n-alkanes proceeds through a series of oxidation and hydration reactions that sequentially produce alkenes, alcohols, ketones, and organic acids as reaction intermediaries. Organic acids subsequently undergo decarboxylation and/or oxidation reactions to form carbon dioxide and shorter chain saturated hydrocarbons. This alteration assemblage is compositionally distinct from that produced by thermal cracking under anhydrous conditions, indicating that the presence of water and minerals provide alternative reaction pathways for the decomposition of hydrocarbons. The rate of hydrocarbon oxidation decreases substantially under reducing conditions and in the absence of catalytically active aqueous sulfur species. These results represent compelling evidence that the stability of aqueous hydrocarbons at elevated temperatures in natural environments is not a simple function of time and temperature alone. Under the appropriate geochemical conditions, stepwise oxidation represents a mechanism for the decomposition of low

  10. Photochemistry of iron(III)-carboxylato complexes in aqueous atmospheric particles - Laboratory experiments and modeling studies

    NASA Astrophysics Data System (ADS)

    Weller, C.; Tilgner, A.; Herrmann, H.

    2010-12-01

    Iron is always present in the atmosphere in concentrations from ~10-9 M (clouds, rain) up to ~10-3 M (fog, particles). Sources are mainly mineral dust emissions. Iron complexes are very good absorbers in the UV-VIS actinic region and therefore photo-chemically reactive. Iron complex photolysis leads to radical production and can initiate radical chain reactions, which is related to the oxidizing capacity of the atmosphere. These radical chain reactions are involved in the decomposition and transformation of a variety of chemical compounds in cloud droplets and deliquescent particles. Additionally, the photochemical reaction itself can be a degradation pathway for organic compounds with the ability to bind iron. Iron-complexes of atmospherically relevant coordination compounds like oxalate, malonate, succinate, glutarate, tartronate, gluconate, pyruvate and glyoxalate have been investigated in laboratory experiments. Iron speciation depends on the iron-ligand ratio and the pH. The most suitable experimental conditions were calculated with a speciation program (Visual Minteq). The solutions were prepared accordingly and transferred to a 1 cm quartz cuvette and flash-photolyzed with an excimer laser at wavelengths 308 or 351 nm. Photochemically produced Fe2+ has been measured by spectrometry at 510 nm as Fe(phenantroline)32+. Fe2+ overall effective quantum yields have been calculated with the concentration of photochemically produced Fe2+ and the measured energy of the excimer laser pulse. The laser pulse energy was measured with a pyroelectric sensor. For some iron-carboxylate systems the experimental parameters like the oxygen content of the solution, the initial Iron concentration and the incident laser energy were systematically altered to observe an effect on the overall quantum yield. The dependence of some quantum yields on these parameters allows in some cases an interpretation of the underlying photochemical reaction mechanism. Quantum yields of malonate

  11. Low-Activity Radioactive Wastes

    EPA Pesticide Factsheets

    In 2003 EPA published an Advance Notice of Proposed Rulemaking (ANPR) to collect public comment on alternatives for disposal of waste containing low concentrations of radioactive material ('low-activity' waste).

  12. First inter-laboratory comparison exercise for the determination of anticancer drugs in aqueous samples.

    PubMed

    Heath, Ester; Česen, Marjeta; Negreira, Noelia; de Alda, Miren Lopez; Ferrando-Climent, Laura; Blahova, Lucie; Nguyen, Tung Viet; Adahchour, Mohamed; Ruebel, Achim; Llewellyn, Neville; Ščančar, Janez; Novaković, Srdjan; Mislej, Vesna; Stražar, Marjeta; Barceló, Damià; Kosjek, Tina

    2016-08-01

    The results of an inter-laboratory comparison exercise to determine cytostatic anticancer drug residues in surface water, hospital wastewater and wastewater treatment plant effluent are reported. To obtain a critical number of participants, an invitation was sent out to potential laboratories identified to have the necessary knowledge and instrumentation. Nine laboratories worldwide confirmed their participation in the exercise. The compounds selected (based on the extent of use and laboratories capabilities) included cyclophosphamide, ifosfamide, 5-fluorouracil, gemcitabine, etoposide, methotrexate and cisplatinum. Samples of spiked waste (hospital and wastewater treatment plant effluent) and surface water, and additional non-spiked hospital wastewater, were prepared by the organising laboratory (Jožef Stefan Institute) and sent out to each participant partner for analysis. All analytical methods included solid phase extraction (SPE) and the use of surrogate/internal standards for quantification. Chemical analysis was performed using either liquid or gas chromatography mass (MS) or tandem mass (MS/MS) spectrometry. Cisplatinum was determined using inductively coupled plasma mass spectrometry (ICP-MS). A required minimum contribution of five laboratories meant that only cyclophosphamide, ifosfamide, methotrexate and etoposide could be included in the statistical evaluation. z-score and Q test revealed 3 and 4 outliers using classical and robust approach, respectively. The smallest absolute differences between the spiked values and the measured values were observed in the surface water matrix. The highest within-laboratory repeatability was observed for methotrexate in all three matrices (CV ≤ 12 %). Overall, inter-laboratory reproducibility was poor for all compounds and matrices (CV 27-143 %) with the only exception being methotrexate measured in the spiked hospital wastewater (CV = 8 %). Random and total errors were identified by means of Youden

  13. Aqueous dissolution of laboratory and field samples from the in-situ vitrification process

    SciTech Connect

    McGrail, B.P. ); Bates, S.O. )

    1991-08-01

    In-situ vitrification (ISV) is being evaluated in several countries as a remediation technology for immobilizing both hazardous and radioactive buried wastes. A combination of laboratory data and modeling results are presented that establishes the scientific basis for predicting the long-term stability of an ISV glass in the environment. Laboratory experiments included tests with ISV samples obtained from pilot- and intermediate-scale field tests, a nuclear waste glass, and a natural obsidian. 8 refs.

  14. Experimental studies in high temperature aqueous chemistry at Oak Ridge National Laboratory

    SciTech Connect

    Mesmer, R.E.; Palmer, D.A.; Simonson, J.M.; Holmes, H.F.; Ho, P.C.; Wesolowski, D.J.; Gruszkiewicz, M.S.

    1996-01-01

    Experimental research is conducted and models developed in a long- standing program at Oak Ridge on aqueous chemistry at high temperatures of broad classes of electrolytes emphasizing thermodynamics of reaction equilibria and excess thermodynamic properties of electrolytes. Experimental methods, their capabilities, data analysis, and results are summarized. Relevance of the work to problems in power plants, natural and industrial processes as well as basic solution chemistry and geochemistry are given. Progress in potentiometry, electrical conductivity, flow calorimetry, and isopiestic research is described. Future in this field demands greater precision in measurements and significant gains in our understanding of the solvation phenomena especially in the vicinity and beyond the critical point for water. The communities who do research on scattering, spectroscopy, and computer simulations can help guide these efforts through studies at extreme conditions.

  15. A Green Multicomponent Reaction for the Organic Chemistry Laboratory: The Aqueous Passerini Reaction

    ERIC Educational Resources Information Center

    Hooper, Matthew M.; DeBoef, Brenton

    2009-01-01

    Water is the ideal green solvent for organic reactions. However, most organic molecules are insoluble in it. Herein, we report a laboratory module that takes advantage of this property. The Passerini reaction, a three-component coupling involving an isocyanide, aldehyde, and carboxylic acid, typically requires [similar to] 24 h reaction times in…

  16. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 2

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  17. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 3

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  18. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING LIGHT TRANSMISSION VISUALIZATION METHOD

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  19. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 1

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  20. A Green Multicomponent Reaction for the Organic Chemistry Laboratory: The Aqueous Passerini Reaction

    ERIC Educational Resources Information Center

    Hooper, Matthew M.; DeBoef, Brenton

    2009-01-01

    Water is the ideal green solvent for organic reactions. However, most organic molecules are insoluble in it. Herein, we report a laboratory module that takes advantage of this property. The Passerini reaction, a three-component coupling involving an isocyanide, aldehyde, and carboxylic acid, typically requires [similar to] 24 h reaction times in…

  1. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING LIGHT TRANSMISSION VISUALIZATION METHOD

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  2. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 1

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  3. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 3

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  4. THE QUANTIFICATION OF AQUEOUS TRACERS IN LABORATORY AQUIFER MODELS USING A LIGHT TRANSMISSION VISUALIZATION METHOD - 2

    EPA Science Inventory

    The quantification of solute concentrations in laboratory aquifer models has been largely limited to the use of sampling ports, from which samples are collected for external analysis. One of the drawbacks to this method is that the act of sampling may disturb plume dynamics and ...

  5. Photochemical Activity of Aldrin and Dieldrin in Liquid and Frozen Aqueous Systems: Field and Laboratory Studies

    NASA Astrophysics Data System (ADS)

    Bausch, A. R.; Rowland, G. A.; Grannas, A. M.

    2008-12-01

    The phenomenon of global distillation generates significant accumulation of volatile, anthropogenic persistent organic pollutants (POPs) in polar regions. Bioaccumulation presents serious concerns for human health within Arctic subsistence communities. In the recent past, the photochemical processes of POPs have been observed in the laboratory. Despite some established knowledge regarding photochemical processes in reactive frozen media, little published literature exists regarding the chemical transformations and fate of POPs in the Arctic. Here, we consider the photochemical transformations of aldrin and dieldrin, two structurally similar organochlorine pollutants whose presence has been confirmed in the Arctic. Their photochemical transformation, resulting from ultraviolet exposure, was investigated by both field studies in Barrow, AK and controlled laboratory experiments. Pollutant degradation and photoproduct formation were monitored by GC-ECD analysis. Based on kinetic studies of liquid and frozen samples and identification of photoproducts, we will propose potential reaction mechanisms for the transformations of aldrin and dieldrin. Further implications for environmental processes will be discussed.

  6. Laboratory kinetic and mechanistic studies on the OH-initiated oxidation of acetone in aqueous solution.

    PubMed

    Schaefer, Thomas; Schindelka, Janine; Hoffmann, Dirk; Herrmann, Hartmut

    2012-06-21

    The OH-initiated oxidation of acetone in aqueous solution is investigated because of its potential implications in atmospheric chemistry. The UV-spectrum of the transient acetonylperoxy radical was measured. Two characteristic absorption bands of the acetonylperoxy radical spectrum are found in the 220-400 nm wavelength region. The rate constant for the recombination reaction of the acetonylperoxy radical was determined as a function of temperature for the first time in aqueous solution with k(rec,298 K) = (7.3 ± 1.3) × 10(8) M(-1) s(-1), E(A) = 4.5 ± 3.3 kJ mol(-1), and A = (4.7 ± 2.7) × 10(9) M(-1) s(-1). Furthermore, kinetic investigations of the OH-initiated oxidation of methylglyoxal and pyruvic acid were performed with the following results: for methylglyoxal, k(second) = (6.2 ± 0.2) × 10(8) M(-1) s(-1), E(A) = 12 ± 2 kJ mol(-1), and A = (7.8 ± 0.2) × 10(9) M(-1) s(-1); for pyruvic acid (pH = 0), k(second) = (3.2 ± 0.6) × 10(8) M(-1) s(-1), E(A) = 15 ± 5 kJ mol(-1), and A = (1.1 ± 0.1) × 10(11) M(-1) s(-1); for pyruvate (pH = 6), k(second) = (7.1 ± 2.4) × 10(8) M(-1) s(-1), E(A) = 25 ± 19 kJ mol(-1), and A = (1.5 ± 0.4) × 10(13) M(-1) s(-1). Quantitative product studies were done as a function of the number of laser photolysis pulses for acetone and its oxidation products methylglyoxal, hydroxyacetone, pyruvic acid, acetic acid, and oxalic acid. After the recombination reaction of acetonylperoxy radicals, there are two possible decomposition reactions where the primary products methylglyoxal and hydroxyacetone are formed. From product analysis after a single photolysis laser shot, the ratio of the main product-forming reactions was determined as (A) 30% and (B) 56% for the methylglyoxal formation via channel A to yield two molecules of methylglyoxal and channel B to yield one molecule of methylglyoxal and one molecule of hydroxyacetone. The remaining product can be ascribed to channel C, the radical-retaining channel forming alkoxy

  7. Laboratory studies on the OH-initiated oxidation of acetone in the aqueous phase

    NASA Astrophysics Data System (ADS)

    Schaefer, T.; Herrmann, H.

    2010-07-01

    Small organic compounds, such as acetone and its oxidation products, are emitted by a variety of natural and anthropogenic sources in the atmosphere. The degradation or transformation of these compounds can occur in the gas phase and in the liquid phase (cloud droplets, fog, rain or hygroscopic particles) of the troposphere. A special role plays the OH radical, which is one of the most reactive radicals in the atmosphere. To study the OH radical reaction towards small organic compounds in the aqueous phase, a thermostated laser photolysis long path absorption set-up was used. The OH radicals were generated directly in the reaction cell by the photolysis of hydrogen peroxide (H2O2) at ? = 248 nm and monitored using the thiocyanate reference system. Furthermore, the objective of this work is to identify and characterize the various transient species formed in the OH radical reaction. In order to characterize the optical properties of the formed transient compounds (e.g. organic peroxy radicals) a laser photolysis long path absorption apparatus coupled with a CCD-camera / grating combination is used. With this technique time resolved spectra (at different delay times after the excimer laser pulse) of the reactants and products can be recorded. Within this contribution organic peroxy radical spectra of the following parent carbonyl compounds (a) acetone, (b) hydroxyacetone and (c) methylglyoxal will be presented, discussed and compared with literature data. The optical characterization of the formed transient compound is necessary to measure rate constants of elementary reaction steps in the degradation process of the small organic compounds. .

  8. Laboratory testing of waste glass aqueous corrosion; effects of experimental parameters

    SciTech Connect

    Ebert, W.L.; Mazer, J.J.

    1993-12-31

    A literature survey has been performed to assess the effects of the temperature, glass surface area/leachate volume ratio, leachant composition, leachant flow rate, and glass composition (actual radioactive vs. simulated glass) used in laboratory tests on the measured glass reaction rate. The effects of these parameters must be accounted for in mechanistic models used to project glass durability over long times. Test parameters can also be utilized to highlight particular processes in laboratory tests. Waste glass corrosion results as water diffusion, ion-exchange, and hydrolysis reactions occur simultaneously to devitrify the glass and release soluble glass components into solution. The rates of these processes are interrelated by the affects of the solution chemistry and glass alteration phases on each process, and the dominant (fastest) process may change as the reaction progresses. Transport of components from the release sites into solution may also affect the observed corrosion rate. The reaction temperature will affect the rate of each process, while other parameters will affect the solution chemistry and which processes are observed during the test. The early stages of corrosion will be observed under test conditions which maintain dilute leachates and the later stages will be observed under conditions that generate more concentrated leachate solutions. Typically, water diffusion and ion-exchange reactions dominate the observed glass corrosion in dilute solutions while hydrolysis reactions dominant in more concentrated solutions. Which process(es) controls the long-term glass corrosion is not fully understood, and the long-term corrosion rate may be either transport- or reaction-limited.

  9. Ligand-Free Suzuki-Miyaura Coupling Reactions Using an Inexpensive Aqueous Palladium Source: A Synthetic and Computational Exercise for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hill, Nicholas J.; Bowman, Matthew D.; Esselman, Brian J.; Byron, Stephen D.; Kreitinger, Jordan; Leadbeater, Nicholas E.

    2014-01-01

    An inexpensive procedure for introducing the Suzuki-Miyaura coupling reaction into a high-enrollment undergraduate organic chemistry laboratory course is described. The procedure employs an aqueous palladium solution as the catalyst and a range of para-substituted aryl bromides and arylboronic acids as substrates. The coupling reactions proceed…

  10. Ligand-Free Suzuki-Miyaura Coupling Reactions Using an Inexpensive Aqueous Palladium Source: A Synthetic and Computational Exercise for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hill, Nicholas J.; Bowman, Matthew D.; Esselman, Brian J.; Byron, Stephen D.; Kreitinger, Jordan; Leadbeater, Nicholas E.

    2014-01-01

    An inexpensive procedure for introducing the Suzuki-Miyaura coupling reaction into a high-enrollment undergraduate organic chemistry laboratory course is described. The procedure employs an aqueous palladium solution as the catalyst and a range of para-substituted aryl bromides and arylboronic acids as substrates. The coupling reactions proceed…

  11. Laboratory assessment of molluscicidal activity of crude aqueous and ethanolic extracts of Dalbergia sissoo plant parts against Biomphalaria pfeifferi.

    PubMed

    Adenusi, Adedotun A; Odaibo, Alexander B

    2008-07-01

    In the continued search for molluscicidal compounds from plants, crude aqueous and ethanolic extracts from different parts of Dalbergia sissoo Roxb. 1832, were evaluated against egg masses and adults of Biomphalaria pfeifferi (Krauss, 1848), the snail intermediate host of Schistosoma mansoni (Sambon, 1907) in Nigeria. Laboratory-bred adult B. pfeifferi and their viable 0-24 h old egg masses were separately exposed to five different concentrations (7.81-2000 mg l(-1)) each, of the crude aqueous and ethanolic extracts of the fruits, leaves, roots and stem bark of D. sissoo, for 24 h. The LC50 and LC90 values of each extract for the target organisms were calculated using probit analysis. Only the ethanolic extracts of the fruits and roots showed significant activities against the adult snails (24 h LC90<100 mg l(-1): 74.33 and 93.93 mg l(-1), respectively) and their egg masses (LC90: 89.29 and 114.29 mg l(-1), respectively) while all other extracts demonstrated weak molluscicidal and ovicidal activities (24 h LC90 > 100 mg l(-1)). There were concentration-dependent behavioural changes in snails exposed to test extracts, while egg mortalities, manifested at the gastrula/exogastrula stage and or the prehatch snail stage of development, were similarly concentration-dependent. The crude ethanolic extracts of D. sissoo fruits and roots exhibited promising molluscicidal activities (LC90 values<100 mg l(-1)) against adult B. pfeifferi with additional toxicities towards its 0-24 h-old egg masses.

  12. Effect of Humic Acid on Migration, Distribution and Remediation of Dense Non-aqueous Phase Liquids: A laboratory investigation

    NASA Astrophysics Data System (ADS)

    Cheng, Z.; Wu, J.; Xu, H.; Gao, Y.

    2014-12-01

    Over the last decades, dense non-aqueous phase liquids (DNAPLs) contamination in the subsurface increases with the rapid development of oil industry and becomes the focus of many studies. The migration, distribution and remediation efficiency of DNAPLs in the subsurface environment are greatly affected by the solution chemistry besides the physical heterogeneities of aquifers. Humic acid (HA), which is ubiquitous in natural environments, is a surface active substance exhibiting solubility enhancement behavior for hydrophobic organic compounds such as DNAPLs. Here we reported a laboratory investigation to study the effects of HA on the infiltration, immobilization and subsequent recovery of DNAPL in porous media. Tetrachloroethylene (PCE) was selected as the representative DNAPL in this study. Two-dimensional (2-D) sandbox experiments were conducted to investigate the effects of different HA concentrations on the transport, distribution of PCE and the remediation of PCE using surfactant (Tween 80) flushing in a saturated porous media system. The surfactant flushing of PCE was performed after the PCE transport and distribution had reached equilibrium. A light transmission visualization method with charge-coupled device (CCD) camera was adopted to visualize PCE distribution and quantify its saturation. In addition, the experiments were also designed to gather data for the validation of multiphase flow models. Effluent samples were collected to determine dissolved PCE concentrations. PCE solubilization and PCE-water interfacial tension were experimentally determined in aqueous solutions of varying HA concentrations. The experimental results showed that the presence of HA can have a dramatic impact on PCE flow and entrapment, and significantly improved the recovery of PCE during surfactant enhanced aquifer remediation (SEAR). The findings are of use for better understanding of the migration and entrapment of DNAPLs and developing of SEAR technology.

  13. Aqueous-phase disappearance of atrazine, metolachlor, and chlorpyrifos in laboratory aquaria and outdoor macrocosms.

    PubMed

    Mazanti, L; Rice, C; Bialek, K; Sparling, D; Stevenson, C; Johnson, W E; Kangas, P; Rheinstein, J

    2003-01-01

    Dissipation processes are described for a combination of commonly used pesticides-atrazine (6-chloro-4-ethylamino-6-isopropylamino- s-triazine), metolachlor (2-chloro- N-[2-ethyl-6-methyl-phenyl]- N-[2-methoxy-1-methylethyl] acetamide), and chlorpyrifos ( O-O diethyl O-[3,5,6-trichloro-2-pyridinyl] phosphorothioate)-in a laboratory and outdoor pond systems. Dosing rates and timing were designed to duplicate those common in the mid-Atlantic Coastal Plain, USA. Treatments ranged from 2 and 2.5 mg/L to 0.2 and 0.25 mg/L respectively for atrazine and metolachlor, and chlorpyrifos was added at 1.0 and 0.1 mg/L in the aquaria and at 0.1 mg/L in the outdoor macrocosms. Chlorpyrifos disappearance was rapid in all of the systems and followed a two-phase sequence. Initial half-lives varied from 0.16 day to 0.38 day and showed similar rates in the aquaria and the outdoor systems. The second phase of the chlorpyrifis loss pattern was slower (18-20 days) in all the treatments except for the low herbicide treatment in the outdoor test, where it was 3.4 days. Compared to the outdoor system, herbicide losses were much slower in the aquaria, e.g., 150 days for atrazine and 55 days for metolachlor, and no appreciable loss of herbicide was apparent in the high-treated aquaria. In the outdoor systems, the half-lives for the low herbicide treatment were 27 days and 12 days, respectively, for atrazine and metolachlor, and 48 and 20 days, respectively for the high herbicide-treated pond. Very low levels of CIAT (6-amino-2-chloro-4-iso-propylamino- s-triazine) and CEAT (2-chloro-4-ethylamino-6-ethylamino- s-triazine), degradation products of atrazine, were observed in the outdoor studies.

  14. Aqueous-phase disappearance of atrazine, metolachlor, and chlorpyrifos in laboratory aquaria and outdoor macrocosms

    USGS Publications Warehouse

    Mazanti, L.; Rice, C.; Bialek, K.; Sparling, D.; Stevenson, C.; Johnson, W.E.; Kangas, P.; Rheinstein, J.

    2003-01-01

    Dissipation processes are described for a combination of commonly used pesticides--atrazine (6-chloro-4--ethylamino-6-isopropylamino-s-triazine), metolachlor (2-chloro-N-[2-ethyl-6-methyl-phenyl]-N-[2-methoxy-l-methylethyl] acetamide), and chlorpyrifos (O-O diethyl O-[3,5,6-trichloro-2-pyridinyl] phosphorothioate)--in a laboratory and outdoor pond systems. Dosing rates and timing were designed to duplicate those common in the mid-Atlantic Coastal Plain, USA. Treatment ranged from 2 and 2.5 mg/L to 0.2 and 0.25 mg/L respectively for atrazine and metolachlor, and chlorpyrifos was added at 1.0 and 0.1 mg/L in the aquaria and at 0.1 mg/L in the outdoor macrocosms. Chlorpyrifos disappearance was rapid in all of the systems and followed a two-phase sequence. Initial half-lives varied from 0.16 da), to 0.38 day and showed similar rates in the aquaria and the outdoor systems. The second phase of the chlorpyrifos loss pattern was slower (18-20 days) in all the treatments except for the low herbicide treatment in the outdoor test, where it was 3.4 days. Compared to the outdoor system, herbicide losses were much slower in the aquaria, e.g., 150 days for atrazine and 55 days for metolachlor, and no appreciable loss of herbicide was apparent in the high-treated aquaria. In the outdoor systems, the half-lives for the low herbicide treatment were 27 days and 12 days, respectively, for atrazine and metolachlor, and 48 and 20 days, respectively for the high herbicide-treated pond. Very low levels of CIAT (6-amino-2-chloro-4-iso-propylamino-s-triazine) and CEAT (2-chloro-4-ethylamino-6-ethylamino-s-triazine), degradation products of atrazine, were observed in the outdoor studies.

  15. Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes

    SciTech Connect

    Jantzen, C. M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A.; Cozzi, A. D.; Herman, C. C.

    2012-10-22

    Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.

  16. Cementitious Wasteforms for Immobilization of Low-Activity Radioactive Wastes

    SciTech Connect

    Wellman, Dawn M.; Bovaird, Chase C.; Parker, Kent E.; Mattigod, Shas V.; Clayton, Libby N.; Powers, Laura; Wood, Marcus I.; Cordova, Elsa A.; Davis, Aaron M.

    2009-10-29

    Solidification of low-activity wastes with cementitious materials is a widely accepted technique that contains and isolates waste from the hydrologic environment. The radionuclides I-129, Se-75, Tc-99, and U-238 are identified as long-term dose contributors. The anionic nature of these radionuclides in aqueous solutions allows them to readily leach into the subsurface environment. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages via mass flow and/or diffusion into the surrounding subsurface environment. Assessing the long-term performance of waste grouts for encasement of radionuclides requires understanding the: 1) speciation and interaction of the radionuclides within the concrete wasteform, 2) diffusion of radionuclide species when contacted with vadose zone porewater or groundwater under environmentally relevant conditions, and 3) long-term durability and weathering of concrete waste forms. An improved understanding of the interactions of long-lived radionuclides in cementitious matrices will improve predictions of the long-term fate of these sequestered contaminants. An integrated laboratory investigation has been conducted including a: 1) multifaceted spectroscopic investigation to interrogate the speciation and interaction of radionuclides within concrete wasteforms, 2) solubility tests to quantify the stability of solid phases identified as radionuclide-controlling phases, 3) quantify the diffusion of radionuclides from concrete wasteforms into surrounding subsurface sediment under realistic moisture contents (4%, 7%, and 15% by weight moisture content), 4) quantify the long-term durability of concrete waste forms as a function environmental parameters relevant to depository conditions, and 5) identify the formation of secondary phases or processes (microcracking) that influence radionuclide retention. Data obtained from this investigation provides valuable information for

  17. Laboratory evaluation of aqueous leaf extract of Tephrosia vogelii against larvae of Aedes albopictus (Diptera: Culicidae) and non-target aquatic organisms.

    PubMed

    Li, Weisheng; Huang, Congling; Wang, Kun; Fu, Jiantao; Cheng, Dongmei; Zhang, Zhixiang

    2015-06-01

    Mosquito control using insecticides has been the most successful intervention known to reduce malaria prevalence or incidence. However, vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. In this research, the leaf aqueous leachate of Tephrosia vogelii was evaluated for its toxicity against larvae of the most invasive mosquito worldwide, Aedes albopictus (Diptera: Culicidae), and toward adults of the water flea, Daphnia magna (Cladocera: Crustacea) and Oreochromis niloticus, two non-target aquatic organisms that share the same ecological niche of A. albopictus. The leaf aqueous leachate of T. vogelii was evaluated against fourth-instar larvae, non-blood fed 3-5 days old laboratory strains of A. albopictus under laboratory condition. In addition, the objective of the present work was to study the environmental safety evaluation for aquatic ecosystem. Mortality was then recorded after 7d exposure. The leaf aqueous leachate of T. vogelii showed high mosquitocidal activity against larvae of A. albopictus, with a LC50=1.18μg/mL. However, it had a remarkable acute toxicity also toward adults of the non-target arthropod D. magna, with a LC50=0.47μg/L and O. niloticus with a LC50=5.31μg/L. The present findings have important implications in the practical control of mosquito larvae in the aquatic ecosystem, as the medicinal plants studied are commonly available in large quantities. The extract could be used in stagnant water bodies for the control of mosquitoes acting as vector for many communicable diseases.

  18. Laboratory studies of humidity-driven phase transitions of perchlorate/chloride mixtures: Relevance to aqueous phases on Mars

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Tolbert, M. A.

    2012-12-01

    Perchlorate salts, known to exist on Mars, can readily absorb water vapor and deliquesce into aqueous solution. We have previously studied pure perchlorate and found that the deliquescence relative humidity (DRH) is <60% regardless of cation, hydration state or temperature (223 to 273 K). We have also shown that efflorescence (recrystallization) of perchlorate solutions is kinetically hindered, allowing supersaturation to occur at RH values below the DRH. In addition to perchlorate, Phoenix instruments found chloride, sulfate, carbonate, magnesium, sodium, potassium and calcium in the Martian regolith. The vertical and spatial distributions of these ions are unknown, but all were present in a single 1 g sample. It is therefore likely that these ions coexist with perchlorate. Many salts likely present in the regolith are less deliquescent than perchlorates, and it is important to understand how these additional species will affect perchlorate deliquescence. Here we study deliquescence (solid to aqueous transition) and efflorescence (aqueous to solid transition) of 3 perchlorate/chloride systems: KClO4/KCl at 253 K and NaClO4/NaCl and Mg(ClO4)2/MgCl2 at 243 and 253 K. A Raman microscope and environmental cell were used to monitor phase transitions of internally mixed perchlorate/chloride particles. The eutonic RH, where an aqueous phase first forms, is 30% RH for Mg(ClO4)2/MgCl2, 38% RH for NaClO4/NaCl and 82% RH for KClO4/KCl mixtures regardless of initial composition. We observed complete deliquescence of all salt mixtures at RH values below the DRH of the least deliquescent pure salt. When humidity is lowered, efflorescence of all solutions occurred below the DRH suggesting supersaturated solutions can exist. The low eutonic RH values of the sodium and magnesium perchlorate/chloride mixtures are significant for Mars, as these humidities can be reached at the Martian surface. It is likely that some salts in the regolith may exist as stable or metastable solutions

  19. High-Precision Laboratory Measurements Supporting Retrieval of Water Vapor, Gaseous Ammonia, and Aqueous Ammonia Clouds with the Juno Microwave Radiometer (MWR)

    NASA Astrophysics Data System (ADS)

    Steffes, Paul G.; Hanley, Thomas R.; Karpowicz, Bryan M.; Devaraj, Kiruthika; Noorizadeh, Sahand; Duong, Danny; Chinsomboon, Garrett; Bellotti, Amadeo; Janssen, Michael A.; Bolton, Scott J.

    2016-08-01

    The NASA Juno mission includes a six-channel microwave radiometer system (MWR) operating in the 1.3-50 cm wavelength range in order to retrieve abundances of ammonia and water vapor from the microwave signature of Jupiter (see Janssen et al. 2016). In order to plan observations and accurately interpret data from such observations, over 6000 laboratory measurements of the microwave absorption properties of gaseous ammonia, water vapor, and aqueous ammonia solution have been conducted under simulated Jovian conditions using new laboratory systems capable of high-precision measurement under the extreme conditions of the deep atmosphere of Jupiter (up to 100 bars pressure and 505 K temperature). This is one of the most extensive laboratory measurement campaigns ever conducted in support of a microwave remote sensing instrument. New, more precise models for the microwave absorption from these constituents have and are being developed from these measurements. Application of these absorption properties to radiative transfer models for the six wavelengths involved will provide a valuable planning tool for observations, and will also make possible accurate retrievals of the abundance of these constituents during and after observations are conducted.

  20. Laboratory evaluation of the aqueous extract of Azadirachta indica (neem) wood chippings on Anopheles gambiae s.s. (Diptera: Culicidae) mosquitoes.

    PubMed

    Howard, Annabel F V; Adongo, Elizabeth A; Hassanali, Ahmed; Omlin, Francois X; Wanjoya, Anthony; Zhou, Guofa; Vulule, John

    2009-01-01

    Azadirachta indica A. Juss (the neem tree), a source of limonoid insect growth regulatory (IGRs), grows well in many places in sub-Saharan Africa. We explored the potential of neem wood and bark chippings in malaria vector control by evaluating their aqueous extracts as a larvicide and growth disruptor of Anopheles gambiae s.s. (Diptera: Culicidae) under laboratory conditions. Immature stages of the mosquito were tested using WHO guidelines. Fifty percent inhibition of adult emergence (IE50) of all larval instars was obtained with <0.4 g of neem chippings in 1 liter of distilled water. For pupae, significant mortality occurred at 5 g/liter. Inhibition of pupation was seen with some larvae staying as LIVs for 9 d before dying. In addition to growth retardation, reduced reaction by larvae to visual and mechanical stimuli observed at higher neem concentrations may make them more susceptible to natural predators. There were no significant differences in the sex ratio of emerged adults or wing length of females compared with the controls. High-performance liquid chromatography of aqueous extracts showed a series of constituents of varying polarity, including the limonoids nimbin and salannin, which were quantified. Azadirachtin was not detected and the observed activities are attributed to other constituents of the chippings. Such larvicides can be particularly effective where larval habitats are relatively large and readily identifiable. Aqueous extracts of neem wood chippings can be produced locally and their use has the potential to be a low-tech component of integrated malaria vector control schemes in sub-Saharan Africa.

  1. Laboratory kinetic and mechanistic studies on the OH-initiated oxidation of acetone in the aqueous phase

    NASA Astrophysics Data System (ADS)

    Schaefer, T.; Schindelka, J.; Herrmann, H.

    2010-12-01

    Small organic compounds, such as acetone and its oxidation products, are released in the atmosphere by numerous natural and anthropogenic sources. The degradation or transformation of these compounds can occur either in the gas phase or in the liquid phase of cloud droplets, fog, rain or hygroscopic particles within the troposphere. The OH radical plays a decisive role as it is one of the most reactive radicals in the atmosphere. To study the OH radical reaction towards small organic compounds in the aqueous phase, a thermostated laser photolysis long path absorption set-up was used. The OH radicals were generated directly in the reaction cell by the photolysis of hydrogen peroxide (H2O2) at λ = 248 nm and monitored using the thiocyanate reference system. Furthermore, the objective of this work is to identify and characterize the various transient species formed in the OH radical reaction and their first stable oxidation products. In order to characterize the optical properties of the formed transient compounds (e.g. organic peroxy radicals) a laser photolysis long path absorption apparatus coupled with a CCD-camera / grating combination is used. With this technique time resolved spectra (at different delay times after the excimer laser pulse) of the reactants and products were recorded. The optical characterization of the formed organic peroxy radicals is needed to investigate temperature dependent rate constants of their recombination reactions. Within this contribution organic peroxy radical spectra and the T-dependent rate constants for the recombination reactions of the carbonyl compounds (a) acetone, (b) hydroxyacetone and (c) methylglyoxal will be presented, discussed and compared with literature data. In addition to clarify the degradation mechanism of acetone in the aqueous solution the product distributions have been studied with different analytical techniques such as HPLC-UV and HPLC-MS after laser flash photolysis. Identified reaction products are

  2. Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

    NASA Astrophysics Data System (ADS)

    Pavuluri, C. M.; Kawamura, K.; Mihalopoulos, N.; Swaminathan, T.

    2015-01-01

    To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA) and biogenic aerosols (BA), for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2) and malonic (C3) and other C8-C12 diacids overwhelmed their production in aqueous aerosols whereas succinic acid (C4) and C5-C7 diacids showed a significant increase (ca. 10 times) during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment, except for ω-oxooctanoic acid (ωC8) that showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids dominates their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8) is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

  3. Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

    NASA Astrophysics Data System (ADS)

    Pavuluri, C. M.; Kawamura, K.; Mihalopoulos, N.; Swaminathan, T.

    2015-07-01

    To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA) and biogenic (BA) aerosols, for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2), malonic (C3) and other C8-C12 diacids overwhelmed their production in aqueous aerosols, whereas succinic acid (C4) and C5-C7 diacids showed a significant increase (ca. 10 times) during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment except for ω-oxooctanoic acid (ωC8), which showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids controls their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8) is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

  4. Clove essential oil-in-cyclodextrin-in-liposomes in the aqueous and lyophilized states: From laboratory to large scale using a membrane contactor.

    PubMed

    Sebaaly, Carine; Charcosset, Catherine; Stainmesse, Serge; Fessi, Hatem; Greige-Gerges, Hélène

    2016-03-15

    This work is dedicated to prepare liposomal dry powder formulations of inclusion complexes of clove essential oil (CEO) and its main component eugenol (Eug). Ethanol injection method and membrane contactor were applied to prepare liposomes at laboratory and large scale, respectively. Various liposomal formulations were tested: (1) free hydroxypropyl-β-cyclodextrin loaded liposomes; (2) drug in hydroxypropyl-β-cyclodextrin in liposomes (DCL); (3) DCL2 obtained by double loading technique, where the drug is added in the organic phase and the inclusion complex in the aqueous phase. Liposomes were characterized for their particle size, polydispersity index, Zeta potential, morphology, encapsulation efficiency of CEO components and Eug loading rate. Reproducible results were obtained with both injection devices. Compared to Eug-loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. The DPPH(•) scavenging activity of Eug and CEO was maintained upon incorporation of Eug and CEO into DCL and DCL2. Contrary to DCL2, DCL formulations were stable after 1 month of storage at 4°C and upon reconstitution of the dried lyophilized cakes. Hence, DCL in aqueous and lyophilized forms, are considered as a promising carrier system to preserve volatile and hydrophobic drugs enlarging their application in cosmetic, pharmaceutical and food industries. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Laboratory studies of the low-temperature deliquescence of calcium chloride salts: Relevance to aqueous solutions on Mars and in the Antarctic Dry Valleys

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Chevrier, V.; Tolbert, M. A.

    2013-12-01

    There is significant interest in the possible existence of liquid water on current Mars. This water would likely exist as a brine in order to be stable on Mars today. It has been proposed that soil salts could form aqueous solutions through either the melting of ice by low-eutectic salts, or by the deliquescence of hygroscopic salts present in the Martian soil. The focus thus far has largely been on perchlorate species, which can melt ice at temperatures as low as 206 K and can deliquesce at relative humidity values as low as 38% RH. A Mars-relevant salt that has been neglected thus far is calcium chloride (CaCl2). Calcium has been reported to be an abundant cation at the Phoenix landing site and Mars Science Laboratory instruments have recently identified calcium as well. Simulations suggest subsurface CaCl2 is an ideal candidate to produce brines with seasonality consistent with observed recurring slope lineae (RSL) (Chevrier et al., 2012). Finally, the only terrestrial site where RSL-like features have been observed (near Don Juan Pond in the Antarctic Dry Valleys) contains abundant CaCl2. These seasonal slope streaks are thought to form when CaCl2 in the soil deliquesces due to contact with atmospheric water vapor (Dickson et al., 2013). It is important to understand how this CaCl2 interacts with water vapor at low temperatures relevant to Mars and the Martian analog sites. Here we use a Raman microscope and environmental cell to monitor the low-temperature (223 - 273 K) deliquescence (solid to aqueous phase transition) and efflorescence (aqueous to solid phase transition) of three hydration states of CaCl2 (dihydrate, tetrahydrate, hexahydrate). We have found that the deliquescence relative humidity (DRH) increases with increasing hydration state, which is an expected result. Average DRH values over the temperature range studied are 20.0 × 2.6% RH for the dihydrate, 31.8 × 6.3% RH for the tetrahydrate and 60.7 × 1.6% RH for the hexahydrate. Once the aqueous

  6. Laboratory investigation of flux reduction from dense non-aqueous phase liquid (DNAPL) partial source zone remediation by enhanced dissolution

    NASA Astrophysics Data System (ADS)

    Kaye, Andrew J.; Cho, Jaehyun; Basu, Nandita B.; Chen, Xiaosong; Annable, Michael D.; Jawitz, James W.

    2008-11-01

    This study investigated the benefits of partial removal of dense nonaqueous phase liquid (DNAPL) source zones using enhanced dissolution in eight laboratory scale experiments. The benefits were assessed by characterizing the relationship between reductions in DNAPL mass and the corresponding reduction in contaminant mass flux. Four flushing agents were evaluated in eight controlled laboratory experiments to examine the effects of displacement fluid property contrasts and associated override and underride on contaminant flux reduction ( Rj) vs. mass reduction ( Rm) relationships ( Rj( Rm)): 1) 50% ethanol/50% water (less dense than water), 2) 40% ethyl-lactate/60% water (more dense than water), 3) 18% ethanol/26% ethyl-lactate/56% water (neutrally buoyant), and 4) 2% Tween-80 surfactant (also neutrally buoyant). For each DNAPL architecture evaluated, replicate experiments were conducted where source zone dissolution was conducted with a single flushing event to remove most of the DNAPL from the system, and with multiple shorter-duration floods to determine the path of the Rj( Rm) relationship. All of the single-flushing experiments exhibited similar Rj( Rm) relationships indicating that override and underride effects associated with cosolvents did not significantly affect the remediation performance of the agents. The Rj( Rm) relationship of the multiple injection experiments for the cosolvents with a density contrast with water tended to be less desirable in the sense that there was less Rj for a given Rm. UTCHEM simulations supported the observations from the laboratory experiments and demonstrated the capability of this model to predict Rj( Rm) relationships for non-uniformly distributed NAPL sources.

  7. Phytochemistry, anti-inflammatory and analgesic activities of the aqueous leaf extract of Lagenaria breviflora (Cucurbitaceae) in laboratory animals.

    PubMed

    Adedapo, Adeolu; Adewuyi, Temitayo; Sofidiya, Margaret

    2013-03-01

    The plant, and especially the fruit of Lagenaria breviflora is widely used in folklore medicine in West Africa as a herbal remedy for the treatment of human measles, digestive disorders, and as wound antiseptics (e.g. umbilical incision wound), while livestock farmers use it for Newcastle disease and coccidiosis treatment in various animal species, especially poultry. The purpose of this study was to contribute with new information on this plant leaves extract effect, as few studies have considered their effects. We collected fresh leaves of Lagenaria breviflora from the school farm of the University of Ibadan, Nigeria in May 2011. Dried leaves were ground and a 200g sample was used to prepare the extract. The grounded leaves material was allowed to shake in 1000mL distilled water for 48h, in an orbital shaker at room temperature of 24 degreeC. The obtained extract was filtered and concentrated to dryness under reduced pressure at 40 degreeC, and the thick solution was lyophilized, for a final extract yield of 12.6%. Standard phytochemical methods were used to test the presence of saponins, alkaloids, tannins, anthraquinones, cardiac glycosides, cyanogenetic glycosides and flavonoids. The anti-inflammatory activity of the aqueous leaf extract of the plant was assessed using carrageenan-induced paw edema and histamine-induced paw edema in rats. The analgesic effect was determined using the acetic acid writhing method as well as formalin test in mice. Our results showed that the extract at 100 and 200mg/ kg body weight significantly reduced the formation of the oedema induced by carrageenan and histamine. In the acetic acid-induced writhing model, the extract showed a good analgesic effect characterized by reduction in the number of writhes when compared to the control. The extract caused dose-dependent decrease of licking time and licking frequency in rats injected with 2.5% formalin, signifying its analgesic effect. These results were however less than those of

  8. Laboratory Studies to Assess the Potential for Detection of Light Non-aqueous Phase Liquid in Contaminated Soils with Proton Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Bryar, T. R.; Knight, R. J.; Nielsen, T. P.

    2001-12-01

    The objective of this study was to determine the conditions necessary for the detection of LNAPL (Light Non-aqueous Phase Liquid) in contaminated soils using NMR (nuclear magnetic resonance) measurements. The study used toluene as the LNAPL and well characterized kaolinite and sand samples as the porous media; proton NMR measurements were made on partially saturated sand, clay and sand-clay mixtures. Proton NMR has the advantage over other surface geophysical techniques that it only responds to H atoms. However, since water is ubiquitous in the near surface, one of our main concerns was whether the signal from water would interfere with the detection of organic contaminants. We established that water and toluene were not resolved for sand or sand-clay mixtures with paramagnetic iron impurities less than or equal to 1.5 mg/g. However, for a sand-clay mixture for which the iron concentration was 1.9 mg/g, the two fluids were clearly resolved by laboratory NMR. These levels of paramagnetic materials are common in soils, especially those with some clay content. Provided that the soil has sufficient paramagnetic content for contaminant signal to be distinguishable from that of water, we found that the detection limit improves with signal to noise ratio (S/N) of the NMR data. For detection of LNAPL in the presence of water, NMR was capable of detecting as little as 20 mg toluene/g water, under ideal conditions in the laboratory. When we reduced signal quality to S/N = 80, the detection limit was only 140 mg toluene/g water. We also showed with synthetic data that the currently available surface loop NMR instrument (capable of S/N ~5) would be incapable of distinguishing organic contaminant at any concentration from water. The instrument would have to be improved to S/N = 20 to reliably detect even 1g LNAPL/g water.

  9. Effects of aqueous extracts from leaves and leaf litter on the abundance and diversity of soil gymnamoebae in laboratory microcosm cultures.

    PubMed

    Anderson, O Roger

    2005-01-01

    The distribution and abundance of microbiota in soil and litter may be significantly affected by the quality and quantity of localized patches of leaf organic matter. This study examined the relative effects of aqueous extracts of shed autumn leaves from American beech (Fagus grandifolia), sugar maple (Acer saccharum), red oak (Quercus rubra), and white oak (Quercus alba) on the density and diversity of gymnamoebae in laboratory cultures. Overall, the beech leaf extract produced the most growth of gymnamoebae followed by white oak with leaf extracts from maple and red oak producing least growth. Cultures using natural leaf litter from beneath beech trees had higher densities and diversity of gymnamoebae than leaf-litter cultures from a maple-oak stand. Soil microcosms confirmed that beech leaf extracts produced a higher density of gymnamoeba growth when added to soil cultures compared with maple and oak leaf extracts. Protein content, CHN (carbon and nitrogen content), and pH of the leaf extracts were assayed, but these alone were not sufficiently different to account for the effects. A dilution experiment indicated that some other concentration-dependent factor in the extract may produce the effects.

  10. Heat of Hydration of Low Activity Cementitious Waste Forms

    SciTech Connect

    Nasol, D.

    2015-07-23

    During the curing of secondary waste grout, the hydraulic materials in the dry mix react exothermally with the water in the secondary low-activity waste (LAW). The heat released, called the heat of hydration, can be measured using a TAM Air Isothermal Calorimeter. By holding temperature constant in the instrument, the heat of hydration during the curing process can be determined. This will provide information that can be used in the design of a waste solidification facility. At the Savannah River National Laboratory (SRNL), the heat of hydration and other physical properties are being collected on grout prepared using three simulants of liquid secondary waste generated at the Hanford Site. From this study it was found that both the simulant and dry mix each had an effect on the heat of hydration. It was also concluded that the higher the cement content in the dry materials mix, the greater the heat of hydration during the curing of grout.

  11. Manufacturing development of low activation vanadium alloys

    SciTech Connect

    Smith, J.P.; Johnson, W.R.; Baxi, C.B.

    1996-10-01

    General Atomics is developing manufacturing methods for vanadium alloys as part of a program to encourage the development of low activation alloys for fusion use. The culmination of the program is the fabrication and installation of a vanadium alloy structure in the DIII-D tokamak as part of the Radiative Divertor modification. Water-cooled vanadium alloy components will comprise a portion of the new upper divertor structure. The first step, procuring the material for this program has been completed. The largest heat of vanadium alloy made to date, 1200 kg of V-4Cr-4Ti, has been produced and is being converted into various product forms. Results of many tests on the material during the manufacturing process are reported. Research into potential fabrication methods has been and continues to be performed along with the assessment of manufacturing processes particularly in the area of joining. Joining of vanadium alloys has been identified as the most critical fabrication issue for their use in the Radiative Divertor Program. Joining processes under evaluation include resistance seam, electrodischarge (stud), friction and electron beam welding. Results of welding tests are reported. Metallography and mechanical tests are used to evaluate the weld samples. The need for a protective atmosphere during different welding processes is also being determined. General Atomics has also designed, manufactured, and will be testing a helium-cooled, high heat flux component to assess the use of helium cooled vanadium alloy components for advanced tokamak systems. The component is made from vanadium alloy tubing, machined to enhance the heat transfer characteristics, and joined to end flanges to allow connection to the helium supply. Results are reported.

  12. Rate of strontium sorption and the effects of variable aqueous concentrations of sodium and potassium on strontium distribution coefficients of a surficial sediment at the Idaho National Engineering Laboratory, Idaho

    USGS Publications Warehouse

    Bunde, R.L.; Rosentreter, J.J.; Liszewski, M.J.

    1998-01-01

    The rate of strontium sorption and the effects of variable aqueous concentrations of sodium and potassium on strontium sorption were measured as part of an investigation to determine strontium chemical transport properties of a surficial sediment at the Idaho National Engineering Laboratory (INEL), Idaho. Batch experimental techniques were used to determine the rate of strontium sorption and strontium distribution coefficients (K(d)s) between aqueous and solid phases. Rate experiments indicate that strontium in solution reached an apparent equilibrium with the sediment in 26 h. K(d)s were derived using the linear isotherm model at initial sodium concentrations from 100 to 5,000 mg/l and initial potassium concentrations from 2 to 150 mg/l. K(d)s ranged from 56 ?? 2 to 62 ?? 3 ml/g at initial aqueous concentrations of sodium and potassium equal to or less than 300 and 150 mg/l, respectively. K(d)s hinged from 4.7 ?? 0.2 to 19 ?? 1 ml/g with initial aqueous concentrations of sodium between 1,000 and 5,000 mg/l. These data indicate that sodium concentrations greater than 300 mg/l in wastewater increase the availability of strontium for transport beneath waste disposal ponds at the INEL by decreasing strontium sorption on the surficial sediment. Wastewater concentrations of sodium and potassium less than 300 and 150 mg/l, respectively, have little effect on the availability of strontium for transport.The rate of strontium sorption and the effects of variable aqueous concentrations of sodium and potassium on strontium sorption were measured as part of an investigation to determine strontium chemical transport properties of a surficial sediment at the Idaho National Engineering Laboratory (INEL), Idaho. Batch experimental techniques were used to determine the rate of strontium sorption and strontium distribution coefficients (Kds) between aqueous and solid phases. Rate experiments indicate that strontium in solution reached an apparent equilibrium with the sediment in 26

  13. LOW ACTIVITY WASTE FEED SOLIDS CARACTERIZATION AND FILTERABILITY TESTS

    SciTech Connect

    McCabe, D.; Crawford, C.; Duignan, M.; Williams, M.; Burket, P.

    2014-04-03

    The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant (WTP) that is currently under construction. The baseline plan for the WTP Pretreatment facility is to treat the waste, splitting it into High Level Waste (HLW) feed and Low Activity Waste (LAW) feed. Both waste streams are then separately vitrified as glass and sealed in canisters. The LAW glass will be disposed onsite in the Integrated Disposal Facility (IDF). There are currently no plans to treat the waste to remove technetium in the WTP Pretreatment facility, so its disposition path is the LAW glass. Options are being explored to immobilize the LAW portion of the tank waste, i.e., the LAW feed from the WTP Pretreatment facility. Removal of {sup 99}Tc from the LAW Feed, followed by off-site disposal of the {sup 99}Tc, would eliminate a key risk contributor for the IDF Performance Assessment (PA) for supplemental waste forms, and has potential to reduce treatment and disposal costs. Washington River Protection Solutions (WRPS) is developing some conceptual flow sheets for LAW treatment and disposal that could benefit from technetium removal. One of these flowsheets will specifically examine removing {sup 99}Tc from the LAW feed stream to supplemental immobilization. The conceptual flow sheet of the {sup 99}Tc removal process includes a filter to remove insoluble solids prior to processing the stream in an ion exchange column, but the characteristics and behavior of the liquid and solid phases has not previously been investigated. This report contains results of testing of a simulant that represents the projected composition of the feed to the Supplemental LAW process. This feed composition is not identical to the aqueous tank waste fed to the Waste Treatment Plant because it has been processed through WTP Pretreatment facility and therefore contains internal changes and recycle streams that will be generated within the WTP process. Although

  14. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS METHOD DEVELOPMENT

    SciTech Connect

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2007-08-08

    The x-ray fluorescence laboratory (XRF) in the Analytical Development Directorate (ADD) of the Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop an XRF analytical method that provides rapid turnaround time (<8 hours), while providing sufficient accuracy and precision to determine variations in waste.

  15. Reference values for the production of the aqueous fraction of the tear film measured by the standardized endodontic absorbent paper point test in different exotic and laboratory animal species.

    PubMed

    Lange, Rogério R; Lima, Leandro; Przydzimirski, Andreise C; Montiani-Ferreira, Fabiano

    2014-01-01

    The aqueous fraction of the tear film and the horizontal palpebral fissure length (HPFL) were measured in exotic and laboratory animals, specifically saffron finches (Sicalis flaveola), chestnut-bellied seed-finches (Sporophila angolensis), red-eared sliders (Trachemys scripta elegans), rats (Rattus norvegicus) and mice (Mus musculus). These species possess small eyes making it difficult to perform the typical Schirmer tear test. Measurement of the aqueous fraction of the tear was performed using the standardized endodontic absorbent paper point tear test (PPTT), accomplished with manual restraint by a single operator. The following results were obtained: saffron finches (n = 42)-HPFL (4.46 ± 0.09 mm) and PPTT (5.10 ± 0.26 mm); chestnut-bellied seed-finches (n = 38)-HPFL (4.77 ± 0.05 mm) and PPTT (4.11 ± 0.34 mm); red-eared sliders (n = 56)-HPFL (8.59 ± 0.08 mm) and PPTT (8.79 ± 0.38 mm); rats (n = 60)-HPFL (6.45 ± 0.09 mm) and PTT (6.18 ± 2.06 mm); and mice (n = 22)-HPFL (3.59 ± 0.27 mm) and PPTT (4.39 ± 1.45 mm).

  16. Stabilization of Savannah River National Laboartory (SRNL) Aqueous Waste by Fluidized Bed Steam Reforming (FBSR)

    SciTech Connect

    Jantzen, C

    2004-11-01

    The Savannah River National Laboratory (SRNL) is a multidisciplinary laboratory operated by Westinghouse Savannah River Company (WSRC) in Aiken, South Carolina. Research and development programs have been conducted at SRNL for {approx}50 years generating non-radioactive (hazardous and non-hazardous) and radioactive aqueous wastes. Typically the aqueous effluents from the R&D activities are disposed of from each laboratory module via the High Activity Drains (HAD) or the Low Activity Drains (LAD) depending on whether they are radioactive or not. The aqueous effluents are collected in holding tanks, analyzed and shipped to either H-Area (HAD waste) or the F/H Area Effluent Treatment Facility (ETF) (LAD waste) for volume reduction. Because collection, analysis, and transport of LAD and HAD waste is cumbersome and since future treatment of this waste may be curtailed as the F/H-Area evaporators and waste tanks are decommissioned, SRNL laboratory operations requested several proof of principle demonstrations of alternate technologies that would define an alternative disposal path for the aqueous wastes. Proof of principle for the disposal of SRNL HAD waste using a technology known as Fluidized Bed Steam Reforming (FBSR) is the focus of the current study. The FBSR technology can be performed either as a batch process, e.g. in each laboratory module in small furnaces with an 8'' by 8'' footprint, or in a semi-continuous Bench Scale Reformer (BSR). The proof of principle experiments described in this study cover the use of the FBSR technology at any scale (pilot or full scale). The proof of principle experiments described in this study used a non-radioactive HAD simulant.

  17. Application of low activation materials for near-term machines

    SciTech Connect

    Bloom, E.E.

    1988-01-01

    This paper contains viewgraphs on low activation materials used in thermonuclear reactors. Safety, economic and environmental factors are discussed. In particular waste disposal, shielding, and stress properties are included. (LSP)

  18. Charpy impact test results for low-activation ferritic alloys

    SciTech Connect

    Cannon, N.S.; Hu, W.L.; Gelles, D.S.

    1987-05-01

    The objective of this work is to evaluate the shift of the ductile to brittle transition temperature (DBTT) and the reduction of the upper shelf energy (USE) due to neutron irradiation of low activation ferritic alloys. Six low activation ferritic alloys have been tested following irradiation at 365/sup 0/C to 10 dpa and compared with control specimens in order to assess the effect of irradiation on Charpy impact properties.

  19. Removal of Ni(II) from aqueous solutions by an Arthrobacter viscosus biofilm supported on zeolite: from laboratory to pilot scale.

    PubMed

    Quintelas, Cristina; Pereira, Ricardo; Kaplan, Ecem; Tavares, Teresa

    2013-08-01

    This study discusses the retention of Ni(II) by Arthrobacter viscosus supported on zeolite 13 X in batch mode and in continuous mode, at laboratory scale and at pilot scale. The maximum adsorption capacities of 28.37, 20.21 and 11.13 mg/g were recorded for lab scale batch, for continuous lab scale minicolumns and for pilot scale bioreactors, respectively. The Sips isotherm and pseudo second order kinetics described well the observations registered in batch assays. The Adams-Bohart, Thomas and Yoon-Nelson models were applied to data obtained with the pilot scale bioreactor and a good fit was reached for Adams-Bohart and for Yoon-Nelson models. A fed-batch was performed at lab scale and the applicability of the biofilm in continuous mode for the described purpose was confirmed. The sorption mechanism was investigated in detail through FTIR, SEM and EDX analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Analysis of alternatives for immobilized low activity waste disposal

    SciTech Connect

    Burbank, D.A.

    1997-10-28

    This report presents a study of alternative disposal system architectures and implementation strategies to provide onsite near-surface disposal capacity to receive the immobilized low-activity waste produced by the private vendors. The analysis shows that a flexible unit strategy that provides a suite of design solutions tailored to the characteristics of the immobilized low-activity waste will provide a disposal system that best meets the program goals of reducing the environmental, health, and safety impacts; meeting the schedule milestones; and minimizing the life-cycle cost of the program.

  1. Corrosion Testing of Low-Activity Waste Glasses Fiscal Year 1998 Summary Report

    SciTech Connect

    BP McGrail; CW Lindenmeier; HT Schaef; PF Martin

    1998-11-25

    Analytical results are presented on the chemical composition and other physical properties of a glass, given the identification BNFL-A-S98, made at Pacific Northwest National Laboratory' that is representative of the low-activity waste glass composition proposed by BNFL, Inc.* for immobilization of envelope A double-shell tank wastes at the Hanford Site. This glass was prepared for use in a testing program to be conducted at Pacific Northwest National Laboratory and at Argonne National Laboratory for the purpose of characterizing its long-term corrosion behavior. Detailed examination of the glass microstructure using transmission electron microscopy showed structural features indicative of amorphous phase separation. A remelt was performed on a smaller batch (100 g) to ensure rapid cooling. The glass microstructure was reexamined and showed no evidence of phase separation. Selected long-term (some to 860 d) product consistency tests were terminated, and the leachates were analyzed on tests with three other representative low-activity waste glass formulations (L8- 1, L8-3, and L8-7). The results showed no evidence of corrosion rate acceleration at three times the duration of tests where another well-studied glass, LD6-5412, had been completely altered under identical test conditions. These tests (and others not discussed in this report) provide clear evidence that low-activity waste glasses with at least 20 mass% Na20 can be made that have excellent long-term corrosion resistance. However, glass composition has a large impact on long-term behavior and so careful experiments with several different techniques are essential to ensuring that a particular glass will have good long-term corrosion resistance.

  2. Permitting plan for the immobilized low-activity waste project

    SciTech Connect

    Deffenbaugh, M.L.

    1997-09-04

    This document addresses the environmental permitting requirements for the transportation and interim storage of the Immobilized Low-Activity Waste (ILAW) produced during Phase 1 of the Hanford Site privatization effort. Tri-Party Agreement (TPA) Milestone M-90 establishes a new major milestone, and associated interim milestones and target dates, governing acquisition and/or modification of facilities necessary for: (1) interim storage and disposal of Tank Waste Remediation Systems (TWRS) immobilized low-activity tank waste (ILAW) and (2) interim storage of TWRS immobilized HLW (IHLW) and other canistered high-level waste forms. Low-activity waste (LAW), low-level waste (LLW), and high-level waste (HLW) are defined by the TWRS, Hanford Site, Richland, Washington, Final Environmental Impact Statement (EIS) DOE/EIS-0189, August 1996 (TWRS, Final EIS). By definition, HLW requires permanent isolation in a deep geologic repository. Also by definition, LAW is ``the waste that remains after separating from high-level waste as much of the radioactivity as is practicable that when solidified may be disposed of as LLW in a near-surface facility according to the NRC regulations.`` It is planned to store/dispose of (ILAW) inside four empty vaults of the five that were originally constructed for the Group Program. Additional disposal facilities will be constructed to accommodate immobilized LLW packages produced after the Grout Vaults are filled. The specifications for performance of the low-activity vitrified waste form have been established with strong consideration of risk to the public. The specifications for glass waste form performance are being closely coordinated with analysis of risk. RL has pursued discussions with the NRC for a determination of the classification of the Hanford Site`s low-activity tank waste fraction. There is no known RL action to change law with respect to onsite disposal of waste.

  3. Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

    SciTech Connect

    Jantzen, C. M.; Pierce, E. M.; Bannochie, C. J.; Burket, P. R.; Cozzi, A. D.; Crawford, C. L.; Daniel, W. E.; Fox, K. M.; Herman, C. C.; Miller, D. H.; Missimer, D. M.; Nash, C. A.; Williams, M. F.; Brown, C. F.; Qafoku, N. P.; Neeway, J. J.; Valenta, M. M.; Gill, G. A.; Swanberg, D. J.; Robbins, R. A.; Thompson, L. E.

    2015-10-01

    This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Waste and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.

  4. Single-laboratory evaluation and modification of US EPA (Environmental Protection Agency) Methods 7470 and 7471 for the determination of mercury in aqueous and solid hazardous wastes (journal version)

    SciTech Connect

    Churchwell, M.E.; Livingston, R.L.; Sgontz, D.L.; Messman, J.D.; Beckert, W.F.

    1988-01-01

    The current U.S. Environmental Protection Agency (U.S. EPA) protocols for mercury determinations in aqueous and solid-waste samples (SW-846 Methods 7470 and 7471) using recirculating cold-vapor atomic absorption spectrometry (CV-AAS) were evaluated. The U.S. EPA protocols have been modified in a single-laboratory study to facilitate additional QC measures, to enhance detectability for low-level mercury concentrations, and to eliminate nonspecific vapor-absorption interferences. Volumetric manipulations for additional QC measures, if required, are facilitated by performing the sample digestions in Erlenmeyer flasks rather than in the current Biochemical Oxygen Demand (BOD) reduction-aeration bottles. Instrument detectability is improved 10-fold by using a gas sparging bottle as a dedicated reduction-aeration vessel and a silver wool-amalgamation CV-AAS system operated in an open configuration. The on-line amalgamation thermal-desorption process of the modified CV-AAS system eliminates interfering water and organic matrix vapors prior to the mercury absorption measurement. Good accuracy and precision have been obtained with the amalgamation CV-AAS system for the analyses of four reference sediment materials.

  5. Chemical composition measurements of the low activity waste (LAW) EPA-Series glasses

    SciTech Connect

    Fox, K.; Edwards, T. B.

    2016-03-01

    In this report, the Savannah River National Laboratory provides chemical analysis results for a series of simulated low activity waste glasses provided by Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 100.2 to 100.8 wt %, indicating recovery of all components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %.

  6. Low-activity solid waste measurements at Tokai Works

    SciTech Connect

    J. L. Parker; D. H. Beddingfield; H. O. Menlove

    1999-11-01

    There is significant interest in performing assay measurements of containerized low-activity solid waste. The authors have examined the cases of typical waste drum matrices containing small quantities of plutonium and fission products. They have discussed various measurement techniques and considered the advantages and disadvantages of each method. They present a new state-of-the-art passive neutron waste drum counter with minimum detectable mass limits far below those systems which they have previously fabricated.

  7. Characterization plan for the immobilized low-activity waste borehole

    SciTech Connect

    Reidel, S.P.; Reynolds, K.D.

    1998-03-01

    The US Department of Energy`s (DOE`s) Hanford Site has the most diverse and largest amounts of radioactive tank waste in the US. High-level radioactive waste has been stored at Hanford in large underground tanks since 1944. Approximately 209,000 m{sup 3} (54 Mgal) of waste are currently stored in 177 tanks. Vitrification and onsite disposal of low activity tank waste (LAW) are embodied in the strategy described in the Tri-Party Agreement. The tank waste is to be retrieved, separated into low- and high-level fractions, and then immobilized by private vendors. The DOE will receive the vitrified waste from private vendors and dispose of the low-activity fraction in the Hanford Site 200 East Area. The Immobilized Low-Activity Waste Disposal Complex (ILAWDC) is part of the disposal complex. This report is a plan to drill the first characterization borehole and collect data at the ILAWDC. This plan updates and revises the deep borehole portion of the characterization plan for the ILAWDC by Reidel and others (1995). It describes data collection activities for determining the physical and chemical properties of the vadose zone and the saturated zone at and in the immediate vicinity of the proposed ILAWDC. These properties then will be used to develop a conceptual geohydrologic model of the ILAWDC site in support of the Hanford ILAW Performance Assessment.

  8. SECONDARY WASTE MANAGEMENT STRATEGY FOR EARLY LOW ACTIVITY WASTE TREATMENT

    SciTech Connect

    TW, CRAWFORD

    2008-07-17

    This study evaluates parameters relevant to River Protection Project secondary waste streams generated during Early Low Activity Waste operations and recommends a strategy for secondary waste management that considers groundwater impact, cost, and programmatic risk. The recommended strategy for managing River Protection Project secondary waste is focused on improvements in the Effiuent Treatment Facility. Baseline plans to build a Solidification Treatment Unit adjacent to Effluent Treatment Facility should be enhanced to improve solid waste performance and mitigate corrosion of tanks and piping supporting the Effiuent Treatment Facility evaporator. This approach provides a life-cycle benefit to solid waste performance and reduction of groundwater contaminants.

  9. Hanford Immobilized Low-Activity Waste Product Acceptance Test Plan

    SciTech Connect

    Peeler, D.

    1999-06-22

    'The Hanford Site has been used to produce nuclear materials for the U.S. Department of Energy (DOE) and its predecessors. A large inventory of radioactive and mixed waste, largely generated during Pu production, exists in 177 underground single- and double-shell tanks. These wastes are to be retrieved and separated into low-activity waste (LAW) and high-level waste (HLW) fractions. The DOE is proceeding with an approach to privatize the treatment and immobilization of Handord''s LAW and HLW.'

  10. Hanford's Simulated Low Activity Waste Cast Stone Processing

    SciTech Connect

    Kim, Young

    2013-08-20

    Cast Stone is undergoing evaluation as the supplemental treatment technology for Hanford’s (Washington) high activity waste (HAW) and low activity waste (LAW). This report will only cover the LAW Cast Stone. The programs used for this simulated Cast Stone were gradient density change, compressive strength, and salt waste form phase identification. Gradient density changes show a favorable outcome by showing uniformity even though it was hypothesized differently. Compressive strength exceeded the minimum strength required by Hanford and greater compressive strength increase seen between the uses of different salt solution The salt waste form phase is still an ongoing process as this time and could not be concluded.

  11. Dissolution test for low-activity waste product acceptance.

    SciTech Connect

    Ebert, W. L.

    1998-05-20

    We have measured the mean and standard deviation of the solution concentrations of B, Na, and Si attained in replicate dissolution tests conducted at temperatures of 20, 40, and 70 C, for durations of 3 and 7 days, and at glass/water mass ratios of 1:10 and 1:1. These and other tests were conducted to evaluate the adequacy of the test methods specified in privatization contracts and to develop a data base that can be used to evaluate the reliability of reported results for tests performed on the waste products. Tests were conducted with a glass that we formulated to be similar to low-activity waste products that will be produced during the remediation of Hanford tank wastes. Statistical analyses indicated that, while the mean concentrations of B, Na, and Si were affected by the values of test parameters, the standard deviation of replicate tests was not. The precision of the tests was determined primarily by uncertainties in the analysis of the test solutions. Replicate measurements of other glass properties that must be reported for Hanford low-activity waste products were measured to evaluate the possible adoption of the glass used in these tests as a standard test material for the product acceptance process.

  12. Round-robin testing of a reference glass for low-activity waste forms

    SciTech Connect

    Ebert, W. L.; Wolf, S. F.

    1999-12-06

    A round robin test program was conducted with a glass that was developed for use as a standard test material for acceptance testing of low-activity waste glasses made with Hanford tank wastes. The glass is referred to as the low-activity test reference material (LRM). The program was conducted to measure the interlaboratory reproducibility of composition analysis and durability test results. Participants were allowed to select the methods used to analyze the glass composition. The durability tests closely followed the Product Consistency Test (PCT) Method A, except that tests were conducted at both 40 and 90 C and that parallel tests with a reference glass were not required. Samples of LRM glass that had been crushed, sieved, and washed to remove fines were provided to participants for tests and analyses. The reproducibility of both the composition and PCT results compare favorably with the results of interlaboratory studies conducted with other glasses. From the perspective of reproducibility of analysis results, this glass is acceptable for use as a composition standard for nonradioactive components of low-activity waste forms present at >0.1 elemental mass % and as a test standard for PCTS at 40 and 90 C. For PCT with LRM glass, the expected test results at the 95% confidence level are as follows: (1) at 40 C: pH = 9.86 {+-} 0.96; [B] = 2.30 {+-} 1.25 mg/L; [Na] = 19.7 {+-} 7.3 mg/L; [Si] = 13.7 {+-} 4.2 mg/L; and (2) at 90 C: pH = 10.92 {+-} 0.43; [B] = 26.7 {+-} 7.2 mg/L; [Na] = 160 {+-} 13 mg/L; [Si] = 82.0 {+-} 12.7 mg/L. These ranges can be used to evaluate the accuracy of PCTS conducted at other laboratories.

  13. Hanford immobilized low-activity tank waste performance assessment

    SciTech Connect

    Mann, F.M.

    1998-03-26

    The Hanford Immobilized Low-Activity Tank Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-level fraction of waste presently contained in Hanford Site tanks. The tank waste is the by-product of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste has been stored in underground single and double-shell tanks. The tank waste is to be retrieved, separated into low and high-activity fractions, and then immobilized by private vendors. The US Department of Energy (DOE) will receive the vitrified waste from private vendors and plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at Hanford until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to issue a Disposal Authorization Statement that would allow the modification of the four existing concrete disposal vaults to provide better access for emplacement of the immobilized low-activity waste (ILAW) containers; filling of the modified vaults with the approximately 5,000 ILAW containers and filler material with the intent to dispose of the containers; construction of the first set of next-generation disposal facilities. The performance assessment activity will continue beyond this assessment. The activity will collect additional data on the geotechnical features of the disposal sites, the disposal facility design and construction, and the long-term performance of the waste. Better estimates of long-term performance will be produced and reviewed on a regular basis. Performance assessments supporting closure of filled facilities will be issued seeking approval of those actions necessary to conclude active disposal facility operations. This report also analyzes the long-term performance of the currently planned disposal system as a basis

  14. Low-Activity Waste Feed Data Quality Objectives

    SciTech Connect

    MJ Truex; KD Wiemers

    1998-12-11

    This document describes characterization requirements for the Tank Waste Remediation System (TWRS) Waste Disposal Program's privatization efforts in support of low-activity waste (LAW) treatment and immobilization, This revised Data Quality Objective (DQO) replaces earlier documents (PNNL 1997; DOE-W 1998zq Wiemers 1996). Revision O of this DQO was completed to meet Tri-Party Agreement (TPA) target milestone M-60-14-TO1. Revision 1 updates the data requirements based on the contract issued `August 1998 (DOE-RL 1998b). In addition, sections of Revision O pertaining to "environmental planning" were not acceptable to the Washington State Department of Ecology (Ecology) and have been removed. Regulatory compliance for TWRS Privatization is being addressed in a separate DQO (Wiemers et al. 1998). The Project Hanford Management Contract (PHMC) Contractors and the private contractor may elect to complete issue-specific DQOS to accommodate their individual work scope.

  15. Water Chemistry Laboratory Manual.

    ERIC Educational Resources Information Center

    Jenkins, David; And Others

    This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar…

  16. Water Chemistry Laboratory Manual.

    ERIC Educational Resources Information Center

    Jenkins, David; And Others

    This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar…

  17. ITER divertor performance in the low-activation phase

    NASA Astrophysics Data System (ADS)

    Kukushkin, A. S.; Pacher, H. D.; Kotov, V.; Pacher, G. W.; Pitts, R. A.; Reiter, D.

    2013-12-01

    The paper presents results of SOLPS modelling of the edge plasma performance during the low-activation phase of ITER operation. The calculations show that the peak power loading of the divertor targets can reach the reactor-relevant level of 3 to 5 MW m-2, even without the fusion reactions, rendering commissioning of the high heat flux components possible in this phase. Parametrization of the output of the SOLPS runs for the predominantly helium plasma concerned by the studies reported here is performed, thus providing the boundary conditions for modelling of the core and allowing efficient integration of the core and edge models. This approach, using the ASTRA code for core simulations, is applied to the analysis of hydrogen accumulation in helium plasmas due to H pellet injection. The latter is the only available option for early testing of ELM pace-making as an ELM control tool assuming H-mode in hydrogen will not be possible. Critical dilution with H down to 70% He in the core plasma can be reached in only 0.5 to 1 s or even shorter, depending on the assumptions made.

  18. At tank Low Activity Feed Homogeneity Analysis Verification

    SciTech Connect

    DOUGLAS, J.G.

    2000-09-28

    This report evaluates the merit of selecting sodium, aluminum, and cesium-137 as analytes to indicate homogeneity of soluble species in low-activity waste (LAW) feed and recommends possible analytes and physical properties that could serve as rapid screening indicators for LAW feed homogeneity. The three analytes are adequate as screening indicators of soluble species homogeneity for tank waste when a mixing pump is used to thoroughly mix the waste in the waste feed staging tank and when all dissolved species are present at concentrations well below their solubility limits. If either of these conditions is violated, then the three indicators may not be sufficiently chemically representative of other waste constituents to reliably indicate homogeneity in the feed supernatant. Additional homogeneity indicators that should be considered are anions such as fluoride, sulfate, and phosphate, total organic carbon/total inorganic carbon, and total alpha to estimate the transuranic species. Physical property measurements such as gamma profiling, conductivity, specific gravity, and total suspended solids are recommended as possible at-tank methods for indicating homogeneity. Indicators of LAW feed homogeneity are needed to reduce the U.S. Department of Energy, Office of River Protection (ORP) Program's contractual risk by assuring that the waste feed is within the contractual composition and can be supplied to the waste treatment plant within the schedule requirements.

  19. Effects of Low Activity Solar Cycle on Orbital Debris Lifetime

    NASA Technical Reports Server (NTRS)

    Cable, Samual B.; Sutton, Eric K.; Lin, chin S.; Liou, J.-C.

    2011-01-01

    Long duration of low solar activity in the last solar minimum has an undesirable consequence of extending the lifetime of orbital debris. The AFRL TacSat-2 satellite decommissioned in 2008 has finally re-entered into the atmosphere on February 5th after more than one year overdue. Concerning its demise we have monitored its orbital decay and monthly forecasted Tacsat-2 re-entry since September 2010 by using the Orbital Element Prediction (OEP) model developed by the AFRL Orbital Drag Environment program. The model combines estimates of future solar activity with neutral density models, drag coefficient models, and an orbit propagator to predict satellite lifetime. We run the OEP model with solar indices forecast by the NASA Marshall Solar Activity Future Estimation model, and neutral density forecast by the MSIS-00 neutral density model. Based on the two line elements in 2010 up to mid September, we estimated at a 50% confidence level TacSat-2's re-entry time to be in early February 2011, which turned out to be in good agreement with Tacsat-2's actual re-entry date. The potential space weather effects of the coming low activity solar cycle on satellite lifetime and orbital debris population are examined. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of solar flux on the orbital debris population in the 200-600 km altitude environment. The results are discussed for developing satellite orbital drag application product.

  20. Human endothelial dihydrofolate reductase low activity limits vascular tetrahydrobiopterin recycling.

    PubMed

    Whitsett, Jennifer; Rangel Filho, Artur; Sethumadhavan, Savitha; Celinska, Joanna; Widlansky, Michael; Vasquez-Vivar, Jeannette

    2013-10-01

    Tetrahydrobiopterin (BH₄) is required for NO synthesis and inhibition of superoxide release from endothelial NO synthase. Clinical trials using BH₄ to treat endothelial dysfunction have produced mixed results. Poor outcomes may be explained by the rapid systemic and cellular oxidation of BH₄. One of the oxidation products of BH₄, 7,8-dihydrobiopterin (7,8-BH₂), is recycled back to BH₄ by dihydrofolate reductase (DHFR). This enzyme is ubiquitously distributed and shows a wide range of activity depending on species-specific factors and cell type. Information about the kinetics and efficiency of BH4 recycling in human endothelial cells receiving BH₄ treatment is lacking. To characterize this reaction, we applied a novel multielectrode coulometric HPLC method that enabled the direct quantification of 7,8-BH₂ and BH₄, which is not possible with fluorescence-based methodologies. We found that basal untreated BH₄ and 7,8-BH₂ concentrations in human endothelial cells (ECs) are lower than in bovine and murine endothelioma cells. Treatment of human ECs with BH₄ transiently increased intracellular BH₄ while accumulating the more stable 7,8-BH₂. This was different from bovine or murine ECs, which resulted in preferential BH₄ increase. Using BH₄ diastereomers, 6S-BH₄ and 6R-BH₄, the narrow contribution of enzymatic DHFR recycling to total intracellular BH₄ was demonstrated. Reduction of 7,8-BH₂ to BH₄ occurs at very slow rates in cells and needs supraphysiological levels of 7,8-BH₂, indicating this reaction is kinetically limited. Activity assays verified that human DHFR has very low affinity for 7,8-BH₂ (DHF7,8-BH₂) and folic acid inhibits 7,8-BH₂ recycling. We conclude that low activity of endothelial DHFR is an important factor limiting the benefits of BH4 therapies, which may be further aggravated by folate supplements.

  1. Endothelial human dihydrofolate reductase low activity limits vascular tetrahydrobiopterin recycling

    PubMed Central

    Whitsett, Jennifer; Filho, Artur Rangel; Sethumadhavan, Savitha; Celinska, Joanna; Widlansky, Michael; Vásquez-Vivar, Jeannette

    2013-01-01

    Tetrahydrobiopterin (BH4) is required for NO synthesis and inhibition of superoxide release from eNOS. Clinical trials using BH4 to treat endothelial dysfunction have produced mixed results. Poor outcomes may be explained by the rapid systemic and cellular oxidation of BH4. One of the oxidation products of BH4, 7,8-dihydrobiopterin (7,8-BH2), is recycled back to BH4 by dihydrofolate reductase (DHFR). This enzyme is ubiquitously distributed and shows a wide range of activity depending on species-specific factors and cell type. Information about the kinetics and efficiency of BH4 recycling in human endothelial cells receiving BH4 treatment is lacking. To characterize this reaction, we applied a novel multi-electrode coulometric HPLC method that enabled the direct quantification of 7,8-BH2 and BH4 which is not possible with fluorescent-based methodologies. We found that basal untreated BH4 and 7,8-BH2 concentrations in human ECs is lower than bovine and murine endothelioma cells. Treatment of human ECs with BH4 transiently increased intracellular BH4 while accumulating the more stable 7,8-BH2. This was different from bovine or murine ECs that resulted in preferential BH4 increase. Using BH4 diastereomers, 6S-BH4 and 6R-BH4, the narrow contribution of enzymatic DHFR recycling to total intracellular BH4 was demonstrated. Reduction of 7,8-BH2 to BH4 occurs at very slow rates in cells and needs supra-physiological levels of 7,8-BH2, indicating this reaction is kinetically limited. Activity assays verified that hDHFR has very low affinity for 7,8-BH2 (DHF7,8-BH2) and folic acid inhibits 7,8-BH2 recycling. We conclude that low activity of endothelial DHFR is an important factor limiting the benefits of BH4 therapies which may be further aggravated by folate supplements. PMID:23707606

  2. RADIOACTIVE DEMONSTRATIONS OF FLUIDIZED BED STEAM REFORMING AS A SUPPLEMENTARY TREATMENT FOR HANFORD'S LOW ACTIVITY WASTE AND SECONDARY WASTES

    SciTech Connect

    Jantzen, C.; Crawford, C.; Cozzi, A.; Bannochie, C.; Burket, P.; Daniel, G.

    2011-02-24

    The U.S. Department of Energy's Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. The Supplemental Treatment chosen will immobilize that portion of the retrieved LAW that is not sent to the WTP's LAW Vitrification facility into a solidified waste form. The solidified waste will then be disposed on the Hanford site in the Integrated Disposal Facility (IDF). In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as Cs-137, I-129, Tc-99, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap. The current waste disposal path for the WTP-SW is to recycle it to the supplemental LAW treatment to avoid a large steady state accumulation in the pretreatment-vitrification loop. Fluidized Bed Steam Reforming (FBSR) offers a moderate temperature (700-750 C) continuous method by which LAW and/or WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides

  3. Tangential Ultrafiltration of Aqueous "Saccharomyces Cerevisiae" Suspensions

    ERIC Educational Resources Information Center

    Silva, Carlos M.; Neves, Patricia S.; Da Silva, Francisco A.; Xavier, Ana M. R. B.; Eusebio, M. F. J.

    2008-01-01

    Experimental work on ultrafiltration is presented to illustrate the practical and theoretical principles of this separation technique. The laboratory exercise comprises experiments with pure water and with aqueous "Saccharomyces cerevisiae" (from commercial Baker's yeast) suspensions. With this work students detect the characteristic phenomena…

  4. Tangential Ultrafiltration of Aqueous "Saccharomyces Cerevisiae" Suspensions

    ERIC Educational Resources Information Center

    Silva, Carlos M.; Neves, Patricia S.; Da Silva, Francisco A.; Xavier, Ana M. R. B.; Eusebio, M. F. J.

    2008-01-01

    Experimental work on ultrafiltration is presented to illustrate the practical and theoretical principles of this separation technique. The laboratory exercise comprises experiments with pure water and with aqueous "Saccharomyces cerevisiae" (from commercial Baker's yeast) suspensions. With this work students detect the characteristic phenomena…

  5. Conceptual design statement of work for the immobilized low-activity waste interim storage facility project

    SciTech Connect

    Carlson, T.A., Fluor Daniel Hanford

    1997-02-06

    The Immobilized Low-Activity Waste Interim Storage subproject will provide storage capacity for immobilized low-activity waste product sold to the U.S. Department of Energy by the privatization contractor. This statement of work describes the work scope (encompassing definition of new installations and retrofit modifications to four existing grout vaults), to be performed by the Architect-Engineer, in preparation of a conceptual design for the Immobilized Low-Activity Waste Interim Storage Facility.

  6. Oxidant supply and aqueous photochemical SOA formation in cloud droplets and aqueous aerosol

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Ervens, B.; Lim, Y. B.

    2012-12-01

    Many recent laboratory, field and model studies point to significant contributions to the total secondary organic aerosol (SOA) budget from aqueous phase reactions in cloud droplets and aqueous aerosol particles. Laboratory studies of the photochemical oxidation of glyoxal and methylglyoxal in the aqueous phase show a strong dependence on the initial concentration of dissolved organics, with preferential formation of large molecules (dimers, oligomers) at the high concentrations found in ambient deliquesced aerosol particles. In such experimental studies OH radicals are produced in the aqueous phase (via hydrogen peroxide photolysis) and OH radical is assumed to be the major oxidant. An explicit aqueous photooxidation mechanism has been validated, in part, based on the observed temporal evolution of organic intermediates and products in these experiments. In this work, this mechanism was incorporated into multiphase process models (box, cloud parcel) in order to further explore aqueous SOA formation in dilute cloud droplets and concentrated aerosol particles. We found that the predicted SOA mass in both aqueous phases can be comparable despite the much lower liquid water content in aerosols, where oligomer formation is favored. Direct uptake from the gas phase was the largest source of OH radicals in the aqueous phase. In-situ production through the Fenton reaction (Fe), hydrogen peroxide and nitrate photolysis were minor sources. Since phase transfer is slower than the OH(aq) consumption by organics, modeled OH(aq) concentrations were smaller by 1-2 orders of magnitude than predicted based on thermodynamic equilibrium. Our model studies suggest that, unless there are substantial additional sources of OH radical in the aqueous phase, aqueous SOA formation will be oxidant limited. Since the phase transfer rate is a function of the drop (or particle) surface area, aqueous SOA formation may occur preferentially at or near the drop/particle surface (e.g., be surface

  7. Test Plan for Field Experiments to Support the Immobilized Low-Activity Waste Disposal Performance Assessment at the Hanford Site

    SciTech Connect

    Meyer, Philip D.; McGrail, B. Peter; Bacon, Diana H.

    2001-09-01

    Much of the data collected to support the Immobilized Low-Activity Waste Performance Assessment (ILAW PA) simulations have been obtained in the laboratory on a relatively small scale (less than 10 cm). In addition, the PA simulations themselves are currently the only means available to integrate the chemical and hydrologic processes involved in the transport of contaminants from the disposal facility into the environment. This report describes the test plan for field experiments to provide data on the hydraulic, transport, and geochemical characteristics of the near-field materials on a more representative (i.e., larger) scale than the laboratory data currently available. The experiments will also provide results that encompass a variety of transport processes likely to occur within the actual disposal facility. These experiments will thus provide the first integrated data on the ILAW facility performance and will provide a crucial dataset to evaluate the simulation-based estimates of overall facility performance used in the PA.

  8. Demonstration of sulfur solubility determinations in high waste loading, low-activity waste glasses

    SciTech Connect

    Fox, K. M.

    2016-04-25

    A method recommended by Pacific Northwest National Laboratory (PNNL) for sulfate solubility determinations in simulated low-activity waste glasses was demonstrated using three compositions from a recent Hanford high waste loading glass study. Sodium and sulfate concentrations in the glasses increased after each re-melting step. Visual observations of the glasses during the re-melting process reflected the changes in composition. The measured compositions showed that the glasses met the targeted values. The amount of SO3 retained in the glasses after washing was relatively high, ranging from 1.6 to 2.6 weight percent (wt %). Measured SnO2 concentrations were notably low in all of the study glasses. The composition of the wash solutions should be measured in future work to determine whether SnO2 is present with the excess sulfate washed from the glass. Increases in batch size and the amount of sodium sulfate added did not have a measureable impact on the amount of sulfate retained in the glass, although this was tested for only a single glass composition. A batch size of 250 g and a sodium sulfate addition targeting 7 wt %, as recommended by PNNL, will be used in future experiments.

  9. Evaluation of the single-pass flow-through test to support a low-activity waste specification

    SciTech Connect

    McGrail, B.P.; Peeler, D.K.

    1995-09-01

    A series of single-pass flow-through (SPFT) tests was performed on five reference low-activity waste glasses and a reference glass from the National Institute of Standards and Technology to support a product specification for low-activity waste (LAW) forms. The results showed that the SPFT test provides a means to quantitatively distinguish among LAW glass forms in terms of their forward reaction rate at a given temperature and solution pH. Two of the test glasses were also subjected to SPFT testing at Argonne National Laboratory (ANL). Forward reaction rate constants calculated from the ANL test data were 100 to over 1,000 times larger than the values obtained from the SPFT tests conducted at PNL. An analysis of the ANL results showed that they were inconsistent with independent measurements done on glasses of similar composition, the known pH-dependence of the forward rate, and with the results from low surface-area-to-volume, short duration product consistency tests. Because the data set obtained from the SPFT tests done at PNL was consistent with each of these same factors, a detailed examination of the test procedures used at both laboratories was performed to determine the cause(s) of the discrepancy. The omission of background subtraction in the data analysis procedure and the short-duration (on the order of hours) of the ANL tests are factors that may have significantly affected the calculated rates.

  10. Specular reflectance of aqueous solutions.

    NASA Technical Reports Server (NTRS)

    Querry, M. R.; Waring, R. C.; Holland, W. E.; Mansell, G. R.

    1971-01-01

    Description of two laboratory instruments for measuring the specular reflectance of aqueous solutions. The instruments are an organic-dye-laser spectrophotometer for the 360- to 650-nm wavelength region and a reflectometer accessory for a Perkin-Elmer E-system spectrophotometer which will operate in the 0.2- to 20-micron wavelength region. The reflectometer accessory has been used to measure the relative infrared specular reflectance in limited spectral regions for aqueous solutions of NaCl, K2SO4, ZnSO4, (NH4)2SO4, and NH4H2PO4 with radiant flux incident at about 70 deg and polarized perpendicular to the plane of incidence. The laser spectrometer has been used to measure the absolute reflectance of aqueous solutions of NaCl in the wavelength region from 575 to 610 nm for light incident at angles of about 60, 65, and 70 deg and polarized parallel to the plane of incidence.

  11. Specular reflectance of aqueous solutions.

    NASA Technical Reports Server (NTRS)

    Querry, M. R.; Waring, R. C.; Holland, W. E.; Mansell, G. R.

    1971-01-01

    Description of two laboratory instruments for measuring the specular reflectance of aqueous solutions. The instruments are an organic-dye-laser spectrophotometer for the 360- to 650-nm wavelength region and a reflectometer accessory for a Perkin-Elmer E-system spectrophotometer which will operate in the 0.2- to 20-micron wavelength region. The reflectometer accessory has been used to measure the relative infrared specular reflectance in limited spectral regions for aqueous solutions of NaCl, K2SO4, ZnSO4, (NH4)2SO4, and NH4H2PO4 with radiant flux incident at about 70 deg and polarized perpendicular to the plane of incidence. The laser spectrometer has been used to measure the absolute reflectance of aqueous solutions of NaCl in the wavelength region from 575 to 610 nm for light incident at angles of about 60, 65, and 70 deg and polarized parallel to the plane of incidence.

  12. A JOULE-HEATED MELTER TECHNOLOGY FOR THE TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    KELLY SE

    2011-04-07

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of joule-heated ceramic lined melters and their application to Hanford's low-activity waste.

  13. FLUIDIZED BED STEAM REFORMING FOR TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    HEWITT WM

    2011-04-08

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of fluidized bed steam reforming and its possible application to treat and immobilize Hanford low-activity waste.

  14. BULK VITRIFICATION TECHNOLOGY FOR THE TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    ARD KE

    2011-04-11

    This report is one of four reports written to provide background information regarding immobilization technologies under consideration for supplemental immobilization of Hanford's low-activity waste. This paper is intended to provide the reader with general understanding of Bulk Vitrification and how it might be applied to immobilization of Hanford's low-activity waste.

  15. Corrigendum to “Laboratory studies of perchlorate phase transitions: Support for metastable aqueous perchlorate solutions on Mars” [Earth Planet. Sci. Lett. 312 (3-4) (2011) 371-377

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Chevrier, V. F.; Baustian, K. J.; Wise, M. E.; Tolbert, M. A.

    2014-02-01

    Perchlorate salts, recently discovered on Mars, are known to readily absorb water vapor from the atmosphere and deliquesce into the aqueous phase at room temperature. Here we study the deliquescence (crystalline solid to liquid transition) and efflorescence (liquid to crystalline solid transition) of perchlorate salts at low temperatures relevant to Mars. A Raman microscope and environmental cell were used to determine the deliquescence relative humidity (DRH) and efflorescence relative humidity (ERH) of NaClO4 and Mg(ClO4)2 as a function of temperature and hydration state. We find that the deliquescence of anhydrous NaClO4 is only slightly dependent on temperature and occurs at ∼38% RH. The DRH of NaClO4ṡH2O increases with decreasing temperature from 51% at 273 K to 64% at 228 K. The DRH of Mg(ClO4)2ṡ6H2O also increases with decreasing temperature from 42% at 273 K to 55% at 223 K. The efflorescence of both NaClO4 and Mg(ClO4)2 salt solutions occurs at a lower RH than deliquescence due to the kinetic inhibition of crystallization. For all temperatures studied, the ERH values of NaClO4 and Mg(ClO4)2 are 13% and 19%, respectively. These results indicate perchlorate salts can exist as metastable, supersaturated solutions over a wide range of RH and temperature conditions. Summer diurnal temperature and relative humidity cycles at low latitudes on Mars could allow the surface salts to be aqueous for several hours per day.

  16. Supplemental Immobilization of Hanford Low-Activity Waste: Cast Stone Screening Tests

    SciTech Connect

    Westsik, Joseph H.; Piepel, Gregory F.; Lindberg, Michael J.; Heasler, Patrick G.; Mercier, Theresa M.; Russell, Renee L.; Cozzi, Alex; Daniel, William E.; Eibling, Russell E.; Hansen, E. K.; Reigel, Marissa M.; Swanberg, David J.

    2013-09-30

    More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in the HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second LAW immobilization facility will be needed for the expected volume of LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with the waste acceptance criteria for the disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF

  17. Aqueous foam toxicology evaluation and hazard review

    SciTech Connect

    Archuleta, M.M.

    1995-10-01

    Aqueous foams are aggregates of bubbles mechanically generated by passing air or other gases through a net, screen, or other porous medium that is wetted by an aqueous solution of surface-active foaming agents (surfactants). Aqueous foams are important in modem fire-fighting technology, as well as for military uses for area denial and riot or crowd control. An aqueous foam is currently being developed and evaluated by Sandia National Laboratories (SNL) as a Less-Than-Lethal Weapon for the National Institute of Justice (NIJ). The purpose of this study is to evaluate the toxicity of the aqueous foam developed for the NIJ and to determine whether there are any significant adverse health effects associated with completely immersing individuals without protective equipment in the foam. The toxicity of the aqueous foam formulation developed for NIJ is determined by evaluating the toxicity of the individual components of the foam. The foam is made from a 2--5% solution of Steol CA-330 surfactant in water generated at expansion ratios ranging from 500:1 to 1000:1. SteoI CA-330 is a 35% ammonium laureth sulfate in water and is produced by Stepan Chemical Company and containing trace amounts (<0.1%) of 1,4-dioxane. The results of this study indicate that Steol CA-330 is a non-toxic, mildly irritating, surfactant that is used extensively in the cosmetics industry for hair care and bath products. Inhalation or dermal exposure to this material in aqueous foam is not expected to produce significant irritation or systemic toxicity to exposed individuals, even after prolonged exposure. The amount of 1,4-dioxane in the surfactant, and subsequently in the foam, is negligible and therefore, the toxicity associated with dioxane exposure is not significant. In general, immersion in similar aqueous foams has not resulted in acute, immediately life-threatening effects, or chronic, long-term, non-reversible effects following exposure.

  18. MIPs in Aqueous Environments.

    PubMed

    Wan, Ying-chun; Ma, Hui-ting; Lu, Bin

    2015-01-01

    When organic solvent-compatible molecularly imprinted polymers (MIPs) are used in aqueous environment, how to reduce nonspecific binding is a major challenge. By modifying the binding solvents and introducing appropriate washing and elution steps, even relatively hydrophobic MIPs can gain optimal rebinding selectivity in aqueous conditions. Furthermore, water-compatible MIPs that can be used to treat aqueous samples directly have been prepared. The use of hydrophilic co-monomers, the controlled surface modification through controlled radical polymerization, and the new interfacial molecular imprinting methods are different strategies to prepare water-compatible MIPs. By combining MIPs with other techniques, both organic solvent-compatible and water-compatible MIPs can display better functional performances in aqueous conditions. Intensive studies on MIPs in aqueous conditions can provide new MIPs with much-improved compatibilities that will lead to more interesting applications in biomedicine and biotechnology.

  19. Stabilization of Gold Nanorods (GNRs) in Aqueous and Organic Environments by Select Surface Functionalization

    DTIC Science & Technology

    2016-01-01

    ARL-TR-7581 ● JAN 2016 US Army Research Laboratory Stabilization of Gold Nanorods (GNRs) in Aqueous and Organic Environments by...7581 ● JAN 2016 US Army Research Laboratory Stabilization of Gold Nanorods (GNRs) in Aqueous and Organic Environments by Select Surface... Gold Nanorods (GNRs) in Aqueous and Organic Environments by Select Surface Functionalization 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

  20. Hanford Low-Activity Waste Processing: Demonstration of the Off-Gas Recycle Flowsheet - 13443

    SciTech Connect

    Ramsey, William G.; Esparza, Brian P.

    2013-07-01

    Vitrification of Hanford Low-Activity Waste (LAW) is nominally the thermal conversion and incorporation of sodium salts and radionuclides into borosilicate glass. One key radionuclide present in LAW is technetium-99. Technetium-99 is a low energy, long-lived beta emitting radionuclide present in the waste feed in concentrations on the order of 1-10 ppm. The long half-life combined with a high solubility in groundwater results in technetium-99 having considerable impact on performance modeling (as potential release to the environment) of both the waste glass and associated secondary waste products. The current Hanford Tank Waste Treatment and Immobilization Plant (WTP) process flowsheet calls for the recycle of vitrification process off-gas condensates to maximize the portion of technetium ultimately immobilized in the waste glass. This is required as technetium acts as a semi-volatile specie, i.e. considerable loss of the radionuclide to the process off-gas stream can occur during the vitrification process. To test the process flowsheet assumptions, a prototypic off-gas system with recycle capability was added to a laboratory melter (on the order of 1/200 scale) and testing performed. Key test goals included determination of the process mass balance for technetium, a non-radioactive surrogate (rhenium), and other soluble species (sulfate, halides, etc.) which are concentrated by recycling off-gas condensates. The studies performed are the initial demonstrations of process recycle for this type of liquid-fed melter system. This paper describes the process recycle system, the waste feeds processed, and experimental results. Comparisons between data gathered using process recycle and previous single pass melter testing as well as mathematical modeling simulations are also provided. (authors)

  1. Near-Field Hydrology Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    SciTech Connect

    PD Meyer; RJ Serne

    1999-12-21

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method for disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in new-surface, shallow land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford ILAW Performance Assessment (PA) Activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists LMHC in its performance assessment activities. One of PNNL's tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information are contained in this report, the Near-Field Hydrology Data Package.

  2. Spectroelectrochemical Sensing of Aqueous Iron: An Experiment for Analytical Chemistry

    ERIC Educational Resources Information Center

    Shtoyko, Tanya; Stuart, Dean; Gray, H. Neil

    2007-01-01

    We have designed a laboratory experiment to illustrate the use of spectroelectrochemical techniques for determination of aqueous iron. The experiment described in this article is applicable to an undergraduate laboratory course in analytical chemistry. Students are asked to fabricate spectroelectrochemical sensors, make electrochemical and optical…

  3. Spectroelectrochemical Sensing of Aqueous Iron: An Experiment for Analytical Chemistry

    ERIC Educational Resources Information Center

    Shtoyko, Tanya; Stuart, Dean; Gray, H. Neil

    2007-01-01

    We have designed a laboratory experiment to illustrate the use of spectroelectrochemical techniques for determination of aqueous iron. The experiment described in this article is applicable to an undergraduate laboratory course in analytical chemistry. Students are asked to fabricate spectroelectrochemical sensors, make electrochemical and optical…

  4. Harmonization of the quantitative determination of volatile fatty acids profile in aqueous matrix samples by direct injection using gas chromatography and high-performance liquid chromatography techniques: Multi-laboratory validation study.

    PubMed

    Raposo, Francisco; Borja, Rafael; Cacho, Jesús A; Mumme, Jan; Mohedano, Ángel F; Battimelli, Audrey; Bolzonella, David; Schuit, Anthony D; Noguerol-Arias, Joan; Frigon, Jean-Claude; Peñuela, Gustavo A; Muehlenberg, Jana; Sambusiti, Cecilia

    2015-09-25

    The performance parameters of volatile fatty acids (VFAs) measurements were assessed for the first time by a multi-laboratory validation study among 13 laboratories. Two chromatographic techniques (GC and HPLC) and two quantification methods such as external and internal standard (ESTD/ISTD) were combined in three different methodologies GC/ESTD, HPLC/ESTD and GC/ISTD. Linearity evaluation of the calibration functions in a wide concentration range (10-1000mg/L) was carried out using different statistical parameters for the goodness of fit. Both chromatographic techniques were considered similarly accurate. The use of GC/ISTD, despite showing similar analytical performance to the other methodologies, can be considered useful for the harmonization of VFAs analytical methodology taking into account the normalization of slope values used for the calculation of VFAs concentrations. Acceptance criteria for VFAs performance parameters of the multi-laboratory validation study should be established as follows: (1) instrument precision (RSDINST≤1.5%); (2) linearity (R(2)≥0.998; RSDSENSITIVITY≤4%; REMAX≤8%; REAVER≤ 3%); (3) precision (RSD≤1.5%); (4) trueness (recovery of 97-103%); (5) LOD (≤3mg/L); and (6) LOQ (10mg/L).

  5. Experimental Design for Hanford Low-Activity Waste Glasses with High Waste Loading

    SciTech Connect

    Piepel, Gregory F.; Cooley, Scott K.; Vienna, John D.; Crum, Jarrod V.

    2015-07-24

    This report discusses the development of an experimental design for the initial phase of the Hanford low-activity waste (LAW) enhanced glass study. This report is based on a manuscript written for an applied statistics journal. Appendices A, B, and E include additional information relevant to the LAW enhanced glass experimental design that is not included in the journal manuscript. The glass composition experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC involving 15 LAW glass components. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directly applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this report. One of the glass components, SO3, has a solubility limit in glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO3 solubility limit had previously been modeled by a partial quadratic mixture model expressed in the relative proportions of the 14 other components. The partial quadratic mixture model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This report describes how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study. A layered design consists of points on an outer layer, and inner layer, and a center point. There were 18 outer-layer glasses chosen using optimal experimental design software to augment 147 existing glass compositions that were within the LAW glass composition experimental region. Then 13 inner-layer glasses were chosen with the software to augment the existing and outer

  6. Calculation of absorbed dose around a facility for disposing of low activity natural radioactive waste (C3-dump).

    PubMed

    Jansen, J T M; Zoetelief, J

    2005-01-01

    A C3-dump is a facility for disposing of low activity natural radioactive waste containing the uranium series 238U, the thorium series 232Th and 40K. Only the external radiation owing to gamma rays, X-rays and annihilation photons is considered in this study. For two situations--the semi-infinite slab and the tourist geometry--the conversion coefficients from specific activity to air kerma rate at 1 m above the relevant level are calculated. In the first situation the waste material is in contact with the air but in the tourist geometry it is covered with a 1.35 m thick layer. For the calculations, the Monte Carlo radiation transport code MCNP is used. The yield and photon energy for each radionuclide are according to the database of Oak Ridge National Laboratory. For the tourist situation, the depth-dose distribution through the covering layer is calculated and extrapolated to determine the exit dose.

  7. Laboratory Reagents

    SciTech Connect

    CARLSON, D.D.

    1999-10-08

    Replaced by WMH-310, Section 4.17. This document outlined the basic methodology for preparing laboratory reagents used in the 222-S Standards Laboratory. Included were general guidelines for drying, weighing, transferring, dissolving, and diluting techniques common when preparing laboratory reagents and standards. Appendix A contained some of the reagents prepared by the laboratory.

  8. Low-activity waste feed delivery -- Minimum duration between successive batches

    SciTech Connect

    Peters, B.B.

    1998-08-25

    The purpose of this study is to develop a defensible basis for establishing what ``minimum duration`` will provide acceptable risk mitigation for low-activity waste feed delivery to the privatization vendors. The study establishes a probabilistic-based duration for staging of low-activity waste feed batches. A comparison is made of the durations with current feed delivery plans and potential privatization vendor facility throughput rates.

  9. Design requirements document for project W-465, immobilized low activity waste interim storage

    SciTech Connect

    Burbank, D.A.

    1997-01-27

    The scope of this design requirements document is to identify the functions and associated requirements that must be performed to accept, transport, handle, and store immobilized low-activity waste produced by the privatized Tank Waste Remediation System treatment contractors. The functional and performance requirements in this document provide the basis for the conceptual design of the Tank Waste Remediation System Immobilized low-activity waste interim storage facility project and provides traceability from the program level requirements to the project design activity.

  10. Aqueous Alteration on Mars. Chapter 23

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W.; Morris, Richard V.; Clark, Benton C.

    2007-01-01

    Aqueous alteration is the change in composition of a rock, produced in response to interactions with H2O-bearing ices, liquids, and vapors by chemical weathering. A variety of mineralogical and geochemical indicators for aqueous alteration on Mars have been identified by a combination of surface and orbital robotic missions, telescopic observations, characterization of Martian meteorites, and laboratory and terrestrial analog studies. Mineralogical indicators for aqueous alteration include goethite (lander), jarosite (lander), kieserite (orbiter), gypsum (orbiter) and other Fe-, Mg-, and Ca-sulfates (landers), halides (meteorites, lander), phyllosilicates (orbiter, meteorites), hematite and nanophase iron oxides (telescopic, orbiter, lander), and Fe-, Mg-, and Ca-carbonates (meteorites). Geochemical indicators (landers only) for aqueous alteration include Mg-, Ca-, and Fe-sulfates, halides, and secondary aluminosilicates such as smectite. Based upon these indicators, several styles of aqueous alteration have been suggested on Mars. Acid-sulfate weathering (e.g., formation of jarosite, gypsum, hematite, and goethite), may occur during (1) the oxidative weathering of ultramafic igneous rocks containing sulfides, (2) sulfuric acid weathering of basaltic materials, and (3) acid fog (i.e., vapors rich in H2SO4) weathering of basaltic or basaltic-derived materials. Near-neutral or alkaline alteration occurs when solutions with pH near or above 7 move through basaltic materials and form phases such as phyllosilicates and carbonates. Very low water:rock ratios appear to have been prominent at most of the sites visited by landed missions because there is very little alteration (leaching) of the original basaltic composition (i.e., the alteration is isochemical or in a closed hydrologic system). Most of the aqueous alteration appears to have occurred early in the history of the planet (3 to 4.5 billion years ago); however, minor aqueous alteration may be occurring at the

  11. Inverse hydrochemical models of aqueous extracts tests

    SciTech Connect

    Zheng, L.; Samper, J.; Montenegro, L.

    2008-10-10

    Aqueous extract test is a laboratory technique commonly used to measure the amount of soluble salts of a soil sample after adding a known mass of distilled water. Measured aqueous extract data have to be re-interpreted in order to infer porewater chemical composition of the sample because porewater chemistry changes significantly due to dilution and chemical reactions which take place during extraction. Here we present an inverse hydrochemical model to estimate porewater chemical composition from measured water content, aqueous extract, and mineralogical data. The model accounts for acid-base, redox, aqueous complexation, mineral dissolution/precipitation, gas dissolution/ex-solution, cation exchange and surface complexation reactions, of which are assumed to take place at local equilibrium. It has been solved with INVERSE-CORE{sup 2D} and been tested with bentonite samples taken from FEBEX (Full-scale Engineered Barrier EXperiment) in situ test. The inverse model reproduces most of the measured aqueous data except bicarbonate and provides an effective, flexible and comprehensive method to estimate porewater chemical composition of clays. Main uncertainties are related to kinetic calcite dissolution and variations in CO2(g) pressure.

  12. Aqueous lithium air batteries

    DOEpatents

    Visco, Steven J.; Nimon, Yevgeniy S.; De Jonghe, Lutgard C.; Petrov, Alexei; Goncharenko, Nikolay

    2017-05-23

    Aqueous Li/Air secondary battery cells are configurable to achieve high energy density and prolonged cycle life. The cells include a protected a lithium metal or alloy anode and an aqueous catholyte in a cathode compartment. The aqueous catholyte comprises an evaporative-loss resistant and/or polyprotic active compound or active agent that partakes in the discharge reaction and effectuates cathode capacity for discharge in the acidic region. This leads to improved performance including one or more of increased specific energy, improved stability on open circuit, and prolonged cycle life, as well as various methods, including a method of operating an aqueous Li/Air cell to simultaneously achieve improved energy density and prolonged cycle life.

  13. Reflectance of aqueous solutions

    NASA Technical Reports Server (NTRS)

    Querry, M. R.

    1972-01-01

    The optical properties and optical constants of water and aqueous solutions were studied to develop an accurate tabulation of graphical representations of the optical constants through a broad spectrum. Manuscripts of articles are presented concerning extinction coefficients, relative specular reflectance, and temperature effect on the water spectrum. Graphs of absolute reflectance, phase shifts, index of refraction, and extinction coefficients for water, heavy water and aqueous solutions are included.

  14. Geochemical data package for the Hanford immobilized low-activity tank waste performance assessment (ILAW PA)

    SciTech Connect

    DI Kaplan; RJ Serne

    2000-02-24

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are stored in single- and double-shell tanks at the Hanford Site. The preferred method of disposing of the portion that is classified as low-activity waste is to vitrify the liquid/slurry and place the solid product in near-surface, shallow-land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford Immobilized Low-Activity Tank Waste (ILAW) Performance Assessment (PA) activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities, and the consequent transport of dissolved contaminants in the porewater of the vadose zone. Pacific Northwest National Laboratory assists LMHC in their performance assessment activities. One of the PNNL tasks is to provide estimates of the geochemical properties of the materials comprising the disposal facility, the disturbed region around the facility, and the physically undisturbed sediments below the facility (including the vadose zone sediments and the aquifer sediments in the upper unconfined aquifer). The geochemical properties are expressed as parameters that quantify the adsorption of contaminants and the solubility constraints that might apply for those contaminants that may exceed solubility constraints. The common parameters used to quantify adsorption and solubility are the distribution coefficient (K{sub d}) and the thermodynamic solubility product (K{sub sp}), respectively. In this data package, the authors approximate the solubility of contaminants using a more simplified construct

  15. Evaporation Of Hanford Waste Treatment Plant Direct Feed Low Activity Waste Effluent Management Facility Core Simulant

    SciTech Connect

    Adamson, D.; Nash, C.; Mcclane, D.; McCabe, D.

    2016-09-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation, and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator, in the Effluent Management Facility (EMF), and then return it to the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator, so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of the LMOGC stream would eliminate recycling of problematic components, and would reduce the need for closely integrated operation of the LAW melter and the Pretreatment Facilities. Long-term implementation of this option after WTP start-up would decrease the LAW vitrification mission duration and quantity of glass waste, amongst the other operational complexities such a recycle stream presents. In order to accurately plan for the disposition path, it is key to experimentally determine the fate of contaminants. To do this, testing is needed to accurately account for the buffering chemistry of the components, determine the achievable evaporation end point, identify insoluble solids that form, and determine the distribution of key regulatory-impacting constituents. The LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures, have limited solubility in the glass waste form, and represent a materials corrosion concern, such as halides and sulfate. Because this stream will recycle within WTP, these components will accumulate in the Melter Condensate

  16. Recharge Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    SciTech Connect

    MJ Fayer; EM Murphy; JL Downs; FO Khan; CW Lindenmeier; BN Bjornstad

    2000-01-18

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method of disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in near-surface, shallow-land burial facilities. The LMHC project to assess the performance of these disposal facilities is known as the Hanford ILAW Performance Assessment (PA) Activity, hereafter called the ILAW PA project. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require predictions of contaminant migration from the facility. To make such predictions will require estimates of the fluxes of water moving through the sediments within the vadose zone around and beneath the disposal facility. These fluxes, loosely called recharge rates, are the primary mechanism for transporting contaminants to the groundwater. Pacific Northwest National Laboratory (PNNL) assists LMHC in their performance assessment activities. One of the PNNL tasks is to provide estimates of recharge rates for current conditions and long-term scenarios involving the shallow-land disposal of ILAW. Specifically, recharge estimates are needed for a filly functional surface cover; the cover sideslope, and the immediately surrounding terrain. In addition, recharge estimates are needed for degraded cover conditions. The temporal scope of the analysis is 10,000 years, but could be longer if some contaminant peaks occur after 10,000 years. The elements of this report compose the Recharge Data Package, which provides estimates of recharge rates for the scenarios being considered in the 2001 PA. Table S.1 identifies the surface features and

  17. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS

    SciTech Connect

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2006-05-08

    Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence (XRF) spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop XRF analytical methods that provide the rapid turnaround time (<8 hours) requested by the WTP, while providing sufficient accuracy and precision to determine waste composition variations. For Phase 1a, SRNL (1) evaluated, selected, and procured an XRF instrument for WTP installation, (2) investigated three XRF sample methods for preparing the LAW sub-sample for XRF analysis, and (3) initiated scoping studies on AN-105 (Envelope A) simulant to determine the instrument's capability, limitations, and optimum operating parameters. After preliminary method development on simulants and the completion of Phase 1a activities, SRNL received approval from WTP to begin Phase 1b activities with the objective of optimizing the XRF methodology. Three XRF sample methods used for preparing the LAW sub-sample for XRF analysis were studied: direct liquid analysis, dried spot, and fused glass. The direct liquid method was selected because its major advantage is that the LAW can be analyzed directly without any sample alteration that could bias the method accuracy. It also is the fastest preparation technique--a typical XRF measurement could be completed in < 1hr after sample delivery. Except for sodium, the method detection limits (MDLs) for the most important analytes in solution, the hold point elements, were achieved by this method. The XRF detection limits are generally adequate for glass former batching and product composition reporting, but may be inadequate for some species (Hg, Cd, and Ba) important to

  18. Laboratory Tests

    MedlinePlus

    Laboratory tests check a sample of your blood, urine, or body tissues. A technician or your doctor ... compare your results to results from previous tests. Laboratory tests are often part of a routine checkup ...

  19. Conceptual design of low activation target chamber and components for the National Ignition Facility

    SciTech Connect

    Streckert, H.H.; Schultz, K.R.; Sager, G.T.; Kantner, R.D.

    1996-12-31

    The baseline design for the target chamber and chamber components for the National Ignition Facility (NIF) consists of aluminum alloy structural material. Low activation composite chamber and components have important advantages including enhanced environmental and safety characteristics and improved accessibility due to reduced neutron-induced radioactivity. A low activation chamber can be fabricated from carbon fiber reinforced epoxy using thick wall laminate technology similar to submarine bow dome fabrication for the U.S. Navy. A risk assessment analysis indicates that a composite chamber has a reasonably high probability of success, but that an aluminum alloy chamber represents a lower risk. Use of low activation composite materials for several chamber components such as the final optics assemblies, the target positioner and inserter, the diagnostics manipulator tubes, and the optics beam tubes would offer an opportunity to make significant reductions in post-shot radiation dose rate with smaller, less immediate impact on the NIF design. 7 refs., 3 figs.

  20. R&D of low activation ferritic steels for fusion in japanese universities*1

    NASA Astrophysics Data System (ADS)

    Kohyama, Akira; Kohno, Yutaka; Asakura, Kentaro; Kayano, Hideo

    1994-09-01

    Following the brief review of the R&D of low activation ferritic steels in Japanese universities, the status of 9Cr-2W type ferritic steels development is presented. The main emphasis is on mechanical property changes by fast neutron irradiation in FFTF. Bend test, tensile test, CVN test and in-reactor creep results are provided including some data about low activation ferritic steels with Cr variation from 2.25 to 12%. The 9Cr-2W ferritic steel, denoted as JLF-1, showed excellent mechanical properties under fast neutron irradiation as high as 60 dpa. As potential materials for DEMO and beyond, innovative oxide dispersion strengthened (ODS) quasi-amorphous low activation ferritic steels are introduced. The baseline properties, microstructural evolution under ion irradiation and the recent progress of new processes are provided.

  1. Immobilized low-activity waste interim storage facility, Project W-465 conceptual design report

    SciTech Connect

    Pickett, W.W.

    1997-12-30

    This report outlines the design and Total Estimated Cost to modify the four unused grout vaults for the remote handling and interim storage of immobilized low-activity waste (ILAW). The grout vault facilities in the 200 East Area of the Hanford Site were constructed in the 1980s to support Tank Waste disposal activities. The facilities were to serve project B-714 which was intended to store grouted low-activity waste. The existing 4 unused grout vaults, with modifications for remote handling capability, will provide sufficient capacity for approximately three years of immobilized low activity waste (ILAW) production from the Tank Waste Remediation System-Privatization Vendors (TWRS-PV). These retrofit modifications to the grout vaults will result in an ILAW interim storage facility (Project W465) that will comply with applicable DOE directives, and state and federal regulations.

  2. Rheology of aqueous foams

    NASA Astrophysics Data System (ADS)

    Dollet, Benjamin; Raufaste, Christophe

    2014-10-01

    Aqueous foams are suspensions of bubbles inside aqueous phases. Their multiphasic composition leads to a complex rheological behavior that is useful in numerous applications, from oil recovery to food/cosmetic processing. Their structure is very similar to the one of emulsions, so that both materials share common mechanical properties. In particular, the presence of surfactants at the gas-liquid interfaces leads to peculiar interfacial and dissipative properties. Foam rheology has been an active research topics and is already reported in several reviews, most of them covering rheometry measurements at the scale of the foam, coupled with interpretations at the local scale of bubbles or interfaces. In this review, we start following this approach, then we try to cover the multiscale features of aqueous foam flows, emphasizing regimes where intermediate length scales need to be taken into account or regimes fast enough regarding internal time scales so that the flow goes beyond the quasi-static limit. xml:lang="fr"

  3. Differential skeletal muscle proteome of high- and low-active mice

    PubMed Central

    Dangott, Lawrence J.; Schmitt, Emily E.; Vellers, Heather L.; Lightfoot, J. Timothy

    2014-01-01

    Physical inactivity contributes to cardiovascular disease, type II diabetes, obesity, and some types of cancer. While the literature is clear that there is genetic regulation of physical activity with existing gene knockout data suggesting that skeletal muscle mechanisms contribute to the regulation of activity, actual differences in end-protein expression between high- and low-active mice have not been investigated. This study used two-dimensional differential gel electrophoresis coupled with mass spectrometry to evaluate the proteomic differences between high-active (C57L/J) and low-active (C3H/HeJ) mice in the soleus and extensor digitorum longus (EDL). Furthermore, vivo-morpholinos were used to transiently knockdown candidate proteins to confirm their involvement in physical activity regulation. Proteins with higher expression patterns generally fell into the calcium-regulating and Krebs (TCA) cycle pathways in the high-active mice (e.g., annexin A6, P = 0.0031; calsequestrin 1; P = 0.000025), while the overexpressed proteins in the low-active mice generally fell into cytoskeletal structure- and electron transport chain-related pathways (e.g., ATPase, P = 0.031; NADH dehydrogenase, P = 0.027). Transient knockdown of annexin A6 and calsequestrin 1 protein of high-active mice with vivo-morpholinos resulted in decreased physical activity levels (P = 0.001). These data suggest that high- and low-active mice have unique protein expression patterns and that each pattern contributes to the peripheral capability to be either high- or low-active, suggesting that different specific mechanisms regulate activity leading to the high- or low-activity status of the animal. PMID:24505100

  4. Differential skeletal muscle proteome of high- and low-active mice.

    PubMed

    Ferguson, David P; Dangott, Lawrence J; Schmitt, Emily E; Vellers, Heather L; Lightfoot, J Timothy

    2014-04-15

    Physical inactivity contributes to cardiovascular disease, type II diabetes, obesity, and some types of cancer. While the literature is clear that there is genetic regulation of physical activity with existing gene knockout data suggesting that skeletal muscle mechanisms contribute to the regulation of activity, actual differences in end-protein expression between high- and low-active mice have not been investigated. This study used two-dimensional differential gel electrophoresis coupled with mass spectrometry to evaluate the proteomic differences between high-active (C57L/J) and low-active (C3H/HeJ) mice in the soleus and extensor digitorum longus (EDL). Furthermore, vivo-morpholinos were used to transiently knockdown candidate proteins to confirm their involvement in physical activity regulation. Proteins with higher expression patterns generally fell into the calcium-regulating and Krebs (TCA) cycle pathways in the high-active mice (e.g., annexin A6, P = 0.0031; calsequestrin 1; P = 0.000025), while the overexpressed proteins in the low-active mice generally fell into cytoskeletal structure- and electron transport chain-related pathways (e.g., ATPase, P = 0.031; NADH dehydrogenase, P = 0.027). Transient knockdown of annexin A6 and calsequestrin 1 protein of high-active mice with vivo-morpholinos resulted in decreased physical activity levels (P = 0.001). These data suggest that high- and low-active mice have unique protein expression patterns and that each pattern contributes to the peripheral capability to be either high- or low-active, suggesting that different specific mechanisms regulate activity leading to the high- or low-activity status of the animal.

  5. Design requirements document for project W-520, immobilized low-activity waste disposal

    SciTech Connect

    Ashworth, S.C.

    1998-08-06

    This design requirements document (DRD) identifies the functions that must be performed to accept, handle, and dispose of the immobilized low-activity waste (ILAW) produced by the Tank Waste Remediation System (TWRS) private treatment contractors and close the facility. It identifies the requirements that are associated with those functions and that must be met. The functional and performance requirements in this document provide the basis for the conceptual design of the Tank Waste Remediation System Immobilized Low-Activity Waste disposal facility project (W-520) and provides traceability from the program-level requirements to the project design activity.

  6. Non-aqueous cleaning solvent substitution

    NASA Technical Reports Server (NTRS)

    Meier, Gerald J.

    1994-01-01

    A variety of environmental, safety, and health concerns exist over use of chlorinated and fluorinated cleaning solvents. Sandia National Laboratories, Lawrence Livermore National Laboratories, and the Kansas City Division of AlliedSignal have combined efforts to focus on finding alternative cleaning solvents and processes which are effective, environmentally safe, and compliant with local, state, and federal regulations. An alternative solvent has been identified, qualified, and implemented into production of complex electronic assemblies, where aqueous and semi-aqueous cleaning processes are not allowed. Extensive compatibility studies were performed with components, piece-parts, and materials. Electrical testing and accelerated aging were used to screen for detrimental, long-term effects. A terpene, d-limonene, was selected as the solvent of choice, and it was found to be compatible with the components and materials tested. A brief history of the overall project will be presented, along with representative cleaning efficiency results, compatibility results, and residual solvent data. The electronics industry is constantly searching for proven methods and environmentally-safe materials to use in manufacturing processes. The information in this presentation will provide another option to consider on future projects for applications requiring high levels of quality, reliability, and cleanliness from non-aqueous cleaning processes.

  7. Continuous aqueous tritium monitor

    DOEpatents

    McManus, Gary J.; Weesner, Forrest J.

    1989-05-30

    An apparatus for a selective on-line determination of aqueous tritium concentration is disclosed. A moist air stream of the liquid solution being analyzed is passed through a permeation dryer where the tritium and moisture and selectively removed to a purge air stream. The purge air stream is then analyzed for tritium concentration, humidity, and temperature, which allows computation of liquid tritium concentration.

  8. CAST STONE TECHNOLOGY FOR THE TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    MINWALL HJ

    2011-04-08

    Cast stone technology is being evaluated for potential application in the treatment and immobilization of Hanford low-activity waste. The purpose of this document is to provide background information on cast stone technology. The information provided in the report is mainly based on a pre-conceptual design completed in 2003.

  9. Scenarios for the Hanford Immobilized Low-Activity Waste (ILAW) performance assessment

    SciTech Connect

    MANN, F.M.

    1999-03-17

    Scenarios describing representative exposure cases associated with the disposal of low activity waste from the Hanford Waste Tanks have been defined. These scenarios are based on guidance from the Department of Energy, the U.S. Nuclear Regulatory Commission, and previous Hanford waste disposal performance assessments.

  10. Preliminary Closure Plan for the Immobilized Low Activity Waste (ILAW) Disposal Facility

    SciTech Connect

    BURBANK, D.A.

    2000-08-31

    This document describes the preliminary plans for closure of the Immobilized Low-Activity Waste (ILAW) disposal facility to be built by the Office of River Protection at the Hanford site in southeastern Washington. The facility will provide near-surface disposal of up to 204,000 cubic meters of ILAW in engineered trenches with modified RCRA Subtitle C closure barriers.

  11. Improving the regulation and management of low-activity radioactive wastes.

    PubMed

    Leroy, David H; Ryan, Michael T; Wiley, John R

    2006-11-01

    This paper summarizes the first phase of a study in progress by a committee of the National Research Council's Board on Radioactive Waste Management. The Board initiated the study after observing that statutes and regulations administered by the federal and state agencies that control low-activity radioactive wastes have developed as a patchwork over almost 60 y. These controls usually reflect the enterprise or process that produced the waste rather than the waste's radiological hazard. Inconsistencies in the regulatory patchwork or its application may have led to overly restrictive controls for some low-activity wastes while others were neglected in comparison. In the first phase of this study, the committee reviewed current low-activity waste inventories, regulations, and management practices. This led the committee to develop five categories that encompass the spectrum of low-activity wastes and serve to illustrate gaps and inconsistencies in current regulations and management practices. The committee completed its first phase with four findings that will lead into the final phase of the study. This paper is excerpted from the committee's interim report that was issued in October 2003.

  12. Annual Summary of Immobilized Low Activity Tank Waste (ILAW) Performance Assessment for 2002

    SciTech Connect

    Mann, F. M.

    2002-08-01

    As required by the Department of Energy ( DOE), an annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) is necessary in each year in which a full performance assessment is not issued.

  13. Laboratory Microcomputing

    PubMed Central

    York, William B.

    1984-01-01

    Microcomputers will play a major role in the laboratory, not only in the calculation and interpretation of clinical test data, but also will have an increasing place of importance in the management of laboratory resources in the face of the transition from revenue generating to the cost center era. We will give you a glimpse of what can be accomplished with the management data already collected by many laboratories today when the data are processed into meaningful reports.

  14. Laboratory Building

    SciTech Connect

    Herrera, Joshua M.

    2015-03-01

    This report is an analysis of the means of egress and life safety requirements for the laboratory building. The building is located at Sandia National Laboratories (SNL) in Albuquerque, NM. The report includes a prescriptive-based analysis as well as a performance-based analysis. Following the analysis are appendices which contain maps of the laboratory building used throughout the analysis. The top of all the maps is assumed to be north.

  15. Purdue Hydrogen Systems Laboratory

    SciTech Connect

    Jay P Gore; Robert Kramer; Timothee L Pourpoint; P. V. Ramachandran; Arvind Varma; Yuan Zheng

    2011-12-28

    The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up. Efforts

  16. Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution

    DTIC Science & Technology

    1990-03-01

    IIC FILE COPY Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution Susan Taylor and Louise Parker March...Engineers Cold Regions Research & Engineering Laboratory Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution...14 iii Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution SUSAN TAYLOR AND LOUISE

  17. Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution

    DTIC Science & Technology

    1990-03-01

    CRREL *) Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution Susan Taylor and Louise Parker March...Engineering Laboratory Surface Changes in Well Casing Pipe Exposed to High Concentrations of Organics in Aqueous Solution Susan Taylor and Louise Parker March...SS304 (2000x) ..................................................................................... 14 iii Surface Changes in Well Casing Pipe Exposed to

  18. Aqueous chemistry of iodine

    SciTech Connect

    Toth, L.M.; Pannell, K.D.; Kirkland, O.L.

    1984-01-01

    The chemistry of iodine has been examined in aqueous solutions of pH 6 to 10 containing 2500 ppM boron as H/sub 3/BO/sub 3/ at temperatures up to 150/sup 0/C using absorption spectrophotometry to identify and monitor the iodine species present. Kinetic rate constants for the disproportionation of the HOI intermediate, 3HOI= IO/sub 3//sup -/ + 2I/sup -/ + 3H/sup +/, have been measured as a function of pH even though no direct spectral evidence for HOI itself has been observed. An HOI partition coefficient >10/sup 4/ has been estimated; results of ionic strength tests are consistent with HOI being present as an uncharged triatomic species in solution. Redox and radiation effects on the aqueous iodine chemistry have also been described. 11 refs., 2 figs., 3 tabs.

  19. Continuous aqueous tritium monitor

    DOEpatents

    McManus, G.J.; Weesner, F.J.

    1987-10-19

    An apparatus for a selective on-line determination of aqueous tritium concentration is disclosed. A moist air stream of the liquid solution being analyzed is passed through a permeation dryer where the tritium and moisture are selectively removed to a purge air stream. The purge air stream is then analyzed for tritium concentration, humidity, and temperature, which allows computation of liquid tritium concentration. 2 figs.

  20. Mars aqueous chemistry experiment

    NASA Technical Reports Server (NTRS)

    Clark, Benton C.; Mason, Larry W.

    1993-01-01

    The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

  1. A smart ink for the assessment of low activity photocatalytic surfaces.

    PubMed

    Mills, Andrew; O'Rourke, Christopher; Wells, Nathan

    2014-11-07

    The azo dye, basic blue 66 (BB66) is used in a photocatalyst activity indicator ink (paii) to assess the activity of low activity photocatalytic surfaces, such as commercial photocatalytic tiles and silicone contaminated self-cleaning glass. The BB66 paii is shown to respond much faster than a previously reported, resazurin (Rz) based paii, i.e. the use of a BB66 paii on low activity self-cleaning tiles was found to be >6 times faster than the Rz paii. The BB66 paii is also shown to be effective at assessing the activity of piece of commercial self-cleaning glass contaminated with a coating of silicone, on which the Rz ink, in contrast, failed to show any significant change in colour over the same time period.

  2. Fatigue strength of low-activation ferritic-martensitic high-chromium EK-181 steel

    NASA Astrophysics Data System (ADS)

    Kolmakov, A. G.; Terent'ev, V. F.; Prosvirnin, D. V.; Chernov, V. M.; Leont'eva-Smirnova, M. V.

    2016-04-01

    The static and cyclic mechanical properties of low-activation ferritic-martensitic EK-181 (Fe‒12Cr-2W-V-Ta-B-C) steel are studied in the temperature range 20-920°C (static tests) and at 20°C (cyclic tests). The fracture mechanisms of the steel under static tension and fatigue fracture conditions are analyzed by scanning electron microscopy.

  3. Association of low-activity MAOA allelic variants with violent crime in incarcerated offenders

    PubMed Central

    Stetler, Dean A.; Davis, Chad; Leavitt, Kathryn; Schriger, Ilana; Benson, Katie; Bhakta, Samir; Wang, Lam Chee; Oben, Cynthia; Watters, Matthew; Haghnegahdar, Tara; Bortolato, Marco

    2015-01-01

    The main enzyme for serotonin degradation, monoamine oxidase (MAO) A, has recently emerged as a key biological factor in the predisposition to impulsive aggression. Male carriers of low-activity variants of the main functional polymorphism of the MAOA gene (MAOA-uVNTR) have been shown to exhibit a greater proclivity to engage in violent acts. Thus, we hypothesized that low-activity MAOA-uVNTR alleles may be associated with a higher risk for criminal violence among male offenders. To test this possibility, we analyzed the MAOA-uVNTR variants of violent (n=49) and non-violent (n=40) male Caucasian and African-American convicts in a correctional facility. All participants were also tested with the Childhood Trauma Questionnaire (CTQ), Barratt Impulsivity Scale (BIS-11) and Buss-Perry Aggression Questionnaire (BPAQ) to assess their levels of childhood trauma exposure, impulsivity and aggression, respectively. Our results revealed a robust (P<0.0001) association between low-activity MAOA-uVNTR alleles and violent crime. This association was replicated in the group of Caucasian violent offenders (P<0.01), but reached only a marginal trend (P=0.08) in their African American counterparts. While violent crime charges were not associated with CTQ, BIS-11 and BPAQ scores, carriers of low-activity alleles exhibited a mild, yet significant (P<0.05) increase in BIS-11 total and attentional-impulsiveness scores. In summary, these findings support the role of MAOA gene as a prominent genetic determinant for criminal violence. Further studies are required to confirm these results in larger samples of inmates and evaluate potential interactions between MAOA alleles and environmental vulnerability factors. PMID:25082653

  4. Self-controlled feedback facilitates motor learning in both high and low activity individuals.

    PubMed

    Fairbrother, Jeffrey T; Laughlin, David D; Nguyen, Timothy V

    2012-01-01

    The purpose of this study was to determine if high and low activity individuals differed in terms of the effects of self-controlled feedback on the performance and learning of a movement skill. The task consisted of a blindfolded beanbag toss using the non-preferred arm. Participants were pre-screened according to their physical activity level using the International Physical Activity Questionnaire. An equal number of high activity (HA) and low activity (LA) participants were assigned to self-control (SC) and yoked (YK) feedback conditions, creating four groups: Self-Control-High Activity; Self-Control-Low Activity; Yoked-High Activity; and Yoked-Low Activity. SC condition participants were provided feedback whenever they requested it, while YK condition participants received feedback according to a schedule created by their SC counterpart. Results indicated that the SC condition was more accurate than the YK condition during acquisition and transfer phases, and the HA condition was more accurate than the LA condition during all phases of the experiment. A post-training questionnaire indicated that participants in the SC condition asked for feedback mostly after what they perceived to be "good" trials; those in the YK condition indicated that they would have preferred to receive feedback after "good" trials. This study provided further support for the advantages of self-controlled feedback when learning motor skills, additionally showing benefits for both active and less active individuals. The results suggested that the provision of self-controlled feedback to less active learners may be a potential avenue to teaching motor skills necessary to engage in greater amounts of physical activity.

  5. Association of low-activity MAOA allelic variants with violent crime in incarcerated offenders.

    PubMed

    Stetler, Dean A; Davis, Chad; Leavitt, Kathryn; Schriger, Ilana; Benson, Katie; Bhakta, Samir; Wang, Lam Chee; Oben, Cynthia; Watters, Matthew; Haghnegahdar, Tara; Bortolato, Marco

    2014-11-01

    The main enzyme for serotonin degradation, monoamine oxidase (MAO) A, has recently emerged as a key biological factor in the predisposition to impulsive aggression. Male carriers of low-activity variants of the main functional polymorphism of the MAOA gene (MAOA-uVNTR) have been shown to exhibit a greater proclivity to engage in violent acts. Thus, we hypothesized that low-activity MAOA-uVNTR alleles may be associated with a higher risk for criminal violence among male offenders. To test this possibility, we analyzed the MAOA-uVNTR variants of violent (n = 49) and non-violent (n = 40) male Caucasian and African-American convicts in a correctional facility. All participants were also tested with the Childhood Trauma Questionnaire (CTQ), Barratt Impulsivity Scale (BIS-11) and Buss-Perry Aggression Questionnaire (BPAQ) to assess their levels of childhood trauma exposure, impulsivity and aggression, respectively. Our results revealed a robust (P < 0.0001) association between low-activity MAOA-uVNTR alleles and violent crime. This association was replicated in the group of Caucasian violent offenders (P < 0.01), but reached only a marginal trend (P = 0.08) in their African American counterparts. While violent crime charges were not associated with CTQ, BIS-11 and BPAQ scores, carriers of low-activity alleles exhibited a mild, yet significant (P < 0.05) increase in BIS-11 total and attentional-impulsiveness scores. In summary, these findings support the role of MAOA gene as a prominent genetic determinant for criminal violence. Further studies are required to confirm these results in larger samples of inmates and evaluate potential interactions between MAOA alleles and environmental vulnerability factors.

  6. Soil decontamination using aqueous biphasic separation

    SciTech Connect

    Chaiko, D.J.; Mensah-Biney, R.; Gupta, D.

    1994-02-01

    This paper summarizes efforts to develop a biphasic extraction process for separating ultrafine particulate contaminants from soils having high amounts of silt and clay. This work has thus far dealt with the removal of refractory uranium particles from the soils at Fernald, Ohio. The separation process involves the selective partitioning of ultra-fine particles between two immiscible aqueous phases. The authors have conducted batch extraction studies and are now beginning to scaleup the process for pilot-plant testing at Argonne National Laboratory (ANL). The results of these extraction studies are discussed.

  7. How can mass participation physical activity events engage low-active people? A qualitative study.

    PubMed

    Early, Frances; Corcoran, Paula

    2013-08-01

    Regular, moderate physical activity reduces the risk of mortality and morbidity; however increasing the physical activity levels of less active people is a public health challenge. This study explores the potential of mass participation physical activity events to engage less active people, through analyzing the accounts of participants in 2 events who identified themselves as low-active before entering. Seven participants in a sponsored run and 7 in a sponsored walk were interviewed and transcripts were analyzed using grounded theory techniques. Participants had positive experiences encapsulated in 3 categories: Performing (physical completion of the event culminating in a sense of achievement); Relating (enjoying relationships); Soaking up the Atmosphere (enjoying the event ambience). The way in which these categories were manifested was affected by the event context. Mass participation events have potential to engage low-active people. The impact of participation resonated with factors that are positively associated with physical activity in other settings, and event characteristics matched key criteria for attracting low-active groups identified through social marketing research. Suggestions are given for how to capitalize on the findings for health promotion.

  8. Laboratory accreditation.

    PubMed

    Bradway, D E; Siegelman, F L

    1994-09-01

    An investigation of alleged data fraud at a pesticide analytical laboratory led EPA to take a closer look at the Good Laboratory Practice (GLP) inspection program. There was special focus on changes which might be made in the program to enhance the chances of detecting fraud in regulated studies. To this end, the Assistant Administrator of the Office of Prevention, Pesticides and Toxic Substances (OPPTS) requested EPA's Office of Inspector General (OIG) to examine the GLP program. Several reports were issued by the OIG, including the recommendation that a laboratory accreditation program be adopted. EPA has been examining ways to implement the OIG's recommendations, including (1) laboratory accreditation consisting of three components: document submission and assessment, site visit and assessment, and proficiency assessment; and (2) mandatory registration of all facilities participating in GLP-regulated studies, based on document submission and assessment. These two alternatives are compared, and the advantages and disadvantages of each are discussed.

  9. Aqueous and non-aqueous microchip electrophoresis with on-chip electrospray ionization mass spectrometry on replica-molded thiol-ene microfluidic devices.

    PubMed

    Tähkä, Sari M; Bonabi, Ashkan; Jokinen, Ville P; Sikanen, Tiina M

    2017-05-05

    This work describes aqueous and non-aqueous capillary electrophoresis on thiol-ene-based microfluidic separation devices that feature fully integrated and sharp electrospray ionization (ESI) emitters. The chip fabrication is based on simple and low-cost replica-molding of thiol-ene polymers under standard laboratory conditions. The mechanical rigidity and the stability of the materials against organic solvents, acids and bases could be tuned by adjusting the respective stoichiometric ratio of the thiol and allyl ("ene") monomers, which allowed us to carry out electrophoresis separation in both aqueous and non-aqueous (methanol- and ethanol-based) background electrolytes. The stability of the ESI signal was generally ≤10% RSD for all emitters. The respective migration time repeatabilities in aqueous and non-aqueous background electrolytes were below 3 and 14% RSD (n=4-6, with internal standard). The analytical performance of the developed thiol-ene microdevices was shown in mass spectrometry (MS) based analysis of peptides, proteins, and small molecules. The theoretical plate numbers were the highest (1.2-2.4×10(4)m(-1)) in ethanol-based background electrolytes. The ionization efficiency also increased under non-aqueous conditions compared to aqueous background electrolytes. The results show that replica-molding of thiol-enes is a feasible approach for producing ESI microdevices that perform in a stable manner in both aqueous and non-aqueous electrophoresis. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Aqueous Humor Dynamics: A Review

    PubMed Central

    Goel, Manik; Picciani, Renata G; Lee, Richard K; Bhattacharya, Sanjoy K

    2010-01-01

    Glaucoma is a family of optic neuropathies which cause irreversible but potentially preventable vision loss. Vision loss in most forms of glaucoma is related to elevated IOP with subsequent injury to the optic nerve. Secretion of aqueous humor and regulation of its outflow are physiologically important processes for maintaining IOP in the normal range. Thus, understanding the complex mechanisms that regulate aqueous humor circulation is essential for management of glaucoma. The two main structures related to aqueous humor dynamics are the ciliary body and the trabecular meshwork (TM). Three mechanisms are involved in aqueous humor formation: diffusion, ultrafiltration and active secretion. Active secretion is the major contributor to aqueous humor formation. The aqueous humor flow in humans follows a circadian rhythm, being higher in the morning than at night. The aqueous humor leaves the eye by passive flow via two pathways - the trabecular meshwork and the uveoscleral pathway. In humans, 75% of the resistance to aqueous humor outflow is localized within the TM with the juxtacanalicular portion of the TM being the main site of outflow resistance. Glycosaminoglycan deposition in the TM extracellular matrix (ECM) has been suggested to be responsible for increased outflow resistance at this specific site whereas others have suggested deposition of proteins, such as cochlin, obstruct the aqueous humor outflow through the TM. The uveoscleral outflow pathway is relatively independent of the intraocular pressure and the proportion of aqueous humor exiting the eye via the uveoscleral pathway decreases with age. PMID:21293732

  11. Aqueous shunts for glaucoma.

    PubMed

    Tseng, Victoria L; Coleman, Anne L; Chang, Melinda Y; Caprioli, Joseph

    2017-07-28

    Aqueous shunts are employed to control intraocular pressure (IOP) for people with primary or secondary glaucomas who fail or are not candidates for standard surgery. To assess the effectiveness and safety of aqueous shunts for reducing IOP in glaucoma compared with standard surgery, another type of aqueous shunt, or modification to the aqueous shunt procedure. We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 8), MEDLINE Ovid (1946 to August 2016), Embase.com (1947 to August 2016), PubMed (1948 to August 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to August 2016), ClinicalTrials.gov (www.clinicaltrials.gov); searched 15 August 2016, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 15 August 2016. We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 15 August 2016. We also searched the reference lists of identified trial reports and the Science Citation Index to find additional trials. We included randomized controlled trials that compared various types of aqueous shunts with standard surgery or to each other in eyes with glaucoma. Two review authors independently screened search results for eligibility, assessed the risk of bias, and extracted data from included trials. We contacted trial investigators when data were unclear or not reported. We graded the certainty of the evidence using the GRADE approach. We followed standard methods as recommended by Cochrane. We included 27 trials with a total of 2099 participants with mixed diagnoses and comparisons of interventions. Seventeen studies reported adequate methods of randomization, and seven reported adequate allocation concealment. Data collection and follow-up times varied.Four trials compared an aqueous shunt (Ahmed or Baerveldt) with trabeculectomy, of which

  12. Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students

    ERIC Educational Resources Information Center

    Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

    2011-01-01

    This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

  13. Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students

    ERIC Educational Resources Information Center

    Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

    2011-01-01

    This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

  14. Use of Pseudophase TLC in Teaching Laboratories.

    ERIC Educational Resources Information Center

    Armstrong, Daniel W.; And Others

    1984-01-01

    Suggests that pseudophase liquid chromatography, which uses aqueous surfactant solutions instead of organic solvents for the mobile phase, can be substituted for thin-layer chromatography in the introductory organic course. Outlines the method as it applies to common separations in the laboratory. (JN)

  15. Use of Pseudophase TLC in Teaching Laboratories.

    ERIC Educational Resources Information Center

    Armstrong, Daniel W.; And Others

    1984-01-01

    Suggests that pseudophase liquid chromatography, which uses aqueous surfactant solutions instead of organic solvents for the mobile phase, can be substituted for thin-layer chromatography in the introductory organic course. Outlines the method as it applies to common separations in the laboratory. (JN)

  16. Mars Aqueous Chemistry Experiment (MACE)

    NASA Technical Reports Server (NTRS)

    Benton, Clark C. (Editor)

    1995-01-01

    The concept of an aqueous-based chemical analyzer for Martian surface materials has been demonstrated to be feasible. During the processes of analysis, design, breadboarding, and most importantly, testing, it has become quite apparent that there are many challenges in implementing such a system. Nonetheless, excellent progress has been made and a number of problems which arose have been solved. The ability to conduct this work under a development environment which is separate and which precedes the project-level development has allowed us to find solutions to these implementation realities at low cost. If the instrument had been selected for a mission without this laboratory pre-project work, the costs of implementation would be much higher. In the four areas covered in Sections D, E, F, and G of this Final Report, outstanding progress has been made. There still remains the task of flight-qualifying certain of the components. This is traditionally done under the aegis of a Flight Project, but just as the concept development can be done at much lower cost when kept small and focused, so could the qualification program of critical parts benefit. We recommend, therefore, that NASA consider means of such qualifications and brass-boarding, in advance of final flight development. This is a generic recommendation, but hardware such as the Mars aqueous chemistry experiment (MACE) and other similarly-new concepts are particularly applicable. MACE now has wide versatility, in being able to reliably dispense both liquids and solids as chemical reagents to an entire suite of samples. The hardware and the experiment is much simpler than was developed for the Viking Biology instrument, yet can accomplish all the inorganic chemical measurements that the Viking desing was capable of. In addition, it is much more flexible and versatile to new experiment protocols (and reagents) than the Viking design ever could have been. MACE opens up the opportunity for many different scientific

  17. Mars aqueous chemistry experiment

    NASA Technical Reports Server (NTRS)

    Clark, Benton C.; Mason, Larry W.

    1994-01-01

    Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. The second year of the MACE project has shown significant progress in two major areas. MACE Instrument concept definition is a baseline design that has been generated for the complete MACE instrument, including definition of analysis modes, mass estimates and thermal model. The design includes multiple reagent reservoirs, 10 discrete analysis cells, sample manipulation capability, and thermal control. The MACE Measurement subsystems development progress is reported regarding measurement capabilities for aqueous ion sensing, evolved gas sensing, solution conductivity measurement, reagent addition (titration) capabilities, and optical sensing of suspended particles.

  18. Aqueous biphasic extraction

    SciTech Connect

    Chaiko, D.J.

    1994-02-01

    The aqueous biphasic separation (ABS) process, which involves the selective partitioning of ultrafine particles or solutes between two immiscible aqueous phases, is being evaluated for removing uranium from contaminated clay soils. Goal is to remove ultrafine U from the soil, leaving residues below regulatory cleanup limits. Tests were made using U-contaminated soil near the Fernald waste incinerator; over 80% of the soil is <45 {mu}m. All the biphasic systems used polyethylene glycol in combination with inorganic salt phase. Results: U was reduced from 500--600 mg/kg to about 90 mg/kg, and in some cases even down to 15 mg/kg. However, a soil sample from the Fernald storage pad area did not give encouraging results. Selective flocculation of soil particles and dissolution of U in the salt phase occurred but were not troublesome. Scaleup tests using uncontaminated clay mineral feed were successful. Operating costs for soil remediation using ABS is estimated to be $25--50 per ton. A pilot-scale column is being installed at ANL.

  19. Aqueous cleaning design presentation

    NASA Technical Reports Server (NTRS)

    Maltby, Peter F.

    1995-01-01

    The phase-out of CFC's and other ozone depleting chemicals has prompted industries to re-evaluate their present methods of cleaning. It has become necessary to find effective substitutes for their processes as well as to meet the new cleaning challenges of improved levels of cleanliness and to satisfy concerns about environmental impact of any alternative selected. One of the most popular alternatives being selected is aqueous cleaning. This method offers an alternative for removal of flux, grease/oil, buffing compound, particulates and other soils while minimizing environmental impact. What I will show are methods that can be employed in an aqueous cleaning system that will make it environmentally friendly, relatively simple to maintain and capable of yielding an even higher quality of cleanliness than previously obtained. I will also explore several drying techniques available for these systems and other alternatives along with recent improvements made in this technology. When considering any type of cleaning system, a number of variables should be determined before selecting the basic configuration. Some of these variables are: (1) Soil or contaminants being removed from your parts; (2) The level of cleanliness required; (3) The environmental considerations of your area; (4) Maintenance requirements; and (5) Operating costs.

  20. The Remote Handled Immobilization Low Activity Waste Disposal Facility Environmental Permits & Approval Plan

    SciTech Connect

    DEFFENBAUGH, M.L.

    2000-08-01

    The purpose of this document is to revise Document HNF-SD-ENV-EE-003, ''Permitting Plan for the Immobilized Low-Activity Waste Project, which was submitted on September 4, 1997. That plan accounted for the interim storage and disposal of Immobilized-Low Activity Waste at the existing Grout Treatment Facility Vaults (Project W-465) and within a newly constructed facility (Project W-520). Project W-520 was to have contained a combination of concrete vaults and trenches. This document supersedes that plan because of two subsequent items: (1) A disposal authorization that was received on October 25, 1999, in a U. S. Department of Energy-Headquarters, memorandum, ''Disposal Authorization Statement for the Department of Energy Hanford site Low-Level Waste Disposal facilities'' and (2) ''Breakthrough Initiative Immobilized Low-Activity Waste (ILAW) Disposal Alternative,'' August 1999, from Lucas Incorporated, Richland, Washington. The direction within the U. S. Department of Energy-Headquarters memorandum was given as follows: ''The DOE Radioactive Waste Management Order requires that a Disposal authorization statement be obtained prior to construction of new low-level waste disposal facility. Field elements with the existing low-level waste disposal facilities shall obtain a disposal authorization statement in accordance with the schedule in the complex-wide Low-Level Waste Management Program Plan. The disposal authorization statement shall be issued based on a review of the facility's performance assessment and composite analysis or appropriate CERCLA documentation. The disposal authorization shall specify the limits and conditions on construction, design, operations, and closure of the low-level waste facility based on these reviews. A disposal authorization statement is a part of the required radioactive waste management basis for a disposal facility. Failure to obtain a disposal authorization statement or record of decision shall result in shutdown of an operational

  1. Low-Active Male Adolescents: A Dose Response to High-Intensity Interval Training.

    PubMed

    Logan, Greig Robert Melrose; Harris, Nigel; Duncan, Scott; Plank, Lindsay D; Merien, Fabrice; Schofield, Grant

    2016-03-01

    High-intensity interval training (HIIT) is a potential alternative to traditionally recommended steady state exercise for providing health benefits in adolescents, yet its dose-response relationship in this cohort remains unclear, as does its translatability to real-world, nonclinical settings. The present study adopts a novel dose-response design to investigate the effects of undertaking 8 wk of HIIT on the cardiometabolic health of low-active male adolescents. Twenty-six male adolescents (age 16 ± 1 yr), identified as low active by nonparticipation in structured sport and physical education classes, were randomly assigned to one of five treatment groups. Corresponding with their group numbers (1-5), participants completed a number of HIIT "sets," which consisted of 4 repeated bouts of 20-s near-maximal exertion interspersed with 10-s passive recovery. Participants performed two HIIT sessions and one resistance training session each week for 8 wk. Baseline and follow-up health measures consisted of peak oxygen uptake (V˙O2peak) with an incremental ramp test to volitional exhaustion; body composition (including visceral fat mass, body fat, and lean tissue mass) with dual-energy x-ray absorptiometry; and lipid profile, glucose, insulin, and interleukin-6 from blood analysis. All health outcomes were analyzed as percentage changes, and data were modeled using a quadratic function to explore dose-response relationships. Significant improvements were observed for V˙O2peak (∼6%), body fat percentage (∼4%), visceral fat mass (∼10%), and waist circumference-to-height ratio (∼3%), but there was no clear effect of dose across groups. Low-active adolescent males performing a single HIIT set twice weekly, in addition to one resistance training session, gained meaningful improvements in fitness and body composition. Performing additional HIIT sets provided no additional improvements to those of the lowest dose in this study.

  2. The aqueous stability of a Mars salt analog: Instant Mars

    NASA Astrophysics Data System (ADS)

    Nuding, D. L.; Davis, R. D.; Gough, R. V.; Tolbert, M. A.

    2015-03-01

    Due to their stability in low-temperature conditions, aqueous salt solutions are the favored explanation for potential fluid features observed on present-day Mars. A salt analog was developed to closely match the individual cation and anion concentrations at the Phoenix landing site as reported by the Wet Chemistry Laboratory instrument. "Instant Mars" closely replicates correct relative concentrations of magnesium, calcium, potassium, sodium, perchlorate, chloride, and sulfate ions. A Raman microscope equipped with an environmental cellprobed liquid water uptake and loss by Instant Mars particles in a Mars relevant temperature and relative humidity (RH) environment. Our experiments reveal that Instant Mars particles can form stable, aqueous solutions starting at 56 ± 5% RH between 235 K and 243 K and persist as a metastable, aqueous solution at or above 13 ± 5% RH. Particle levitation using an optical trap examined the phase state and morphology of suspended Instant Mars particles exposed to changing water vapor conditions at room temperature. Levitation experiments indicate that water uptake began at 42 ± 8% RH for Instant Mars particles at 293 K. As RH is decreased at 293 K, the aqueous Instant Mars particles transition into a crystalline solid at 18 ± 7% RH. These combined results demonstrate that Instant Mars can take up water vapor from the surrounding environment and transition into a stable, aqueous solution. Furthermore, this aqueous Instant Mars solution can persist as a metastable, supersaturated solution in low-RH conditions.

  3. Aqueous complexes in f-element separation science

    SciTech Connect

    Nash, K.L.

    1997-11-01

    Powerful and/or selective extractant molecules/sorbents are a necessary component of an efficient ion exchange or solvent extraction separation process. However, selectivity in extraction and efficiency in process design often rely on reactions occurring in or moderated by the aqueous medium. The focus of this report in on the role of the aqueous phase and reaction that occur in aquo in defining separation efficiency and metal ion selectivity. As the programmatic emphasis is on actinide solution chemistry, the separations chemistry of the f-elements will be used to illustrate the principal role of aqueous chemistry in separation science. Most of the arguments developed apply to metal ion separations chemistry and processes in general. The discussion will consider the application of aqueous complexants, incorporation of aqueous complexants into the extracted complex, and the effect of properties of the aqueous medium on separation efficiency and selectivity. Several historically important separations processes will be considered along with recent efforts in these laboratories to design and characterize new water soluble complexants for improved f-element separations.

  4. Parametric Study to Characterize Low Activity Waste Tank Heat Removal Alternatives for Phase 1 Specification Development

    SciTech Connect

    GRENARD, C.E.

    2000-09-11

    Alternative for removing heat from Phase 1, low-activity waste feed double-shell tanks using the ventilation systems have been analyzed for Phase 1 waste feed delivery. The analysis was a parametric study using a model that predicted the waste temperatures for a range of primary and annulus ventilation system flow rates. The analysis was performed to determine the ventilation flow required to prevent the waste temperature from exceeding the Limiting Conditions for Operation limits during normal operation and the Safety Limits during off-normal events.

  5. Charpy impact test results for low activation ferritic alloys irradiated to 30 dpa

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1996-04-01

    Miniature specimens of six low activation ferritic alloys have been impact field tested following irradiation at 370{degrees}C to 30 dpa. Comparison of the results with those of control specimens and specimens irradiated to 10 dpa indicates that degradation in the impact behavior appears to have saturated by {approx}10 dpa in at least four of these alloys. The 7.5Cr-2W alloy referred to as GA3X appears most promising for further consideration as a candidate structural material in fusion reactor applications, although the 9Cr-1V alloy may also warrant further investigation.

  6. Technical basis for classification of low-activity waste fraction from Hanford site tanks

    SciTech Connect

    Petersen, C.A.

    1996-09-20

    The overall objective of this report is to provide a technical basis to support a U.S. Nuclear Regulatory Commission determination to classify the low-activity waste from the Hanford Site single-shell and double-shell tanks as `incidental` wastes after removal of additional radionuclides and immobilization.The proposed processing method, in addition to the previous radionuclide removal efforts, will remove the largest practical amount of total site radioactivity, attributable to high-level waste, for disposal is a deep geologic repository. The remainder of the waste would be considered `incidental` waste and could be disposed onsite.

  7. Technical basis for classification of low-activity waste fraction from Hanford site tanks

    SciTech Connect

    Petersen, C.A., Westinghouse Hanford

    1996-07-17

    The overall objective of this report is to provide a technical basis to support a U.S. Nuclear Regulatory Commission determination to classify the low-activity waste from the Hanford Site single-shell and double-shell tanks as `incidental` wastes after removal of additional radionuclides and immobilization.The proposed processing method, in addition to the previous radionuclide removal efforts, will remove the largest practical amount of total site radioactivity, attributable to high-level wastes, for disposal in a deep geologic repository. The remainder of the waste would be considered `incidental` waste and could be disposed onsite.

  8. School day segmented physical activity patterns of high and low active children.

    PubMed

    Fairclough, Stuart J; Beighle, Aaron; Erwin, Heather; Ridgers, Nicola D

    2012-06-06

    Variability exists in children's activity patterns due to the association with environmental, social, demographic, and inter-individual factors. This study described accelerometer assessed physical activity patterns of high and low active children during segmented school week days whilst controlling for potential correlates. Two hundred and twenty-three children (mean age: 10.7 ± 0.3 yrs, 55.6% girls, 18.9% overweight/obese) from 8 north-west England primary schools wore ActiGraph GT1M accelerometers for 7 consecutive days during autumn of 2009. ActiGraph counts were converted to minutes of moderate (MPA), vigorous (VPA) and moderate-to-vigorous (MVPA) physical activity. Children were classified as high active (HIGH) or low active (LOW) depending on the percentage of week days they accumulated at least 60 minutes of MVPA. Minutes spent in MPA and VPA were calculated for school time and non-school time and for five discrete school day segments (before-school, class time, recess, lunchtime, and after-school). Data were analysed using multi-level modelling. The HIGH group spent significantly longer in MPA and/or VPA before-school, during class time, lunchtime, and after-school (P < .05), independent of child and school level factors. The greatest differences occurred after-school (MPA = 5.5 minutes, VPA = 3.8 minutes, P < 0.001). MPA and VPA were also associated with gender, BMI z-score, number of enrolled children, playground area per student, and temperature, depending on the segment analysed.The additive effect of the segment differences was that the HIGH group accumulated 12.5 minutes per day more MVPA than the LOW group. HIGH active children achieved significantly more MPA and VPA than LOW active during four of the five segments of the school day when analyses were adjusted for potential correlates. Physical activity promotion strategies targeting low active children during discretionary physical activity segments of the day, and particularly

  9. School day segmented physical activity patterns of high and low active children

    PubMed Central

    2012-01-01

    Background Variability exists in children’s activity patterns due to the association with environmental, social, demographic, and inter-individual factors. This study described accelerometer assessed physical activity patterns of high and low active children during segmented school week days whilst controlling for potential correlates. Methods Two hundred and twenty-three children (mean age: 10.7 ± 0.3 yrs, 55.6% girls, 18.9% overweight/obese) from 8 north-west England primary schools wore ActiGraph GT1M accelerometers for 7 consecutive days during autumn of 2009. ActiGraph counts were converted to minutes of moderate (MPA), vigorous (VPA) and moderate-to-vigorous (MVPA) physical activity. Children were classified as high active (HIGH) or low active (LOW) depending on the percentage of week days they accumulated at least 60 minutes of MVPA. Minutes spent in MPA and VPA were calculated for school time and non-school time and for five discrete school day segments (before-school, class time, recess, lunchtime, and after-school). Data were analysed using multi-level modelling. Results The HIGH group spent significantly longer in MPA and/or VPA before-school, during class time, lunchtime, and after-school (P < .05), independent of child and school level factors. The greatest differences occurred after-school (MPA = 5.5 minutes, VPA = 3.8 minutes, P < 0.001). MPA and VPA were also associated with gender, BMI z-score, number of enrolled children, playground area per student, and temperature, depending on the segment analysed. The additive effect of the segment differences was that the HIGH group accumulated 12.5 minutes per day more MVPA than the LOW group. Conclusions HIGH active children achieved significantly more MPA and VPA than LOW active during four of the five segments of the school day when analyses were adjusted for potential correlates. Physical activity promotion strategies targeting low active children during discretionary physical

  10. Low-temperature irradiation effects on tensile and Charpy properties of low-activation ferritic steels

    NASA Astrophysics Data System (ADS)

    Shiba, Kiyoyuki; Hishinuma, Akimichi

    2000-12-01

    Tensile and Charpy properties of low-activation ferritic steel, F82H irradiated up to 0.8 dpa at low temperature below 300°C were investigated. The helium effect on these properties was also investigated using the boron isotope doping method. Neutron irradiation increased yield stress accompanied with ductility loss, and it also shifted the ductile-to-brittle transition temperature (DBTT) from -50°C to 0°C. Boron-doped F82H showed larger degradation in DBTT and ductility than boron-free F82H, while they had the same yield stress before and after irradiation.

  11. Particle Size Distribution Data From Existing Boreholes at the Immobilized Low-Activity Waste Site

    SciTech Connect

    Valenta, Michelle M.; Martin, Maria B.; Moreno, Jorge R.; Ferri, Rosalie M.; Horton, Duane G.; Reidel, Stephen P.

    2000-09-25

    This report provides particle size distribution data for samples near the Immobilized Low-Activity Waste (ILAW) Site that were archived in the Hanford Geotechnical Sample Library. Seventy-nine sediment samples were analyzed from four boreholes. Samples were collected from every ten feet in the boreholes. Eightly percent of the samples were classified as slightly gravelly sand. Fifteen percent were classified as gravelly sand, gravelly silty sand, or sandy gravels. These data indicate that the particle size of the sediment is consistent across the ILAW site and is dominated by sand in the upper part of the Hanford formation with more gravel rich units in the lower part.

  12. Status of ATR-A1 irradiation experiment on vanadium alloys and low-activation steels

    SciTech Connect

    Tsai, H.; Strain, R.V.; Gomes, I.; Chung, H.; Smith, D.L.

    1997-04-01

    The ATR-A1 irradiation experiment in the Advanced Test Reactor (ATR) was a collaborative U.S./Japan effort to study at low temperatures the effects of neutron damage on vanadium alloys. The experiment also contained a limited quantity of low-activation ferritic steel specimens from Japan as part of the collaboration agreement. The irradiation was completed on May 5, 1996, as planned, after achieving an estimated neutron damage of 4.7 dpa in vanadium. The capsule has since been kept in the ATR water canal for the required radioactivity cool-down. Planning is underway for disassembly of the capsule and test specimen retrieval.

  13. MICROSTRUCTURAL EXAMINATION OF LOW ACTIVATION FERRITIC STEELS FOLLOWING IRRADIATION IN ORR

    SciTech Connect

    Gelles, David S.

    2002-09-01

    Microstructural examinations are reported for a series of low activation steels containing Mn following irradiation in the Oak Ridge Reactor at 330 and 400 degrees C to approximately 10 dpa. Alloy compositions included 2Cr, 9Cr and 12Cr steels with V to 1.5 percent and W to 1.0 percent. Results include compositional changes in precipitates and microstructural changes as a function of composition and irradiation temperature. It is concluded that temperatures in ORR are on the order of 50 degrees C higher than anticipated.

  14. Formulation and preparation of Hanford Waste Treatment Plant direct feed low activity waste Effluent Management Facility core simulant

    SciTech Connect

    McCabe, Daniel J.; Nash, Charles A.

    2016-05-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it to the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of the LMOGC stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste, amongst the other problems such a recycle stream present. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate in the recycled Condensate and is a key outcome of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of this task was to formulate and prepare a simulant of the LAW Melter

  15. Development And Initial Testing Of Off-Gas Recycle Liquid From The WTP Low Activity Waste Vitrification Process - 14333

    SciTech Connect

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.; Taylor-Pashow, Kathryn M.; Adamson, Duane J.; Crawford, Charles L.; Morse, Megan M.

    2014-01-07

    The Waste Treatment and Immobilization Plant (WTP) process flow was designed to pre-treat feed from the Hanford tank farms, separate it into a High Level Waste (HLW) and Low Activity Waste (LAW) fraction and vitrify each fraction in separate facilities. Vitrification of the waste generates an aqueous condensate stream from the off-gas processes. This stream originates from two off-gas treatment unit operations, the Submerged Bed Scrubber (SBS) and the Wet Electrospray Precipitator (WESP). Currently, the baseline plan for disposition of the stream from the LAW melter is to recycle it to the Pretreatment facility where it gets evaporated and processed into the LAW melter again. If the Pretreatment facility is not available, the baseline disposition pathway is not viable. Additionally, some components in the stream are volatile at melter temperatures, thereby accumulating to high concentrations in the scrubbed stream. It would be highly beneficial to divert this stream to an alternate disposition path to alleviate the close-coupled operation of the LAW vitrification and Pretreatment facilities, and to improve long-term throughput and efficiency of the WTP system. In order to determine an alternate disposition path for the LAW SBS/WESP Recycle stream, a range of options are being studied. A simulant of the LAW Off-Gas Condensate was developed, based on the projected composition of this stream, and comparison with pilot-scale testing. The primary radionuclide that vaporizes and accumulates in the stream is Tc-99, but small amounts of several other radionuclides are also projected to be present in this stream. The processes being investigated for managing this stream includes evaporation and radionuclide removal via precipitation and adsorption. During evaporation, it is of interest to investigate the formation of insoluble solids to avoid scaling and plugging of equipment. Key parameters for radionuclide removal include identifying effective precipitation or ion

  16. Laboratory diagnosis

    USDA-ARS?s Scientific Manuscript database

    One of the first major goals of the microbiology laboratory is to isolate or detect clinically significant microorganisms from an affected site and, if more than one type of microorganism is present, to isolate them in approximately the same ratio as occurs in vivo. Whether an isolate is “clinically...

  17. Language Laboratories.

    ERIC Educational Resources Information Center

    Department of Education and Science, London (England).

    An educational survey of British language teachers concerning the use of the language laboratory focuses primarily on function, facilities, and performance specifications. Read in conjunction with two other reports published by the Ministry of Technology, this study is meant to help teachers, architects, and administrators develop language…

  18. Annual Summary of Immobilized Low Activity Tank Waste (ILAW) Performance Assessment

    SciTech Connect

    MANN, F M

    2000-05-01

    As required by the Department of Energy (DOE) order on radioactive waste management (DOE 1999a) as implemented by the Maintenance Plan for the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (Mann 2000a), an annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) must be submitted to DOE headquarters each year that a performance assessment is not submitted. Considering the results of data collection and analysis, the conclusions of the 1998 version of the ILAW PA (Mann 1998) as conditionally approved (DOE 1999b) remain valid, but new information indicates more conservatism in the results than previously estimated. A white paper (Mann 2000b) is attached as Appendix A to justify this statement. Recent ILAW performance estimates used on the waste form and geochemical data have resulted in increased confidence that the disposal of ILAW will meet performance objectives. The ILAW performance assessment program will continue to interact with science and technology activities, disposal facility design staff, and operations, as well as to continue to collect new waste form and disposal system data to further increase the understanding of the impacts of the disposal of ILAW. The next full performance assessment should be issued in the spring of 2001.

  19. The microstructural stability and mechanical properties of two low activation martensitic steels

    SciTech Connect

    Victoria, M.; Marmy, P.; Batawi, E.; Peters, J.; Briguet, C.; Rezai-Aria, F.; Gavillet, D.

    1996-12-31

    A desirable feature of future magnetically confined fusion reactors is the prospect of producing low level radioactive waste. In order to minimize the volume of radioactive material, in particular from the first wall and blanket structures, reduced long term activation alloys are being developed. Here, a low activation composition of a martensitic 9% Cr steel has been studied, based on the DIN (Deutsches Inst. fuer Normung) 1.4914 composition (MANET) but replacing Ni, Mo and Nb by the low activation elements W, V and Ta. Two casts were produced from high purity components, in which the effects of controlled additions of Mn (0.58 and 0.055 wt. %) and N (7 and 290 wt. ppm) were studied, so that the final compositions resulted in one cast with high Mn and low N (steel A) and the other with the opposite conditions (steel B). The two steels were evaluated in terms of structural stability and mechanical properties under tensile, fatigue and fracture toughness tests. It has been found that both alloys have a DBTT below room temperature, which in the case of the steel A is 70 K below that of MANET. Although the tensile strength is somewhat below that of the parent steel, both steels have longer fatigue life.

  20. Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

    SciTech Connect

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

    2013-08-29

    The purpose of this Process Development Plan is to summarize the objectives and plans for the technology development activities for an alternative path for disposition of the recycle stream that will be generated in the Hanford Waste Treatment Plant Low Activity Waste (LAW) vitrification facility (LAW Recycle). This plan covers the first phase of the development activities. The baseline plan for disposition of this stream is to recycle it to the WTP Pretreatment Facility, where it will be concentrated by evaporation and returned to the LAW vitrification facility. Because this stream contains components that are volatile at melter temperatures and are also problematic for the glass waste form, they accumulate in the Recycle stream, exacerbating their impact on the number of LAW glass containers. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and reducing the halides in the Recycle is a key component of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, this stream does not have a proven disposition path, and resolving this gap becomes vitally important. This task seeks to examine the impact of potential future disposition of this stream in the Hanford tank farms, and to develop a process that will remove radionuclides from this stream and allow its diversion to another disposition path, greatly decreasing the LAW vitrification mission duration and quantity of glass waste. The origin of this LAW Recycle stream will be from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover or precipitates of scrubbed components (e.g. carbonates). The soluble

  1. Lunar laboratory

    SciTech Connect

    Keaton, P.W.; Duke, M.B.

    1986-01-01

    An international research laboratory can be established on the Moon in the early years of the 21st Century. It can be built using the transportation system now envisioned by NASA, which includes a space station for Earth orbital logistics and orbital transfer vehicles for Earth-Moon transportation. A scientific laboratory on the Moon would permit extended surface and subsurface geological exploration; long-duration experiments defining the lunar environment and its modification by surface activity; new classes of observations in astronomy; space plasma and fundamental physics experiments; and lunar resource development. The discovery of a lunar source for propellants may reduce the cost of constructing large permanent facilities in space and enhance other space programs such as Mars exploration. 29 refs.

  2. Laboratory accreditation

    SciTech Connect

    Pettit, R.B.

    1998-08-01

    Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

  3. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-98 Status Report

    SciTech Connect

    Herbst, A.K.; McCray, J.A.; Rogers, A.Z.; Simmons, R.F.; Palethrope, S.J.

    1999-03-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

  4. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program, FY-98 Status Report

    SciTech Connect

    Herbst, A.K.; Rogers, A.Z.; McCray, J.A.; Simmons, R.F.; Palethorpe, S.J.

    1999-03-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

  5. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-98 Status Report

    SciTech Connect

    Herbst, Alan Keith; Mc Cray, John Alan; Rogers, Adam Zachary; Simmons, R. F.; Palethorpe, S. J.

    1999-03-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

  6. Unusual mercury isotopic compositions in aqueous environment

    NASA Astrophysics Data System (ADS)

    Chen, J.; Hintelmann, H.; Zheng, W.; Feng, X.; Cai, H.; Wang, Z.; Yuan, S.

    2014-12-01

    Preliminary studies have demonstrated both mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) of Hg isotopes in natural samples. Laboratory experiments showed that photochemical reduction of inorganic mercury (iHg) and methylmercury (MMHg) and liquid-vapour evaporation could produce MIF of odd Hg isotopes. This was thought to cause the MIF actually observed in aquatic organisms. Although isotopic measurements of Hg in aqueous environment would give direct evidence, little data was reported for surface water samples. Recent work reported, unexpectedly, positive MIF of odd Hg isotopes in both precipitation and ambient air, in contrast with the prediction of laboratory experiments and measurements of Hg accumulated in lichens . Intriguingly, MIF of even-mass Hg isotope (200Hg) was also recently determined in the atmosphere. In contrast with the now mainstream observation of odd Hg isotope anomaly that has several theoretical explanations, the hitherto mysterious even Hg isotope anomalies were neither reported in laboratory experiments, nor predicted by isotope fractionation mechanisms, highlighting the importance of further study on Hg isotopes in variable systems. Our measurements of lichens and lake water samples from different countries show for the first time significant Δ200Hg in surface terrestrial reservoirs, realizing a direct connection of even Hg isotope anomaly in the terrestrial reservoirs to the atmospheric deposition, and fulfilling the gap of Δ200Hg between the atmosphere and the terrestrial receptors. The specific odd Hg isotope compositions determined in lake waters also support the atmosphere contribution, and may be directly linked to the high Δ199Hg values largely determined and manifested on the top of aqueous food web. Our data show that the watershed Hg input is another contributing source, rather than the in-lake processes, to explain the lacustrine Hg isotope anomalies. Interestingly, lake sediments are isotopically

  7. MINERALIZING, STEAM REFORMING TREATMENT OF HANFORD LOW-ACTIVITY WASTE (a.k.a. INEEL/EXT-05-02526)

    SciTech Connect

    A. L. Olson; N. R. Soelberg; D. W. Marshall; G. L. Anderson

    2005-02-01

    The U.S. Department of Energy (DOE) documented, in 2002, a plan for accelerating cleanup of the Hanford Site, located in southeastern Washington State, by at least 35 years. A key element of the plan was acceleration of the tank waste program and completion of ''tank waste treatment by 2028 by increasing the capacity of the planned Waste Treatment Plant (WTP) and using supplemental technologies for waste treatment and immobilization.'' The plan identified steam reforming technology as a candidate for supplemental treatment of as much as 70% of the low-activity waste (LAW). Mineralizing steam reforming technology, offered by THOR Treatment Technologies, LLC would produce a denitrated, granular mineral waste form using a high-temperature fluidized bed process. A pilot scale demonstration of the technology was completed in a 15-cm-diameter reactor vessel. The pilot scale facility was equipped with a cyclone separator and heated sintered metal filters for particulate removal, a thermal oxidizer for reduced gas species and NOx destruction, and a packed activated carbon bed for residual volatile species capture. The pilot scale equipment is owned by the DOE, but located at the Science and Technology Applications Research (STAR) Center in Idaho Falls, ID. Pilot scale testing was performed August 2–5, 2004. Flowsheet chemistry and operational parameters were defined through a collaborative effort involving Idaho National Engineering and Environmental Laboratory (INEEL), Savannah River National Laboratory (SRNL), and THOR Treatment Technologies personnel. Science Application International Corporation, owners of the STAR Center, personnel performed actual pilot scale operation. The pilot scale test achieved a total of 68.4 hours of cumulative/continuous processing operation before termination in response to a bed de-fluidization condition. 178 kg of LAW surrogate were processed that resulted in 148 kg of solid product, a mass reduction of about 17%. The process achieved

  8. A Strategy to Conduct an Analysis of the Long-Term Performance of Low-Activity Waste Glass in a Shallow Subsurface Disposal System at Hanford

    SciTech Connect

    Neeway, James J.; Pierce, Eric M.; Freedman, Vicky L.; Ryan, Joseph V.; Qafoku, Nikolla

    2014-08-04

    The federal facilities located on the Hanford Site in southeastern Washington State have been used extensively by the U.S. government to produce nuclear materials for the U.S. strategic defense arsenal. Currently, the Hanford Site is under the stewardship of the U.S. Department of Energy (DOE) Office of Environmental Management (EM). A large inventory of radioactive and mixed waste resulting from the production of nuclear materials has accumulated, mainly in 177 underground single- and double-shell tanks located in the central plateau of the Hanford Site (Mann et al., 2001). The DOE-EM Office of River Protection (ORP) is proceeding with plans to immobilize and permanently dispose of the low-activity waste (LAW) fraction onsite in a shallow subsurface disposal facility (the Integrated Disposal Facility [IDF]). Pacific Northwest National Laboratory (PNNL) was contracted to provide the technical basis for estimating radionuclide release from the engineered portion of the IDF (the source term) as part of an immobilized low-activity waste (ILAW) glass testing program to support future IDF performance assessments (PAs).

  9. NMR Studies on the Aqueous Phase Photochemical Degradation of TNT

    SciTech Connect

    Thorn, Kevin A.; Cox, Larry G.

    2008-04-06

    Aqueous phase photochemical degradation of 2,4,6-trinitrotoluene (TNT) is an important pathway in several environments, including washout lagoon soils, impact craters from partially detonated munitions that fill with rain or groundwater, and shallow marine environments containing unexploded munitions that have corroded. Knowledge of the degradation products is necessary for compliance issues on military firing ranges and formerly used defense sites. Previous laboratory studies have indicated that UV irradiation of aqueous TNT solutions results in a multicomponent product mixture, including polymerization compounds, that has been only partially resolved by mass spectrometric analyses. This study illustrates how a combination of solid and liquid state 1H, 13C, and 15N NMR spectroscopy, including two dimensional analyses, provides complementary information on the total product mixture from aqueous photolysis of TNT, and the effect of reaction conditions. Among the degradation products detected were amine, amide, azoxy, azo, and carboxylic acid compounds.

  10. Aqueous humor changes after experimental filtering surgery.

    PubMed

    Radius, R L; Herschler, J; Claflin, A; Fiorentino, G

    1980-02-01

    We studied aqueous humor of rhesus and owl monkeys for its effect on the growth of subconjunctival fibroblasts in tissue culture. Aqueous humor samples obtained before glaucoma surgery inhibited the initiation of growth of fibroblasts. However, postoperative aqueous humor samples supported growth of fibroblasts. The change in aqueous humor physiology lasted for up to two months after glaucoma surgery. Our study indicated that possibly material added to the postoperative aqueous humor inactivates an inhibitor normally present in primary aqueous humor. An alternative explanation would be that primary aqueous humor, in contrast to secondary aqueous humor, lacks sufficient nutrient material to support fibroblast growth in tissue culture.

  11. Idaho Chemical Processing Plant low-activity waste grout stabilization development program FY-97 status report

    SciTech Connect

    Herbst, A.K.; Marshall, D.W.; McCray, J.A.

    1998-02-01

    The general purpose of the Grout Development Program is to solidify and stabilize the liquid low-activity wastes (LAW) generated at the Idaho Chemical Processing Plant (ICPP). It is anticipated that LAW will be produced from the following: (1) chemical separation of the tank farm high-activity sodium-bearing waste, (2) retrieval, dissolution, and chemical separation of the aluminum, zirconium, and sodium calcines, (3) facility decontamination processes, and (4) process equipment waste. Grout formulation studies for sodium-bearing LAW, including decontamination and process equipment waste, continued this fiscal year. A second task was to develop a grout formulation to solidify potential process residual heels in the tank farm vessels when the vessels are closed.

  12. Office of River Protection Advanced Low-Activity Waste Glass Research and Development Plan

    SciTech Connect

    Kruger, A. A.; Peeler, D. K.; Kim, D. S.; Vienna, J. D.; Piepel, G. F.; Schweiger, M. J.

    2015-11-23

    The U.S. Department of Energy Office of River Protection (ORP) has initiated and leads an integrated Advanced Waste Glass (AWG) program to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product performance requirements. The integrated ORP program is focused on providing a technical, science-based foundation for making key decisions regarding the successful operation of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) facilities in the context of an optimized River Protection Project (RPP) flowsheet. The fundamental data stemming from this program will support development of advanced glass formulations, key product performance and process control models, and tactical processing strategies to ensure safe and successful operations for both the low-activity waste (LAW) and high-level waste vitrification facilities. These activities will be conducted with the objective of improving the overall RPP mission by enhancing flexibility and reducing cost and schedule.

  13. Low-Activation Joining of SiC/SiC Composites for Fusion Applications

    SciTech Connect

    Henager, Charles H.; Kurtz, Richard J.

    2011-10-01

    Abstract Research at PNNL has been directed at high-strength, low-activation joints using solid-state displacement reactions. This paper reports on further development and optimization of displacement reaction joints for the TITAN collaboration. The results reveal that fully dense and high-quality joints between SiC-composite bars are fabricated at 1623K to 1723K using 30 MPa pressure in purified argon atmospheres. Scanning electron micrographs reveal typical interpenetrating phase microstructures in the joints, which are about 10 µm thick. Blocky SiC particles are observed to nucleate preferentially at the SiC-joint interface but are more plate-like within the joint. X-ray spectroscopy reveals a uniform distribution of constituent elements consistent with the interpenetrating phases.

  14. Fracture toughness of low activation ferritic steel (JLF-1) weld joint at room temperature

    NASA Astrophysics Data System (ADS)

    Nishimura, A.; Inoue, N.; Muroga, T.

    1998-10-01

    A low activation ferritic steel has been developed for a candidate of a structural material of nuclear fusion reactors. Since welding must be performed when the support structures are constructed, fracture toughness of the weld joint has to be characterized as well as the base metal in an engineering sense. In this report, 25 mm thick plates of JLF-1, which contains 9% Cr and 2% W, are butt-welded by a tungsten inert gas (TIG) procedure, and the fracture toughness of the base plate and the weld metal is investigated at room temperature using 1T and 0.5T CT specimens. The base metal reveals high fracture toughness of about 430 kJ/m 2. However, the weld metal showed unstable big pop-ins. One sample fractured in a nearly elastic condition and another sample showed a toughness of over 400 kJ/m 2.

  15. Geologic Data Package for 2001 Immobilized Low-Activity Waste Performance Assessment

    SciTech Connect

    SP Reidel; DG Horton

    1999-12-21

    This database is a compilation of existing geologic data from both the existing and new immobilized low-activity waste disposal sites for use in the 2001 Performance Assessment. Data were compiled from both surface and subsurface geologic sources. Large-scale surface geologic maps, previously published, cover the entire 200-East Area and the disposal sites. Subsurface information consists of drilling and geophysical logs from nearby boreholes and stored sediment samples. Numerous published geological reports are available that describe the subsurface geology of the area. Site-specific subsurface data are summarized in tables and profiles in this document. Uncertainty in data is mainly restricted to borehole information. Variations in sampling and drilling techniques present some correlation uncertainties across the sites. A greater degree of uncertainty exists on the new site because of restricted borehole coverage. There is some uncertainty to the location and orientation of elastic dikes across the sites.

  16. ATR-A1 irradiation experiment on vanadium alloys and low activation steels

    SciTech Connect

    Tasi, H.; Strain, R.V.; Gomes, I.; Hins, A.G.; Smith, D.L.

    1996-04-01

    To study the mechanical properties of vanadium alloys under neutron irradiation at low temperatures, an experiment was designed and constructed for irradiation in the Advanced Test Reactor (ATR). The experiment contained Charpy, tensile, compact tension, TEM, and creep specimens of vanadium alloys. It also contained limited low-activation ferritic steel specimens as part of the collaborative agreement with Monbusho of Japan. The design irradiation temperatures for the vanadium alloy specimens in the experiment are {approx}200 and 300{degrees}C, achieved with passive gap-gap sizing and fill gas blending. To mitigate vanadium-to-chromium transmutation from the thermal neutron flux, the test specimens are contained inside gadolinium flux filters. All specimens are lithium-bonded. The irradiation started in Cycle 108A (December 3, 1995) and is expected to have a duration of three ATR cycles and a peak influence of 4.4 dpa.

  17. Low cycle fatigue properties of a low activation ferritic steel (JLF-1) at room temperature

    NASA Astrophysics Data System (ADS)

    Nishimura, A.; Nagasaka, T.; Inoue, N.; Muroga, T.; Namba, C.

    2000-12-01

    To investigate fatigue properties of a low activation ferritic steel (9Cr-2W steel, JLF-1), low cycle fatigue tests were performed in air at room temperature under axial strain control for a complete push-pull condition. The strain rate was 0.4% s-1. Cyclic strain-hardening was observed within the initial 20 cycles, and then cyclic strain-softening occurred gradually until the final failure, though the plastic strain range did not change significantly. Tensile peak stresses in hysteresis curves measured at around half the number of cycles to failure depended on the total strain range. The drop in the peak stress by the cyclic strain-softening increased with decreasing total strain range. The regression curve of the total strain range against the fatigue life was formulated using the Manson-Coffin equation and the fatigue life of JLF-1 steel was compared with that of 8Cr-2W steel.

  18. Design requirements document for Project W-465, immobilized low-activity waste interim storage

    SciTech Connect

    Burbank, D.A.

    1998-05-19

    The scope of this Design Requirements Document (DRD) is to identify the functions and associated requirements that must be performed to accept, transport, handle, and store immobilized low-activity waste (ILAW) produced by the privatized Tank Waste Remediation System (TWRS) treatment contractors. The functional and performance requirements in this document provide the basis for the conceptual design of the TWRS ILAW Interim Storage facility project and provides traceability from the program level requirements to the project design activity. Technical and programmatic risk associated with the TWRS planning basis are discussed in the Tank Waste Remediation System Decisions and Risk Assessment (Johnson 1994). The design requirements provided in this document will be augmented by additional detailed design data documented by the project.

  19. Mechanical properties of low activating martensitic 8?10% CrWVTa steels of type OPTIFER

    NASA Astrophysics Data System (ADS)

    Schäfer, L.; Schirra, M.; Ehrlich, K.

    1996-10-01

    A series of low activating steels (OPTIFER-Ia, Ib, II, III and IV) has been developed as materials for the first wall and blanket structures of a future fusion device. The steels have been characterized by metallurgical examinations and by tests of the mechanical properties using tensile, impact bending and creep rupture tests. In comparison with conventional martensitic 9-12% CrMoVNb steels (e.g., MANET and P91 steels) a strong improvement of upper shelf impact energy and a remarkable shift to lower DBTT = -118°C was obtained, whereas other mechanical data are similar. Fracture toughness can be optimized by proper selection of austenitization temperature, quenching and tempering treatment with a preference of a lower austenitizing temperature.

  20. Charpy impact properties of low activation alloys for fusion applications after neutron irradiation

    NASA Astrophysics Data System (ADS)

    Rieth, M.; Dafferner, B.; Röhrig, H. D.

    1996-10-01

    The MANITU irradiation and fracture-toughness testing program although initially foreseen to clarify the early dose-saturation of ΔDBTT for commercial ferritic steels has been extended to include the medium temperature (≥ 250°C) irradiation hardening behaviour of promising low-activation alloys. The results after a first 0.8 dpa irradiation clearly show a much better behaviour of the new alloys in any respect (e.g. DBTT after irradiation always below +50°C for subsize specimens, for the ORNL steel even below -20°C). The complexity of temperature dependency is probably caused by the transition range in dose accumulation, and should therefore not be 'over-interpreted'.

  1. Research and development on the China low activation martensitic steel (CLAM)

    NASA Astrophysics Data System (ADS)

    Yu, Jinnan; Huang, Qunying; Wan, Farong

    2007-08-01

    Chinese low activation martensitic steel (CLAM) has been designed with improved composition, and its performance, such as tensile properties, ductile-brittle transition temperature (DBTT 41J), creep and thermal physical properties, has been determined. The interaction experiments between CLAM and plasma were carried out in the HT-7 tokamak facility and the activities, afterheat and gamma dose rate for CLAM as a function of cooling time (CT) were calculated to obtain the required control levels of impurities in CLAM. The insulator coatings on CLAM steel prepared by the CVD process at 700 °C and 740 °C have pure Al 2O 3 and Al 2O 3 with an oxygen deficiency layer on surface about 1 μm thick. The electrical resistivity of the coating reaches about 10 4 Ωm 2 on the surface.

  2. Calibration Of An Active Mammosite Using A Low Activity Sr-90 Radioactive Source

    NASA Astrophysics Data System (ADS)

    Winston, Jacquelyn

    2006-03-01

    The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillator fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Recent data were acquired at a local hospital to evaluate the possibility of measuring the dose distribution during breast Brachytherapy cancer treatments with this device. Since sub-millimeter accuracy in position is required, precision of the device relies on the accurate calibration of the scintillating fiber element. As part of a collaboration work, data were acquired for that purpose at Hampton University and subsequently analyzed at Morgan State University. An 8 mm diameter strontium-90 radioactive field source with a low activity of 25 μCi was used along with a dedicated LabView data acquisition system. We will discuss the data collected and address some of the features of this novel system.

  3. Calibration Of An Active Mammosite Using A Low Activity Sr-90 Radioactive Source

    NASA Astrophysics Data System (ADS)

    Winston, Jacquelyn

    2007-03-01

    The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillating fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Recent data were acquired at a local hospital to evaluate the possibility of measuring the dose distribution during breast Brachytherapy cancer treatments with this device. Since sub-millimeter accuracy in position is required, precision of the device relies on the accurate calibration of the scintillating fiber element. As part of a collaboration work, data were acquired for that purpose at Hampton University and subsequently analyzed at Morgan State University. An 8 mm diameter strontium-90 radioactive field source with a low activity of 25 μCi was used along with a dedicated LabView data acquisition system. We will discuss the data collected and address some of the features of this novel system.

  4. Status of ATR-A1 irradiation experiment on vanadium alloys and low-activation steels

    SciTech Connect

    Tsai, H.; Strain, R.V.; Gomes, I.; Smith, D.L.; Matsui, H.

    1996-10-01

    The ATR-A1 irradiation experiment was a collaborative U.S./Japan effort to study at low temperature the effects of neutron damage on vanadium alloys. The experiment also contained a limited quantity of low-activation ferritic steel specimens from Japan as part of the collaboration agreement. The irradiation started in the Advanced Test Reactor (ATR) on November 30, 1995, and ended as planned on May 5, 1996. Total exposure was 132.9 effective full power days (EFPDs) and estimated neutron damage in the vanadium was 4.7 dpa. The vehicle has been discharged from the ATR core and is scheduled to be disassembled in the next reporting period.

  5. Mars Aqueous Processing System

    NASA Technical Reports Server (NTRS)

    Berggren, Mark; Wilson, Cherie; Carrera, Stacy; Rose, Heather; Muscatello, Anthony; Kilgore, James; Zubrin, Robert

    2012-01-01

    The goal of the Mars Aqueous Processing System (MAPS) is to establish a flexible process that generates multiple products that are useful for human habitation. Selectively extracting useful components into an aqueous solution, and then sequentially recovering individual constituents, can obtain a suite of refined or semi-refined products. Similarities in the bulk composition (although not necessarily of the mineralogy) of Martian and Lunar soils potentially make MAPS widely applicable. Similar process steps can be conducted on both Mars and Lunar soils while tailoring the reaction extents and recoveries to the specifics of each location. The MAPS closed-loop process selectively extracts, and then recovers, constituents from soils using acids and bases. The emphasis on Mars involves the production of useful materials such as iron, silica, alumina, magnesia, and concrete with recovery of oxygen as a byproduct. On the Moon, similar chemistry is applied with emphasis on oxygen production. This innovation has been demonstrated to produce high-grade materials, such as metallic iron, aluminum oxide, magnesium oxide, and calcium oxide, from lunar and Martian soil simulants. Most of the target products exhibited purities of 80 to 90 percent or more, allowing direct use for many potential applications. Up to one-fourth of the feed soil mass was converted to metal, metal oxide, and oxygen products. The soil residue contained elevated silica content, allowing for potential additional refining and extraction for recovery of materials needed for photovoltaic, semiconductor, and glass applications. A high-grade iron oxide concentrate derived from lunar soil simulant was used to produce a metallic iron component using a novel, combined hydrogen reduction/metal sintering technique. The part was subsequently machined and found to be structurally sound. The behavior of the lunar-simulant-derived iron product was very similar to that produced using the same methods on a Michigan iron

  6. Consistent Selection towards Low Activity Phenotypes When Catchability Depends on Encounters among Human Predators and Fish

    PubMed Central

    Alós, Josep; Palmer, Miquel; Arlinghaus, Robert

    2012-01-01

    Together with life-history and underlying physiology, the behavioural variability among fish is one of the three main trait axes that determines the vulnerability to fishing. However, there are only a few studies that have systematically investigated the strength and direction of selection acting on behavioural traits. Using in situ fish behaviour revealed by telemetry techniques as input, we developed an individual-based model (IBM) that simulated the Lagrangian trajectory of prey (fish) moving within a confined home range (HR). Fishers exhibiting various prototypical fishing styles targeted these fish in the model. We initially hypothesised that more active and more explorative individuals would be systematically removed under all fished conditions, in turn creating negative selection differentials on low activity phenotypes and maybe on small HR. Our results partly supported these general predictions. Standardised selection differentials were, on average, more negative on HR than on activity. However, in many simulation runs, positive selection pressures on HR were also identified, which resulted from the stochastic properties of the fishes’ movement and its interaction with the human predator. In contrast, there was a consistent negative selection on activity under all types of fishing styles. Therefore, in situations where catchability depends on spatial encounters between human predators and fish, we would predict a consistent selection towards low activity phenotypes and have less faith in the direction of the selection on HR size. Our study is the first theoretical investigation on the direction of fishery-induced selection of behaviour using passive fishing gears. The few empirical studies where catchability of fish was measured in relation to passive fishing techniques, such as gill-nets, traps or recreational fishing, support our predictions that fish in highly exploited situations are, on average, characterised by low swimming activity, stemming, in

  7. MCNPX simulation of influence of cosmic rays on low-activity spectrometric measurements

    NASA Astrophysics Data System (ADS)

    Šolc, Jaroslav; Kovář, Petr; Dryák, Pavel

    2014-02-01

    Germanium gamma spectrometers are effective instruments for low-activity measurement of a mixture of radionuclides in environmental samples, food samples, in materials released from nuclear facilities to the environment, etc. In such measurements cosmic rays have a significant contribution to the background signal. A Monte Carlo code MCNPXTM was used to calculate coaxial high-purity germanium (HPGe) detector pulse-height spectra caused by cosmic rays penetrating through shielding made of concrete and lead. Simulations were compared to two different measurements, one performed inside a 10 cm thick lead shielding and another done inside a larger chamber made of low-activity concrete and with several ceiling thicknesses. In the first experiment, a discrepancy was found between simulated and measured spectra by up to the factor of 4 at 2.62 MeV and slowly decreasing to unity at 13 MeV. It is assumed that the discrepancy between the measured and simulated spectra is caused by the simplification of muon energy losses treatment resulting in the underestimation of count rate in simulated pulse-height spectrum. Good agreement was obtained between simulation and measurement of differences of detector count rates in 662 keV and 1332 keV energy windows inside a concrete chamber with varying ceiling thickness. It is assumed that due to lower effective Z of concrete, delta electron bremsstrahlung has lower yield and the muon radiation energy losses start to be important at higher energies than in lead. As a result, the total contribution of these effects to the outputs of MCNPXTM simulations of concrete chamber is not dominant in the investigated energy windows and the simulation results are in a close agreement with the measurement.

  8. Assessing low-activity faults for the seismic safety of dams

    SciTech Connect

    Page, W.D.; Savage, W.U.; McLaren, M.K.

    1995-12-31

    Dams have been a familiar construct in the northern Sierra Nevada range in California (north of the San Joaquin River) since the forty-niners and farmers diverted water to their gold mines and farms in the mid 19th century. Today, more than 370 dams dot the region from the Central Valley to the eastern escarpment. Fifty-five more dam streams on the eastern slope. The dams are of all types: 240 earth fill; 56 concrete gravity; 45 rock and earth fills; 35 rock fill; 14 concrete arch; 9 hydraulic fill; and 29 various other types. We use the northern Sierra Nevada to illustrate the assessment of low-activity faults for the seismic safety of dams. The approach, techniques, and methods of evaluation are applicable to other regions characterized by low seismicity and low-activity faults having long recurrence intervals. Even though several moderate earthquakes had shaken the Sierra Nevada since 1849 (for example, the 1875 magnitude 5.8 Honey Lake and the 1909 magnitudes 5 and 5.5 Downieville earthquakes), seismic analyses for dams in the area generally were not performed prior to the middle of this century. Following the 1971 magnitude 6.7 San Fernando earthquake, when the hydraulic-fill Lower Van Norman Dam in southern California narrowly escaped catastrophic failure, the California Division of Safety of Dams and the Federal Energy Regulatory Commission required seismic safety to be addressed with increasing rigor. In 1975, the magnitude 5.7 Oroville earthquake on the Cleveland Hill fault near Oroville Dam in the Sierra Nevada foothills, showed convincingly that earthquakes and surface faulting could occur within the range. Following this event, faults along the ancient Foothills fault system have been extensively investigated at dam sites.

  9. SU-E-J-144: Low Activity Studies of Carbon 11 Activation Via GATE Monte Carlo

    SciTech Connect

    Elmekawy, A; Ewell, L; Butuceanu, C; Qu, L

    2015-06-15

    Purpose: To investigate the behavior of a Monte Carlo simulation code with low levels of activity (∼1,000Bq). Such activity levels are expected from phantoms and patients activated via a proton therapy beam. Methods: Three different ranges for a therapeutic proton radiation beam were examined in a Monte Carlo simulation code: 13.5, 17.0 and 21.0cm. For each range, the decay of an equivalent length{sup 11}C source and additional sources of length plus or minus one cm was studied in a benchmark PET simulation for activities of 1000, 2000 and 3000Bq. The ranges were chosen to coincide with a previous activation study, and the activities were chosen to coincide with the approximate level of isotope creation expected in a phantom or patient irradiated by a therapeutic proton beam. The GATE 7.0 simulation was completed on a cluster node, running Scientific Linux Carbon 6 (Red Hat©). The resulting Monte Carlo data were investigated with the ROOT (CERN) analysis tool. The half-life of{sup 11}C was extracted via a histogram fit to the number of simulated PET events vs. time. Results: The average slope of the deviation of the extracted carbon half life from the expected/nominal value vs. activity showed a generally positive value. This was unexpected, as the deviation should, in principal, decrease with increased activity and lower statistical uncertainty. Conclusion: For activity levels on the order of 1,000Bq, the behavior of a benchmark PET test was somewhat unexpected. It is important to be aware of the limitations of low activity PET images, and low activity Monte Carlo simulations. This work was funded in part by the Philips corporation.

  10. Consistent selection towards low activity phenotypes when catchability depends on encounters among human predators and fish.

    PubMed

    Alós, Josep; Palmer, Miquel; Arlinghaus, Robert

    2012-01-01

    Together with life-history and underlying physiology, the behavioural variability among fish is one of the three main trait axes that determines the vulnerability to fishing. However, there are only a few studies that have systematically investigated the strength and direction of selection acting on behavioural traits. Using in situ fish behaviour revealed by telemetry techniques as input, we developed an individual-based model (IBM) that simulated the Lagrangian trajectory of prey (fish) moving within a confined home range (HR). Fishers exhibiting various prototypical fishing styles targeted these fish in the model. We initially hypothesised that more active and more explorative individuals would be systematically removed under all fished conditions, in turn creating negative selection differentials on low activity phenotypes and maybe on small HR. Our results partly supported these general predictions. Standardised selection differentials were, on average, more negative on HR than on activity. However, in many simulation runs, positive selection pressures on HR were also identified, which resulted from the stochastic properties of the fishes' movement and its interaction with the human predator. In contrast, there was a consistent negative selection on activity under all types of fishing styles. Therefore, in situations where catchability depends on spatial encounters between human predators and fish, we would predict a consistent selection towards low activity phenotypes and have less faith in the direction of the selection on HR size. Our study is the first theoretical investigation on the direction of fishery-induced selection of behaviour using passive fishing gears. The few empirical studies where catchability of fish was measured in relation to passive fishing techniques, such as gill-nets, traps or recreational fishing, support our predictions that fish in highly exploited situations are, on average, characterised by low swimming activity, stemming, in

  11. Mechanical property changes of low activation ferritic/martensitic steels after neutron irradiation

    NASA Astrophysics Data System (ADS)

    Kohno, Y.; Kohyama, A.; Hirose, T.; Hamilton, M. L.; Narui, M.

    Mechanical property changes of Fe- XCr-2W-0.2V,Ta ( X: 2.25-12) low activation ferritic/martensitic steels including Japanese Low Activation Ferritic/martensitic (JLF) steels and F82H after neutron irradiation were investigated with emphasis on Charpy impact property, tensile property and irradiation creep properties. Dose dependence of ductile-to-brittle transition temperature (DBTT) in JLF-1 (9Cr steel) irradiated at 646-700 K increased with irradiation up to 20 dpa and then decreased with further irradiation showing highest DBTT of 260 K at 20 dpa. F82H showed similar dose dependence in DBTT to JLF-1 with higher transition temperature than that of JLF-1 at the same displacement damage. Yield strength in JLF steels and F82H showed similar dose dependence to that of DBTT. Yield strength increased with irradiation up to 15-20 dpa and then decreased to saturate above about 40 dpa. Irradiation hardening in 7-9%Cr steels (JLF-1, JLF-3, F82H) were observed to be smaller than those in steels with 2.25%Cr (JLF-4) or 12%Cr (JLF-5). Dependences of creep strain on applied hoop stress and neutron fluence were measured to be 1.5 and 1, respectively. Temperature dependence of creep coefficient showed a maximum at about 700 K which was caused by irradiation induced void formation or irradiation enhanced creep deformation. Creep coefficient of F82H was larger than those of JLF steels above 750 K. This was considered to be caused by the differences in N and Ta concentration between F82H and JLF steels.

  12. Data Packages for the Hanford Immobilized Low Activity Tank Waste Performance Assessment 2001 Version [SEC 1 THRU 5

    SciTech Connect

    MANN, F.M.

    2000-03-02

    Data package supporting the 2001 Immobilized Low-Activity Waste Performance Analysis. Geology, hydrology, geochemistry, facility, waste form, and dosimetry data based on recent investigation are provided. Verification and benchmarking packages for selected software codes are provided.

  13. Sampling and analysis plan for the preoperational environmental survey for the immobilized low activity waste (ILAW) project W-465

    SciTech Connect

    Mitchell, R.M.

    1998-09-28

    This document provides a detailed description of the Sampling and Analysis Plan for the Preoperational Survey to be conducted at the Immobilized Low Activity Waste (ILAW) Project Site in the 200 East Area.

  14. Annual summary of Immobilized Low-Activity Waste (ILAW) Performance Assessment for 2003 Incorporating the Integrated Disposal Facility Concept

    SciTech Connect

    MANN, F M

    2003-09-01

    To Erik Olds 09/30/03 - An annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) is necessary in each year in which a full performance assessment is not issued.

  15. Aqueous photolysis of niclosamide

    USGS Publications Warehouse

    Graebing, P.W.; Chib, J.S.; Hubert, T.D.; Gingerich, W.H.

    2004-01-01

    The photodegradation of [14C]niclosamide was studied in sterile, pH 5, 7, and 9 buffered aqueous solutions under artificial sunlight at 25.0 A? 1.0 A?C. Photolysis in pH 5 buffer is 4.3 times faster than in pH 9 buffer and 1.5 times faster than in pH 7 buffer. In the dark controls, niclosamide degraded only in the pH 5 buffer. After 360 h of continuous irradiation in pH 9 buffer, the chromatographic pattern of the degradates was the same regardless of which ring contained the radiolabel. An HPLC method was developed that confirmed these degradates to be carbon dioxide and two- and four-carbon aliphatic acids formed by cleavage of both aromatic rings. Carbon dioxide was the major degradate, comprising 40% of the initial radioactivity in the 360 h samples from both labels. The other degradates formed were oxalic acid, maleic acid, glyoxylic acid, and glyoxal. In addition, in the chloronitroaniline-labeled irradiated test solution, 2-chloro-4-nitroaniline was observed and identified after 48 h of irradiation but was not detected thereafter. No other aromatic compounds were isolated or observed in either labeled test system.

  16. Aqueous chlorination of resorcinol

    USGS Publications Warehouse

    Heasley, V.L.; Burns, M.D.; Kemalyan, N.A.; Mckee, T.C.; Schroeter, H.; Teegarden, B.R.; Whitney, S.E.; Wershaw, R. L.

    1989-01-01

    An investigation of the aqueous chlorination (NaOCl) of resorcinol is reported. The following intermediates were detected in moderate to high yield at different pH values and varying percentages of chlorination: 2-chloro-, 4-chloro-, 2,4-dichloro-, 4,6-dichloro- and 2,4,6-trichlororesorcinol. Only trace amounts of the intermediates were detected when the chlorination was conducted in the presence of phosphate buffer. This result has significant implications since resorcinol in phosphate buffer has been used as a model compound in several recent studies on the formation of chlorinated hydrocarbons during chlorination of drinking water. Relative rates of chlorination were determined for resorcinol and several of the chlorinated resorcinols. Resorcinol was found to chlorinate only three times faster than 2,4,6-trichlororesorcinol. The structure 2,4,6-trichlororesorcinol was established as a monohydrate even after sublimation. A tetrachloro or pentachloro intermediate was not detected, suggesting that the ring-opening step of such an intermediate must be rapid. ?? 1989.

  17. Virtual Laboratories

    NASA Astrophysics Data System (ADS)

    Hut, P.

    At the frontier of most areas in science, computer simulations playa central role. The traditional division of natural science into experimental and theoretical investigations is now completely outdated. Instead, theory, simulation, and experimentation form three equally essential aspects, each with its own unique flavor and challenges. Yet, education in computational science is still lagging far behind, and the number of text books in this area is minuscule compared to the many text books on theoretical and experimental science. As a result, many researchers still carry out simulations in a haphazard way, without properly setting up the computational equivalent of a well equipped laboratory. The art of creating such a virtual laboratory, while providing proper extensibility and documentation, is still in its infancy. A new approach is described here, Open Knowledge, as an extension of the notion of Open Source software. Besides open source code, manuals, and primers, an open knowledge project provides simulated dialogues between code developers, thus sharing not only the code, but also the motivations behind the code.

  18. Aqueous Corrosion Rates for Waste Package Materials

    SciTech Connect

    S. Arthur

    2004-10-08

    The purpose of this analysis, as directed by ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]), is to compile applicable corrosion data from the literature (journal articles, engineering documents, materials handbooks, or standards, and national laboratory reports), evaluate the quality of these data, and use these to perform statistical analyses and distributions for aqueous corrosion rates of waste package materials. The purpose of this report is not to describe the performance of engineered barriers for the TSPA-LA. Instead, the analysis provides simple statistics on aqueous corrosion rates of steels and alloys. These rates are limited by various aqueous parameters such as temperature (up to 100 C), water type (i.e., fresh versus saline), and pH. Corrosion data of materials at pH extremes (below 4 and above 9) are not included in this analysis, as materials commonly display different corrosion behaviors under these conditions. The exception is highly corrosion-resistant materials (Inconel Alloys) for which rate data from corrosion tests at a pH of approximately 3 were included. The waste package materials investigated are those from the long and short 5-DHLW waste packages, 2-MCO/2-DHLW waste package, and the 21-PWR commercial waste package. This analysis also contains rate data for some of the materials present inside the fuel canisters for the following fuel types: U-Mo (Fermi U-10%Mo), MOX (FFTF), Thorium Carbide and Th/U Carbide (Fort Saint Vrain [FSVR]), Th/U Oxide (Shippingport LWBR), U-metal (N Reactor), Intact U-Oxide (Shippingport PWR, Commercial), aluminum-based, and U-Zr-H (TRIGA). Analysis of corrosion rates for Alloy 22, spent nuclear fuel, defense high level waste (DHLW) glass, and Titanium Grade 7 can be found in other analysis or model reports.

  19. CAPSULE REPORT: AQUEOUS MERCURY TREATMENT

    EPA Science Inventory

    This report describes established technologies and identifies evolving methods for treating aqueous mercury. The information provided encompasses full-, pilot- and bench-scale treatment results as presented in the technical literature. The report describes alternative technologi...

  20. CAPSULE REPORT: AQUEOUS MERCURY TREATMENT

    EPA Science Inventory

    This report describes established technologies and identifies evolving methods for treating aqueous mercury. The information provided encompasses full-, pilot- and bench-scale treatment results as presented in the technical literature. The report describes alternative technologi...

  1. An investigation for unexpected high yield of peroxides from isoprene through aqueous phase ozonolysis

    NASA Astrophysics Data System (ADS)

    Wang, H.; Chen, Z.; Hua, W.; Jie, C.

    2007-12-01

    It has recently become evident that isoprene, the atmosphere's most abundant non-methane hydrocarbon, and its oxidation products can considerably result in formation of secondary organic aerosols (SOA) through the acid- catalyzed aqueous phase reaction with hydrogen peroxide. However, the peroxide source in the atmospheric aqueous process is unclear. The present study revealed a potentially important route to the formation of aqueous peroxides, including hydrogen peroxide and hydroxylmethyl hydroperoxide, from the aqueous phase ozonolysis of isoprene. In this study, the atmospheric aqueous phase ozonolysis of isoprene at different pHs and temperatures were studied with the method of laboratory simulation. The major products, including peroxides and carbonyl compounds, were well-characterized, with a measured carbon balance approaching 100%, and the detailed reaction mechanisms were proposed. Most strikingly, peroxides have been found in the aqueous phase ozonolysis of isoprene with unexpected high yields. Considering the huge amount of isoprene in the atmosphere, we suggest that the aqueous phase ozonolysis of isoprene and its first-generation oxidation products may contribute a considerable and even the main source of oxidants to the atmospheric aqueous phase. This means that isoprene and its oxidation products can be transformed into SOA by peroxides provided from their aqueous phase ozonolysis reactions, even if there is no other peroxide source.

  2. Coal desulfurization by aqueous chlorination

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Vasilakos, N.; Corcoran, W. H.; Grohmann, K.; Rohatgi, N. K. (Inventor)

    1982-01-01

    A method of desulfurizing coal is described in which chlorine gas is bubbled through an aqueous slurry of coal at low temperature below 130 degrees C., and at ambient pressure. Chlorinolysis converts both inorganic and organic sulfur components of coal into water soluble compounds which enter the aqueous suspending media. The media is separated after chlorinolysis and the coal dechlorinated at a temperature of from 300 C to 500 C to form a non-caking, low-sulfur coal product.

  3. Simulator for SUPO, a Benchmark Aqueous Homogeneous Reactor (AHR)

    SciTech Connect

    Klein, Steven Karl; Determan, John C.

    2015-10-14

    A simulator has been developed for SUPO (Super Power) an aqueous homogeneous reactor (AHR) that operated at Los Alamos National Laboratory (LANL) from 1951 to 1974. During that period SUPO accumulated approximately 600,000 kWh of operation. It is considered the benchmark for steady-state operation of an AHR. The SUPO simulator was developed using the process that resulted in a simulator for an accelerator-driven subcritical system, which has been previously reported.

  4. A critique of homogeneous freezing measurements of aqueous sulfuric acid

    NASA Astrophysics Data System (ADS)

    Alofs, Darryl J.; Vandike, John L.

    2000-08-01

    Two laboratory measurements of homogeneous freezing of aqueous sulfuric acid particles are critiqued: The first by Bertram et al., 1996, J. Phys. Chem., vol. 100, pp. 2376-2383: the second by Koop et al., 1998, J. Phys. Chem. A, vol. 102, pp. 8924-8931. Calculations for a proposed experimental artifact are inconclusive for Bertram et al. A proposed artifact for Koop et al. is shown to be insignificant.

  5. Corrosion problems with aqueous coolants, final report

    SciTech Connect

    Diegle, R B; Beavers, J A; Clifford, J E

    1980-04-11

    The results of a one year program to characterize corrosion of solar collector alloys in aqueous heat-transfer media are summarized. The program involved a literature review and a laboratory investigation of corrosion in uninhibited solutions. It consisted of three separate tasks, as follows: review of the state-of-the-art of solar collector corrosion processes; study of corrosion in multimetallic systems; and determination of interaction between different waters and chemical antifreeze additives. Task 1 involved a comprehensive review of published literature concerning corrosion under solar collector operating conditions. The reivew also incorporated data from related technologies, specifically, from research performed on automotive cooling systems, cooling towers, and heat exchangers. Task 2 consisted of determining the corrosion behavior of candidate alloys of construction for solar collectors in different types of aqueous coolants containing various concentrations of corrosive ionic species. Task 3 involved measuring the degradation rates of glycol-based heat-transfer media, and also evaluating the effects of degradation on the corrosion behavior of metallic collector materials.

  6. Laboratory investigations

    NASA Technical Reports Server (NTRS)

    Russell, Ray W.

    1988-01-01

    Laboratory studies related to cometary grains and the nuclei of comets can be broken down into three areas which relate to understanding the spectral properties, the formation mechanisms, and the evolution of grains and nuclei: (1) Spectral studies to be used in the interpretation of cometary spectra; (2) Sample preparation experiments which may shed light on the physical nature and history of cometary grains and nuclei by exploring the effects on grain emissivities resulting from the ways in which the samples are created; and (3) Grain processing experiments which should provide insight on the interaction of cometary grains with the environment in the immediate vicinity of the cometary nucleus as the comet travels from the Oort cloud through perihelion, and perhaps even suggestions regarding the relationship between interstellar grains and cometary matter. A summary is presented with a different view of lab experiments than is found in the literature, concentrating on measurement techniques and sample preparations especially relevant to cometary dust.

  7. All-aqueous multiphase microfluidics

    PubMed Central

    Song, Yang; Sauret, Alban; Cheung Shum, Ho

    2013-01-01

    Immiscible aqueous phases, formed by dissolving incompatible solutes in water, have been used in green chemical synthesis, molecular extraction and mimicking of cellular cytoplasm. Recently, a microfluidic approach has been introduced to generate all-aqueous emulsions and jets based on these immiscible aqueous phases; due to their biocompatibility, these all-aqueous structures have shown great promises as templates for fabricating biomaterials. The physico-chemical nature of interfaces between two immiscible aqueous phases leads to unique interfacial properties, such as an ultra-low interfacial tension. Strategies to manipulate components and direct their assembly at these interfaces needs to be explored. In this paper, we review progress on the topic over the past few years, with a focus on the fabrication and stabilization of all-aqueous structures in a multiphase microfluidic platform. We also discuss future efforts needed from the perspectives of fluidic physics, materials engineering, and biology for fulfilling potential applications ranging from materials fabrication to biomedical engineering. PMID:24454609

  8. Photochemistry of aqueous pyruvic acid

    PubMed Central

    Griffith, Elizabeth C.; Carpenter, Barry K.; Shoemaker, Richard K.; Vaida, Veronica

    2013-01-01

    The study of organic chemistry in atmospheric aerosols and cloud formation is of interest in predictions of air quality and climate change. It is now known that aqueous phase chemistry is important in the formation of secondary organic aerosols. Here, the photoreactivity of pyruvic acid (PA; CH3COCOOH) is investigated in aqueous environments characteristic of atmospheric aerosols. PA is currently used as a proxy for α-dicarbonyls in atmospheric models and is abundant in both the gas phase and the aqueous phase (atmospheric aerosols, fog, and clouds) in the atmosphere. The photoreactivity of PA in these phases, however, is very different, thus prompting the need for a mechanistic understanding of its reactivity in different environments. Although the decarboxylation of aqueous phase PA through UV excitation has been studied for many years, its mechanism and products remain controversial. In this work, photolysis of aqueous PA is shown to produce acetoin (CH3CHOHCOCH3), lactic acid (CH3CHOHCOOH), acetic acid (CH3COOH), and oligomers, illustrating the progression from a three-carbon molecule to four-carbon and even six-carbon molecules through direct photolysis. These products are detected using vibrational and electronic spectroscopy, NMR, and MS, and a reaction mechanism is presented accounting for all products detected. The relevance of sunlight-initiated PA chemistry in aqueous environments is then discussed in the context of processes occurring on atmospheric aerosols. PMID:23821751

  9. Photochemistry of aqueous pyruvic acid.

    PubMed

    Griffith, Elizabeth C; Carpenter, Barry K; Shoemaker, Richard K; Vaida, Veronica

    2013-07-16

    The study of organic chemistry in atmospheric aerosols and cloud formation is of interest in predictions of air quality and climate change. It is now known that aqueous phase chemistry is important in the formation of secondary organic aerosols. Here, the photoreactivity of pyruvic acid (PA; CH3COCOOH) is investigated in aqueous environments characteristic of atmospheric aerosols. PA is currently used as a proxy for α-dicarbonyls in atmospheric models and is abundant in both the gas phase and the aqueous phase (atmospheric aerosols, fog, and clouds) in the atmosphere. The photoreactivity of PA in these phases, however, is very different, thus prompting the need for a mechanistic understanding of its reactivity in different environments. Although the decarboxylation of aqueous phase PA through UV excitation has been studied for many years, its mechanism and products remain controversial. In this work, photolysis of aqueous PA is shown to produce acetoin (CH3CHOHCOCH3), lactic acid (CH3CHOHCOOH), acetic acid (CH3COOH), and oligomers, illustrating the progression from a three-carbon molecule to four-carbon and even six-carbon molecules through direct photolysis. These products are detected using vibrational and electronic spectroscopy, NMR, and MS, and a reaction mechanism is presented accounting for all products detected. The relevance of sunlight-initiated PA chemistry in aqueous environments is then discussed in the context of processes occurring on atmospheric aerosols.

  10. Ultrasonic frequency selection for aqueous fine cleaning

    NASA Technical Reports Server (NTRS)

    Becker, Joann F.

    1995-01-01

    A study was conducted to evaluate ultrasonic cleaning systems for precision cleaning effectiveness for oxygen service hardware. This evaluation was specific for Rocketdyne Division of Rockwell Aerospace alloys and machining soils. Machining lubricants and hydraulic fluid were applied as soils to standardized complex test specimens designed to simulate typical hardware. The study consisted of tests which included 20, 25, 30, 40, 50, and 65 kHz ultrasonic cleaning systems. Two size categories of cleaning systems were evaluated, 3- to 10-gal laboratory size tanks and 35- to 320-gal industrial size tanks. The system properties of cavitation, frequency vs. cleaning effectiveness, the two types of transducers, and the power level of the system vs. size of the cleaning tank were investigated. The data obtained from this study was used to select the ultrasonic tanks for the aqueous fine clean facility installed at Rocketdyne.

  11. Ultrasonic frequency selection for aqueous fine cleaning

    NASA Technical Reports Server (NTRS)

    Becker, Joann F.

    1994-01-01

    A study was conducted to evaluate ultrasonic cleaning systems for precision cleaning effectiveness for oxygen service hardware. This evaluation was specific for Rocketdyne Div. of Rockwell Aerospace alloys and machining soils. Machining lubricants and hydraulic fluid were applied as soils to standardized complex test specimens designed to simulate typical hardware. The study consisted of tests which included 20, 25, 30, 40, 50, and 65 kHz ultrasonic cleaning systems. Two size categories of cleaning systems were evaluated, 3- to 10-gal laboratory size tanks and 35- to 320-gal industrial size tanks. The system properties of cavitation; frequency vs. cleaning effectiveness; the two types of transducers; and the power level of the system vs. size of the cleaning tank were investigated. The data obtained from this study was used to select the ultrasonic tanks for the aqueous fine clean facility installed at Rocketdyne.

  12. Ultrasonic frequency selection for aqueous fine cleaning

    NASA Astrophysics Data System (ADS)

    Becker, Joann F.

    1995-03-01

    A study was conducted to evaluate ultrasonic cleaning systems for precision cleaning effectiveness for oxygen service hardware. This evaluation was specific for Rocketdyne Division of Rockwell Aerospace alloys and machining soils. Machining lubricants and hydraulic fluid were applied as soils to standardized complex test specimens designed to simulate typical hardware. The study consisted of tests which included 20, 25, 30, 40, 50, and 65 kHz ultrasonic cleaning systems. Two size categories of cleaning systems were evaluated, 3- to 10-gal laboratory size tanks and 35- to 320-gal industrial size tanks. The system properties of cavitation, frequency vs. cleaning effectiveness, the two types of transducers, and the power level of the system vs. size of the cleaning tank were investigated. The data obtained from this study was used to select the ultrasonic tanks for the aqueous fine clean facility installed at Rocketdyne.

  13. Reduction of noise in the beta camera for low activity applications

    NASA Astrophysics Data System (ADS)

    Ljunggren, K.; Strand, S.-E.

    1994-08-01

    The 'Beta-camera' used in the past in our laboratory for imaging of biomedical samples, has a noise level of about 50 counts per second. It is desirable to reduce this noise, in order to improve the detectability in the biological samples. Accordingly in this paper, we report on a coincidence technique that reduces the noise level to almost zero.

  14. TWRS Retrieval and Storage Mission and Immobilized Low Activity Waste (ILAW) Disposal Plan

    SciTech Connect

    BURBANK, D.A.

    1999-09-01

    This project plan has a twofold purpose. First, it provides a waste stream project plan specific to the River Protection Project (RPP) (formerly the Tank Waste Remediation System [TWRS] Project) Immobilized Low-Activity Waste (LAW) Disposal Subproject for the Washington State Department of Ecology (Ecology) that meets the requirements of Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-90-01 (Ecology et al. 1994) and is consistent with the project plan content guidelines found in Section 11.5 of the Tri-Party Agreement action plan (Ecology et al. 1998). Second, it provides an upper tier document that can be used as the basis for future subproject line-item construction management plans. The planning elements for the construction management plans are derived from applicable U.S. Department of Energy (DOE) planning guidance documents (DOE Orders 4700.1 [DOE 1992] and 430.1 [DOE 1995a]). The format and content of this project plan are designed to accommodate the requirements mentioned by the Tri-Party Agreement and the DOE orders. A cross-check matrix is provided in Appendix A to explain where in the plan project planning elements required by Section 11.5 of the Tri-Party Agreement are addressed.

  15. Crystallization of rhenium salts in a simulated low-activity waste borosilicate glass

    SciTech Connect

    Riley, Brian J.; McCloy, John S.; Goel, Ashutosh; Liezers, Martin; Schweiger, Michael J.; Liu, Juan; Rodriguez, Carmen P.; Kim, Dong-Sang

    2013-04-01

    This study presents a new method for looking at the solubility of volatile species in simulated low-activity waste glass. The present study looking at rhenium salts is also applicable to real applications involving radioactive technetium salts. In this synthesis method, oxide glass powder is mixed with the volatiles species, vacuum-sealed in a fused quartz ampoule, and then heat-treated under vacuum in a furnace. This technique restricts the volatile species to the headspace above the melt but still within the sealed ampoule, thus maximizing the volatile concentration in contact with the glass. Various techniques were used to measure the solubility of rhenium in glass and include energy dispersive spectroscopy, wavelength dispersive spectroscopy, laser ablation inductively-coupled plasma mass spectroscopy, and inductively-coupled plasma optical emission spectroscopy. The Re-solubility in this glass was determined to be ~3004 parts per million Re atoms. Above this concentration, the salts separated out of the melt as inclusions and as a low viscosity molten salt phase on top of the melt observed during and after cooling. This salt phase was analyzed with X-ray diffraction, scanning electron microscopy as well as some of the other aforementioned techniques and identified to be composed of alkali perrhenate and alkali sulfate.

  16. Iodine solubility in a low-activity waste borosilicate glass at 1000°C

    DOE PAGES

    Riley, Brian J.; Schweiger, Michael J.; Kim, Dong-Sang; ...

    2014-04-30

    The purpose of this study was to determine the solubility of iodine in a low-activity waste borosilicate glass when heated inside an evacuated and sealed fused quartz ampoule. The iodine was added to glass frit as KI in quantities of 100–24000 ppm iodine (by mass), each mixture was added to an ampoule, the ampoules were heated at 1000 °C for 2h, and then air quenched. In samples with ≥12000 ppm iodine, low viscosity salt phases were observed on the surface of the melts during cooling that solidified into a white coating upon cooling. These salts were identified as mixtures ofmore » KI, NaI, and Na2SO4 with X-ray diffraction (XRD). The iodine concentrations in glass specimens were analyzed with inductively-coupled plasma mass spectrometry and the overall iodine solubility was determined to be 10000 ppm by mass. Several crystalline inclusions of iodine sodalite, Na8(AlSiO4)6I2, were observed in the 24000 ppm specimen as determined by micro-XRD and wavelength dispersive spectroscopy.« less

  17. Scenarios for the Hanford immobilized Low-Activity waste (ILAW) performance assessment

    SciTech Connect

    MANN, F.M.

    1999-09-09

    The purpose of the next version of the Hanford Immobilized Low-Activity Tank Waste (ILAW) Performance Assessment (ILAW PA) is to provide an updated estimate of the long-term human health and environmental impact of the disposal of ILAW and to compare these estimates against performance objectives displayed in Tables 1,2, and 3 (Mann 1999a). Such a radiological performance assessment is required by U.S. Department of Energy (DOE) Orders on radioactive waste management (DOE 1988a and DOE 1999a). This document defines the scenarios that will be used for the next update of the PA that is scheduled to be issued in 2001. Since the previous performance assessment (Mann 1998) was issued, considerable additional data on waste form behavior and site-specific soil geotechnical properties have been collected. In addition, the 2001 ILAW PA will benefit from improved computer models and the experience gained from the previous performance assessment. However, the scenarios (that is, the features, events, and processes analyzed in the Performance assessment) for the next PA are very similar to the ones in the 1998 PA.

  18. Assessment of plasma parameters for the low activation phase of ITER operation

    NASA Astrophysics Data System (ADS)

    Polevoi, A. R.; Campbell, D. J.; Chuyanov, V. A.; Houlberg, W.; Ivanov, A. A.; Kukushkin, A. S.; Lamalle, P.; Loarte, A.; Mukhovatov, V. S.; Oikawa, T.

    2013-12-01

    An assessment of ITER plasma parameters is carried out for the low activation phase that is required for commissioning the basic ITER systems including plasma control, heating and current drive. Such an operation is analysed for hydrogen, helium and deuterium plasmas for full field and current, as well as with magnetic field and plasma current reduced to half of their design values, B0 = 2.65 T, Ip = 7.5 MA. Both hydrogen and deuterium neutral beam injection (NBI) are considered. We assess the possible domain for safe operation, and the possible target plasmas for commissioning the NBI, electron cyclotron heating (ECH) and ion cyclotron heating (ICH) systems, taking into account the constraints imposed by NB shine-through loss, Greenwald limit and access to H-mode operation. Simulations with the Automated System for Transport Analysis (ASTRA) show that for 33 MW of NBI with 20 MW of ECH, H-mode access is marginal for hydrogen plasmas. Good H-mode confinement, expected at PNB + PEC + PIC > 1.5 PL-H, is more likely for the helium and deuterium cases. It is found that plasma parameters, such as normalized beta, plasma density and current flat-top duration, for full power/half field/half current operation can be similar to those required for the DT long pulse operation. Preliminary assessment is also made of the maximum of tritium and neutron yield achievable in a single shot at the deuterium phase of ITER operation.

  19. Interdiffusion behaviors of iron aluminide coatings on China low activation martensitic steel

    NASA Astrophysics Data System (ADS)

    Zhu, X. X.; Yang, H. G.; Yuan, X. M.; Zhao, W. W.; Zhan, Q.

    2014-12-01

    The iron aluminide coating on China Low Activation Martensitic (CLAM) steel was prepared by pack cementation and subsequent heat treatment. A surface Fe2Al5 layer was formed on CLAM substrate by pack cementation process with Fe2Al5 donor powder and NH4Cl activator. Diffusion heat treatment was performed in order to allow the phase transformation from Fe2Al5 to a phase with lower aluminum content. Morphology and composition of the coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), glow discharge optical emission spectroscopy (GDOES) and X-ray diffraction (XRD). There is a need to study the interdiffusion behaviors in these Al containing systems, as a basis for controlling the formation and subsequent degradation of the coating. In this paper, a predictive model was developed to describe the phase transformation of Fe2Al5 as a function of processing parameters. The Wagner's equation was used to calculate the interdiffusion coefficients based on the analysis of the Al concentration profiles. The results showed that the interdiffusion coefficients in the FeAl and α-Fe(Al) phase strongly depends on Al content and showed a maximum at about 28 at.% Al.

  20. Iodine Solubility in Low-Activity Waste Borosilicate Glass at 1000 °C

    SciTech Connect

    Riley, Brian J.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; Williams, Benjamin D.; Iovin, Cristian; Rodriguez, Carmen P.; Overman, Nicole R.; Bowden, Mark E.; Dixon, Derek R.; Crum, Jarrod V.; Mccloy, John S.; Kruger, Albert A.

    2014-04-30

    The purpose of this study was to determine the solubility of iodine in a low-activity waste borosilicate glass when heated inside an evacuated and sealed fused quartz ampoule. The iodine was added to glass frit as KI in quantities of 100–24000 ppm iodine (by mass), each mixture was added to an ampoule, the ampoule was heated at 1000 °C for 2 h and then air quenched. In samples with ≥12000 ppm iodine, low viscosity salt phases were observed on the surface of the melts during cooling that solidified into a white coating upon cooling. These salts were identified as mixtures of KI, NaI, and Na2SO4 with X-ray diffraction (XRD). The iodine concentrations in glass specimens were analyzed with inductively-coupled plasma mass spectrometry and the overall iodine solubility was determined to be 10000 ppm by mass. Several crystalline inclusions of iodine sodalite, Na8(AlSiO4)6I2, were observed in the 24000 ppm specimen and were verified with micro-XRD and wavelength dispersive spectroscopy.

  1. Lessons Learned From Reactive Transport Modeling of a Low-Activity Waste Glass Disposal System

    SciTech Connect

    Bacon, Diana H.; McGrail, B PETER.

    2003-04-01

    A set of reactive chemical transport calculations was conducted with the Subsurface Transport Over Reactive Multi-phases (STORM) code to evaluate the long-term performance of a representative low-activity waste glass in a shallow subsurface disposal system located on the Hanford Site. Two different trench designs were considered, one with four rows of small waste packages, the other with three layers of larger waste packages. One-dimensional simulations were carried out to 20,000 years, whereas two-dimensional simulations could only be carried out for several hundred years due to constraints on computational time. Both the 1-D and 2-D simulations predict that the Technetium release rate from the waste packages will be lower for the new trench design at later times. Because the glass corrosion rate is significantly higher at the backfill/glass interfaces, having less interfacial area in the new trench design offsets the effect of the slightly higher pH relative to the old trench design. In the two-dimensional simulations, water can flow around the waste packages, which causes a decrease in the water flux through the waste packages and lower release rates than predicted in the 1-D simulations. This result reinforces the importance of performing multi-dimensional waste form release simulations.

  2. Redox-dependent solubility of technetium in low activity waste glass

    NASA Astrophysics Data System (ADS)

    Soderquist, Chuck Z.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; McCloy, John S.

    2014-06-01

    The solubility of technetium was measured in a Hanford low activity waste (LAW) glass simulant, to investigate the extent that technetium solubility controls the incorporation of technetium into LAW glass. A series of LAW glass samples, spiked with 500-6000 ppm of Tc as potassium pertechnetate, were melted at 1000 °C in sealed fused quartz ampoules. Technetium solubility was determined in the quenched bulk glass to be 2000-2800 ppm, with slightly reducing conditions due to choice of milling media resulting in reductant contamination and higher solubility. The chemical form of technetium obtained by X-ray absorption near edge spectroscopy is mainly isolated, octahedrally-coordinated Tc(IV), with a minority of Tc(VII) in some glasses and TcO2 in two glasses. The concentration and speciation of technetium depends on glass redox and amount of technetium added. Salts formed at the top of higher technetium loaded glasses during the melt. The results of this study show that technetium solubility should not be a factor in technetium retention during melting of Hanford LAW glass.

  3. Iodine solubility in a low-activity waste borosilicate glass at 1000°C

    SciTech Connect

    Riley, Brian J.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; Williams, Benjamin D.; Iovin, Cristian; Rodriguez, Carmen P.; Overman, Nicole R.; Bowden, Mark E.; Dixon, Derek R.; Crum, Jarrod V.; McCloy, John S.; Kruger, Albert A.

    2014-04-30

    The purpose of this study was to determine the solubility of iodine in a low-activity waste borosilicate glass when heated inside an evacuated and sealed fused quartz ampoule. The iodine was added to glass frit as KI in quantities of 100–24000 ppm iodine (by mass), each mixture was added to an ampoule, the ampoules were heated at 1000 °C for 2h, and then air quenched. In samples with ≥12000 ppm iodine, low viscosity salt phases were observed on the surface of the melts during cooling that solidified into a white coating upon cooling. These salts were identified as mixtures of KI, NaI, and Na2SO4 with X-ray diffraction (XRD). The iodine concentrations in glass specimens were analyzed with inductively-coupled plasma mass spectrometry and the overall iodine solubility was determined to be 10000 ppm by mass. Several crystalline inclusions of iodine sodalite, Na8(AlSiO4)6I2, were observed in the 24000 ppm specimen as determined by micro-XRD and wavelength dispersive spectroscopy.

  4. Studies on A-TIG welding of Low Activation Ferritic/Martensitic (LAFM) steel

    NASA Astrophysics Data System (ADS)

    Vasantharaja, P.; Vasudevan, M.

    2012-02-01

    Low Activation Ferritic-Martensitic steels (LAFM) are chosen as the candidate material for structural components in fusion reactors. The structural components are generally fabricated by welding processes. Activated Tungsten Inert Gas (A-TIG) welding is an emerging process for welding of thicker components. In the present work, attempt was made to develop A-TIG welding technology for LAFM steel plates of 10 mm thick. Activated flux was developed for LAFM steel by carrying out various bead-on-plate TIG welds without flux and with flux. The optimum flux was identified as one which gave maximum depth of penetration at minimum heat input values. With the optimized flux composition, LAFM steel plate of 10 mm thickness was welded in square butt weld joint configuration using double side welding technique. Optical and Scanning Electron Microscopy was used for characterizing the microstructures. Microhardness measurements were made across the weld cross section for as welded and post weld heat treated samples. Tensile and impact toughness properties were determined. The mechanical properties values obtained in A-TIG weld joint were comparable to that obtained in weld joints of LAFM steel made by Electron beam welding process.

  5. Groundwater Flow and Transport Calculations Supporting the Immobilized Low-Activity Waste Disposal Facility Performance Assessment

    SciTech Connect

    Bergeron, Marcel P.; Wurstner, Signe K.

    2000-12-04

    This report summarizes the Hanford Site-Wide Groundwater Model and its application to the Immobilized Low-Activity Waste (ILAW) Disposal Facility Performance Assessment (PA). The site-wide model and supporting local-scale models are used to evaluate impacts from the transport of contaminants at a hypothetical well 100 m downgradient of the disposal facilities and to evaluate regional flow conditions and transport from the ILAW disposal facilities to the Columbia River. These models were used to well-intercept factors (WIFs) or dilution factors from a given areal flux of a hypothetical contaminant released to the unconfined aquifer from the ILAW disposal facilities for two waste-disposal options: 1) a remote-handled trench concept and 2) a concrete-vault concept. The WIF is defined as the ratio of the concentration at a well location in the aquifer to the concentration of infiltrating water entering the aquifer. These WIFs are being used in conjunction with calculations of released contaminant fluxes through the vadose zone to estimate potential impacts from radiological and hazardous chemical contaminants within the ILAW disposal facility at compliance points.

  6. Neutron irradiation effects on the microstructure of low-activation ferritic alloys*1

    NASA Astrophysics Data System (ADS)

    Kimura, A.; Matsui, H.

    1994-09-01

    Microstructures of low-activation ferritic alloys, such as 2.25% Cr-2% W, 7% Cr-2% W, 9% Cr-2% W and 12% Cr-2% W alloys, were observed after FFTF irradiation at 698 K to a dose of 36 dpa. Martensite in 7% Cr-2% W, 9% Cr-2% W and 12% Cr-2% W alloys and bainite in 2.25% Cr-2% W alloy were fairly stable after the irradiation. Microvoids were observed in the martensite in each alloy but not in bainite and δ-ferrite in 12% Cr-2% W alloys. An addition of 0.02% Ti to 9% Cr-2% W alloy considerably reduced the void density. Spherical (Ta, W) and Ti-rich precipitates were observed in the Ti-added 9% Cr-2% W alloy. Precipitates observed in 9% Cr-2% W and 7% Cr-2% W alloys are mainly Cr-rich M 23C 6 (Ta, W) and Ta(W)-rich M 6C and Fe-rich Laves phase. In 2.25% Cr-2% W alloy, high density of fine (Ta, W)-rich M 2C type precipitates as well as M 6C were observed. Spherical small α' Cr-rich particles were observed in both martensite and α-ferrite in 12% Cr-2% W alloys. Correlation between postirradiation microstructure and irradiation hardening is shown and discussed for these alloys.

  7. Iodine solubility in a low-activity waste borosilicate glass at 1000 °C

    NASA Astrophysics Data System (ADS)

    Riley, Brian J.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; Williams, Benjamin D.; Iovin, Cristian; Rodriguez, Carmen P.; Overman, Nicole R.; Bowden, Mark E.; Dixon, Derek R.; Crum, Jarrod V.; McCloy, John S.; Kruger, Albert A.

    2014-09-01

    The purpose of this study was to determine the solubility of iodine in a low-activity waste borosilicate glass when heated inside an evacuated and sealed fused quartz ampoule. The iodine was added to glass frit as KI in quantities of 99.4-24,005 ppm iodine (by mass). Each mixture was added to an ampoule, heated at 1000 °C for 2 h, and then air quenched. In samples with ⩾11,999 ppm iodine, low viscosity salt phases were observed on the surface of the melts that solidified into a white coating upon cooling. These salts were identified by X-ray diffraction as mixtures of KI, NaI, and Na2SO4. Iodine concentrations in glass specimens were analyzed with inductively-coupled plasma mass spectrometry, and the overall iodine solubility was determined to be 10,000 ppm. Several crystalline inclusions of iodine sodalite, Na8(AlSiO4)6I2, were observed in the 24,005 ppm specimen.

  8. Development of Simulants to Support Mixing Tests for High Level Waste and Low Activity Waste

    SciTech Connect

    EIBLING, RUSSELLE.

    2004-06-01

    The objectives of this study were to develop two different types of simulants to support vendor agitator design studies and mixing studies. The initial simulant development task was to develop rheologically-bounding physical simulants and the final portion was to develop a nominal chemical simulant which is designed to match, as closely as possible, the actual sludge from a tank. The physical simulants to be developed included a lower and upper rheologically bounded: pretreated low activity waste (LAW) physical simulant; LAW melter feed physical simulant; pretreated high level waste (HLW) physical simulant; HLW melter feed physical simulant. The nominal chemical simulant, hereafter referred to as the HLW Precipitated Hydroxide simulant, is designed to represent the chemical/physical composition of the actual washed and leached sludge sample. The objective was to produce a simulant which matches not only the chemical composition but also the physical properties of the actual waste sample. The HLW Precipitated Hydroxide simulant could then be used for mixing tests to validate mixing, homogeneity and representative sampling and transferring issues. The HLW Precipitated Hydroxide simulant may also be used for integrated nonradioactive testing of the WTP prior to radioactive operation.

  9. Effects of neutron irradiation on microstructural evolution in candidate low activation ferritic steels

    NASA Astrophysics Data System (ADS)

    Kohno, Yutaka; Kohyama, Akira; Yoshino, Masahiko; Asakura, Kentaro

    1994-09-01

    Fe-(2.25-12)Cr-2W-V, Ta low activation ferritic steels (JLF series steels) were developed in the fusion materials development program of Japanese universities. Microstructural observations, including precipitation response, were performed after neutron irradiation in the FFTF/MOTA. The preirradiation microstructure was stable after irradiation at low temperature (< 683 K). Recovery of martensitic lath structure and coarsening of precipitates took place above 733 K. Precipitates observed after irradiation were the same as those in unirradiated materials in 7-9Cr steels, and no irradiation induced phase was identified. The irradiation induced shift in DBTT in the 9Cr-2W steel proved to be very small which is a reflection of stable precipitation response in these steels. A high density of fine α' precipitates was observed in the 12Cr steel which might be responsible for the large irradiation hardening found in the 12Cr steel. Void formation was observed in 7-9Cr steels irradiated at 683 K, but the amount of void swelling was very small.

  10. Millimeter-Wave High Level and Low Activity Waste Glass Research

    SciTech Connect

    Woskov, Paul P.

    2005-06-01

    The primary objectives of the current research is to develop on-line sensors for characterizing molten glass in high-level and low-activity waste glass melters using millimeter-wave (MMW) technology and to use this technology to do novel research of melt dynamics. Existing and planned waste glass melters lack sophisticated diagnostics due to the hot, corrosive, and radioactive melter environments. Without process control diagnostics the Defense Waste Processing Facility (DWPF) and the Waste Treatment Plant (WTP) under construction at Hanford operate by a feed forward process control scheme that relies on predictive models with large uncertainties. This scheme severely limits production throughput and waste loading. Also operations at DWPF have shown susceptibility to anomalies such as foaming and combustion gas build up, which can seriously disrupt operations. Future waste chemistries will be even more challenging. The scientific goals of this project are to develop new reliable on-line monitoring capability for important glass process parameters such as temperature profiles, emissivity, density, viscosity, and other characteristics using the unique advantages of millimeter-wave electromagnetic radiation. Once successfully developed and implemented, significant cost savings would be realized in melter operations by increasing production through put, reduced storage volumes (through higher waste loading), and reduced risks (prevention or mitigation of anomalies).

  11. Redox-Dependent Solubility of Technetium in Low Activity Waste Glass

    SciTech Connect

    Soderquist, Chuck Z.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; Mccloy, John S.

    2014-03-01

    The solubility of technetium was measured in a Hanford low activity waste glass simulant. The simulant glass was melted, quenched and pulverized to make a stock of powdered glass. A series of glass samples were prepared using the powdered glass and varying amounts of solid potassium pertechnetate. Samples were melted at 1000°C in sealed fused quartz ampoules. After cooling, the bulk glass and the salt phase above the glass (when present) were sampled for physical and chemical characterization. Technetium was found in the bulk glass up to 2000 ppm (using the glass as prepared) and 3000 ppm (using slightly reducing conditions). The chemical form of technetium obtained by x-ray absorption near edge spectroscopy can be mainly assigned to isolated Tc(IV), with a minority of Tc(VII) in some glasses and TcO2 in two glasses. The concentration and speciation of technetium depends on glass redox and amount of technetium added. Solid crystals of pertechnetate salts were found in the salt cake layer that formed at the top of some glasses during the melt.

  12. Morphine-Stimulated Nitric Oxide Release in Rabbit Aqueous Humor

    PubMed Central

    Dortch-Carnes, Juanita; Russell, Karen

    2007-01-01

    Recent studies in our laboratory have demonstrated a role of nitric oxide (NO) in morphine-induced reduction of intraocular pressure (IOP) and pupil diameter (PD) in the New Zealand white (NZW) rabbit. The present study was designed to determine the effect of morphine on NO release in the aqueous humor of NZW rabbits, as this effect could be associated with morphine-mediated changes in aqueous humor dynamics and iris function. Dark adapted NZW rabbits were treated as follows: 1) treatment with morphine (10, 33 or 100 μg, 5 min); 2) treatment with morphine or endomorphin-1 for 5, 15 or 30 min; 3) pretreatment with naloxone (100 μg), L-NAME (125 μg) or reduced glutathione (GSH, 100 μg) for 30 minutes, followed by treatment with morphine (100 μg, 5 min). After the various treatment regimens, aqueous humor samples were obtained by paracenthesis and immediately assayed for nitrates and nitrites (an index of NO production), using a microplate assay kit. Morphine caused a dose-dependent increase in the levels of NO in aqueous humor after 5 min of treatment with each dose. Rabbits treated with endomorphin-1 (100 μg) had no significant change in NO levels in aqueous at any point in the time course. Aqueous samples from rabbits treated with morphine (100 μg) for 5 minutes increased from 29.84 ± 2.39 μM (control) to 183.94 ± 23.48 μM (treated). The increase in NO levels by morphine (100 μg, 5 min) was completely inhibited in the presence of naloxone (100 μg), L-NAME (125 μg) or GSH (100 μg). These results indicate that morphine-induced increase in NO production in aqueous humor is a transient response that is linked to activation of mu opioid receptors. Data obtained suggest that morphine-stimulated changes in ocular hydrodynamics and iris function are due, in part, to increased release of NO in aqueous humor. In addition, the sensitivity of the response to L-NAME and GSH suggests that morphine-induced release of nitric oxide into aqueous humor is mediated by

  13. White paper: cleanout of tank 241-AP-108 for storage of phase 1 pretreated low-activity waste

    SciTech Connect

    PLACE, D.E.

    1999-06-24

    This white paper evaluates the feasibility of cleaning tank 241-AP-108 for storage of pretreated low-activity waste. The maximum allowable heel inventories for {sup 90}Sr, {sup 99}Tc, {sup 137}Cs, and TRu are established. Cesium-137 was found to be the limiting radionuclide for tank 241-AP-108 cleanout. Equipment requirements for cleanout are identified and risks associated with extended storage of pretreated low-activity waste are discussed. This evaluation assumes that tank 241-AP-108 will be used for storage of pretreated low-activity waste from tanks 241-AZ-101 and 241-AZ-102 in accordance with the 1996 Tank Waste Remediation System Privatization Contract with BNFL Inc. Alternatives are currently under development that would not require this storage function. This document is being issued to capture the work performed to date.

  14. Radiation and Health Technology Laboratory Capabilities

    SciTech Connect

    Goles, Ronald W.; Johnson, Michelle Lynn; Piper, Roman K.; Peters, Jerry D.; Murphy, Mark K.; Mercado, Mike S.; Bihl, Donald E.; Lynch, Timothy P.

    2003-07-15

    The Radiological Standards and Calibrations Laboratory, a part of Pacific Northwest National Laboratory (PNNL)(a) performs calibrations and upholds reference standards necessary to maintain traceability to national standards. The facility supports U.S. Department of Energy (DOE) programs at the Hanford Site, programs sponsored by DOE Headquarters and other federal agencies, radiological protection programs at other DOE and commercial nuclear sites and research and characterization programs sponsored through the commercial sector. The laboratory is located in the 318 Building of the Hanford Site's 300 Area. The facility contains five major exposure rooms and several laboratories used for exposure work preparation, low-activity instrument calibrations, instrument performance evaluations, instrument maintenance, instrument design and fabrication work, thermoluminescent and radiochromic Dosimetry, and calibration of measurement and test equipment (M&TE). The major exposure facilities are a low-scatter room used for neutron and photon exposures, a source well room used for high-volume instrument calibration work, an x-ray facility used for energy response studies, a high-exposure facility used for high-rate photon calibration work, a beta standards laboratory used for beta energy response studies and beta reference calibrations and M&TE laboratories. Calibrations are routinely performed for personnel dosimeters, health physics instrumentation, photon and neutron transfer standards alpha, beta, and gamma field sources used throughout the Hanford Site, and a wide variety of M&TE. This report describes the standards and calibrations laboratory.

  15. Radiation and Health Technology Laboratory Capabilities

    SciTech Connect

    Bihl, Donald E.; Lynch, Timothy P.; Murphy, Mark K.; Myers, Lynette E.; Piper, Roman K.; Rolph, James T.

    2005-07-09

    The Radiological Standards and Calibrations Laboratory, a part of Pacific Northwest National Laboratory (PNNL)(a) performs calibrations and upholds reference standards necessary to maintain traceability to national standards. The facility supports U.S. Department of Energy (DOE) programs at the Hanford Site, programs sponsored by DOE Headquarters and other federal agencies, radiological protection programs at other DOE and commercial nuclear sites and research and characterization programs sponsored through the commercial sector. The laboratory is located in the 318 Building of the Hanford Site's 300 Area. The facility contains five major exposure rooms and several laboratories used for exposure work preparation, low-activity instrument calibrations, instrument performance evaluations, instrument maintenance, instrument design and fabrication work, thermoluminescent and radiochromic Dosimetry, and calibration of measurement and test equipment (M&TE). The major exposure facilities are a low-scatter room used for neutron and photon exposures, a source well room used for high-volume instrument calibration work, an x-ray facility used for energy response studies, a high-exposure facility used for high-rate photon calibration work, a beta standards laboratory used for beta energy response studies and beta reference calibrations and M&TE laboratories. Calibrations are routinely performed for personnel dosimeters, health physics instrumentation, photon and neutron transfer standards alpha, beta, and gamma field sources used throughout the Hanford Site, and a wide variety of M&TE. This report describes the standards and calibrations laboratory.

  16. Aspiration tests in aqueous foam using a breathing simulator

    SciTech Connect

    Archuleta, M.M.

    1995-12-01

    Non-toxic aqueous foams are being developed by Sandia National Laboratories (SNL) for the National Institute of Justice (NIJ) for use in crowd control, cell extractions, and group disturbances in the criminal justice prison systems. The potential for aspiration of aqueous foam during its use and the resulting adverse effects associated with complete immersion in aqueous foam is of major concern to the NIJ when examining the effectiveness and safety of using this technology as a Less-Than-Lethal weapon. This preliminary study was designed to evaluate the maximum quantity of foam that might be aspirated by an individual following total immersion in an SNL-developed aqueous foam. A.T.W. Reed Breathing simulator equipped with a 622 Silverman cam was used to simulate the aspiration of an ammonium laureth sulfate aqueous foam developed by SNL and generated at expansion ratios in the range of 500:1 to 1000:1. Although the natural instinct of an individual immersed in foam is to cover their nose and mouth with a hand or cloth, thus breaking the bubbles and decreasing the potential for aspiration, this study was performed to examine a worst case scenario where mouth breathing only was examined, and no attempt was made to block foam entry into the breathing port. Two breathing rates were examined: one that simulated a sedentary individual with a mean breathing rate of 6.27 breaths/minute, and one that simulated an agitated or heavily breathing individual with a mean breathing rate of 23.7 breaths/minute. The results of this study indicate that, if breathing in aqueous foam without movement, an air pocket forms around the nose and mouth within one minute of immersion.

  17. State of Supported Nickel Nanoparticles during Catalysis in Aqueous Media

    SciTech Connect

    Chase, Zizwe; Kasakov, Stanislav; Shi, Hui; Vjunov, Aleksei; Fulton, John L.; Camaioni, Donald M.; Balasubramanian, Mahalingam; Zhao, Chen; Wang, Yong; Lercher, Johannes A.

    2015-11-09

    The state of Ni supported on HZSM-5 zeolite, silica, and sulfonated carbon was determined during aqueous phase catalysis of phenol hydrodeoxygenation using in situ extended X-ray absorption fine structure spectroscopy (EXAFS). On sulfonated carbon and HZSM-5 supports, the NiO and Ni(OH)2 were readily reduced to Ni(0) under reaction conditions (~35 bar H2 in aqueous phenol solutions containing up to 0.5 wt. % phosphoric acid at 473 K). On the silica support, less than 70% of the Ni was converted to Ni(0) under reaction conditions, which is attributed to the formation of Ni phyllosilicates. Over a broad range of reaction conditions there was no leaching of Ni from the supports. In contrast, rapid leaching of the Ni(II) from HZSM-5 was observed, when 15 wt. % aqueous acetic acid was substituted for the aqueous phenol solution. Once the metallic state of Ni was established there was no leaching in 15 wt. % acetic acid at 473 K and 35 bar H2. This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences (BES), Division of Chemical Sciences, Geosciences & Biosciences. The STEM was supported under the Laboratory Directed Research and Development Program: Chemical Imaging Initiative at Pacific Northwest National Laboratory (PNNL), a multi-program national laboratory operated for DOE by Battelle under Contract DE-AC05-76RL01830. STEM was performed at EMSL, a DOE Office of Science user facility sponsored by the Office of Biological and Environmental Research and located at PNNL.

  18. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-99 Status Report

    SciTech Connect

    Herbst, Alan Keith; Mc Cray, John Alan; Kirkham, Robert John; Pao, Jenn Hai; Hinckley, Steve Harold

    1999-10-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1999, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed on radionuclide leaching, microbial degradation, waste neutralization, and a small mockup for grouting the INTEC underground storage tank residual heels.

  19. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-99 Status Report

    SciTech Connect

    A. K. Herbst; J. A. McCray; R. J. Kirkham; J. Pao; S. H. Hinckley

    1999-09-30

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1999, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed on radionuclide leaching, microbial degradation, waste neutralization, and a small mockup for grouting the INTEC underground storage tank residual heels.

  20. Ion segregation in aqueous solutions.

    PubMed

    Bian, Hongtao; Li, Jiebo; Zhang, Qiang; Chen, Hailong; Zhuang, Wei; Gao, Yi Qin; Zheng, Junrong

    2012-12-13

    Microscopic structures and dynamics of aqueous salt solutions were investigated with the ultrafast vibrational energy exchange method and anisotropy measurements. In KSCN aqueous solutions of various concentrations, the rotational time constants of SCN(-) anions are proportional to the viscosities of the solutions. However, the reorientation dynamics of the water molecules are only slightly affected by the solution viscosity. With the addition of strongly hydrated F(-) anions, the rotations of both SCN(-) anions and water molecules slow down. With the addition of weakly hydrated I(-) anions, only the rotation of SCN(-) anions slows down with that of water molecules unaffected. Vibrational energy exchange measurements show that the separation among SCN(-) anions decreases with the addition of F(-) and increases with the addition of I(-). The series of experiments clearly demonstrate that both structures and dynamics of ion and water are segregated in the strong electrolyte aqueous solutions.

  1. Good laboratory practice and laboratory accreditation.

    PubMed

    Lawrence, J; McQuaker, N

    1993-12-01

    Principles of good laboratory practice (GLP) and laboratory accreditation programs, particularly as they pertain to the environmental sector, are reviewed. The multitude of programs is proving costly for many laboratories and there is mounting pressure to develop reciprocity agreements between programs and to consolidate nationally and internationally. Inclusion of GLP and laboratory accreditation requirements in government regulations is resulting in a significantly increased number of laboratories participating in these programs.

  2. Road Transportable Analytical Laboratory (RTAL) system: Volume II, Appendices A and B. Final report

    SciTech Connect

    Finger, S.M.; De Avila, J.C.; Keith, V.F.

    1996-08-01

    The Road Transportable Analytical Laboratory (RTAL) provides a portable analytical system for the analysis of soils, ground water, and surface water for the detection of hazardous materials, metals, organics, and radioactive material. This report presents the data results for an aqueous sample VOA report and an aqueous sample SVOA report.

  3. Immunoglobulins in human aqueous humour.

    PubMed Central

    Sen, D. K.; Sarin, G. S.; Saha, K.

    1977-01-01

    The immunoglobulin concentrations in human aqueous humour from 44 patients aged 35 to 85 years with cataracts were measured by a standard immunodiffusion method. IgG was found in all the samples (mean level 7-0 mg/100 ml. IgD, IgA or IgM could not be detected. There was no significant difference in IgG levels in aqueous humour between the two sexes, in different age groups, and in the different types of cataracts. PMID:403928

  4. Aqueous solutions of uranium(VI) as studied by time-resolved emission spectroscopy: a round-robin test.

    PubMed

    Billard, Isabelle; Ansoborlo, Eric; Apperson, Kathleen; Arpigny, Sylvie; Azenha, M Emilia; Birch, David; Bros, Pascal; Burrows, Hugh D; Choppin, Gregory; Couston, Laurent; Dubois, Veronique; Fanghänel, Thomas; Geipel, Gerhard; Hubert, Solange; Kim, Jae I; Kimura, Takaumi; Klenze, Reinhardt; Kronenberg, Andreas; Kumke, Michael; Lagarde, Gerard; Lamarque, Gerard; Lis, Stefan; Madic, Charles; Meinrath, Gunther; Moulin, Christophe; Nagaishi, Ryuji; Parker, David; Plancque, Gabriel; Scherbaum, Franz; Simoni, Eric; Sinkov, Sergei; Viallesoubranne, Carole

    2003-08-01

    Results of an inter-laboratory round-robin study of the application of time-resolved emission spectroscopy (TRES) to the speciation of uranium(VI) in aqueous media are presented. The round-robin study involved 13 independent laboratories, using various instrumentation and data analysis methods. Samples were prepared based on appropriate speciation diagrams and, in general, were found to be chemically stable for at least six months. Four different types of aqueous uranyl solutions were studied: (1) acidic medium where UO2(2+)aq is the single emitting species, (2) uranyl in the presence of fluoride ions, (3) uranyl in the presence of sulfate ions, and (4) uranyl in aqueous solutions at different pH, promoting the formation of hydrolyzed species. Results between the laboratories are compared in terms of the number of decay components, luminescence lifetimes, and spectral band positions. The successes and limitations of TRES in uranyl analysis and speciation in aqueous solutions are discussed.

  5. Regional Air Quality Model Application of the Aqueous-Phase ...

    EPA Pesticide Factsheets

    In most ecosystems, atmospheric deposition is the primary input of mercury. The total wet deposition of mercury in atmospheric chemistry models is sensitive to parameterization of the aqueous-phase reduction of divalent oxidized mercury (Hg2+). However, most atmospheric chemistry models use a parameterization of the aqueous-phase reduction of Hg2+ that has been shown to be unlikely under normal ambient conditions or use a non mechanistic value derived to optimize wet deposition results. Recent laboratory experiments have shown that Hg2+ can be photochemically reduced to elemental mercury (Hg) in the aqueous-phase by dissolved organic matter and a mechanism and the rate for Hg2+ photochemical reduction by dicarboxylic acids (DCA) has been proposed. For the first time in a regional scale model, the DCA mechanism has been applied. The HO2-Hg2+ reduction mechanism, the proposed DCA reduction mechanism, and no aqueous-phase reduction (NAR) of Hg2+ are evaluated against weekly wet deposition totals, concentrations and precipitation observations from the Mercury Deposition Network (MDN) using the Community Multiscale Air Quality (CMAQ) model version 4.7.1. Regional scale simulations of mercury wet deposition using a DCA reduction mechanism evaluated well against observations, and reduced the bias in model evaluation by at least 13% over the other schemes evaluated, although summertime deposition estimates were still biased by −31.4% against observations. The use of t

  6. Effect of Sulfate on Rhenium Partitioning during Melting of Low-Activity Waste Glass Feeds

    SciTech Connect

    Jin, Tongan; Kim, Dong-Sang; Schweiger, Michael J.

    2015-10-01

    The volatile loss of technetium-99 (99Tc) is a major concern of the low-activity waste (LAW) vitrification at Hanford. We investigated the incorporation and volatile loss of Re (a nonradioactive surrogate for 99Tc) during batch-to-glass conversion up to 1100°C. The AN-102 feed, which is one of the representative Hanford LAW feeds, containing 0.59 wt% of SO3 (in glass if 100% retained) was used. The modified sulfate-free AN-102_0S feed was also tested to investigate the effect of sulfate on Re partitioning and retention during melting. After heating of the dried melter feed (mixture of LAW simulant and glass forming/modifying additives) to different temperatures, the heat-treated samples were quenched. For each heat-treated sample, the salts (soluble components in room temperature leaching), early glass forming melt (soluble components in 80°C leaching), and insoluble solids were separated by a two-step leaching and the chemical compositions of each phase were quantitatively analyzed. The final retention ratio of AN-102 and AN-102_0S in glass (insoluble solids) are 32% and 63% respectively. The presence of sulfate in the salt phase between 600 and 800°C leads to a significantly higher Re loss via volatilization from the salt layer. At ≥800°C, for both samples, there is no more incorporation of Re into the insoluble phase because: for AN-102_0S there is no salt left i.e., the split into the insoluble and gas phases is complete by 800°C and for AN-102 all the Re contained in the remaining salt phase is lost through volatilization. The present results on the effect of sulfate, although not directly applicable to LAW vitrification in the melter, will be used to understand the mechanism of Re incorporation into glass to eventually develop the methods that can increase the 99Tc retention during LAW vitrification at Hanford.

  7. Office of River Protection Advanced Low-Activity Waste Glass Research and Development Plan

    SciTech Connect

    Peeler, David K.; Kim, Dong-Sang; Vienna, John D.; Schweiger, Michael J.; Piepel, Gregory F.

    2015-11-01

    The U.S. Department of Energy Office of River Protection (ORP) has initiated and leads an integrated Advanced Waste Glass (AWG) program to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product performance requirements. The integrated ORP program is focused on providing a technical, science-based foundation for making key decisions regarding the successful operation of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) facilities in the context of an optimized River Protection Project (RPP) flowsheet. The fundamental data stemming from this program will support development of advanced glass formulations, key product performance and process control models, and tactical processing strategies to ensure safe and successful operations for both the low-activity waste (LAW) and high-level waste vitrification facilities. These activities will be conducted with the objective of improving the overall RPP mission by enhancing flexibility and reducing cost and schedule. The purpose of this advanced LAW glass research and development plan is to identify the near-term, mid-term, and longer-term research and development activities required to develop and validate advanced LAW glasses, property-composition models and their uncertainties, and an advanced glass algorithm to support WTP facility operations, including both Direct Feed LAW and full pretreatment flowsheets. Data are needed to develop, validate, and implement 1) new glass property-composition models and 2) a new glass formulation algorithm. Hence, this plan integrates specific studies associated with increasing the Na2O and SO3/halide concentrations in glass, because these components will ultimately dictate waste loadings for LAW vitrification. Of equal importance is the development of an efficient and economic strategy for 99Tc management. Specific and detailed studies are being implemented to understand the fate of Tc throughout

  8. Toward understanding the effect of low-activity waste glass composition on sulfur solubility

    DOE PAGES

    Vienna, John D.; Kim, Dong -Sang; Muller, Isabelle S.; ...

    2014-07-24

    The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO3 on a calcined oxide basis) depending on the composition of the melter feed and processing conditions. If the amount of sulfur exceeds the melt tolerance level, a molten salt will accumulate, which may upset melter operations and potentially shorten the useful life of the melter. At the Hanford site, relatively conservative limits have been placed on sulfur loading in melter feed, which inmore » turn significantly increases the amount of glass that will be produced. Crucible-scale sulfur solubility data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO3 in glass based on 252 simulated Hanford low-activity waste (LAW) glass compositions. This model represents the data well, accounting for over 85% of the variation in data, and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed for 13 scaled melter tests of simulated LAW glasses. The model can be used to help estimate glass volumes and make informed decisions on process options. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li2O > V2O5> CaO ≈ P2O5 > Na2O ≈ B2O3 > K2O. The components that most decrease sulfur solubility are Cl > Cr2O3 > Al2O3 > ZrO2 ≈ SnO2 > Others ≈ SiO2. As a result, the order of component effects is similar to previous literature data, in most cases.« less

  9. Lessons Learned In Technology Development for Supplemental Treatment of Low-Activity Waste at Hanford

    SciTech Connect

    Biyani, R.K.

    2008-07-01

    Hanford needs supplemental technology treatment of low-activity waste (LAW) in addition to the Waste Treatment Plant (WTP). The Washington State Department of Ecology requires that supplemental technology provide the same protection to human health and the environment as WTP LAW glass. In 2002, the U.S. Department of Energy (US DOE) evaluated supplemental treatment technologies for LAW treatment and looked more closely at three: bulk vitrification (BV), steam reforming, and tailored cementitious stabilization. US DOE with Ecology's support chose to design and test BV because it believed BV would offer rapid deployment, low cost, and waste stream versatility. This paper will describe the path taken in choosing and developing technologies for additional LAW treatment capacity and, more importantly, the lessons learned along the way. In conclusion: Contractors' off-the-shelf vitrification technology that worked elsewhere may not apply easily to Hanford's waste challenges. The BV development process could have been improved by first identifying and then focusing on primary areas of concern. Continuing integrated tests at the Horn Rapids facility offers a convenient option to test both the dryer and the SMF. But the plan for development of the SMF must be short term with well defined success criteria. US DOE has the responsibility to carefully evaluate each proposal and make critical decisions that will make optimum use of limited funds. The ERP provided valuable technical guidance on improving BV's design. This must be complemented by a similar study of cost effectiveness of a process. We must have a better understanding of life cycle costs before a path for supplemental treatment is chosen. US DOE has now gained five years of experience in developing BV. It is time for US DOE to make defensible economic evaluations before further funding towards developing supplemental treatment. It must reevaluate if the projected advantages of rapid deployment, low cost, and waste

  10. Toward understanding the effect of low-activity waste glass composition on sulfur solubility

    SciTech Connect

    Vienna, John D.; Kim, Dong -Sang; Muller, Isabelle S.; Piepel, Greg F.; Kruger, Albert A.; Jantzen, C.

    2014-07-24

    The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO3 on a calcined oxide basis) depending on the composition of the melter feed and processing conditions. If the amount of sulfur exceeds the melt tolerance level, a molten salt will accumulate, which may upset melter operations and potentially shorten the useful life of the melter. At the Hanford site, relatively conservative limits have been placed on sulfur loading in melter feed, which in turn significantly increases the amount of glass that will be produced. Crucible-scale sulfur solubility data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO3 in glass based on 252 simulated Hanford low-activity waste (LAW) glass compositions. This model represents the data well, accounting for over 85% of the variation in data, and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed for 13 scaled melter tests of simulated LAW glasses. The model can be used to help estimate glass volumes and make informed decisions on process options. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li2O > V2O5> CaO ≈ P2O5 > Na2O ≈ B2O3 > K2O. The components that most decrease sulfur solubility are Cl > Cr2O3 > Al2O3 > ZrO2 ≈ SnO2 > Others ≈ SiO2. As a result, the order of component effects is similar to previous literature data, in most cases.

  11. 78 FR 65390 - Exemption From Licensing for Disposal of Low-Activity Radioactive Waste at the US Ecology Idaho...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-31

    ... COMMISSION Exemption From Licensing for Disposal of Low-Activity Radioactive Waste at the US Ecology Idaho... (SLC) site in Bloomsburg, Pennsylvania, at the US Ecology Idaho (USEI) Resource Conservation and... INFORMATION: I. Introduction The NRC staff is considering a request from the US Ecology, Inc. (US Ecology...

  12. Hanford Immobilized Low Activity Waste (ILAW) Performance Assessment 2001 Version [Formerly DOE/RL-97-69] [SEC 1 & 2

    SciTech Connect

    MANN, F.M.

    2000-08-01

    The Hanford Immobilized Low-Activity Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-activity fraction of waste presently contained in Hanford Site tanks. The tank waste is the byproduct of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste is stored in underground single- and double-shell tanks. The tank waste is to be retrieved, separated into low-activity and high-level fractions, and then immobilized by vitrification. The US. Department of Energy (DOE) plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at the Hanford Site until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to modify the current Disposal Authorization Statement for the Hanford Site that would allow the following: construction of disposal trenches; and filling of these trenches with ILAW containers and filler material with the intent to dispose of the containers.

  13. Low-activity spectrometric gamma-ray logging technique for delineation of coal/rock interfaces in dry blast holes.

    PubMed

    Asfahani, J; Borsaru, M

    2007-06-01

    A low-activity spectrometric gamma-ray logging technique is proposed in this paper as a sensitive tool for the delineation of coal/rock interfaces in dry blast holes. The advantages and superiority of this technique over traditional micro-density non-spectrometric gamma-ray tools are demonstrated.

  14. Low-activity radioactive materials management at the U.S. Department of Energy.

    PubMed

    Marcinowski, Frank; Tonkay, Douglas W

    2006-11-01

    The U.S. Department of Energy (U.S. DOE) is making significant progress with the cleanup of its legacy radioactively-contaminated facilities and sites left from research and development and production of nuclear materials and weapons. Sites like Rocky Flats, Battelle Columbus Laboratories, Fernald, Mound, Brookhaven National Laboratory, Hanford, and Oak Ridge are faced daily with decisions related to disposition of waste and radioactive material. One key to this success is the disposition of waste arising from cleanup. Most of the generated waste volume has very low levels of radioactive contamination. The waste includes contaminated soil, debris from demolition, or scrap metal and equipment. The cost of disposing of large volumes of waste can be prohibitive, so there is incentive to find innovative ways to disposition wastes. This paper describes the current status of policy development in this area, such as development of a draft programmatic environmental impact statement and monitoring of related rulemaking at the U.S. Nuclear Regulatory Commission. The paper also provides an overview of draft U.S. DOE guidance on control and release of property with residual radioactive material, and site-specific applications of DOE guidance.

  15. Localized chemistry of 99Tc in simulated low activity waste glass

    NASA Astrophysics Data System (ADS)

    Weaver, Jamie L.

    A priority of the United States Department of Energy (DOE) is to dispose of the nuclear waste accumulated in the underground tanks at the Hanford Nuclear Reservation in Richland, WA. Incorporation and stabilization of technetium (99Tc) from these tanks into vitrified waste forms is a concern to the waste glass community and DOE due to 99Tc's long half-life ( 2.13˙105 y), and its high mobility in the subsurface environment under oxidizing conditions. Working in collaboration with researchers at Pacific Northwest National Laboratory (PNNL) and other national laboratories, plans were formulated to obtain first-of-a-kind chemical structure determination of poorly understood and environmentally relevant technetium compounds that relate to the chemistry of the Tc in nuclear waste glasses. Knowledge of the structure and spectral signature of these compounds aid in refining the understanding of 99Tc incorporation into and release from oxide based waste glass. In this research a first-of-its kind mechanism for the behavior of 99Tc during vitrification is presented, and the structural role of Tc(VII) and (IV) in borosilicate waste glasses is readdressed.

  16. Aqueous-Spray Cleaning System

    NASA Technical Reports Server (NTRS)

    Morgan, Gene E.; Hoult, William S.; Simpson, Gareth L.

    1996-01-01

    Simple aqueous-spray cleaning system with overall dimensions comparable to large kitchen refrigerator constructed for use in cleaning hardware in shop. Made of commercially available parts and materials. Incorporates economical cleaner-and-rinse-recycling subsystem, as well as programmable logic-controller device for either manual or automatic operation.

  17. Aqueous-Spray Cleaning System

    NASA Technical Reports Server (NTRS)

    Morgan, Gene E.; Hoult, William S.; Simpson, Gareth L.

    1996-01-01

    Simple aqueous-spray cleaning system with overall dimensions comparable to large kitchen refrigerator constructed for use in cleaning hardware in shop. Made of commercially available parts and materials. Incorporates economical cleaner-and-rinse-recycling subsystem, as well as programmable logic-controller device for either manual or automatic operation.

  18. CESIUM RECOVERY FROM AQUEOUS SOLUTIONS

    DOEpatents

    Goodall, C.A.

    1960-09-13

    A process is given for precipitating cesium on zinc ferricyanide (at least 0.0004 M) from aqueous solutions containing mineral acid in a concentration of from 0.2 N acidity to 0.61 N acid-deficiency and advantageously, but not necessarily, also aluminum nitrate in a concentration of from l to 2.5 M.

  19. Aqueous Processing Material Accountability Instrumentation

    SciTech Connect

    Robert Bean

    2007-09-01

    Increased use of nuclear power will require new facilities. The U.S. has not built a new spent nuclear fuel reprocessing facility for decades. Reprocessing facilities must maintain accountability of their nuclear fuel. This survey report on the techniques used in current aqueous reprocessing facilities, and provides references to source materials to assist facility design efforts.

  20. Oligonucleofide Imprinting in Aqueous Environment

    DTIC Science & Technology

    2002-04-05

    imprint molecule for various organic and aqueous polymerization formulations (Table I). The polymer ...interactions (Table 1). Table 1. Polymer formulations used to imprint adenosine dimer 1. Molecularly imprinted polymer ( MIP ) using 1% dimer 1 as template ( MIP ... MIP P3 is compared to its rebinding with non- imprinted polymer P30. Cb is the amount of dimer rebound to the polymer . Cf is the

  1. Chemical reactions at aqueous interfaces

    NASA Astrophysics Data System (ADS)

    Vecitis, Chad David

    2009-12-01

    Interfaces or phase boundaries are a unique chemical environment relative to individual gas, liquid, or solid phases. Interfacial reaction mechanisms and kinetics are often at variance with homogeneous chemistry due to mass transfer, molecular orientation, and catalytic effects. Aqueous interfaces are a common subject of environmental science and engineering research, and three environmentally relevant aqueous interfaces are investigated in this thesis: 1) fluorochemical sonochemistry (bubble-water), 2) aqueous aerosol ozonation (gas-water droplet), and 3) electrolytic hydrogen production and simultaneous organic oxidation (water-metal/semiconductor). Direct interfacial analysis under environmentally relevant conditions is difficult, since most surface-specific techniques require relatively `extreme' conditions. Thus, the experimental investigations here focus on the development of chemical reactors and analytical techniques for the completion of time/concentration-dependent measurements of reactants and their products. Kinetic modeling, estimations, and/or correlations were used to extract information on interfacially relevant processes. We found that interfacial chemistry was determined to be the rate-limiting step to a subsequent series of relatively fast homogeneous reactions, for example: 1) Pyrolytic cleavage of the ionic headgroup of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) adsorbed to cavitating bubble-water interfaces during sonolysis was the rate-determining step in transformation to their inorganic constituents carbon monoxide, carbon dioxide, and fluoride; 2) ozone oxidation of aqueous iodide to hypoiodous acid at the aerosol-gas interface is the rate-determining step in the oxidation of bromide and chloride to dihalogens; 3) Electrolytic oxidation of anodic titanol surface groups is rate-limiting for the overall oxidation of organics by the dichloride radical. We also found chemistry unique to the interface, for example: 1

  2. Characterizing Fullerene Nanoparticles in Aqueous Suspensions

    EPA Science Inventory

    Studies have indicated that fullerenes can form stable colloidal suspensions in water when introduced to the aqueous phase through solvent exchange, sonication, or extended mixing. The colloidal suspensions created using these techniques have effective aqueous phase concentratio...

  3. Characterizing Fullerene Nanoparticles in Aqueous Suspensions

    EPA Science Inventory

    Studies have indicated that fullerenes can form stable colloidal suspensions in water when introduced to the aqueous phase through solvent exchange, sonication, or extended mixing. The colloidal suspensions created using these techniques have effective aqueous phase concentratio...

  4. Sporostatic and sporocidal properties of aqueous formaldehyde.

    NASA Technical Reports Server (NTRS)

    Trujillo, R.; David, T. J.

    1972-01-01

    Aqueous formaldehyde is shown to exert both sporostatic and sporocidal effects on Bacillus subtilis spores. The sporostatic effect is a result of the reversible inhibition of spore germination occasioned by aqueous formaldehyde; the sporocidal effect is due to the temperature-dependent inactivation of these spores in aqueous formaldehyde. The physicochemical state of formaldehyde in solution provides a framework with which to interpret both the sporostatic and sporocidal properties of aqueous formaldehyde.

  5. A Strategy to Conduct an Analysis of the Long-Term Performance of Low-Activity Waste Glass in a Shallow Subsurface Disposal System at Hanford

    SciTech Connect

    BP McGrail, WL Ebert, DH Bacon, DM Strachan

    1998-02-18

    Privatized services are being procured to vitrify low-activity tank wastes for eventual disposal in a shallow subsurface facility at the Hanford Site. Over 500,000 metric tons of low-activity waste glass will be generated, which is among the largest volumes of waste within the U.S. Department of Energy (DOE) complex and is one of the largest inventories of long-lived radionuclides planned for disposal in a low-level waste facility. Before immobilized waste can be disposed, DOE must approve a "performance assessment," which is a document that describes the impacts of the disposal facility on public health and environmental resources. Because the release rate of radionuclides from the glass waste form is a key factor determining these impacts, a sound scientific basis for determining their long-term release rates must be developed if this disposal action is to be accepted by regulatory agencies, stakeholders, and the public. In part, the scientific basis is determined from a sound testing strategy. The foundation of the proposed testing strategy is a well accepted mechanistic model that is being used to calculate the glass corrosion behavior over the geologic time scales required for performance assessment. This model requires that six parameters be determined, and the testing program is defined by an appropriate set of laboratory experiments to determine these parameters, and is combined with a set of field experiments to validate the model as a whole. Three general classes of laboratory tests are proposed in this strategy: 1) characterization, 2) accelerated, and 3) service condition. Characterization tests isolate and provide specific information about processes or parameters in theoretical models. Accelerated tests investigate corrosion behavior that will be important over the regulated service life of a disposal system within a laboratory time frame of a few years or less. Service condition tests verify that the techniques used in accelerated tests do not change

  6. DEVELOPMENT OF THE BULK VITRIFICATION TREATMENT PROCESS FOR THE LOW ACTIVITY FRACTION OF HANFORD SINGLE SHELL TANK WASTES

    SciTech Connect

    Thompson, L.E.; Lowery, P.S.; Arrowsmith, H.W.; Snyder, T.; McElroy, J.L.

    2003-02-27

    AMEC Earth & Environmental, Inc. and RWE NUKEM Corporation have teamed to develop and apply a waste pre-treatment and bulk vitrification process for low activity waste (LAW) from Hanford Single Shell Tanks (SSTs). The pretreatment and bulk vitrification process utilizes technologies that have been successfully deployed to remediate both radioactive and chemically hazardous wastes at nuclear power plants, DOE sites, and commercial waste sites in the US and abroad. The process represents an integrated systems approach. The proposed AMEC/NUKEM process follow the extraction and initial segregation activities applied to the tank wastes carried out by others. The first stage of the process will utilize NUKEM's concentrate dryer (CD) system to concentrate the liquid waste stream. The concentrate will then be mixed with soil or glass formers and loaded into refractory-lined steel containers for bulk vitrification treatment using AMEC's In-Container Vitrification (ICV) process. Following the vitrification step, a lid will be placed on the container of cooled, solidified vitrified waste, and the container transported to the disposal site. The container serves as the melter vessel, the transport container and the disposal container. AMEC and NUKEM participated in the Mission Acceleration Initiative Workshop held in Richland, Washington in April 2000 [1]. An objective of the workshop was to identify selected technologies that could be combined into viable treatment options for treatment of the LAW fraction from selected Hanford waste tanks. AMEC's ICV process combined with NUKEM's CD system and other remote operating capabilities were presented as an integrated solution. The Team's proposed process received some of the highest ratings from the Workshop's review panel. The proposed approach compliments the Hanford Waste Treatment Plant (WTP) by reducing the amount of waste that the WTP would have to process. When combined with the capabilities of the WTP, the proposed approach

  7. Secondary Organic Aerosol Produced from Aqueous Reactions of Phenols in Fog Drops and Deliquesced Particles

    NASA Astrophysics Data System (ADS)

    Smith, J.; Anastasio, C.

    2014-12-01

    The formation and evolution of secondary organic aerosol (SOA) in atmospheric condensed phases (i.e., aqueous SOA) can proceed rapidly, but relatively little is known of the important aqueous SOA precursors or their reaction pathways. In our work we are studying the aqueous SOA formed from reactions of phenols (phenol, guaiacol, and syringol), benzene-diols (catechol, resorcinol, and hydroquinone), and phenolic carbonyls (e.g., vanillin and syringaldehyde). These species are potentially important aqueous SOA precursors because they are released in large quantities from biomass burning, have high Henry's Law constants (KH = 103 -109 M-1 atm-1) and are rapidly oxidized. To evaluate the importance of aqueous reactions of phenols as a source of SOA, we first quantified the kinetics and SOA mass yields for 11 phenols reacting via direct photodegradation, hydroxyl radical (•OH), and with an excited organic triplet state (3C*). In the second step, which is the focus of this work, we use these laboratory results in a simple model of fog chemistry using conditions during a previously reported heavy biomass burning event in Bakersfield, CA. Our calculations indicate that under aqueous aerosol conditions (i.e., a liquid water content of 100 μg m-3) the rate of aqueous SOA production (RSOA(aq)) from phenols is similar to the rate in the gas phase. In contrast, under fog/cloud conditions the aqueous RSOA from phenols is 10 times higher than the rate in the gas phase. In both of these cases aqueous RSOA is dominated by the oxidation of phenols by 3C*, followed by direct photodegradation of phenolic carbonyls, and then •OH oxidation. Our results suggest that aqueous oxidation of phenols is a significant source of SOA during fog events and also during times when deliquesced aerosols are present.

  8. Aqueous based replacements for chlorinated solvents meeting standards while minimizing environmental liabilities

    SciTech Connect

    Arcuri, K.B.; Janes, J.V. III; Janes, K.N.

    1995-12-31

    The Clean Air Act of 1990 mandates the phaseout of many chlorinated solvents used in numerous cleaning and degreasing applications. Aqueous-based cleaners can be an effective alternative in many applications, however this changeover can require significant laboratory and pilot studies. Prior to the phaseout, little attention was given to the material balances and cleanliness requirements associated with many cleaning applications. Environmental regulations have forced many industries to evaluate material usage rates and waste management options associated with their cleaning applications. Aqueous-based cleaners offer the opportunity to minimize waste generation while achieving the desired cleanliness level. This paper will address the technical issues associated with identifying the types of surfactant and emulsion based organic aqueous cleaners which satisfy common cleaning scenarios. The critical issues typically include cleaning efficiency, management of the washwater, and disposal of cleaning residues. Aqueous cleaners generally offer significant advantages over other alternatives due to the flexibility in designing the most appropriate surfactant and emulsion chemistry.

  9. Aqueous cleaning and verification processes for precision cleaning of small parts

    NASA Technical Reports Server (NTRS)

    Allen, Gale J.; Fishell, Kenneth A.

    1995-01-01

    The NASA Kennedy Space Center (KSC) Materials Science Laboratory (MSL) has developed a totally aqueous process for precision cleaning and verification of small components. In 1990 the Precision Cleaning Facility at KSC used approximately 228,000 kg (500,000 lbs) of chlorofluorocarbon (CFC) 113 in the cleaning operations. It is estimated that current CFC 113 usage has been reduced by 75 percent and it is projected that a 90 percent reduction will be achieved by the end of calendar year 1994. The cleaning process developed utilizes aqueous degreasers, aqueous surfactants, and ultrasonics in the cleaning operation and an aqueous surfactant, ultrasonics, and Total Organic Carbon Analyzer (TOCA) in the nonvolatile residue (NVR) and particulate analysis for verification of cleanliness. The cleaning and verification process is presented in its entirety, with comparison to the CFC 113 cleaning and verification process, including economic and labor costs/savings.

  10. Chemistry Laboratory Safety Check

    ERIC Educational Resources Information Center

    Patnoe, Richard L.

    1976-01-01

    An accident prevention/safety check list for chemistry laboratories is printed. Included are checks of equipment, facilities, storage and handling of chemicals, laboratory procedures, instruction procedures, and items to be excluded from chemical laboratories. (SL)

  11. Flake storage effects on properties of laboratory-made flakeboards

    Treesearch

    C. G. Carll

    1998-01-01

    Aspen (Populus gradidentata) and loblolly pine (Pinus taeda) flakes were prepared with tangential-grain and radial-grain faces on a laboratory disk flaker. These were gently dried in a steam-heated rotary drum dryer. Approximately 1 week after drying, surface wettability was measured on a large sample of flakes using an aqueous dye solution. Three replicate boards of...

  12. Cesium recovery from aqueous solutions

    DOEpatents

    Goodhall, C. A.

    1960-09-13

    A process for recovering cesium from aqueous solutions is given in which precipitation on zinc ferricyanide is used. The precipitation is preferably carried out in solutions containing at least 0.0004M zinc ferricyanide, an acidity ranging from 0.2N mineral acid to 0.61N acid deficiency, and 1 to 2.5M aluminum nitrate. (D.L.C.)

  13. The Melting of Aqueous Foams

    NASA Technical Reports Server (NTRS)

    Durian, Douglas J.; Gopal, Anthony D.; Vera, Moin U.; Langer, Stephen A.

    1996-01-01

    Diffusing-wave spectroscopy measurements show that ordinarily solid aqueous foams flow by a series of stick-slip avalanche-like rearrangements of neighboring bubbles from one tight packing configuration to another. Contrary to a recent prediction, the distribution of avalanche sizes do not obey a power-law distribution characteristic of self-organized criticality. This can be understood from a simple model of foam mechanics based on bubble-bubble interactions.

  14. Stabilized aqueous hydrogen peroxide solution

    SciTech Connect

    Malin, M.J.; Sciafani, L.D.

    1988-05-17

    This patent describes a stabilized aqueous hydrogen peroxide solution having a pH below 7 and an amount of Ferric ion up to about 2 ppm comprising hydrogen peroxide, acetanilide having a concentration which ranges between 0.74 M Mol/L and 2.22 mMol/L, and o-benzene disulfonic acid or salt thereof at a concentration between about 0.86 mMol/L to about 1.62 mMol/L.

  15. Statement of Work (SOW) for FY 2001 to FY 2006 for the Hanford Low Activity Tank Waste Performance Assessment Program

    SciTech Connect

    PUIGH, R.J.

    2000-07-25

    This document describes the tasks included in the Hanford Low-Activity Tank Waste Performance Assessment activity though the close of the project in 2028. Near-term (2001-2006) tasks are described in detail, while tasks further in the future are simply grouped by year. The major tasks are displayed in the table provided. The major goals of the performance assessment activity are to provide the technical basis for the Department of Energy to continue to authorize the construction of disposal facilities, the onsite disposal of immobilized low-activity Hanford tank waste in those facilities, and the closure of the disposal facilities. Other significant goals are to provide the technical basis for the setting of the specifications of the immobilized waste and to support permitting of the disposal facilities.

  16. Effects of neutron irradiation on hydrogen-induced intergranular fracture in a low activation 9%Cr-2%W steel

    NASA Astrophysics Data System (ADS)

    Kimura, A.; Kayano, H.; Narui, M.

    1991-03-01

    Hydrogen charging changed the fracture mode in tensile tests at room temperature from ductile shear rupture to intergranular cracking, resulting in a considerable reduction of the ductility of a low activation 9%Cr-2%W martensitic steel. The critical hydrogen charging current density required to cause hydrogen-induced intergranular cracking was reduced by neutron irradiation, suggesting that neutron irradiation enhanced hydrogen-induced intergranular cracking. This hydrogen-induced intergranular cracking was not caused by irreversible damage due to hydrogen charging, since it disappeared after aging at room temperature. The recovery rate of the fracture mode from intergranular cracking to ductile rupture during aging at room temperature was reduced by irradiation. A mechanism of irradiation-induced enhancement of hydrogen embrittlement in a low activation 9%Cr-2%W martensitic steel is proposed.

  17. A Strategy for Maintenance of the Long-Term Performance Assessment of Immobilized Low-Activity Waste Glass

    SciTech Connect

    Ryan, Joseph V.; Freedman, Vicky L.

    2016-09-28

    Approximately 50 million gallons of high-level radioactive mixed waste has accumulated in 177 buried single- and double-shell tanks at the Hanford Site in southeastern Washington State as a result of the past production of nuclear materials, primarily for defense uses. The United States Department of Energy (DOE) is proceeding with plans to permanently dispose of this waste. Plans call for separating the tank waste into high-level waste (HLW) and low-activity waste (LAW) fractions, which will be vitrified at the Hanford Waste Treatment and Immobilization Plant (WTP). Principal radionuclides of concern in LAW are 99Tc, 129I, and U, while non-radioactive contaminants of concern are Cr and nitrate/nitrite. HLW glass will be sent off-site to an undetermined federal site for deep geological disposal while the much larger volume of immobilized low-activity waste will be placed in the on-site, near-surface Integrated Disposal Facility (IDF).

  18. Aqueous effluent tritium monitor development

    SciTech Connect

    Hofstetter, K.J.; Wilson, H.T.

    1991-12-31

    The development of a low-level tritium monitor for aqueous effluents has explored several potential techniques. In one method, a water-immiscible liquid scintillation cocktail was ultrasonically mixed with an aqueous sample to form a water-cocktail dispersion which was analyzed by liquid scintillation spectrometry. The organic cocktail could then be reused after phase separation. Of the cocktails tested, the highest tritium detection efficiency (7%) was determined for a toluene-based cocktail. In another technique, the response of various solid scintillators (plastic beads, crushed inorganic salts, etc.) to tritium solutions was measured. A 2% tritium detection efficiency was observed for the most efficient solid scintillators tested. In a third method, a large surface area detector was constructed from thin fibers of plastic scintillator. This detector had a 0.1% intrinsic tritium detection efficiency. While sensitivities of {approximately}25 kBg/L of tritium for a short count have been attained using several of these techniques, non can reach the environmental level of <1 kBg/L in aqueous solutions.

  19. Aqueous effluent tritium monitor development

    SciTech Connect

    Hofstetter, K.J.; Wilson, H.T.

    1991-01-01

    The development of a low-level tritium monitor for aqueous effluents has explored several potential techniques. In one method, a water-immiscible liquid scintillation cocktail was ultrasonically mixed with an aqueous sample to form a water-cocktail dispersion which was analyzed by liquid scintillation spectrometry. The organic cocktail could then be reused after phase separation. Of the cocktails tested, the highest tritium detection efficiency (7%) was determined for a toluene-based cocktail. In another technique, the response of various solid scintillators (plastic beads, crushed inorganic salts, etc.) to tritium solutions was measured. A 2% tritium detection efficiency was observed for the most efficient solid scintillators tested. In a third method, a large surface area detector was constructed from thin fibers of plastic scintillator. This detector had a 0.1% intrinsic tritium detection efficiency. While sensitivities of {approximately}25 kBg/L of tritium for a short count have been attained using several of these techniques, non can reach the environmental level of <1 kBg/L in aqueous solutions.

  20. Amphoteric Aqueous Hafnium Cluster Chemistry.

    PubMed

    Goberna-Ferrón, Sara; Park, Deok-Hie; Amador, Jenn M; Keszler, Douglas A; Nyman, May

    2016-05-17

    Selective dissolution of hafnium-peroxo-sulfate films in aqueous tetramethylammonium hydroxide enables extreme UV lithographic patterning of sub-10 nm HfO2 structures. Hafnium speciation under these basic conditions (pH>10), however, is unknown, as studies of hafnium aqueous chemistry have been limited to acid. Here, we report synthesis, crystal growth, and structural characterization of the first polynuclear hydroxo hafnium cluster isolated from base, [TMA]6 [Hf6 (μ-O2 )6 (μ-OH)6 (OH)12 ]⋅38 H2 O. The solution behavior of the cluster, including supramolecular assembly via hydrogen bonding is detailed via small-angle X-ray scattering (SAXS) and electrospray ionization mass spectrometry (ESI-MS). The study opens a new chapter in the aqueous chemistry of hafnium, exemplifying the concept of amphoteric clusters and informing a critical process in single-digit-nm lithography. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Sucrose diffusion in aqueous solution

    PubMed Central

    Murray, Benjamin J.

    2016-01-01

    The diffusion of sugar in aqueous solution is important both in nature and in technological applications, yet measurements of diffusion coefficients at low water content are scarce. We report directly measured sucrose diffusion coefficients in aqueous solution. Our technique utilises a Raman isotope tracer method to monitor the diffusion of non-deuterated and deuterated sucrose across a boundary between the two aqueous solutions. At a water activity of 0.4 (equivalent to 90 wt% sucrose) at room temperature, the diffusion coefficient of sucrose was determined to be approximately four orders of magnitude smaller than that of water in the same material. Using literature viscosity data, we show that, although inappropriate for the prediction of water diffusion, the Stokes–Einstein equation works well for predicting sucrose diffusion under the conditions studied. As well as providing information of importance to the fundamental understanding of diffusion in binary solutions, these data have technological, pharmaceutical and medical implications, for example in cryopreservation. Moreover, in the atmosphere, slow organic diffusion may have important implications for aerosol growth, chemistry and evaporation, where processes may be limited by the inability of a molecule to diffuse between the bulk and the surface of a particle. PMID:27364512

  2. Carbon Characterization Laboratory Readiness to Receive Irradiated Graphite Samples

    SciTech Connect

    Karen A. Moore

    2011-05-01

    The Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center. The CCL was established under the Next Generation Nuclear Plant Project to support graphite and ceramic composite research and development activities. The research conducted in this laboratory will support the Advanced Graphite Creep experiments—a major series of material irradiation experiments within the Next Generation Nuclear Plant Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, silicon-carbide composite, and ceramic materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials. Major infrastructural modifications were undertaken to support this new radiological facility at Idaho National Laboratory. Facility modifications are complete, equipment has been installed, radiological controls and operating procedures have been established and work management documents have been created to place the CCL in readiness to receive irradiated graphite samples.

  3. Influence of traps on the deuterium behaviour in the low activation martensitic steels F82H and Batman

    NASA Astrophysics Data System (ADS)

    Serra, E.; Perujo, A.; Benamati, G.

    1997-06-01

    A time dependent permeation method is used to measure the permeability, diffusivity and solubility of deuterium in the low activation martensitic steels F82H and Batman. The measurements cover the temperature range from 373 to 743 K which includes the onset of deuterium trapping effects on diffusivity and solubility. The results are interpreted using a trapping model. The number of trap sites and their average energies for deuterium in F82H and Batman steels are determined.

  4. [Theme: Using Laboratories.

    ERIC Educational Resources Information Center

    Pritchard, Jack; Braker, Clifton

    1982-01-01

    Pritchard discusses the opportunities for applied learning afforded by laboratories. Braker describes the evaluation of cognitive, affective, and psychomotor skills in the agricultural mechanics laboratory. (SK)

  5. Aggregation of Montmorillonite and Organic Matter in Aqueous Media Containing Artificial Seawater

    DTIC Science & Technology

    2009-01-23

    laboratory kaolinite and montmorillonite aggregation in which the dispersion-aggregation properties of pure clay suspensions were found to be primarily...Article 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Aggregation of montmorillonite and organic matter in aqueous media containing...properties of suspended colloids and aggregates) were determined for systems containing suspended montmorillonite , humic acid, and/or chitin at the

  6. Development of the Aqueous Processes for Removing NOx from Flue Gases.

    ERIC Educational Resources Information Center

    Chappell, Gilford A.

    A screening study was conducted to evaluate the capability of aqueous solutions to scrub NOx from the flue gases emitted by stationary power plants fired with fossil fuels. The report summarizes the findings of this laboratory program. The experimental program studied the following media for absorption of NOx from flue gases containing no NOx:…

  7. Development of the Aqueous Processes for Removing NOx from Flue Gases.

    ERIC Educational Resources Information Center

    Chappell, Gilford A.

    A screening study was conducted to evaluate the capability of aqueous solutions to scrub NOx from the flue gases emitted by stationary power plants fired with fossil fuels. The report summarizes the findings of this laboratory program. The experimental program studied the following media for absorption of NOx from flue gases containing no NOx:…

  8. Waste Form Release Data Package for the 2001 Immobilized Low-Activity Waste Performance Assessment

    SciTech Connect

    McGrail, B. Peter; Icenhower, Jonathan P.; Martin, Paul F.; Schaef, Herbert T.; O'Hara, Matthew J.; Rodriguez, Eugenio; Steele, Jackie L.

    2001-02-01

    This data package documents the experimentally derived input data on the representative waste glasses LAWABP1 and HLP-31 that will be used for simulations of the immobilized lowactivity waste disposal system with the Subsurface Transport Over Reactive Multiphases (STORM) code. The STORM code will be used to provide the near-field radionuclide release source term for a performance assessment to be issued in March of 2001. Documented in this data package are data related to 1) kinetic rate law parameters for glass dissolution, 2) alkali-H ion exchange rate, 3) chemical reaction network of secondary phases that form in accelerated weathering tests, and 4) thermodynamic equilibrium constants assigned to these secondary phases. The kinetic rate law and Na+-H+ ion exchange rate were determined from single-pass flow-through experiments. Pressurized unsaturated flow and vapor hydration experiments were used for accelerated weathering or aging of the glasses. The majority of the thermodynamic data were extracted from the thermodynamic database package shipped with the geochemical code EQ3/6. However, several secondary reaction products identified from laboratory tests with prototypical LAW glasses were not included in this database, nor are the thermodynamic data available in the open literature. One of these phases, herschelite, was determined to have a potentially significant impact on the release calculations and so a solubility product was estimated using a polymer structure model developed for zeolites. Although this data package is relatively complete, final selection of ILAW glass compositions has not been done by the waste treatment plant contractor. Consequently, revisions to this data package to address new ILAW glass formulations are to be regularly expected.

  9. Degradation of Sodium-Polyacrylate in Dilute Aqueous Solution

    NASA Astrophysics Data System (ADS)

    Saita, Takao

    1980-12-01

    It is shown using a capillary viscometer that the viscosity of a dilute aqueous solution of sodium-polyacrylate at 20°C decreases gradually for each flow time measurement and also decreases with the time of rest. Assuming that the polymer degradation is caused by shearing stress and oxidation, their effects are discussed with the data obtained using a closed-type capillary viscometer derived for this investigation. It is proved from the results that rupture of the Na-PAA molecule is caused by mechanochemical degradation, and also photo-degradation under the usual illumination and sunlight in a laboratory.

  10. Laboratory Information Systems.

    PubMed

    Henricks, Walter H

    2015-06-01

    Laboratory information systems (LISs) supply mission-critical capabilities for the vast array of information-processing needs of modern laboratories. LIS architectures include mainframe, client-server, and thin client configurations. The LIS database software manages a laboratory's data. LIS dictionaries are database tables that a laboratory uses to tailor an LIS to the unique needs of that laboratory. Anatomic pathology LIS (APLIS) functions play key roles throughout the pathology workflow, and laboratories rely on LIS management reports to monitor operations. This article describes the structure and functions of APLISs, with emphasis on their roles in laboratory operations and their relevance to pathologists.

  11. Chondritic Asteroids--When Did Aqueous Alteration Happen?

    NASA Astrophysics Data System (ADS)

    Doyle, P. M.

    2015-06-01

    Using a synthesized fayalite (Fe2SiO4) standard for improved 53Mn-53Cr radiometric age dating, Patricia Doyle (previously at the University of Hawaii and now at the University of Cape Town, South Africa) and coauthors from Hawaii, the National Astronomical Observatory of Japan, University of Chicago, and Lawrence Livermore National Laboratory in California, analyzed aqueously formed fayalite in the ordinary chondrite Elephant Moraine 90161 (L3.05) and in the carbonaceous chondrites Asuka 881317 (CV3) and MacAlpine Hills 88107 (CO3-like) from Antarctica. The data obtained indicate that liquid water existed - and aqueous alteration started - on the chondritic parent bodies about three million years earlier than previously determined. This discovery has implications for understanding when and where the asteroids accreted. The 53Mn-53Cr chronology of chondrite aqueous alteration, combined with thermodynamic calculations and physical modeling, signifies that hydrated asteroids, at least those sampled by meteorites, accreted in the inner Solar System (2-4 AU) near the main asteroid belt 2-4 million years after the beginning of the Solar System, rather than migrating inward after forming in the Solar System's colder, outer regions beyond Jupiter's present orbit (5-15 AU).

  12. “Towards building better linkages between aqueous phase ...

    EPA Pesticide Factsheets

    Currently, CMAQ’s aqueous phase chemistry routine (AQCHEM-base) assumes Henry’s Law equilibrium and employs a forward Euler method to solve a small set of oxidation equations, considering the additional processes of aitken scavenging and wet deposition in series and employing a bisection method to calculate H+ concentrations. With potentially hundreds of reactions that may be important in cloud water and only seven reactions in the current model, expansion of the existing mechanism is an important area of investigation. However, with the current mechanism hardwired into the solver code, the module is difficult to expand with additional chemistry. It also ignores the impacts of mass transfer limitations on cloud chemistry which may be significant. Here, the Kinetic PreProcessor has been applied to generate a Rosenbrock solver for the CMAQ v5.0.1 aqueous phase chemistry mechanism. The module has been updated to simultaneously solve kinetic mass transfer between the phases, dissociation/association, chemical kinetics, Aitken scavenging, and wet deposition. This will allow for easier expansion of the chemical mechanism in the future and a better link between aqueous phase chemistry and droplet microphysics. The National Exposure Research Laboratory (NERL) Atmospheric Modeling and Analysis Division (AMAD) conducts research in support of EPA mission to protect human health and the environment. AMAD research program is engaged in developing and evaluating pre

  13. Advanced oxidation of alkylphenol ethoxylates in aqueous systems.

    PubMed

    Nagarnaik, Pranav M; Boulanger, Bryan

    2011-10-01

    Alkylphenols and alkylphenol ethoxylates are ubiquitous wastewater contaminants. In this study the oxidation of nonylphenol ethoxylates (NPEO) and octylphenol ethoxylates (OPEO) by oxidant systems generating hydroxide radicals was evaluated. The reaction of each oxidant with a technical mixture of NPEO (Tergitol™) and OPEO (Triton X-100™) in ultrapure laboratory water and four aqueous environmental matrices was carried out in order to develop an understanding of reaction kinetics. The oxidation of APEOs was evaluated by hydroxyl radical generated by (1) hydrogen peroxide in the presence of ultraviolet light, (2) Fenton's reagent, and (3) a photo-Fenton's process. The second order kinetic rate constant for both NPEO and OPEO with hydroxyl radical was calculated to be 1.1×10¹⁰ M⁻¹ s⁻¹. The efficacy of the AOPs within an aqueous environmental matrix was dependent on the rate of formation of hydroxyl radical and the scavenging capacity of the matrix. A model based on the hydroxyl radical formation, scavenging capacity and the kinetic rate constant of target APEO was developed from the existing literature and applied to predict the concentration of APEOs in solution during advanced oxidation in different aqueous environmental matrices. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Thermosensitive aqueous solutions of polyvinylacetone

    NASA Astrophysics Data System (ADS)

    Wu, Wei-Tai; Wang, Yusong; Shi, Lei; Zhu, Qingren; Pang, Wenmin; Xu, Guoyong; Lu, Fei

    2006-04-01

    The dimethylketals of poly(vinyl alcohol), termed polyvinylacetone (PVKA), of moderate ketalization degree in the range from 0.28 to 0.6 exhibited temperature-induced phase transition in aqueous solution, as revealed by cloud point measurements and electron micrographs, which was then further investigated on molecular level using solution-state 1H NMR measurements. The present phase transition is caused by the amphiphilic characteristics in the polymer chain. Moreover, this finding could be further applied as a novel strategy in the syntheses of thermosensitive polymer by the hydrophobic functionalities of linear polyol.

  15. Supramolecular Polymers in Aqueous Media.

    PubMed

    Krieg, Elisha; Bastings, Maartje M C; Besenius, Pol; Rybtchinski, Boris

    2016-02-24

    This review discusses one-dimensional supramolecular polymers that form in aqueous media. First, naturally occurring supramolecular polymers are described, in particular, amyloid fibrils, actin filaments, and microtubules. Their structural, thermodynamic, kinetic, and nanomechanical properties are highlighted, as well as their importance for the advancement of biologically inspired supramolecular polymer materials. Second, five classes of synthetic supramolecular polymers are described: systems based on (1) hydrogen-bond motifs, (2) large π-conjugated surfaces, (3) host-guest interactions, (4) peptides, and (5) DNA. We focus on recent studies that address key challenges in the field, providing mechanistic understanding, rational polymer design, important functionality, robustness, or unusual thermodynamic and kinetic properties.

  16. Supercooling behavior in aqueous solutions.

    PubMed

    Kimizuka, Norihito; Suzuki, Toru

    2007-03-08

    Using the emulsion method, we measured the homogeneous nucleation temperature depression, DeltaT(f,hom), and equilibrium melting points depression, DeltaT(m), of various aqueous solutions and then calculated lambda for each solute using the linear relationship DeltaT(f,hom) = lambdaDeltaT(m). We defined lambda as the solute-specific supercooling capacity and examined its correlation with some known hydration characteristics. The results showed that lambda is correlated with D0, the self-diffusion coefficient of solute molecules in infinite dilution.

  17. CESIUM RECOVERY FROM AQUEOUS SOLUTIONS

    DOEpatents

    Schneider, R.A.

    1961-06-20

    Cesium may be precipitated from an aqueous solution whose acidity ranges between a pH of 1.5 and a molarity of 5 on cobaltous, zinc, cadmium, nickel, or ferrous cobalticyanide. This precipitation brings about a separation from most fission products. Ruthenium which coprecipitates to a great degree can be removed by dissolving in sulfuric acid and boiling the solution in the presence of periodic acid for volatilization; other coprecipitated fission products can then be precipitated from the sulfuric acid solution with a ferric hydroxide carrier.

  18. Road Transportable Analytical Laboratory (RTAL) system: Volume III, Appendices C through J. Final report

    SciTech Connect

    Finger, S.M.; De Avila, J.C.; Keith, V.F.

    1996-08-01

    The Road Transportable Analytical Laboratory (RTAL) provides a portabler laboratory for the analysis of soils, ground water, and surface water. This report presents data from a soils sample TCLP VOA and SVOA report, aqueous sample RCRA metals report, soils sample total and isotopic uranium report, SVOA sample analytical performance report, and and RCRA metal sample analytical performance report.

  19. Laboratory Animal Facilities. Laboratory Design Notes.

    ERIC Educational Resources Information Center

    Jonas, Albert M.

    1965-01-01

    Design of laboratory animal facilities must be functional. Accordingly, the designer should be aware of the complex nature of animal research and specifically the type of animal research which will be conducted in a new facility. The building of animal-care facilities in research institutions requires special knowledge in laboratory animal…

  20. Centrifugal contractors for laboratory-scale solvent extraction tests

    SciTech Connect

    Leonard, R.A.; Chamberlain, D.B.; Conner, C.

    1995-12-31

    A 2-cm contactor (minicontactor) was developed and used at Argonne National Laboratory for laboratory-scale testing of solvent extraction flowsheets. This new contactor requires only 1 L of simulated waste feed, which is significantly less than the 10 L required for the 4-cm unit that had previously been used. In addition, the volume requirements for the other aqueous and organic feeds are reduced correspondingly. This paper (1) discusses the design of the minicontactor, (2) describes results from having applied the minicontactor to testing various solvent extraction flowsheets, and (3) compares the minicontactor with the 4-cm contactor as a device for testing solvent extraction flowsheets on a laboratory scale.

  1. Materials Applications for Non-Lethal: Aqueous Foams

    SciTech Connect

    GOOLSBY,TOMMY D.; SCOTT,STEVEN H.

    1999-09-15

    High expansion aqueous foam is an aggregation of bubbles that has the appearance of soap suds and is used to isolate individuals both visually and acoustically. It was developed in the 1920's in England to fight coal mine fires and has been widely used since for fire fighting and dust suppression. It was developed at Sandia National Laboratories (SNL) in the 1970's for nuclear safeguards and security applications. In the mid-1990s, the National Institute of Justice (NIJ), the research arm of the Department of Justice, began a project with SNL to determine the applicability of high expansion aqueous foam for correctional applications. NIJ funded the project as part of its search for new and better less-than-lethal weapons for responding to violent and dangerous individuals, where other means of force could lead to serious injuries. The phase one objectives of the project were to select a low-to-no toxicity foam concentrate (foaming agent) with physical characteristics suited for use in a single cell or large prison disturbances, and to determine if the selected foam concentrate could serve as a carrier for Oleoresin Capsicum (OC) irritant. The phase two objectives were to conduct an extensive toxicology review of the selected foam concentrate and OC irritant, and to conduct respiration simulation experiments in the selected high expansion aqueous foam. The phase three objectives were to build a prototype individual cell aqueous foam system and to study the feasibility of aqueous foams for large prison facility disturbances. The phase four and five objectives were to use the prototype system to do large scale foam physical characteristics testing of the selected foam concentrate, and to have the prototype single cell system further evaluated by correctional representatives. Prison rather than street scenarios were evaluated as the first and most likely place for using the aqueous foam since prisons have recurrent incidents where officers and inmates might be

  2. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-2000 Status Report

    SciTech Connect

    Herbst, A.K.; McCray, J.A.; Kirkham, R.J.; Pao, J.; Argyle, M.D.; Lauerhass, L.; Bendixsen, C.L.; Hinckley, S.H.

    2000-10-31

    The Low-Activity Waste Process Technology Program anticipated that grouting will be used for disposal of low-level and transuranic wastes generated at the Idaho Nuclear Technology Engineering Center (INTEC). During fiscal year 2000, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed using silica gel and other absorbents to solidify sodium-bearing wastes. A feasibility study and conceptual design were completed for the construction of a grout pilot plant for simulated wastes and demonstration facility for actual wastes.

  3. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-2000 Status Report

    SciTech Connect

    Herbst, Alan Keith; Mc Cray, John Alan; Kirkham, Robert John; Pao, Jenn Hai; Argyle, Mark Don; Lauerhass, Lance; Bendixsen, Carl Lee; Hinckley, Steve Harold

    2000-11-01

    The Low-Activity Waste Process Technology Program anticipated that grouting will be used for disposal of low-level and transuranic wastes generated at the Idaho Nuclear Technology Engineering Center (INTEC). During fiscal year 2000, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed using silica gel and other absorbents to solidify sodium-bearing wastes. A feasibility study and conceptual design were completed for the construction of a grout pilot plant for simulated wastes and demonstration facility for actual wastes.

  4. Refining prostate seed brachytherapy: Comparing high-, intermediate-, and low-activity seeds for I-125 permanent seed prostate brachytherapy.

    PubMed

    Delouya, Guila; Bahary, Pascal; Carrier, Jean-François; Larouche, Renée-Xavière; Hervieux, Yannick; Béliveau-Nadeau, Dominic; Donath, David; Taussky, Daniel

    2015-01-01

    To analyze the difference in prostate coverage and dose to the rectum in men with prostate carcinoma treated with permanent seed brachytherapy with different seed activities. Forty-nine patients treated with iodine-125 permanent seed prostate brachytherapy with low-activity seeds of 0.30-0.37 mCi were identified. For each of these patients, 2 patients with similar prostate volume (±2 cc) were paired: one treated with intermediate seed activity (0.44-0.46 mCi) and one with high seed activity (0.60-0.66 mCi). The doses to prostate and rectum were compared using CT on Day 30. A total of 147 patients divided into the three seed activity groups were analyzed. Mean prostate volume was 35.7 cc (standard deviation [SD], 11.70). Compared with low-activity seeds, implants with high-activity seeds consisted of an average of 22 seeds and 4.7 needles less. The dose to the prostate (prostate volume receiving 100% of the prescribed dose [V100], prostate volume receiving 150% of the prescribed dose, and minimal dose covering 90% of the prostate volume expressed in Gy) was not higher on Day 30 (p = 0.58-0.97). The mean volume (in cubic centimeters) of rectal wall receiving 100% of the prescribed dose (V100) increased with activity: low activity, 0.34 cc (SD, 0.49), intermediate activity, 0.47 cc (SD, 0.48), and high activity, 0.72 cc (SD, 0.79) (p = 0.009). There was a trend (p = 0.073) toward a higher frequency of clinically unfavorable rectal dosimetry (V100 > 1.3 cc) in patients with high-activity seeds (16.7%) compared with low-activity (6.3%) or intermediate-activity (4.2%) seeds. High-activity seeds do not result in a higher dose to the prostate but in a higher dose to the rectum. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Charpy impact test results of four low activation ferritic alloys irradiated at 370{degrees}C to 15 DPA

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1996-10-01

    Miniature CVN specimens of four low activation ferritic alloys have been impact tested following irradiation at 370{degrees}C to 15 dpa. Comparison of the results with those of control specimens indicates that degradation in the impact behavior occurs in each of these four alloys. The 9Cr-2W alloy referred to as GA3X and the similar alloy F82H with 7.8Cr-2W appear most promising for further consideration as candidate structural materials in fusion energy system applications. These two alloys exhibit a small DBTT shift to higher temperatures but show increased absorbed energy on the upper shelf.

  6. Comparative evaluation of aqueous humor viscosity.

    PubMed

    Davis, Kyshia; Carter, Renee; Tully, Thomas; Negulescu, Ioan; Storey, Eric

    2015-01-01

    To evaluate aqueous humor viscosity in the raptor, dog, cat, and horse, with a primary focus on the barred owl (Strix varia). Twenty-six raptors, ten dogs, three cats, and one horse. Animals were euthanized for reasons unrelated to this study. Immediately, after horizontal and vertical corneal dimensions were measured, and anterior chamber paracentesis was performed to quantify anterior chamber volume and obtain aqueous humor samples for viscosity analysis. Dynamic aqueous humor viscosity was measured using a dynamic shear rheometer (AR 1000 TA Instruments, New Castle, DE, USA) at 20 °C. Statistical analysis included descriptive statistics, unpaired t-tests, and Tukey's test to evaluate the mean ± standard deviation for corneal diameter, anterior chamber volume, and aqueous humor viscosity amongst groups and calculation of Spearman's coefficient for correlation analyses. The mean aqueous humor viscosity in the barred owl was 14.1 centipoise (cP) ± 9, cat 4.4 cP ± 0.2, and dog 2.9 cP ± 1.3. The aqueous humor viscosity for the horse was 1 cP. Of the animals evaluated in this study, the raptor aqueous humor was the most viscous. The aqueous humor of the barred owl is significantly more viscous than the dog (P < 0.0001). The aqueous humor viscosity of the raptor, dog, cat, and horse can be successfully determined using a dynamic shear rheometer. © 2014 American College of Veterinary Ophthalmologists.

  7. Aqueous aerosol SOA formation: impact on aerosol physical properties.

    PubMed

    Woo, Joseph L; Kim, Derek D; Schwier, Allison N; Li, Ruizhi; McNeill, V Faye

    2013-01-01

    Organic chemistry in aerosol water has recently been recognized as a potentially important source of secondary organic aerosol (SOA) material. This SOA material may be surface-active, therefore potentially affecting aerosol heterogeneous activity, ice nucleation, and CCN activity. Aqueous aerosol chemistry has also been shown to be a potential source of light-absorbing products ("brown carbon"). We present results on the formation of secondary organic aerosol material in aerosol water and the associated changes in aerosol physical properties from GAMMA (Gas-Aerosol Model for Mechanism Analysis), a photochemical box model with coupled gas and detailed aqueous aerosol chemistry. The detailed aerosol composition output from GAMMA was coupled with two recently developed modules for predicting a) aerosol surface tension and b) the UV-Vis absorption spectrum of the aerosol, based on our previous laboratory observations. The simulation results suggest that the formation of oligomers and organic acids in bulk aerosol water is unlikely to perturb aerosol surface tension significantly. Isoprene-derived organosulfates are formed in high concentrations in acidic aerosols under low-NO(x) conditions, but more experimental data are needed before the potential impact of these species on aerosol surface tension may be evaluated. Adsorption of surfactants from the gas phase may further suppress aerosol surface tension. Light absorption by aqueous aerosol SOA material is driven by dark glyoxal chemistry and is highest under high-NO(x) conditions, at high relative humidity, in the early morning hours. The wavelength dependence of the predicted absorption spectra is comparable to field observations and the predicted mass absorption efficiencies suggest that aqueous aerosol chemistry can be a significant source of aerosol brown carbon under urban conditions.

  8. Environmental laboratory design

    SciTech Connect

    Newill, R.F.

    1996-11-01

    An effective, efficient laboratory building, operating at a reasonable cost within performance parameters set by the owner, determines quality control, employee morale and retention, operating costs, maintenance costs and renovation costs for the next thirty years. For better or worse, a new laboratory is managerial policy cast in stone. This paper, based on the author`s environmental laboratory design experience, offers an understanding of the relationship between costs, flexibility, function and quality in environmental laboratory design and construction. The comments are generally structured around publicly owned laboratories, with notes regarding private laboratories where appropriate.

  9. Theoretical study of decomposition of methanediol in aqueous solution.

    PubMed

    Inaba, Satoshi

    2015-06-04

    Methanediol is a product of the hydration of formaldehyde and is more abundant than formaldehyde in aqueous solution. We carried out a number of quantum chemical simulations to study the decomposition of methanediol in aqueous solution. The decomposition of a methanediol proceeds by transferring a proton from a hydroxyl to an oxygen atom of the other hydroxyl in the methanediol. The decomposition of the methanediol completes after the cleavage of the bond between the formaldehyde and the water molecule. The probability of the proton transfer increases by the quantum mechanical tunneling at the low temperature because the width of the potential barrier for the decomposition becomes similar to the de Broglie wavelength of the proton. We consider the catalytic effect of water molecules in aqueous solution. The structure of the methanediol is not required to change significantly when undergoing decomposition due to the active role of water molecules to transfer a proton. We consider three types of arrangement for water molecules with respect to a methanediol: (1) a ring structure formed by a methanediol and water molecules; (2) a water cluster attracted to a methanediol by hydrogen bonds; and (3) a water cluster and additional water molecules, both of which are attracted to a methanediol by hydrogen bonds. The activation energy for the decomposition is reduced by a water cluster more efficiently than water molecules in a ring structure. However, the activation energy reduced by a water cluster is still larger than that obtained from laboratory experiments. We include water molecules that are attracted to a methanediol by hydrogen bonds during the water-cluster-catalyzed decomposition of a methanediol. The hydrogen bonds with the water molecules permit little change in the structure of the methanediol during the decomposition and play a significant role to reduce the activation energy for the decomposition. The rate constant obtained from the theoretical simulation

  10. Allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala on three selected weed species

    NASA Astrophysics Data System (ADS)

    Ishak, Muhamad Safwan; Sahid, Ismail

    2014-09-01

    A laboratory experiment was conducted to study the allelopathic effects of the aqueous extract of the leaf and seed of Leucaena leucocephala. The aqueous extracts were individually tested on three selected weed species, namely goatweed (Ageratum conyzoides), coat buttons (Tridax procumbens) and lilac tasselflower (Emilia sonchifolia). The allelopathic effects of the leaf and seed extracts on germination, shoot length, root length and fresh weight of each of the selected weed species were determined. Germination of goatweed, coat buttons and lilac tasselflower were inhibited by the aqueous extracts of both the leaf and seed of L. leucocephala and was concentration dependent. Different concentrations of the aqueous extracts showed various germination patterns on the selected weeds species. Seedling length and fresh weight of goatweed, coat buttons and lilac tasselflower were reduced in response to respective increasing concentrations of the seed extracts. Maximum inhibition by the aqueous seed extract was observed more on the root rather than the shoot growth. The aqueous seed extract at T3 concentration reduced root length of goatweed, coat buttons and lilac tasselflower by 95%, 86% and 91% (of the control) respectively. The aqueous seed extract showed greater inhibitory effects than that of the aqueous leaf extract.

  11. Pulsatile flow into the aqueous veins: Manifestations in normal and glaucomatous eyes

    PubMed Central

    Johnstone, Murray; Martin, Elizabeth; Jamil, Annisa

    2015-01-01

    The aqueous outflow system is unique because nowhere else can the pattern of flow of an extravascular fluid be directly observed as it returns to the vascular system. Such observations reveal that aqueous flow both from Schlemm’s canal into the aqueous veins and from the aqueous veins into the episcleral veins is pulsatile. Pulsatile aqueous flow mechanisms are observable in vivo not only in normal and but also in glaucomatous eyes. A series of specific patterns accompany the pulsatile mixing of aqueous with blood in the episcleral veins. These directly observable patterns of pulsatile flow are synchronous with intraocular pressure (IOP) transients induced by the cardiac pulse, blinking and eye movement. Patterns of pulsatile flow are altered by events that increase IOP such as pressure on the side of the eye, tonography and water drinking. Pulsatile flow stops when IOP is reduced below its resting level, but begins again when IOP returns to the resting level. Pulsatile flow reduction probably results from the intrinsic reduction of pulse amplitude at a lower IOP, and may thus provide a passive mechanism to maintain short-term homeostasis. Thus modulation of the pulsatile flow phenomenon appears to maintain a homeostatic IOP setpoint. Visible pulsatile flow abnormalities develop in glaucoma patients. Medications that reduce IOP through improvement in outflow do so through pulsatile flow mechanisms. Laboratory studies have demonstrated that cyclic stresses in outflow tissues alter signaling pathways, cytoskeletal responses, extracellular matrix composition and cytokine secretion. How physiologic pulse transients orchestrate cellular responses and how cellular responses identified in the laboratory may in turn regulate pulsatile aqueous outflow is unknown. Linkage of laboratory and in vivo observations await an improved understanding of how cellular and extracellular structures within the outflow system are able to generate an aqueous pulse wave. The purpose of the

  12. Improved Superconducting properties in the Mg(11)B2 low activation superconductor prepared by low-temperature sintering.

    PubMed

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, M; Somer, M

    2016-05-05

    Mg(11)B2 has a great application prospect in the superconducting coils for fusion reactor as the "low activation superconductors". The un-doped Mg(11)B2 and Cu-doped Mg(11)B2 bulks using (11)B as a boron precursor were fabricated by low-temperature sintering in present work. It was found that the prepared Mg(11)B2 low activation superconductors exhibit better Jc performance than all of other Mg(11)B2 samples reported in previous studies. As for Cu doped Mg(11)B2, minor Cu addition can obviously improve the Mg(11)B2 grain crystallization and reduce the amount of MgO impurity. Hence, improved grain connectivity and higher Jc at low fields is obtained in Cu doped Mg(11)B2 samples. For un-doped samples, refined grains and more MgO impurity with proper size brought about more flux pinning centers, resulting in better Jc performance at high fields.

  13. DEVELOPMENT QUALIFICATION AND DISPOSAL OF AN ALTERNATIVE IMMOBILIZED LOW-ACTIVITY WASTE FORM AT THE HANFORD SITE

    SciTech Connect

    SAMS TL; EDGE JA; SWANBERG DJ; ROBBINS RA

    2011-01-13

    Demonstrating that a waste form produced by a given immobilization process is chemically and physically durable as well as compliant with disposal facility acceptance criteria is critical to the success of a waste treatment program, and must be pursued in conjunction with the maturation of the waste processing technology. Testing of waste forms produced using differing scales of processing units and classes of feeds (simulants versus actual waste) is the crux of the waste form qualification process. Testing is typically focused on leachability of constituents of concern (COCs), as well as chemical and physical durability of the waste form. A principal challenge regarding testing immobilized low-activity waste (ILAW) forms is the absence of a standard test suite or set of mandatory parameters against which waste forms may be tested, compared, and qualified for acceptance in existing and proposed nuclear waste disposal sites at Hanford and across the Department of Energy (DOE) complex. A coherent and widely applicable compliance strategy to support characterization and disposal of new waste forms is essential to enhance and accelerate the remediation of DOE tank waste. This paper provides a background summary of important entities, regulations, and considerations for nuclear waste form qualification and disposal. Against this backdrop, this paper describes a strategy for meeting and demonstrating compliance with disposal requirements emphasizing the River Protection Project (RPP) Integrated Disposal Facility (IDF) at the Hanford Site and the fluidized bed steam reforming (FBSR) mineralized low-activity waste (LAW) product stream.

  14. Improved Superconducting properties in the Mg11B2 low activation superconductor prepared by low-temperature sintering

    PubMed Central

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, M.; Somer, M.

    2016-01-01

    Mg11B2 has a great application prospect in the superconducting coils for fusion reactor as the “low activation superconductors”. The un-doped Mg11B2 and Cu-doped Mg11B2 bulks using 11B as a boron precursor were fabricated by low-temperature sintering in present work. It was found that the prepared Mg11B2 low activation superconductors exhibit better Jc performance than all of other Mg11B2 samples reported in previous studies. As for Cu doped Mg11B2, minor Cu addition can obviously improve the Mg11B2 grain crystallization and reduce the amount of MgO impurity. Hence, improved grain connectivity and higher Jc at low fields is obtained in Cu doped Mg11B2 samples. For un-doped samples, refined grains and more MgO impurity with proper size brought about more flux pinning centers, resulting in better Jc performance at high fields. PMID:27149682

  15. Sintering process and critical current density of low activation Mg11B2 superconductors from low temperature to high temperature

    NASA Astrophysics Data System (ADS)

    Cheng, Fang; Liu, Yongchang; Ma, Zongqing; Shahriar Al Hossain, Md; Somer, M.

    2016-08-01

    As the "low activation" superconductor, Mg11B2 has a potential application in superconducting coils for fusion reactor. In present work, the sintering process and critical current density of low activation Mg11B2 superconductors were systemically studied from low temperature to high temperature. It was found that the Jc and Hirr values of Mg11B2 bulks in present work are both obviously higher than that of those samples prepared in previous studies. Furthermore, the low-temperature sintered samples exhibit better Jc performance at high fields than the high-temperature sintered samples, due to strong grain boundaries pinning. On the other hand, the high-temperature sintered samples have higher Jc at low fields compared to low-temperature sintered samples, mainly owing to their better crystallinity and grain connectivity. The highest Jc value (2.20 ×105 A cm-2 at 20 K, self-field) is obtained in the Mg11B2 sample sintered at 850 °C for 45 min.

  16. Superfund Contract Laboratory Program

    EPA Pesticide Factsheets

    The Contract Laboratory Program (CLP) is a national network of EPA personnel, commercial laboratories, and support contractors whose primary mission is to provide data of known and documented quality to the Superfund program.

  17. The Microscale Laboratory.

    ERIC Educational Resources Information Center

    Zipp, Arden P.

    1990-01-01

    The materials needed and the procedures used in three microscale chemical laboratory experiments are detailed. Included are a microscale organic synthesis, a two-step synthetic sequence for the microscale organic laboratory, and a small-scale equilibrium experiment. (CW)

  18. [Laboratory of Biopolymer Compounds].

    PubMed

    Ostapchuk, A M

    2008-01-01

    General information is presented concerning the Laboratory of Biological Polymeric Compounds at the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine; equipment, analytical and biophysical methods applied in the laboratory are listed.

  19. An Electronics "Unit Laboratory"

    ERIC Educational Resources Information Center

    Davies, E. R.; Penton, S. J.

    1976-01-01

    Describes a laboratory teaching technique in which a single topic (in this case, bipolar junction transistors) is studied over a period of weeks under the supervision of one staff member, who also designs the laboratory work. (MLH)

  20. Tethered gravity laboratories study

    NASA Technical Reports Server (NTRS)

    Lucchetti, F.

    1989-01-01

    Tethered gravity laboratories study is presented. The following subject areas are covered: variable gravity laboratory; attitude tether stabilizer; configuration analysis (AIT); dynamic analysis (SAO); and work planned for the next reporting period.

  1. The Microscale Laboratory.

    ERIC Educational Resources Information Center

    Zipp, Arden P.

    1990-01-01

    The materials needed and the procedures used in three microscale chemical laboratory experiments are detailed. Included are a microscale organic synthesis, a two-step synthetic sequence for the microscale organic laboratory, and a small-scale equilibrium experiment. (CW)

  2. An Electronics "Unit Laboratory"

    ERIC Educational Resources Information Center

    Davies, E. R.; Penton, S. J.

    1976-01-01

    Describes a laboratory teaching technique in which a single topic (in this case, bipolar junction transistors) is studied over a period of weeks under the supervision of one staff member, who also designs the laboratory work. (MLH)

  3. Environmental Response Laboratory Network (ERLN) Laboratory Requirements

    EPA Pesticide Factsheets

    The Environmental Response Laboratory Network requires its member labs follow specified quality systems, sample management, data reporting, and general, in order to ensure consistent analytical data of known and documented quality.

  4. Aqueous photooxidation of ambient Po Valley Italy air samples: Insights into secondary organic aerosol formation

    NASA Astrophysics Data System (ADS)

    Kirkland, J. R.; Lim, Y. B.; Sullivan, A. P.; Decesari, S.; Facchini, C.; Collett, J. L.; Keutsch, F. N.; Turpin, B. J.

    2012-12-01

    In this work, we conducted aqueous photooxidation experiments with ambient samples in order to develop insights concerning the formation of secondary organic aerosol through gas followed by aqueous chemistry (SOAaq). Water-soluble organics (e.g., glyoxal, methylglyoxal, glycolaldehyde, acetic acid, acetone) are formed through gas phase oxidation of alkene and aromatic emissions of anthropogenic and biogenic origin. Their further oxidation in clouds, fogs and wet aerosols can form lower volatility products (e.g., oligomers, organic acids) that remain in the particle phase after water evaporation, thus producing SOA. The aqueous OH radical oxidation of several individual potentially important precursors has been studied in the laboratory. In this work, we used a mist-chamber apparatus to collect atmospheric mixtures of water-soluble gases from the ambient air at San Pietro Capofiume, Italy during the PEGASOS field campaign. We measured the concentration dynamics after addition of OH radicals, in order to develop new insights regarding formation of SOA through aqueous chemistry. Specifically, batch aqueous reactions were conducted with 33 ml mist-chamber samples (TOC ~ 50-100μM) and OH radicals (~10-12M) in a new low-volume aqueous reaction vessel. OH radicals were formed in-situ, continuously by H2O2 photolysis. Products were analyzed by ion chromatography (IC), electrospray ionization mass spectrometry (ESI-MS +/-), and ESI-MS with IC pre-separation (IC/ESI-MS-). Reproducible formation of pyruvate and oxalate were observed both by IC and ESI-MS. These compounds are known to form from aldehyde oxidation in the aqueous phase. New insights regarding the aqueous chemistry of these "more atmospherically-realistic" experiments will be discussed.

  5. EPA Environmental Chemistry Laboratory

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Environmental Protection Agency's (EPA) Chemistry Laboratory (ECL) is a national program laboratory specializing in residue chemistry analysis under the jurisdiction of the EPA's Office of Pesticide Programs in Washington, D.C. At Stennis Space Center, the laboratory's work supports many federal anti-pollution laws. The laboratory analyzes environmental and human samples to determine the presence and amount of agricultural chemicals and related substances. Pictured, ECL chemists analyze environmental and human samples for the presence of pesticides and other pollutants.

  6. Employment at National Laboratories

    SciTech Connect

    E. S. Peterson; C. A. Allen

    2007-04-01

    Scientists enter the National Laboratory System for many different reasons. For some, faculty positions are scarce, so they take staff-scientist position at national laboratories (i.e. Pacific Northwest, Idaho, Los Alamos, and Brookhaven). Many plan to work at the National Laboratory for 5 to 7 years and then seek an academic post. For many (these authors included), before they know it it’s 15 or 20 years later and they never seriously considered leaving the laboratory system.

  7. EPA Environmental Chemistry Laboratory

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Environmental Protection Agency's (EPA) Chemistry Laboratory (ECL) is a national program laboratory specializing in residue chemistry analysis under the jurisdiction of the EPA's Office of Pesticide Programs in Washington, D.C. At Stennis Space Center, the laboratory's work supports many federal anti-pollution laws. The laboratory analyzes environmental and human samples to determine the presence and amount of agricultural chemicals and related substances. Pictured, ECL chemists analyze environmental and human samples for the presence of pesticides and other pollutants.

  8. A laboratory perspective on environmental laboratory certification

    SciTech Connect

    Herdlick, M.J.

    1996-11-01

    With the approach of the end of the millennium, one issue stands at the forefront in the minds of politicians, scholars, and the world in general: The constant need and desire to protect, to beautify, and to heal the environment and the earth`s resources. A crucial and integral part of this plan is the environmental testing laboratory which, for the most part, bursted into existence with the formation of the United States Environmental Protection Agency in the 1970`s. The need for good quality labs is an on-going concern since the federal and state regulations are constantly in a state of flux. Just like any other business sector, the laboratory is monitored by its peer groups including its respective clients, state authorities, and regional EPA personnel through the process of accreditation and certification. Unfortunately, the laboratory certification program for environmental laboratories is a complicated process since no true national program exists that blankets the entire regulatory dilemma. It is the purpose of my poster session to discuss the current state of the formal laboratory certification process for a typical testing laboratory that operates in many states for a wide variety of clients.

  9. Theme: Laboratory Instruction.

    ERIC Educational Resources Information Center

    Bruening, Thomas H.; And Others

    1992-01-01

    A series of theme articles discuss setting up laboratory hydroponics units, the school farm at the Zuni Pueblo in New Mexico, laboratory experiences in natural resources management and urban horticulture, the development of teaching labs at Derry (PA) High School, management of instructional laboratories, and industry involvement in agricultural…

  10. LABORATORY-ACQUIRED MYCOSES

    DTIC Science & Technology

    laboratory- acquired mycoses . Insofar as possible, the etiological fungus, type of laboratory, classification of personnel, type of work conducted, and other...pertinent data have been listed in this study. More than 288 laboratory- acquired mycoses are described here, including 108 cases of

  11. Echocardiography laboratory accreditation.

    PubMed

    Katanick, S L

    1998-01-01

    In response to the need for standardization and improvement in the quality of echocardiographic laboratories an intersocietal commission has been created. The intent of the accreditation process is designed to recognize laboratories that provide quality services and to be used as an educational tool to improve the overall quality of the laboratory.

  12. The Language Laboratory.

    ERIC Educational Resources Information Center

    Claudel, Calvin Andre

    A general review of the development of the language laboratory is given in this article in the light of claims made by early theorists favoring the use of the laboratory in foreign language instruction. Comments are directed to the nature of language, language teaching methodology, and use and criticism of the laboratory. The author concludes that…

  13. Undergraduate Chemistry Laboratory

    ERIC Educational Resources Information Center

    Bretz, Stacey Lowery; Fay, Michael; Bruck, Laura B.; Towns, Marcy H.

    2013-01-01

    Forty chemistry faculty from American Chemical Society-approved departments were interviewed to determine their goals for undergraduate chemistry laboratory. Faculty were stratified by type of institution, departmental success with regard to National Science Foundation funding for laboratory reform, and level of laboratory course. Interview…

  14. Theme: Laboratory Instruction.

    ERIC Educational Resources Information Center

    Bruening, Thomas H.; And Others

    1992-01-01

    A series of theme articles discuss setting up laboratory hydroponics units, the school farm at the Zuni Pueblo in New Mexico, laboratory experiences in natural resources management and urban horticulture, the development of teaching labs at Derry (PA) High School, management of instructional laboratories, and industry involvement in agricultural…

  15. Laboratory Activities in Israel

    ERIC Educational Resources Information Center

    Mamlok-Naaman, Rachel; Barnea, Nitza

    2012-01-01

    Laboratory activities have long had a distinctive and central role in the science curriculum, and science educators have suggested that many benefits accrue from engaging students in science laboratory activities. Many research studies have been conducted to investigate the educational effectiveness of laboratory work in science education in…

  16. Good Laboratory Practice

    NASA Astrophysics Data System (ADS)

    Hadjicostas, Evsevios

    The principles of Good Laboratory Practice (GLP) in conjunction with the principles of Total Quality Management (see chapter 6) ensure the quality and reliability of the laboratory results, which in turn help to ensure the protection of the environment and human health and safety. A step further is the accreditation of laboratories to ISO 17025 (see chapter 2) to perform specified activities.

  17. Los Alamos National Laboratory.

    ERIC Educational Resources Information Center

    Hammel, Edward F., Jr.

    1982-01-01

    Current and post World War II scientific research at the Los Alamos National Laboratory (New Mexico) is discussed. The operation of the laboratory, the Los Alamos consultant program, and continuation education, and continuing education activities at the laboratory are also discussed. (JN)

  18. Improving Laboratory Efficiency.

    ERIC Educational Resources Information Center

    Shively, Michael Jay

    1979-01-01

    Factors that influence the efficiency of laboratory experiences include: size of laboratory group, length of session, discussion, special tools, and applications of knowledge learned. It is suggested that these variables may be altered to insure that students gain from their time spent in the laboratory. (BH)

  19. Los Alamos National Laboratory.

    ERIC Educational Resources Information Center

    Hammel, Edward F., Jr.

    1982-01-01

    Current and post World War II scientific research at the Los Alamos National Laboratory (New Mexico) is discussed. The operation of the laboratory, the Los Alamos consultant program, and continuation education, and continuing education activities at the laboratory are also discussed. (JN)

  20. Laboratory Ventilation and Safety.

    ERIC Educational Resources Information Center

    Steere, Norman V.

    1965-01-01

    In order to meet the needs of both safety and economy, laboratory ventilation systems must effectively remove air-borne toxic and flammable materials and at the same time exhaust a minimum volume of air. Laboratory hoods are the most commonly used means of removing gases, dusts, mists, vapors, and fumed from laboratory operations. To be effective,…

  1. Laboratory Activities in Israel

    ERIC Educational Resources Information Center

    Mamlok-Naaman, Rachel; Barnea, Nitza

    2012-01-01

    Laboratory activities have long had a distinctive and central role in the science curriculum, and science educators have suggested that many benefits accrue from engaging students in science laboratory activities. Many research studies have been conducted to investigate the educational effectiveness of laboratory work in science education in…

  2. Undergraduate Chemistry Laboratory

    ERIC Educational Resources Information Center

    Bretz, Stacey Lowery; Fay, Michael; Bruck, Laura B.; Towns, Marcy H.

    2013-01-01

    Forty chemistry faculty from American Chemical Society-approved departments were interviewed to determine their goals for undergraduate chemistry laboratory. Faculty were stratified by type of institution, departmental success with regard to National Science Foundation funding for laboratory reform, and level of laboratory course. Interview…

  3. Laboratory-acquired Brucellosis

    PubMed Central

    Gallo, Richard; Kelly, Molly; Limberger, Ronald J.; DeAngelis, Karen; Cain, Louise; Wallace, Barbara; Dumas, Nellie

    2004-01-01

    We report two laboratory-acquired Brucella melitensis infections that were shown to be epidemiologically related. Blood culture isolates were initially misidentified because of variable Gram stain results, which led to misdiagnoses and subsequent laboratory exposures. Notifying laboratory personnel who unknowingly processed cultures from brucellosis patients is an important preventive measure. PMID:15504276

  4. REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS

    DOEpatents

    Schulz, W.W.

    1959-08-01

    The removal of chlorides from aqueons solutions is described. The process involves contacting the aqueous chloride containing solution with a benzene solution about 0.005 M in phenyl mercuric acetate whereby the chloride anions are taken up by the organic phase and separating the organic phase from the aqueous solutions.

  5. SEPARATION OF RUTHENIUM FROM AQUEOUS SOLUTIONS

    DOEpatents

    Beederman, M.; Vogler, S.; Hyman, H.H.

    1959-07-14

    The separation of rathenium from a rathenium containing aqueous solution is described. The separation is accomplished by adding sodium nitrite, silver nitrate and ozone to the ruthenium containing aqueous solution to form ruthenium tetroxide and ihen volatilizing off the ruthenium tetroxide.

  6. ENGINEERING BULLETIN: AIR STRIPPING OF AQUEOUS SOLUTIONS

    EPA Science Inventory

    Air striding is a means to transfer contaminants from aqueous solutions to air. ontaminants are not destroyed by air stripping but are physically separated from the aqueous solutions. ontaminant vapors are transferred into the air stream and, if necessary, can be treated by incin...

  7. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent by...

  8. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent by...

  9. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent by...

  10. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent by...

  11. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent by...

  12. ENGINEERING BULLETIN: AIR STRIPPING OF AQUEOUS SOLUTIONS

    EPA Science Inventory

    Air striding is a means to transfer contaminants from aqueous solutions to air. ontaminants are not destroyed by air stripping but are physically separated from the aqueous solutions. ontaminant vapors are transferred into the air stream and, if necessary, can be treated by incin...

  13. Laboratory Simulations of Mars Evaporite Geochemistry

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey M.; Bullock, Mark A.; Newsom, Horton; Nelson, Melissa

    2010-01-01

    Evaporite-rich sedimentary deposits on Mars were formed under chemical conditions quite different from those on Earth. Their unique chemistries record the chemical and aqueous conditions under which they were formed and possibly subsequent conditions to which they were subjected. We have produced evaporite salt mineral suites in the laboratory under two simulated Martian atmospheres: (1) present-day and (2) a model of an ancient Matian atmosphere rich in volcanic gases. The composition of these synthetic Mars evaporites depends on the atmospheres under which they were desiccated as well as the chemistries of their precursor brines. In this report, we describe a Mars analog evaporite laboratory apparatus and the experimental methods we used to produce and analyze the evaporite mineral suites.

  14. Dynamics of Aqueous Foam Drops

    NASA Technical Reports Server (NTRS)

    Akhatov, Iskander; McDaniel, J. Gregory; Holt, R. Glynn

    2001-01-01

    We develop a model for the nonlinear oscillations of spherical drops composed of aqueous foam. Beginning with a simple mixture law, and utilizing a mass-conserving bubble-in-cell scheme, we obtain a Rayleigh-Plesset-like equation for the dynamics of bubbles in a foam mixture. The dispersion relation for sound waves in a bubbly liquid is then coupled with a normal modes expansion to derive expressions for the frequencies of eigenmodal oscillations. These eigenmodal (breathing plus higher-order shape modes) frequencies are elicited as a function of the void fraction of the foam. A Mathieu-like equation is obtained for the dynamics of the higher-order shape modes and their parametric coupling to the breathing mode. The proposed model is used to explain recently obtained experimental data.

  15. Photochemical processing of aqueous atmospheric brown carbon

    NASA Astrophysics Data System (ADS)

    Zhao, R.; Lee, A. K. Y.; Huang, L.; Li, X.; Yang, F.; Abbatt, J. P. D.

    2015-01-01

    Atmospheric Brown Carbon (BrC) is a collective term for light absorbing organic compounds in the atmosphere. While the identification of BrC and its formation mechanisms is currently a central effort in the community, little is known about the atmospheric removal processes of aerosol BrC. As a result, we report a series of laboratory studies of photochemical processing of BrC in the aqueous phase, by direct photolysis and OH oxidation. Solutions of ammonium sulfate mixed with glyoxal (GLYAS) or methylglyoxal (MGAS) are used as surrogates for a class of secondary BrC mediated by imine intermediates. Three nitrophenol species, namely 4-nitrophenol, 5-nitroguaiacol and 4-nitrocatechol, were investigated as a class of water soluble BrC originating from biomass burning. Photochemical processing induced significant changes in the absorptive properties of BrC. The imine-mediated BrC solutions exhibited rapid photo-bleaching with both direct photolysis and OH oxidation, with atmospheric half-lives of minutes to a few hours. The nitrophenol species exhibited photo-enhancement in the visible range during direct photolysis and the onset of OH oxidation, but rapid photo-bleaching was induced by further OH exposure on an atmospheric timescale of an hour or less. To illustrate atmospheric relevance of this work, we also performed direct photolysis experiments on water soluble organic carbon extracted from biofuel combustion samples and observed rapid changes in optical properties of these samples as well. Overall, these experiments indicate that atmospheric models need to incorporate representations of atmospheric processing of BrC species to accurately model their radiative impacts.

  16. Photochemical processing of aqueous atmospheric brown carbon

    NASA Astrophysics Data System (ADS)

    Zhao, R.; Lee, A. K. Y.; Huang, L.; Li, X.; Yang, F.; Abbatt, J. P. D.

    2015-06-01

    Atmospheric brown carbon (BrC) is a collective term for light absorbing organic compounds in the atmosphere. While the identification of BrC and its formation mechanisms is currently a central effort in the community, little is known about the atmospheric removal processes of aerosol BrC. As a result, we report on a series of laboratory studies of photochemical processing of BrC in the aqueous phase, by direct photolysis and OH oxidation. Solutions of ammonium sulfate mixed with glyoxal (GLYAS) or methylglyoxal (MGAS) are used as surrogates for a class of secondary BrC mediated by imine intermediates. Three nitrophenol species, namely 4-nitrophenol, 5-nitroguaiacol and 4-nitrocatechol, were investigated as a class of water-soluble BrC originating from biomass burning. Photochemical processing induced significant changes in the absorptive properties of BrC. The imine-mediated BrC solutions exhibited rapid photo-bleaching with both direct photolysis and OH oxidation, with atmospheric half-lives of minutes to a few hours. The nitrophenol species exhibited photo-enhancement in the visible range during direct photolysis and the onset of OH oxidation, but rapid photo-bleaching was induced by further OH exposure on an atmospheric timescale of an hour or less. To illustrate the atmospheric relevance of this work, we also performed direct photolysis experiments on water-soluble organic carbon extracted from biofuel combustion samples and observed rapid changes in the optical properties of these samples as well. Overall, these experiments indicate that atmospheric models need to incorporate representations of atmospheric processing of BrC species to accurately model their radiative impacts.

  17. Low-activation-energy conduction in polycrystalline. cap alpha. -Al/sub 2/O/sub 3/ doped with Si and Na

    SciTech Connect

    Lee, C.H.; Kroger, F.A.

    1985-02-01

    Polycrystalline Al/sub 2/O/sub 3/ containing a glassy aluminosilicate second phase displays a low-activation-energy conductivity when Na is present. The conductivity is ionic in nature at high oxygen pressure and electronic at low oxygen pressure and is attributed to the migration of Na/sup +/ ions and electrons through the second phase present at triple junctions. A smaller lowactivation-energy conductivity is found in the absence of sodium, but in that case the low-activation-energy branch has different properties. Al/sub 2/O/sub 3/:Na without silicon has no lowtemperature low-activation-energy branch.

  18. Metal separations using aqueous biphasic partitioning systems

    SciTech Connect

    Chaiko, D.J.; Zaslavsky, B.; Rollins, A.N.; Vojta, Y.; Gartelmann, J.; Mego, W.

    1996-05-01

    Aqueous biphasic extraction (ABE) processes offer the potential for low-cost, highly selective separations. This countercurrent extraction technique involves selective partitioning of either dissolved solutes or ultrafine particulates between two immiscible aqueous phases. The extraction systems that the authors have studied are generated by combining an aqueous salt solution with an aqueous polymer solution. They have examined a wide range of applications for ABE, including the treatment of solid and liquid nuclear wastes, decontamination of soils, and processing of mineral ores. They have also conducted fundamental studies of solution microstructure using small angle neutron scattering (SANS). In this report they review the physicochemical fundamentals of aqueous biphase formation and discuss the development and scaleup of ABE processes for environmental remediation.

  19. Mukaiyama Aldol Reactions in Aqueous Media

    PubMed Central

    Kitanosono, Taku; Kobayashi, Shū

    2013-01-01

    Mukaiyama aldol reactions in aqueous media have been surveyed. While the original Mukaiyama aldol reactions entailed stoichiometric use of Lewis acids in organic solvents under strictly anhydrous conditions, Mukaiyama aldol reactions in aqueous media are not only suitable for green sustainable chemistry but are found to produce singular phenomena. These findings led to the discovery of a series of water-compatible Lewis acids such as lanthanide triflates in 1991. Our understanding on these beneficial effects in the presence of water will be deepened through the brilliant examples collected in this review. 1 Introduction 2 Rate Enhancement by Water in the Mukaiyama Aldol Reaction 3 Lewis Acid Catalysis in Aqueous or Organic Solvents 3.1 Water-Compatible Lewis Acids 4 Lewis-Base Catalysis in Aqueous or Organic Solvents 5 The Mukaiyama Aldol Reactions in 100% Water 6 Asymmetric Catalysts in Aqueous Media and Water 7 Conclusions and Perspective PMID:24971045

  20. Laboratory Turnaround Time

    PubMed Central

    Hawkins, Robert C

    2007-01-01

    Turnaround time (TAT) is one of the most noticeable signs of laboratory service and is often used as a key performance indicator of laboratory performance. This review summarises the literature regarding laboratory TAT, focusing on the different definitions, measures, expectations, published data, associations with clinical outcomes and approaches to improve TAT. It aims to provide a consolidated source of benchmarking data useful to the laboratory in setting TAT goals and to encourage introduction of TAT monitoring for continuous quality improvement. A 90% completion time (sample registration to result reporting) of <60 minutes for common laboratory tests is suggested as an initial goal for acceptable TAT. PMID:18392122

  1. Underground laboratory in China

    NASA Astrophysics Data System (ADS)

    Chen, Heshengc

    2012-09-01

    The underground laboratories and underground experiments of particle physics in China are reviewed. The Jinping underground laboratory in the Jinping mountain of Sichuan, China is the deepest underground laboratory with horizontal access in the world. The rock overburden in the laboratory is more than 2400 m. The measured cosmic-ray flux and radioactivities of the local rock samples are very low. The high-purity germanium experiments are taking data for the direct dark-matter search. The liquid-xenon experiment is under construction. The proposal of the China National Deep Underground Laboratory with large volume at Jinping for multiple discipline research is discussed.

  2. Skylab mobile laboratory

    NASA Technical Reports Server (NTRS)

    Primeaux, G. R.; Larue, M. A.

    1975-01-01

    The Skylab mobile laboratory was designed to provide the capability to obtain necessary data on the Skylab crewmen 30 days before lift-off, within 1 hour after recovery, and until preflight physiological baselines were reattained. The mobile laboratory complex consisted of six laboratories that supported cardiovascular, metabolic, nutrition and endocrinology, operational medicine, blood, and microbiology experiments; a utility package; and two shipping containers. The objectives and equipment requirements of the Skylab mobile laboratory and the data acquisition systems are discussed along with processes such as permanently mounting equipment in the individual laboratories and methods of testing and transporting the units. The operational performance, in terms of amounts of data collected, and the concept of mobile laboratories for medical and scientific experiments are evaluated. The Skylab mobile laboratory succeeded in facilitating the data collection and sample preservation associated with the three Skylab manned flights.

  3. Low activated incore instrument

    DOEpatents

    Ekeroth, D.E.

    1994-04-19

    Instrumentation is described for nuclear reactor head-mounted incore instrumentation systems fabricated of low nuclear cross section materials (i.e., zirconium or titanium). The instrumentation emits less radiation than that fabricated of conventional materials. 9 figures.

  4. Low activated incore instrument

    DOEpatents

    Ekeroth, Douglas E.

    1994-01-01

    Instrumentation for nuclear reactor head-mounted incore instrumentation systems fabricated of low nuclear cross section materials (i.e., zirconium or titanium). The instrumentation emits less radiation than that fabricated of conventional materials.

  5. Further Charpy impact test results of low activation ferritic alloys, irradiated at 430{degrees}C to 67 dpa

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1997-04-01

    Miniature CVN specimens of four ferritic alloys, GA3X, F82H, GA4X and HT9, have been impact tested following irradiation at 430{degrees}C to 67 dpa. Comparison of the results with those of the previously tested lower dose irradiation condition indicates that the GA3X and F82H alloys, two primary candidate low activation alloys, exhibit virtually identical behavior following irradiation at 430{degrees}C to {approximately}67 dpa and at 370{degrees}C to {approximately}15 dpa. Very little shift is observed in either DBTT or USE relative to the unirradiated condition. The shifts in DBTT and USE observed in both GA4X and HT9 were smaller after irradiation at 430{degrees}C to {approximately}67 dpa than after irradiation at 370{degrees}C to {approximately}15 dpa.

  6. MECHANICAL PROPERTIES AND MICROSTRUCTURE IN LOW ACTIVATION MARTENSITIC STEELS F82H AND OPTIMAX AFTER 800 MEV PROTON IRRADIATION

    SciTech Connect

    Y. DAI; ET AL

    1999-10-01

    Low-activation martensitic steels, F82H (mod.) and Optimax-A, have been irradiated with 800-MeV protons up to 5.9 dpa. The tensile properties and microstructure have been studied. The results show that radiation hardening increases continuously with irradiation dose. F82H has lesser irradiation hardening as compared to Optimax-A in the present work and DIN1.4926 from a previous study. The irradiation embrittlement effects are evident in the materials since the uniform elongation is reduced sharply to less than 2%. However, all the irradiated samples ruptured in a ductile-fracture mode. Defect clusters have been observed. The size and the density of defect clusters increase with the irradiation dose. Precipitates are amorphous after irradiation.

  7. Chemical segregation behavior under thermal aging of the low-activation F82H-modified steel

    NASA Astrophysics Data System (ADS)

    Lapeña, J.; Garcia-Mazario, M.; Fernández, P.; Lancha, A. M.

    2000-12-01

    In this work, thermal aging of the low-activation F82H-modified steel has been performed at temperatures in the range 300-600°C during periods up to 5000 h. A detailed mechanical and microstructural characterization has been carried out in the aged materials, as well as in the as-received state material for reference. Auger electron spectroscopy (AES) analysis has been performed for these materials to study the microchemistry at the grain boundaries. The results show a decrease of the impact properties after aging at 600°C that has been related to the precipitation of the Laves phase. Auger analyses show chromium enrichment and iron depletion at grain boundaries in all material conditions. In addition, sulphur and tungsten have been observed by this technique at grain boundaries, their presence and distribution being dependent on the material state.

  8. DESIGN OF THE DEMOSNTRATION BULK VITRIFICATION SYSTEM FOR THE SUPPLEMENTAL TREATMENT OF LOW ACTIVITY TANK WASTE AT HANFORD

    SciTech Connect

    VAN BEEK JE

    2008-02-14

    In June 2004, the Demonstration Bulk Vitrification System (DBVS) was initiated with the intent to design, construct, and operate a full-scale bulk vitrification pilot-plant to treat low-activity tank waste from Hanford Tank 241-S-109. The DBVS facility uses In-Container Vitrification{trademark} (ICV{trademark}) at the core of the treatment process. The basic process steps combine liquid low-activity waste (LAW) and glassformers; dry the mixture; and then vitrify the mixture in a batch feed-while-melt process in a refractory lined steel container. Off-gases are processed through a state-of-the-art air pollution control system including sintered-metal filtration, thermal oxidation, acid gas scrubbing, and high-efficiency particulate air (HEPA) and high-efficiency gas adsorber (HEGA) filtration. Testing has focused on development and validation of the waste dryer, ICV, and sintered-metal filters (SMFs) equipment, operations enhancements, and glass formulation. With a parallel testing and design process, testing has allowed improvements to the DBVS equipment configuration and operating methodology, since its original inception. Design improvements include optimization of refractory panels in the ICV, simplifying glassformer addition equipment, increasing the number of waste feed chutes to the ICV, and adding capability for remote clean-out of piping, In addition, the U.S. Department of Energy (DOE) has provided an independent review of the entire DBVS process. While the review did not find any fatal flaws, some technical issues were identified that required a re-evaluation of the DBVS design and subsequent changes to the design. A 100 percent design package for the pilot plant will be completed and submitted to DOE for review in early 2008 that incorporates process improvements substantiated through testing and reviews. This paper provides a description of the bulk vitrification process and a discussion of major equipment design changes that have occurred based on full

  9. When comets get old: A synthesis of comet and meteor observations of the low activity comet 209P/LINEAR

    NASA Astrophysics Data System (ADS)

    Ye (叶泉志), Quan-Zhi; Hui (许文韬), Man-To; Brown, Peter G.; Campbell-Brown, Margaret D.; Pokorný, Petr; Wiegert, Paul A.; Gao (高兴), Xing

    2016-01-01

    It is speculated that some weakly active comets may be transitional objects between active and dormant comets. These objects are at a unique stage of the evolution of cometary nuclei, as they are still identifiable as active comets, in contrast to inactive comets that are observationally indistinguishable from low albedo asteroids. In this paper, we present a synthesis of comet and meteor observations of Jupiter-family Comet 209P/LINEAR, one of the most weakly active comets recorded to-date. Images taken by the Xingming 0.35-m telescope and the Gemini Flamingo-2 camera are modeled by a Monte Carlo dust model, which yields a low dust ejection speed (1/10 of that of moderately active comets), dominance of large dust grains, and a low dust production of 0.4kgs-1 at 19 d after the 2014 perihelion passage. We also find a reddish nucleus of 209P/LINEAR that is similar to D-type asteroids and most Trojan asteroids. Meteor observations with the Canadian Meteor Orbit Radar (CMOR), coupled with meteoroid stream modeling, suggest a low dust production of the parent over the past few hundred orbits, although there are hints of a some temporary increase in activity in the 18th century. Dynamical simulations indicate 209P/LINEAR may have resided in a stable near-Earth orbit for ∼104 yr, which is significantly longer than typical JFCs. All these lines of evidence imply that 209P/LINEAR as an aging comet quietly exhausting its remaining near surface volatiles. We also compare 209P/LINEAR to other low activity comets, where evidence for a diversity of the origin of low activity is seen.

  10. Promoting Physical Activity in Low-Active Adolescents via Facebook: A Pilot Randomized Controlled Trial to Test Feasibility.

    PubMed

    Wójcicki, Thomas R; Grigsby-Toussaint, Diana; Hillman, Charles H; Huhman, Marian; McAuley, Edward

    2014-10-30

    The World Wide Web is an effective method for delivering health behavior programs, yet major limitations remain (eg, cost of development, time and resource requirements, limited interactivity). Social media, however, has the potential to deliver highly customizable and socially interactive behavioral interventions with fewer constraints. Thus, the evaluation of social media as a means to influence health behaviors is warranted. The objective of this trial was to examine and demonstrate the feasibility of using an established social networking platform (ie, Facebook) to deliver an 8 week physical activity intervention to a sample of low-active adolescents (N=21; estimated marginal mean age 13.48 years). Participants were randomized to either an experimental (ie, Behavioral) or attentional control (ie, Informational) condition. Both conditions received access to a restricted-access, study-specific Facebook group where the group's administrator made two daily wall posts containing youth-based physical activity information and resources. Primary outcomes included physical activity as assessed by accelerometry and self-report. Interactions and main effects were examined, as well as mean differences in effect sizes. Analyses revealed significant improvements over time on subjectively reported weekly leisure-time physical activity (F1,18=8.426, P=.009, η2 = .319). However, there was no interaction between time and condition (F1,18=0.002, P=.968, η2 = .000). There were no significant time or interaction effects among the objectively measured physical activity variables. Examination of effect sizes revealed moderate-to-large changes in physical activity outcomes. Results provide initial support for the feasibility of delivery of a physical activity intervention to low-active adolescents via social media. Whether by employing behavioral interventions via social media can result in statistically meaningful changes in health-related behaviors and outcomes remains to be

  11. Standards Laboratory environments

    SciTech Connect

    Braudaway, D.W.

    1990-09-01

    Standards Laboratory environments need to be carefully selected to meet the specific mission of each laboratory. The mission of the laboratory depends on the specific work supported, the measurement disciplines required and the level of uncertainty required in the measurements. This document reproduces the contents of the Sandia National Laboratories Primary Standards Laboratory Memorandum Number 3B (PSLM-3B) which was issued on May 16, 1988, under the auspices of the Department of Energy, Albuquerque Operations Office, to guide the laboratories of the Nuclear Weapons Complex in selecting suitable environments. Because of both general interest and specific interest in Standards Laboratory environments this document is being issued in a more available form. The purpose of this document is to provide guidance in selection of laboratory environments suitable for standards maintenance and calibration operations. It is not intended to mandate a specific environment for a specific calibration but to direct selection of the environment and to offer suggestions on how to extend precision in an existing and/or achievable (practical) environment. Although this documents pertains specifically to standards laboratories, it can be applied to any laboratory requiring environmental control.

  12. Aqueous processing in materials science and engineering

    NASA Astrophysics Data System (ADS)

    Mooiman, Michael B.; Sole, Kathryn C.

    1994-06-01

    Reviews of aqueous processing in JOM have traditionally focused on hydrometallurgical process routes. This article, however, addresses the application of aqueous processing in materials engineering and presents some promising developments that employ aqueous-based routes for the manufacture of high-tech components and specialty products. Such applications include producing metallic and ceramic powders; etching; surface modification by electroplating and electroless plating; manufacturing jewelry and intricate components by electroforming; and producing advanced ceramics, composites, and nanophase materials by sol-gel and biomimetic processing.

  13. The Confederate medical laboratories.

    PubMed

    Hasegawa, Guy R; Hambrecht, F Terry

    2003-12-01

    During the Civil War, the scarcity and expense of imported drugs forced the Confederate Army to establish several medical laboratories to manufacture drugs for military use. The laboratories produced medicines from indigenous plants and also made non-plant-based drugs. The Confederate Surgeon General and the Chief Purveyor in Richmond, VA, coordinated activities of most of the laboratories. The laboratories employed talented and resourceful personnel and manufactured a large volume and wide variety of drugs, the most useful of which included ether, chloroform, and opiates. The pharmaceutical quality of the laboratories' output was evidently uneven. Empirical testing in military hospitals helped determine the clinical value of indigenous remedies. The Confederate medical laboratories participated in a coordinated effort to supply the Army with substitutes for drugs whose availability was curtailed or uncertain.

  14. Creep Laboratory manual

    NASA Astrophysics Data System (ADS)

    Osgerby, S.; Loveday, M. S.

    1992-06-01

    A manual for the NPL Creep Laboratory, a collective name given to two testing laboratories, the Uniaxial Creep Laboratory and the Advanced High Temperature Mechanical Testing Laboratory, is presented. The first laboratory is devoted to uniaxial creep testing and houses approximately 50 high sensitivity creep machines including 10 constant stress cam lever machines. The second laboratory houses a low cycle fatigue testing machine of 100 kN capacity driven by a servo-electric actuator, five machines for uniaxial tensile creep testing of engineering ceramics at temperatures up to 1600C, and an electronic creep machine. Details of the operational procedures for carrying out uniaxial creep testing are given. Calibration procedures to be followed in order to comply with the specifications laid down by British standards, and to provide traceability back to the primary standards are described.

  15. Viscosities of aqueous blended amines

    SciTech Connect

    Hsu, C.H.; Li, M.H.

    1997-07-01

    Solutions of alkanolamines are an industrially important class of compounds used in the natural gas, oil refineries, petroleum chemical plants, and synthetic ammonia industries for the removal of acidic components like CO{sub 2} and H{sub 2}S from gas streams. The viscosities of aqueous mixtures of diethanolamine (DEA) + N-methyldiethanolamine (MDEA), DEA + 2-amino-2-methyl-1-propanol (AMP), and monoethanolamine (MEA) + 2-piperidineethanol (2-PE) were measured from 30 C to 80 C. A Redlich-Kister equation for the viscosity deviation was applied to represent the viscosity. On the basis of the available viscosity data for five ternary systems, MEA + MDEA + H{sub 2}O, MEA + AMP + H{sub 2}O, DEA + MDEA + H{sub 2}O, DEA + AMP + H{sub 2}O, and MEA + 2-PE + H{sub 2}O, a generalized set of binary parameters were determined. For the viscosity calculation of the systems tested, the overall average absolute percent deviation is about 1.0% for a total of 499 data points.

  16. Densities of aqueous blended amines

    SciTech Connect

    Hsu, C.H.; Li, M.H.

    1997-05-01

    Solutions of alkanolamines are an industrially important class of compounds used in the natural gas and synthetic ammonia industries and petroleum chemical plants for the removal of CO{sub 2} and H{sub 2}S from gas streams. The densities of aqueous mixtures of diethanolamine (DEA) + N-methyldiethanolamine (MDEA) + water, DEA + 2-amino-2-methyl-1-propanol (AMP) + water, and monoethanolamine (MEA) + 2-piperidineethanol (2-PE) + water were measured from 30 C to 80 C. A Redlich-Kister equation of the excess volume was applied to represent the density. Based on the available density data for five ternary systems: MEA + MDEA + H{sub 2}O, MEA + AMP + H{sub 2}O, DEA + MDEA + H{sub 2}O, DEA + AMP + H{sub 2}O, and MEA + 2-PE + H{sub 2}O, a generalized set of binary parameters were determined. The density calculations show quite satisfactory results. The overall average absolute percent deviation is about 0.04% for a total of 686 data points.

  17. Method for processing aqueous wastes

    SciTech Connect

    Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

    1992-12-31

    This invention is comprised of a method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

  18. Aqueous Alteration of Enstatite Chondrites

    NASA Technical Reports Server (NTRS)

    Zolensky, M. E.; Ziegler, K.; Weisberg, M. K.; Gounelle, M.; Berger, E. L.; Le, L.; Ivanov, A.

    2014-01-01

    The Kaidun meteorite is different from all other meteorites [1], consisting largely of a mixture of “incompatible” types of meteoritic material – carbonaceous and enstatite chondrites, i.e. corre-sponding to the most oxidized and the most reduced samples of meteorite materials, including CI1, CM1-2, CV3, EH3-5, and EL3. In addition to these, minor amounts of ordinary and R chondrites are present. In addition, approximately half of the Kaidun lithologies are new materials not known as separate meteorites. Among these are aqueously altered enstatite chondrites [1], which are of considerable interest because they testify that not all reduced asteroids escaped late-stage oxidation, and hydrolysis, and also because hydrated poorly crystalline Si-Fe phase, which in turn is re-placed by serpentine (Figs 3-5). In the end the only indication of the original presence of metal is the re-sidual carbides. In other enstatite chondrite lithogies (of uncertain type) original silicates and metal have been thoroughly replaced by an assemblage of authi-genic plagioclase laths, calcite boxwork, and occasion-al residual grains of silica, Cr-rich troilite, ilmenite, and rare sulfides including heideite (Fig. 6). Fe and S have been largely leached from the rock (Fig. 4). Again the accessory phases are the first clue to the original character of the rock, which can be verified by O isotopes. It is fortunate that Kaidun displays every step of the alteration process.

  19. Method for processing aqueous wastes

    DOEpatents

    Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

    1993-12-28

    A method is presented for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply. 4 figures.

  20. Method for processing aqueous wastes

    DOEpatents

    Pickett, John B.; Martin, Hollis L.; Langton, Christine A.; Harley, Willie W.

    1993-01-01

    A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

  1. Velocimetry of aqueous foam drainage

    NASA Astrophysics Data System (ADS)

    Kennedy, Matthew J.; Fleming, James W.

    2011-11-01

    We study the flow behavior of a freely draining aqueous foam using microparticle image velocimetry. Video shows liquid traveling uphill along the bubble surfaces, counter-directional to the primary flow. Most theoretical models of foam drainage avoid direct calculation of the flow at the gas-liquid interface. Rather, they treat the effect of surface flow empirically due to lack of experimental and theoretical understanding of the forces which cause flow at the surface. This uphill flow represents a significant component of the overall flow. Understanding the surface-driven flow can improve predictions of water-retention time. In the present work, we use a proprietary fire-suppression foam solution comprising hydrocarbon-based non-fluorinated surfactants in water. At the start of drainage, the mean upward flow speed is 0.2 +/- 0.1 mm/s while the mean downward flow speed is 0.8 +/- 0.1 mm/s. The local bubble size at the location-under-imaging is 0.6 mm with a coefficient of variation of 50%. Ongoing efforts concern the effect of the liquid solution constituents on the uphill flow and the effect of bubble size on drainage time. NRC/NRL Postdoctoral Fellow

  2. Purification of aqueous cellulose ethers

    SciTech Connect

    Bartscherer, K.A.; de Pablo, J.J.; Bonnin, M.C.; Prausnitz, J.M.

    1990-07-01

    Manufacture of cellulose ethers usually involves high amounts of salt by-products. For application of the product, salt must be removed. In this work, we have studied the injection of high-pressure CO{sub 2} into an aqueous polymer-salt solution; we find that upon addition of isopropanol in addition to CO{sub 2}, the solution separates into two phases. One phase is rich in polymer and water, and the other phase contains mostly isopropanol, water and CO{sub 2}. The salt distributes between the two phases, thereby offering interesting possibilities for development of a new purification process for water-soluble polymers. This work presents experimental phase-equilibrium data for hydroxyethyl cellulose and sodium carboxymethyl cellulose with sodium acetate and potassium sulfate, respectively, in the region 40{degree}C and 30 to 80 bar. Based on these data, we suggest a process for the manufacture and purification of water-soluble cellulose ethers. 15 refs., 14 figs., 9 tabs.

  3. Hydrophobic effect at aqueous interfaces

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew

    2005-01-01

    Conceptual basis for hydrophobic effects in bulk water and at aqueous interfaces have similar conceptual basis but often manifests itself differently. Using a wide range of computer simulations as the basis, I will review different forms of hydrophobic effects at a variety of interfaces starting from simple liquid-vapor and water-oil interfaces and progressing to water-membrane interfaces. I will start with discussing how water is organized at different interfaces, stressing both similarities and differences. The main thread is that, as in the bulk liquid, hydrophobic effects have profound influence on conformational equilibria and organization of both small molecules and macromolecules, but the result of this influence is quite different. Specifically, it will be shown that many small, but not necessarily amphiphilic molecules tend to accumulate at the interface and, and this tendency will be explained. Furthermore, I will show that many short peptides that are disordered in water spontaneously fold into well-defined structures in the interfacial environment. Biological implications of this self-organizing effect will be discussed.

  4. Hydrophobic effect at aqueous interfaces

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew

    2005-01-01

    Conceptual basis for hydrophobic effects in bulk water and at aqueous interfaces have similar conceptual basis but often manifests itself differently. Using a wide range of computer simulations as the basis, I will review different forms of hydrophobic effects at a variety of interfaces starting from simple liquid-vapor and water-oil interfaces and progressing to water-membrane interfaces. I will start with discussing how water is organized at different interfaces, stressing both similarities and differences. The main thread is that, as in the bulk liquid, hydrophobic effects have profound influence on conformational equilibria and organization of both small molecules and macromolecules, but the result of this influence is quite different. Specifically, it will be shown that many small, but not necessarily amphiphilic molecules tend to accumulate at the interface and, and this tendency will be explained. Furthermore, I will show that many short peptides that are disordered in water spontaneously fold into well-defined structures in the interfacial environment. Biological implications of this self-organizing effect will be discussed.

  5. Foam fracturing laboratory

    SciTech Connect

    Earl, R.B.; Wendroff, C.L.

    1983-10-01

    A new laboratory has been constructed with test equipment designed to expose foam fracturing fluids to test conditions simulating treatment conditions of shear, time, temperature and pressure during the tests. The goal for designing this laboratory was to simulate treating and downhole conditions as closely as possible and to determine fracturing foam properties under these conditions. This paper describes the design parameters and equipment in this unique laboratory.

  6. Medical Laboratory Assistant. Laboratory Occupations Cluster.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for medical laboratory assistant is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a career ladder, a matrix relating duty/task numbers to job titles, and a task list. Each…

  7. Medical Laboratory Assistant. Laboratory Occupations Cluster.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for medical laboratory assistant is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a career ladder, a matrix relating duty/task numbers to job titles, and a task list. Each…

  8. Laboratory Astrophysics White Paper

    NASA Technical Reports Server (NTRS)

    Brickhouse, Nancy; Federman, Steve; Kwong, Victor; Salama, Farid; Savin, Daniel; Stancil, Phillip; Weingartner, Joe; Ziurys, Lucy

    2006-01-01

    Laboratory astrophysics and complementary theoretical calculations are the foundations of astronomical and planetary research and will remain so for many generations to come. From the level of scientific conception to that of the scientific return, it is our understanding of the underlying processes that allows us to address fundamental questions regarding the origins and evolution of galaxies, stars, planetary systems, and life in the cosmos. In this regard, laboratory astrophysics is much like detector and instrument development at NASA and NSF; these efforts are necessary for the astronomical research being funded by the agencies. The NASA Laboratory Astrophysics Workshop met at the University of Nevada, Las Vegas (UNLV) from 14-16 February, 2006 to identify the current laboratory data needed to support existing and future NASA missions and programs in the Astrophysics Division of the Science Mission Directorate (SMD). Here we refer to both laboratory and theoretical work as laboratory astrophysics unless a distinction is necessary. The format for the Workshop involved invited talks by users of laboratory data, shorter contributed talks and poster presentations by both users and providers that highlighted exciting developments in laboratory astrophysics, and breakout sessions where users and providers discussed each others' needs and limitations. We also note that the members of the Scientific Organizing Committee are users as well as providers of laboratory data. As in previous workshops, the focus was on atomic, molecular, and solid state physics.

  9. Sandia National Laboratories

    NASA Technical Reports Server (NTRS)

    Gilliom, Laura R.

    1992-01-01

    Sandia National Laboratories has identified technology transfer to U.S. industry as a laboratory mission which complements our national security mission and as a key component of the Laboratory's future. A number of technology transfer mechanisms - such as CRADA's, licenses, work-for-others, and consortia - are identified and specific examples are given. Sandia's experience with the Specialty Metals Processing Consortium is highlighted with a focus on the elements which have made it successful. A brief discussion of Sandia's potential interactions with NASA under the Space Exploration Initiative was included as an example of laboratory-to-NASA technology transfer. Viewgraphs are provided.

  10. [Digital echocardiography laboratory].

    PubMed

    Trambaiolo, Paolo; Posteraro, Alfredo; Salustri, Alessandro; Amici, Elisabetta; Piaggio, Maurizio; Decanini, Cesare; Gambelli, Giancarlo

    2004-07-01

    The implementation of a digital echocardiography laboratory exists today using the DICOM (Digital Imaging Communication in Medicine) standard to acquire, store and transfer echocardiographic digital images. The components of a laboratory include: 1) digital echocardiography machines with DICOM output, 2) a switched high-speed local area network, 3) a DICOM server with abundant local storage, and 4) a software to manage image and measurement information. The aim of this article was to describe the critical components of a digital echocardiography laboratory, discuss strategies for implementation, and describe some of the pitfalls that we encountered in our own implementation of the digital third level echocardiography laboratory.

  11. Safety of femtosecond laser-assisted cataract surgery: assessment of aqueous humour and lens capsule.

    PubMed

    Yu, A-Yong; Lin, Cai-Xia; Wang, Qin-Mei; Zheng, Mei-Qing; Qin, Xiao-Yi

    2016-11-01

    To investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on aqueous humour and lens capsule. This prospective randomized comparative study enrolled 19 eyes that underwent FLACS as the trial group and 20 eyes that underwent conventional phacoemulsification as the control group. The femtosecond laser platform (LLS-fs 3D; LensAR, Orlando, FL, USA) was used to generate capsulotomy (laser energy 8 μJ) and lens fragmentation (laser energy 10 μJ). Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humour were identified by mass spectrometry (Ultraflex III TOF/TOF; Bruker Dalton, Bremen, Germany). Electrolyte in the aqueous humour was detected by a chemistry analyzer (Aeroset Clinical Chemistry Analyzer; Abbott Laboratories, Abbott Park, IL, USA). The cutting edge of anterior capsule was saw-tooth-shaped under magnification of 200× and 400× in the trial group, while it was smooth in the control group. Intact cells were found in the boundary area next to the cutting edge of anterior capsule in both groups. β-Crystallin B1, γ-crystallin S and transferrin were detected in the aqueous humour in the trial group. The concentrations of K(+) , Na(+) and Cl(-) in the aqueous humour in the trial group differed significantly from those in the control group (p = 0.02, 0.03 and 0.04, respectively). Femtosecond laser-assisted cataract surgery (FLACS) causes release of transferrin and crystallin from lens to aqueous humour and results in significant changes in the concentrations of K(+) , Na(+) and Cl(-) in aqueous humour. However, these changes due to FLACS have no clinical significance or toxicity. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. Encapsulation and controlled release of hydrophilic pesticide in shell cross-linked nanocapsules containing aqueous core.

    PubMed

    Sun, Chuxiang; Shu, Ke; Wang, Wei; Ye, Zhao; Liu, Ting; Gao, Yuxiang; Zheng, Hua; He, Guanghua; Yin, Yihua

    2014-03-10

    In this study, amphiphilic biocopolymers, synthesized by mixing azidobenzaldehyde (Az) and an aqueous solution of carboxymethyl chitosan (CMCS), which self-assemble into nanocapsules with a aqueous core (ACN) in aqueous media followed by photo-cross-linking to obtain shell cross-linked nanocapsules, were used to develop a controlled release pesticide system. The system was characterized by TEM and DLS. Its encapsulation efficiency was determined. The obtained result showed that it is efficient to encapsulate methomyl reaching encapsulation efficiency as high as 90% in an aqueous medium at pH 4.0, which is mainly attributed to the hydrogen bonding adsorption between methomyl molecules and the inner surface of nanocapsules. Release profiles of methomyl from methomyl-loaded nanocapsules in an aqueous solution at pH 6.0 were shown to be diffusion controlled with a half-release time (t(½)) of 36.3-69.5h from different samples. The shell cross-linking and its degree of cross-linking are assumed to be responsible for this diffusion behavior. The insecticidal activity test in laboratory showed that the control efficacy of methomyl-loaded nanocapsules against the armyworm larvae was significantly superior to the original. The relative control efficacy still maintained 100% over 7 days.

  13. Classification of the crystallization behavior of amorphous active pharmaceutical ingredients in aqueous environments.

    PubMed

    Van Eerdenbrugh, Bernard; Raina, Shweta; Hsieh, Yi-Ling; Augustijns, Patrick; Taylor, Lynne S

    2014-04-01

    To classify the crystallization behavior of amorphous active pharmaceutical ingredients (API) exposed to aqueous environments. A set of approximately 50 chemically and physically diverse active pharmaceutical ingredients (APIs) was selected for this study. Two experimental setups were employed to characterize the crystallization behavior of the amorphous API in an aqueous environment. For the first approach, precipitation, as evidenced by the development of turbidity, was induced using the solvent shift method, by mixing concentrated API solutions in DMSO with an aqueous buffer in a capillary. Subsequently, crystallization was monitored in situ over time using synchrotron radiation (simultaneous SAXS/WAXS beamline 12-ID-B at the Advanced Photon Source, Argonne National Laboratories, Argonne, IL). In the second approach, amorphous films were prepared by melt quenching; after adding buffer, crystallization was monitored with time using polarized light microscopy. In general, the crystallization behavior of a given compound was similar irrespective of the experimental method employed. However, the crystallization behavior among different compounds varied significantly, ranging from immediate and complete crystallization to no observable crystallization over biorelevant time scales. Comparison of the observed behavior with previous studies of crystallization tendency in non-aqueous environments revealed that the crystallization tendency of individual APIs was somewhat similar regardless of the crystallization environment. API properties, rather than the method by which amorphous materials are generated, tend to dictate crystallization behavior in aqueous media.

  14. Removal of phthalate esters from aqueous solutions by chitosan bead.

    PubMed

    Chen, Chih-Yu; Chung, Ying-Chien

    2006-01-01

    Removal of phthalate esters (PAEs) by chitosan bead in aqueous solution was studied. The adsorption isotherms of PAEs by chitosan bead were well described by Freundlich isotherm equations. Results of kinetic experiments indicated that diheptyl phthalate (DHpP) had the highest adsorption capacity (1.52 mg/g) among six PAEs in our research. PAE adsorption efficiency by chitosan bead was examined in both batch and continuous systems, and DHpP attained 74.9% recovery efficiency from chitosan bead by shaking with an equal volume mixture of methanol and water. The recovered chitosan bead was reusable as an adsorbent. The influences of temperature, pH, Ca+2, and NaCl on PAE adsorption were also evaluated to determine performance in different water environments (e.g., groundwater, surface water, and sea water). The results showed that PAE adsorption decreased as temperature increased. From pH experiments it appeared that pH 8.0 was optimal for adsorption. The effect of Ca+2 showed that adsorption efficiency did not change by increasing the concentrations of Ca+2 until 400 mg/L. NaCl coexistence showed an insignificant effect on PAE adsorption. Furthermore, the chitosan bead was also applied to treating the discharge of a plastics plant, and the treatment results resembled those of a laboratory continuous system. This is the first report to use chitosan bead as an adsorbent to adsorb phthalate esters from aqueous solution. These results indicate that the application of chitosan bead is feasible in the aqueous environments of Taiwan.

  15. Advanced oxidation for the treatment of chlorpyrifos in aqueous solution.

    PubMed

    Ismail, M; Khan, Hasan M; Sayed, Murtaza; Cooper, William J

    2013-10-01

    Chlorpyrifos is an organophosphate pesticide and is significant because of its extensive use, persistence in the environment, wide distribution, and its toxicity may lead to lung and central nervous system damage, developmental and autoimmune disorders and vomiting. In the present study, the irradiation of chlorpyrifos in aqueous solution by (60)Co γ-rays was conducted on a laboratory scale and the removal efficiency of chlorpyrifos was investigated. The SPME-GC-ECD method was used for analysis of chlorpyrifos. Aqueous solutions of different concentrations of target compound (200-1000 μg L(-1)) were irradiated through 30-575 Gy. Gamma irradiation showed 100% degradation for a 500 μg L(-1) solution at an absorbed dose of 575 Gy (the dose rate was 300 Gy h(-1)). The radiolysis of chlorpyrifos was pseudo-first order (decay) with respect to dose. The dose constants determined in this study ranged from 8.2×10(-3) to 2.6×10(-2) Gy(-1), and decreased with an increase in the initial concentration of chlorpyrifos, while the radiation chemical yield (G-value) for the loss of chlorpyrifos was found to decrease with increasing absorbed dose. The effect of saturated solutions of N2 and N2O, and radical scavengers tert-butanol, iso-propanol, H2O2, NaNO3 and NaNO2 on the degradation of chlorpyrifos were also studied. The results showed that the oxidative OH was the most important in the degradation of chlorpyrifos, while the reductive radicals, aqueous electron and H, were of less importance for the degradation of chlorpyrifos. The inorganic by-products Cl(-), SO4(2-) and PO4(3-) were quantitatively determined by IC.

  16. VOLATILE ORGANIC ANALYSIS BY DIRECT AQUEOUS INJECTION

    EPA Science Inventory

    Gas chromatographic environmental analysis by direct aqueous injection (DAI) was studied for 24 volatile organic analytes (VOAs). Internal standardization was used to determine the precision of analyzing these compounds by DAI. Aequous samples were directly introduced to a gas ch...

  17. ELECTROCHEMICAL DECHLORINATIONOF 2-CHLOROBIPHENYL IN AQUEOUS SOLUTION

    EPA Science Inventory

    This paper presents electrochemical dechlorination of 2-chlorobiphenyl (2-CI BP) in aqueous environment using palladium modified granular graphite electrodes. 2-CI BP, the PCB congener that requires the highest reduction potential, was effectively dechlorinated in electrochemical...

  18. ELECTROCHEMICAL DECHLORINATIONOF 2-CHLOROBIPHENYL IN AQUEOUS SOLUTION

    EPA Science Inventory

    This paper presents electrochemical dechlorination of 2-chlorobiphenyl (2-CI BP) in aqueous environment using palladium modified granular graphite electrodes. 2-CI BP, the PCB congener that requires the highest reduction potential, was effectively dechlorinated in electrochemical...

  19. Precipitation of neptunium dioxide from aqueous solution

    SciTech Connect

    Roberts, K E

    1999-12-01

    Tens of thousands of metric tons of highly radioactive, nuclear waste have been generated in the US. Currently, there is no treatment or disposal facility for these wastes. Of the radioactive elements in high-level nuclear waste, neptunium (Np) is of particular concern because it has a long half-life and may potentially be very mobile in groundwaters associated with a proposed underground disposal site at Yucca Mountain, Nevada. Aqueous Np concentrations observed in previous, short-term solubility experiments led to calculated potential doses exceeding proposed long-term regulatory limits. However, thermodynamic data for Np at 25 C showed that these observed aqueous Np concentrations were supersaturated with respect to crystalline NpO{sub 2}. It was hypothesized that NpO{sub 2} is the thermodynamically stable solid phase in aqueous solution, but it is slow to form in an aqueous solution of NpO{sub 2}{sup +} on the time scale of previous experiments. The precipitation of NpO{sub 2} would provide significantly lower aqueous Np concentrations leading to calculated doses below proposed regulatory limits. To test this hypothesis, solubility experiments were performed at elevated temperature to accelerate any slow precipitation kinetics. Ionic NpO{sub 2}{sup +} (aq) was introduced into very dilute aqueous solutions of NaCl with initial pH values ranging from 6 to 10. The reaction vessels were placed in an oven and allowed to react at 200 C until steady-state aqueous Np concentrations were observed. In all cases, aqueous Np concentrations decreased significantly from the initial value of 10{sup {minus}4} M. The solids that formed were analyzed by x-ray powder diffraction, x-ray absorption spectroscopy, and scanning electron microscopy. The solids were determined to be high-purity crystals of NpO{sub 2}. This is the first time that crystalline NpO{sub 2} has been observed to precipitate from NpO{sub 2}{sup +}(aq) in near-neutral aqueous solutions. The results obtained

  20. Pilot-scale laboratory waste treatment by supercritical water oxidation.

    PubMed

    Oshima, Yoshito; Hayashi, Rumiko; Yamamoto, Kazuo

    2006-01-01

    Supercritical water oxidation (SCWO) is a reaction in which organics in an aqueous solution can be oxidized by O2 to CO2 and H2O at a very high reaction rate. In 2003, The University of Tokyo constructed a facility for the SCWO process, the capacity of which is approximately 20 kl/year, for the purpose of treating organic laboratory waste. Through the operation of this facility, we have demonstrated that most of the organics in laboratory waste including halogenated organic compounds can be successfully treated without the formation of dioxines, suggesting that SCWO is useful as an alternative technology to the conventional incineration process.

  1. Promoting Physical Activity in Low-Active Adolescents via Facebook: A Pilot Randomized Controlled Trial to Test Feasibility

    PubMed Central

    2014-01-01

    Background The World Wide Web is an effective method for delivering health behavior programs, yet major limitations remain (eg, cost of development, time and resource requirements, limited interactivity). Social media, however, has the potential to deliver highly customizable and socially interactive behavioral interventions with fewer constraints. Thus, the evaluation of social media as a means to influence health behaviors is warranted. Objective The objective of this trial was to examine and demonstrate the feasibility of using an established social networking platform (ie, Facebook) to deliver an 8 week physical activity intervention to a sample of low-active adolescents (N=21; estimated marginal mean age 13.48 years). Methods Participants were randomized to either an experimental (ie, Behavioral) or attentional control (ie, Informational) condition. Both conditions received access to a restricted-access, study-specific Facebook group where the group’s administrator made two daily wall posts containing youth-based physical activity information and resources. Primary outcomes included physical activity as assessed by accelerometry and self-report. Interactions and main effects were examined, as well as mean differences in effect sizes. Results Analyses revealed significant improvements over time on subjectively reported weekly leisure-time physical activity (F 1,18=8.426, P=.009, η2 = .319). However, there was no interaction between time and condition (F 1,18=0.002, P=.968, η2 = .000). There were no significant time or interaction effects among the objectively measured physical activity variables. Examination of effect sizes revealed moderate-to-large changes in physical activity outcomes. Conclusions Results provide initial support for the feasibility of delivery of a physical activity intervention to low-active adolescents via social media. Whether by employing behavioral interventions via social media can result in statistically meaningful changes in

  2. RECOVERY OF TETRAVALENT CATIONS FROM AQUEOUS SOLUTIONS

    DOEpatents

    Moore, R.L.

    1958-05-01

    The recovery of plutonium, zirconium, and tetravalent cerium values from aqueous solutions is described. It consists of adding an alkyl phosphate to a nnineral acid aqueous solution containing the metal to be recovered, whereby a precipitate forms with the tetravalent values, and separating the precipitate from the solution. All alkyl phosphates, if water-soluble, are suitable for the process; however, monobutyl phosphate has been found best.

  3. EXTRACTION OF URANYL NITRATE FROM AQUEOUS SOLUTIONS

    DOEpatents

    Furman, N.H.; Mundy, R.J.

    1957-12-10

    An improvement in the process is described for extracting aqueous uranyl nitrate solutions with an organic solvent such as ether. It has been found that the organic phase will extract a larger quantity of uranyl nitrate if the aqueous phase contains in addition to the uranyl nitrate, a quantity of some other soluble nitrate to act as a salting out agent. Mentioned as suitable are the nitrates of lithium, calcium, zinc, bivalent copper, and trivalent iron.

  4. Colorimetric estimation of phospholipids in aqueous dispersions.

    PubMed

    Hallen, R M

    1980-05-01

    A method for the estimation of phospholipids in aqueous dispersions is described. The method is based on the formation of a lipid-molybdenum blue complex, which is extracted into chloroform from the aqueous phase. Phosphate ions, detergents, proteins, neutral lipids and various other ions do not interfere in the lipid estimation. The method is sensitive down to a lipid concentration of 0.1 mumol/ml, with an accuracy better than +/- 3%.

  5. Reductive dehalogenation of bromoform in aqueous solution.

    PubMed

    Betterton, E A; Arnold, R G; Kuhler, R J; Santo, G A

    1995-06-01

    The hybrid semiconducter-macrocycle catalyst TiO2-cobalt phthalocyanine promotes the solar photolysis of aqueous bromoform under anaerobic conditions. The major decomposition products are dibromoethane and HBr. Bromomethane and methane were produced only after prolonged photolysis (30 hr). Acetone, derived from added 2-propanol, was the only observed oxidation product. Preliminary experiments showed that electrolytic reduction of aqueous carbon tetrachloride at a vitamin B12-modified silver electrode produced the expected lower homologues but with surprisingly high yields of methane.

  6. Laser-induced breakdown system for colloid characterization in dilute aqueous suspensions

    SciTech Connect

    Brachman, A; Mihardja, S; Palmer, C A; Wruck, D

    1999-08-11

    Detection and sizing of colloids by acoustic detection of laser-induced breakdown and elemental analysis of colloids by laser-induced breakdown spectroscopy are investigated in dilute aqueous suspensions. Development and testing of the methods are performed with standard polystyrene suspensions and prepared suspensions of defined composition and particle size. Application of the methods to analysis of field and laboratory samples is discussed. Am atomic emission lines are observed by laser-induced breakdown spectroscopy of an Am hydroxycarbonate suspension.

  7. Argonne National Laboratory`s photo-oxidation organic mixed waste treatment system - installation and startup testing

    SciTech Connect

    Shearer, T.L.; Nelson, R.A.; Torres, T.; Conner, C.; Wygmans, D.

    1997-09-01

    This paper describes the installation and startup testing of the Argonne National Laboratory (ANL-E) Photo-Oxidation Organic Mixed Waste Treatment System. This system will treat organic mixed (i.e., radioactive and hazardous) waste by oxidizing the organics to carbon dioxide and inorganic salts in an aqueous media. The residue will be treated in the existing radwaste evaporators. The system is installed in the Waste Management Facility at the ANL-E site in Argonne, Illinois. 1 fig.

  8. DOE workshop: Sedimentary systems, aqueous and organic geochemistry

    SciTech Connect

    Not Available

    1993-07-01

    A DOE workshop on sedimentary systems, aqueous and organic geochemistry was held July 15-16, 1993 at Lawrence Berkeley Laboratory. Papers were organized into several sections: Fundamental Properties, containing papers on the thermodynamics of brines, minerals and aqueous electrolyte solutions; Geochemical Transport, covering 3-D imaging of drill core samples, hydrothermal geochemistry, chemical interactions in hydrocarbon reservoirs, fluid flow model application, among others; Rock-Water Interactions, with presentations on stable isotope systematics of fluid/rock interaction, fluid flow and petotectonic evolution, grain boundary transport, sulfur incorporation, tracers in geologic reservoirs, geothermal controls on oil-reservoir evolution, and mineral hydrolysis kinetics; Organic Geochemistry covered new methods for constraining time of hydrocarbon migration, kinetic models of petroleum formation, mudstones in burial diagenesis, compound-specific carbon isotope analysis of petroleums, stability of natural gas, sulfur in sedimentary organic matter, organic geochemistry of deep ocean sediments, direct speciation of metal by optical spectroscopies; and lastly, Sedimentary Systems, covering sequence stratigraphy, seismic reflectors and diagenetic changes in carbonates, geochemistry and origin of regional dolomites, and evidence of large comet or asteroid impacts at extinction boundaries.

  9. Efficient salt-aided aqueous extraction of bitter almond oil.

    PubMed

    Liu, Lei; Yu, Xiuzhu; Zhao, Zhong; Xu, Lirong; Zhang, Rui

    2017-08-01

    Salt-aided aqueous extraction (SAAE) is an inexpensive and environmentally friendly method of oil extraction that is influenced by many factors. In the present study, we investigated the effect of SAAE on bitter almond oil yield. This study used sodium bicarbonate solution as extraction solvent and the optimal extraction parameters predicted by Box-Behnken design (i.e., concentration of sodium bicarbonate, 0.4 mol L(-1) ; solvent-to-sample ratio, 5:1; extraction temperature, 84 °C; extraction time, 60 min), for oil recovery of 90.9%. The physiochemical characteristics of the extracted oil suggest that the quality was similar to that of the aqueous enzymatic extracted oil. Moreover, the content of hydrocyanic acid (HCN) in bitter almond oil was found to be less than 5 mg kg(-1) , which was lower compared to that obtained by other reported methods. Results of microanalysis indicated that SAAE led to significant improvement in oil yield by allowing the release of oil and decreasing the emulsion fraction. Therefore, extraction of bitter almond oil by SAAE is feasible. These results demonstrate that extraction of bitter almond oil by SAAE based on the salt effect is feasible on a laboratory scale. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Pulse radiolysis of aqueous solutions of sodium tetraphenylborate

    NASA Astrophysics Data System (ADS)

    Crawford, Charles L.; Gholami, Mohammad R.; Bhave, Ravindra N.; Hanrahan, Robert J.

    1994-09-01

    In previous work on the 60Co γ-radiolysis of aqueous tetraphenylborate (TPB -) solutions carried out in this laboratory, it was found that several organic products, including benzene, phenol and biphenyl, are produced with substantial yield. However, the reaction mechanism was not established. In the present study, reactions initiated by OḢ radicals, N 3 radicals and e -aq in aqueous TPB - solutions were studied by pulse radiolysis using a 600 keV Febetron electron accelerator. The lack of reactivity between TPB - and e -aq was demonstrated by directly monitoring the transient optical absorbance of e -aq. Concerning the reaction with O Ḣ, two schemes were considered: (1) electron transfer from B(C 6H 5) -4 to O Ḣ; or (2) O Ḣ addition to B(C 6H 5) -4. Comparison of observed transient absorption spectra with expectations based on two different schemes suggests that O Ḣ addition is the dominant reaction pathway under conditions of N 2O saturation, with an experimentally determined second-order rate constant of 6.2×10 9M -1s -1. A mechanism based on an initial first-order self-decomposition of the O Ḣ adduct, (C 6H 5) 3BC 6H 5OH -· with a measured rate constant of 4×10 4s -1 is proposed. Kinetic modeling on the proposed mechanistic scheme gives good agreement with our experimental results.

  11. Photochemistry of Tetrabromobisphenol A in Frozen and Liquid Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Reich, J.; Grannas, A. M.; Dolak, E.

    2012-12-01

    Brominated flame retardants are an emerging environmental contaminant and are now globally distributed in the environment, including the Polar Regions. Because bioaccumulation presents serious concerns for human and wildlife health within the Arctic, it is important to assess the potential fate of these contaminants. Despite some established knowledge regarding photochemical processes in reactive frozen media, little published literature exists regarding the chemical transformations and fate of brominated flame retardants in the Arctic. Here, we consider the photochemical transformation of tetrabromobisphenol A (TBBPA). We have conducted field-based experiments in Barrow, Alaska to investigate the potential photochemical degradation of TBBPA in snow/ice samples and found that TBBPA was efficiently photodegraded in frozen aqueous samples under natural Barrow sunlight. The main pathway of degradation was direct photolysis and the addition of photosensitizers had no significant impact on TBBPA photodegradation. In aqueous solution the solubility and light absorption properties of TBBPA are pH dependent, indicating that the photodegradation of TBBPA in the environment will be highly pH dependent. Reactions than are pH dependent may be affected by the nature of the liquid-like layers in snow/ice as well as the presence of other solutes that may indirectly affect the local pH. Here we will discuss our field and laboratory-based results investigating the role that snow/ice composition may play on TBBPA photochemical reactivity.

  12. Radiolytic degradation of malathion and lindane in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Mohamed, K. A.; Basfar, A. A.; Al-Kahtani, H. A.; Al-Hamad, K. S.

    2009-11-01

    Degradation of malathion and lindane pesticides present in an aqueous solution was investigated on a laboratory scale upon gamma-irradiation from a 60Co source. The effects of pesticide group, presence of various additives and absorbed dose on efficiency of pesticide degradation were investigated. Gamma-irradiation was carried out in distilled water solutions (malathion and lindane) and in combination with humic solution (HS), nitrous oxide (N 2O) and HS/N 2O (lindane) over the range 0.1-2 kGy (malathion) and 5-30 kGy (lindane). Malathion was easily degraded at low absorbed doses compared to lindane in distilled water solutions. Absorbed doses required to remove 50% and 90% of initial malathion and lindane concentrations in distilled water solutions were 0.53 and 1.77 kGy (malathion) and 17.97 and 28.79 kGy (lindane), respectively. The presence of HS, N 2O and HS/N 2O additives in aqueous solutions, significantly improved the effectiveness of radiolytic degradation of lindane. Chemical analysis of the pesticides and the by-products resulted from the radiolytic degradation were made using a gas chromatography associated with mass spectrometry (GC-MS). Additionally, the final degradation products of irradiation as detected by ion chromatography (IC) were acetic acid and traces of some anions (phosphate and chloride).

  13. Integrated management of radioactive strontium contamination in aqueous stream systems.

    PubMed

    Chaalal, O; Islam, M R

    2001-01-01

    A combination of biomass treatment, fluidized bed/membrane reactor, and a minimum-suspension fluidized bed reactor is proposed to remove strontium cations from aqueous solutions, such as those generated by nuclear reactors. After conducting a series of screening tests, three adsorbents were selected for their suitability and high adsorptive capacity. The proposed combination uses Chlorella vulgaris in a packed column, followed by the fluidized bed/membrane reactor with bentonite powder in suspension. The membrane is primarily used to retain bentonite powder in the reactor. However, the same can be designed to remove additional amount of contaminant from the aqueous stream. The final separation is carried out in a fluidized bed containing resins that are suspended with minimal airflow. In laboratory scale, a flow rate of 600 ml/h was achieved for 30 min during which period the inlet concentration of 100 mg/l was reduced to 2.5 mg/l at the outlet. Bio-encapsulation with thermophilic bacteria and subsequent separation is proposed at this point in order to reduce the concentration to an even lower level. The proposed separation scheme offers an acceptable solution to removing strontium while minimizing the generation of secondary waste.

  14. Biodegradation of N-Nitrosodimethylamine in aqueous and soil systems

    SciTech Connect

    Kaplan, D.L.; Kaplan, A.M.

    1985-10-01

    N-Nitrosodimethylamine (NDMA) was mineralized by microorganisms in aqueous and soil systems. Initial rates of mineralization (micrograms per milliliter per day) were calculated for a wide range of initial concentrations of NDMA (micrograms per milliliter to picograms per milliliter). Log-log plots of the data were fitted with both linear and nonlinear least-squares analyses; however, linear models provided better fits for the kinetic data in all cases. The slopes of the linear fits were not significantly different than 1.0 (P < 0.05); thus, first-order reaction kinetics were in effect over the range of concentrations tested, and saturation kinetics were not achieved. Rate constants (day/sup -1/) and total percent mineralized increased with decreasing initial concentrations of NDMA. Rates of mineralization were reduced in aqueous systems when supplemental carbon was available, whereas in soils, percentages of organic matter and supplemental carbon had little effect on rates of mineralization. Implications of these results for predictions of rates and threshold limits of mineralization activity in natural systems are discussed. A laboratory scale simulated trickling filter containing an activated charcoal bed provided a suitable environment for mineralization of NDMA at concentrations of 50 and 100 ..mu..g/ml on a continuous basis. NDMA was not toxic to natural populations of microorganisms at concentrations up to 10 mg/ml. Using high-pressure liquid chromatography coupled with radioactivity detection. The authors identified formaldehyde and methylamine as intermediates produced during the biodegradation of NDMA.

  15. Biodegradation of N-Nitrosodimethylamine in Aqueous and Soil Systems

    PubMed Central

    Kaplan, David L.; Kaplan, Arthur M.

    1985-01-01

    N-Nitrosodimethylamine (NDMA) was mineralized by microorganisms in aqueous and soil systems. Initial rates of mineralization (micrograms per milliliter per day) were calculated for a wide range of initial concentrations of NDMA (micrograms per milliliter to picograms per milliliter). Log-log plots of the data were fitted with both linear and nonlinear least-squares analyses; however, linear models provided better fits for the kinetic data in all cases. The slopes of the linear fits were not significantly different than 1.0 (P < 0.05); thus, first-order reaction kinetics were in effect over the range of concentrations tested, and saturation kinetics were not achieved. Rate constants (day−1) and total percent mineralized increased with decreasing initial concentrations of NDMA. Rates of mineralization were reduced in aqueous systems when supplemental carbon was available, whereas in soils, percentages of organic matter and supplemental carbon had little effect on rates of mineralization. Implications of these results for predictions of rates and threshold limits of mineralization activity in natural systems are discussed. A laboratory scale simulated trickling filter containing an activated charcoal bed provided a suitable environment for mineralization of NDMA at concentrations of 50 and 100 μg/ml on a continuous basis. NDMA was not toxic to natural populations of microorganisms at concentrations up to 10 mg/ml. Using high-pressure liquid chromatography coupled with radioactivity detection, we identified formaldehyde and methylamine as intermediates produced during the biodegradation of NDMA. PMID:16346905

  16. Aqueous Solvation at Biomimetic Interfaces

    NASA Astrophysics Data System (ADS)

    Benderskii, Alexander V.; Eisenthal, Kenneth B.

    2002-03-01

    The process of solvation has been investigated at model aqueous interfaces designed to mimic surfaces of biomembranes. Second Harmonic Generation spectroscopy of a solvatochromic dye coumarin 314 is employed as the surface-selective probe technique. Monolayers of lipid amphiphiles at the air/water interface are used as model systems with neutral or charged hydrophilic headgroups of the surfactants chosen to represent common functional groups present at biological aqueous interfaces such as cell membranes. The red shift of the probe transition was measured using the steady-state frequency-resolved SHG spectroscopy to characterize the equilibrium solvation energies, i.e. the polarity at the lipid interfaces. Femtosecond time-resolved SHG measurements revealed two diffusive components of the solvation dynamics, associated with rearrangement of the water hydrogen bond network. Dynamics at the air/water interface, t1=250 fs and t2=2.0 ps, are similar to the timescales reported for bulk water t1 200 fs and t2 1.2 ps. The dynamical properties of water near the surfactant interfaces are significantly modified by the electrostatic and H-bonding interactions with the hydrophilic lipid headgroups. Neutral carboxyl headgroups (200 Å2/molecule) result in slowing of t1 to 400 fs and suppression of the slower t2 component. Different anionic lipids, carboxylate and sulfate, produce similar effects, slowing the t1 and t2 components without significantly affecting their relative amplitudes. Studies as a function of the sulfate surfactant concentration revealed that at low to intermediate surface coverage (500 to 250 Å2/molecule), the t1 component is unaffected, t1=250 fs, while the t2 component is lengthened first to 4.4 ps and then to 5.2 ps. At the highest surface coverage studied, 100 Å2/molecule, t1 changes to 600 fs, while t2 shows "saturation" at 5.4 ps. Different behavior of the two dynamical timescales t1 and t2 as a function of the surface charge density and chemical

  17. AQUEOUS HOMOGENEOUS REACTORTECHNICAL PANEL REPORT

    SciTech Connect

    Diamond, D.J.; Bajorek, S.; Bakel, A.; Flanagan, G.; Mubayi, V.; Skarda, R.; Staudenmeier, J.; Taiwo, T.; Tonoike, K.; Tripp, C.; Wei, T.; Yarsky, P.

    2010-12-03

    Considerable interest has been expressed for developing a stable U.S. production capacity for medical isotopes and particularly for molybdenum- 99 (99Mo). This is motivated by recent re-ductions in production and supply worldwide. Consistent with U.S. nonproliferation objectives, any new production capability should not use highly enriched uranium fuel or targets. Conse-quently, Aqueous Homogeneous Reactors (AHRs) are under consideration for potential 99Mo production using low-enriched uranium. Although the Nuclear Regulatory Commission (NRC) has guidance to facilitate the licensing process for non-power reactors, that guidance is focused on reactors with fixed, solid fuel and hence, not applicable to an AHR. A panel was convened to study the technical issues associated with normal operation and potential transients and accidents of an AHR that might be designed for isotope production. The panel has produced the requisite AHR licensing guidance for three chapters that exist now for non-power reactor licensing: Reac-tor Description, Reactor Coolant Systems, and Accident Analysis. The guidance is in two parts for each chapter: 1) standard format and content a licensee would use and 2) the standard review plan the NRC staff would use. This guidance takes into account the unique features of an AHR such as the fuel being in solution; the fission product barriers being the vessel and attached systems; the production and release of radiolytic and fission product gases and their impact on operations and their control by a gas management system; and the movement of fuel into and out of the reactor vessel.

  18. Aqueous geochemistry on early Mars.

    PubMed

    Schaefer, M W

    1993-10-01

    A geochemical cycle model is presented for the interaction between the atmosphere, hydrosphere, and regolith of Mars. It was developed to study how this interaction might have produced the present Martian environment from a primitive Martian environment much like that of the primitive Earth. The model is a simple system, consisting of an unweathered starting material (calcium-bearing and magnesium-bearing silicates), a CO2 atmosphere, an ocean of water in contact with both the atmosphere and the unweathering starting material, and both calcite and dolomite precipitates. Several interesting points arise from this model. A 1-bar CO2 atmosphere can be removed by carbonate precipitation alone in about half a billion years. This is roughly fifty times longer than earlier estimates, which were not based on time-varying models (Fanale et al., 1982; Carr, 1986; Pollack et al., 1987). One of the chief problems in Martian geology has been how to explain the large number and wide variety of surface features that were apparently formed by aqueous erosion. This longer atmospheric lifetime may be enough to explain the large number of channels seen on older Martian terrain. If the atmosphere started out with more than 1 bar of CO2, it would take correspondingly longer to remove it. If there should be no other means to remove CO2 from the atmosphere, this long time constant would indicate that the atmosphere could never have contained more than a few bars of CO2, or else there would still be remnants present today. The increase in alkalinity of the ocean as the atmosphere disappears, even without the effects of reduction in the amount of water available, indicates that evaporite deposits may have formed on Mars. If these deposits are still present, they may even yet contain some liquid water.

  19. Fenton chemistry at aqueous interfaces

    PubMed Central

    Enami, Shinichi; Sakamoto, Yosuke; Colussi, Agustín J.

    2014-01-01

    In a fundamental process throughout nature, reduced iron unleashes the oxidative power of hydrogen peroxide into reactive intermediates. However, notwithstanding much work, the mechanism by which Fe2+ catalyzes H2O2 oxidations and the identity of the participating intermediates remain controversial. Here we report the prompt formation of O=FeIVCl3− and chloride-bridged di-iron O=FeIV·Cl·FeIICl4− and O=FeIV·Cl·FeIIICl5− ferryl species, in addition to FeIIICl4−, on the surface of aqueous FeCl2 microjets exposed to gaseous H2O2 or O3 beams for <50 μs. The unambiguous identification of such species in situ via online electrospray mass spectrometry let us investigate their individual dependences on Fe2+, H2O2, O3, and H+ concentrations, and their responses to tert-butanol (an ·OH scavenger) and DMSO (an O-atom acceptor) cosolutes. We found that (i) mass spectra are not affected by excess tert-butanol, i.e., the detected species are primary products whose formation does not involve ·OH radicals, and (ii) the di-iron ferryls, but not O=FeIVCl3−, can be fully quenched by DMSO under present conditions. We infer that interfacial Fe(H2O)n2+ ions react with H2O2 and O3 >103 times faster than Fe(H2O)62+ in bulk water via a process that favors inner-sphere two-electron O-atom over outer-sphere one-electron transfers. The higher reactivity of di-iron ferryls vs. O=FeIVCl3− as O-atom donors implicates the electronic coupling of mixed-valence iron centers in the weakening of the FeIV–O bond in poly-iron ferryl species. PMID:24379389

  20. ASRM process development in aqueous cleaning

    NASA Astrophysics Data System (ADS)

    Swisher, Bill

    1992-12-01

    Viewgraphs are included on process development in aqueous cleaning which is taking place at the Aerojet Advanced Solid Rocket Motor (ASRM) Division under a NASA Marshall Space and Flight Center contract for design, development, test, and evaluation of the ASRM including new production facilities. The ASRM will utilize aqueous cleaning in several manufacturing process steps to clean case segments, nozzle metal components, and igniter closures. ASRM manufacturing process development is underway, including agent selection, agent characterization, subscale process optimization, bonding verification, and scale-up validation. Process parameters are currently being tested for optimization utilizing a Taguci Matrix, including agent concentration, cleaning solution temperature, agitation and immersion time, rinse water amount and temperature, and use/non-use of drying air. Based on results of process development testing to date, several observations are offered: aqueous cleaning appears effective for steels and SermeTel-coated metals in ASRM processing; aqueous cleaning agents may stain and/or attack bare aluminum metals to various extents; aqueous cleaning appears unsuitable for thermal sprayed aluminum-coated steel; aqueous cleaning appears to adequately remove a wide range of contaminants from flat metal surfaces, but supplementary assistance may be needed to remove clumps of tenacious contaminants embedded in holes, etc.; and hot rinse water appears to be beneficial to aid in drying of bare steel and retarding oxidation rate.

  1. ASRM process development in aqueous cleaning

    NASA Technical Reports Server (NTRS)

    Swisher, Bill

    1992-01-01

    Viewgraphs are included on process development in aqueous cleaning which is taking place at the Aerojet Advanced Solid Rocket Motor (ASRM) Division under a NASA Marshall Space and Flight Center contract for design, development, test, and evaluation of the ASRM including new production facilities. The ASRM will utilize aqueous cleaning in several manufacturing process steps to clean case segments, nozzle metal components, and igniter closures. ASRM manufacturing process development is underway, including agent selection, agent characterization, subscale process optimization, bonding verification, and scale-up validation. Process parameters are currently being tested for optimization utilizing a Taguci Matrix, including agent concentration, cleaning solution temperature, agitation and immersion time, rinse water amount and temperature, and use/non-use of drying air. Based on results of process development testing to date, several observations are offered: aqueous cleaning appears effective for steels and SermeTel-coated metals in ASRM processing; aqueous cleaning agents may stain and/or attack bare aluminum metals to various extents; aqueous cleaning appears unsuitable for thermal sprayed aluminum-coated steel; aqueous cleaning appears to adequately remove a wide range of contaminants from flat metal surfaces, but supplementary assistance may be needed to remove clumps of tenacious contaminants embedded in holes, etc.; and hot rinse water appears to be beneficial to aid in drying of bare steel and retarding oxidation rate.

  2. Quality in Teaching Laboratories.

    ERIC Educational Resources Information Center

    Stubington, John F.

    1995-01-01

    Describes a Japanese process-oriented approach called KAIZEN for improving the quality of existing teaching laboratories. It provides relevant quality measurements and indicates how quality can be improved. Use of process criteria sidesteps the difficulty of defining quality for laboratory experiments and allows separation of student assessment…

  3. Medical Laboratory Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of medical laboratory technician, lists technical competencies and competency builders for 18 units pertinent to the health technologies cluster in general and 8 units specific to the occupation of medical laboratory technician. The following…

  4. Laboratory for Oceans

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A review is made of the activities of the Laboratory for Oceans. The staff and the research activities are nearly evenly divided between engineering and scientific endeavors. The Laboratory contributes engineering design skills to aircraft and ground based experiments in terrestrial and atmospheric sciences in cooperation with scientists from labs in Earth sciences.

  5. Biotechnology Laboratory Methods.

    ERIC Educational Resources Information Center

    Davis, Robert H.; Kompala, Dhinakar S.

    1989-01-01

    Describes a course entitled "Biotechnology Laboratory" which introduces a variety of laboratory methods associated with biotechnology. Describes the history, content, and seven experiments of the course. The seven experiments are selected from microbiology and molecular biology, kinetics and fermentation, and downstream…

  6. Primary Standards Laboratory report

    SciTech Connect

    Not Available

    1990-12-01

    Sandia National Laboratories operates the Primary Standards Laboratory (PSL) for the Department of Energy, Albuquerque Operations Office (DOE/AL). This report summarizes metrology activities that received emphasis in the first half of 1990 and provides information pertinent to the operation of the DOE/AL system-wide Standards and Calibration Program.

  7. The Language Laboratory.

    ERIC Educational Resources Information Center

    Hocking, Elton

    This condensed article on the language laboratory describes educational and financial possibilities and limitations, often citing the foreign language program at Purdue University as an example. The author discusses: (1) costs and amortization, (2) preventive maintenance, (3) laboratory design, (4) the multichannel recorder, and (5) visuals. Other…

  8. Practical Laboratory Planning.

    ERIC Educational Resources Information Center

    Ferguson, W. R.

    This book is intended as a guide for people who are planning chemistry and physics research laboratories. It deals with the importance of effective communication between client and architect, the value of preliminary planning, and the role of the project officer. It also discusses the size and layout of individual laboratories, the design of…

  9. On National Laboratory Organization.

    ERIC Educational Resources Information Center

    Miller, James O.; And Others

    This paper discusses the problems and issues involved in the organizational structure of the National Laboratory on Early Childhood Education. The National Laboratory, which consisted of a coordination center and six university based research and development centers, was organized for the purpose of planning, sponsoring and conducting research and…

  10. NVLAP calibration laboratory program

    SciTech Connect

    Cigler, J.L.

    1993-12-31

    This paper presents an overview of the progress up to April 1993 in the development of the Calibration Laboratories Accreditation Program within the framework of the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST).

  11. Practical Laboratory Planning.

    ERIC Educational Resources Information Center

    Ferguson, W. R.

    This book is intended as a guide for people who are planning chemistry and physics research laboratories. It deals with the importance of effective communication between client and architect, the value of preliminary planning, and the role of the project officer. It also discusses the size and layout of individual laboratories, the design of…

  12. The Regional Educational Laboratories.

    ERIC Educational Resources Information Center

    Office of Educational Research and Improvement (ED), Washington, DC. Office of Reform Assistance and Dissemination.

    The Regional Educational Laboratory Program is the U.S. Department of Education's largest research and development investment designed to help educators, policymakers, and communities improve schools and help all students attain their potential. The network of 10 regional laboratories works to ensure that those involved in education improvement at…

  13. Technology Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Brame, Ray; And Others

    This guide contains 43 modules of laboratory activities for technology education courses. Each module includes an instructor's resource sheet and the student laboratory activity. Instructor's resource sheets include some or all of the following elements: module number, course title, activity topic, estimated time, essential elements, objectives,…

  14. Quality in Teaching Laboratories.

    ERIC Educational Resources Information Center

    Stubington, John F.

    1995-01-01

    Describes a Japanese process-oriented approach called KAIZEN for improving the quality of existing teaching laboratories. It provides relevant quality measurements and indicates how quality can be improved. Use of process criteria sidesteps the difficulty of defining quality for laboratory experiments and allows separation of student assessment…

  15. Dental Laboratory Technology.

    ERIC Educational Resources Information Center

    Department of the Air Force, Washington, DC.

    The Air Force dental laboratory technology manual is designed as a basic training text as well as a reference source for dental laboratory technicians, a specialty occupation concerned with the design, fabrication, and repair of dental prostheses. Numerous instructive diagrams and photographs are included throughout the manual. The comprehensive…

  16. Dental Laboratory Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of dental laboratory technician, lists technical competencies and competency builders for 13 units pertinent to the health technologies cluster in general and 8 units to the occupation of dental laboratory technician. The following skill areas…

  17. Biotechnology Laboratory Methods.

    ERIC Educational Resources Information Center

    Davis, Robert H.; Kompala, Dhinakar S.

    1989-01-01

    Describes a course entitled "Biotechnology Laboratory" which introduces a variety of laboratory methods associated with biotechnology. Describes the history, content, and seven experiments of the course. The seven experiments are selected from microbiology and molecular biology, kinetics and fermentation, and downstream…

  18. Dental Laboratory Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of dental laboratory technician, lists technical competencies and competency builders for 13 units pertinent to the health technologies cluster in general and 8 units to the occupation of dental laboratory technician. The following skill areas…

  19. Technology Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Brame, Ray; And Others

    This guide contains 43 modules of laboratory activities for technology education courses. Each module includes an instructor's resource sheet and the student laboratory activity. Instructor's resource sheets include some or all of the following elements: module number, course title, activity topic, estimated time, essential elements, objectives,…

  20. Dental Laboratory Technology.

    ERIC Educational Resources Information Center

    Department of the Air Force, Washington, DC.

    The Air Force dental laboratory technology manual is designed as a basic training text as well as a reference source for dental laboratory technicians, a specialty occupation concerned with the design, fabrication, and repair of dental prostheses. Numerous instructive diagrams and photographs are included throughout the manual. The comprehensive…

  1. Medical Laboratory Technician.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center on Education and Training for Employment.

    This document, which is designed for use in developing a tech prep competency profile for the occupation of medical laboratory technician, lists technical competencies and competency builders for 18 units pertinent to the health technologies cluster in general and 8 units specific to the occupation of medical laboratory technician. The following…

  2. The Virtual Robotics Laboratory

    SciTech Connect

    Kress, R.L.; Love, L.J.

    1999-09-01

    The growth of the Internet has provided a unique opportunity to expand research collaborations between industry, universities, and the national laboratories. The Virtual Robotics Laboratory (VRL) is an innovative program at Oak Ridge National Laboratory (ORNL) that is focusing on the issues related to collaborative research through controlled access of laboratory equipment using the World Wide Web. The VRL will provide different levels of access to selected ORNL laboratory secondary education programs. In the past, the ORNL Robotics and Process Systems Division has developed state-of-the-art robotic systems for the Army, NASA, Department of Energy, Department of Defense, as well as many other clients. After proof of concept, many of these systems sit dormant in the laboratories. This is not out of completion of all possible research topics. but from completion of contracts and generation of new programs. In the past, a number of visiting professors have used this equipment for their own research. However, this requires that the professor, and possibly his/her students, spend extended periods at the laboratory facility. In addition, only a very exclusive group of faculty can gain access to the laboratory and hardware. The VRL is a tool that enables extended collaborative efforts without regard to geographic limitations.

  3. The Virtual Robotics Laboratory

    SciTech Connect

    Kress, R.L.; Love, L.J.

    1997-03-01

    The growth of the Internet has provided a unique opportunity to expand research collaborations between industry, universities, and the national laboratories. The Virtual Robotics Laboratory (VRL) is an innovative program at Oak Ridge National Laboratory (ORNL) that is focusing on the issues related to collaborative research through controlled access of laboratory equipment using the World Wide Web. The VRL will provide different levels of access to selected ORNL laboratory equipment to outside universities, industrial researchers, and elementary and secondary education programs. In the past, the ORNL Robotics and Process Systems Division (RPSD) has developed state-of-the-art robotic systems for the Army, NASA, Department of Energy, Department of Defense, as well as many other clients. After proof of concept, many of these systems sit dormant in the laboratories. This is not out of completion of all possible research topics, but from completion of contracts and generation of new programs. In the past, a number of visiting professors have used this equipment for their own research. However, this requires that the professor, and possibly his students, spend extended periods at the laboratory facility. In addition, only a very exclusive group of faculty can gain access to the laboratory and hardware. The VRL is a tool that enables extended collaborative efforts without regard to geographic limitations.

  4. Analysis of Direct Samples of Early Solar System Aqueous Fluids

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael E.; Bodnar, R J.; Fedele, L.; Yurimoto,H.; Itoh, S.; Fries, M.; Steele, A.

    2012-01-01

    Over the past three decades we have become increasingly aware of the fundamental importance of water, and aqueous alteration, on primitive solar-system bodies. Some carbonaceous and ordinary chondrites have been altered by interactions with liquid water within the first 10 million years after formation of their parent asteroids. Millimeter to centimeter-sized aggregates of purple halite containing aqueous fluid inclusions were found in the matrix of two freshly-fallen brecciated H chondrite falls, Monahans (1998, hereafter simply "Monahans") (H5) and Zag (H3-6) (Zolensky et al., 1999; Whitby et al., 2000; Bogard et al., 2001) In order to understand origin and evolution of the aqueous fluids inside these inclusions we much measure the actual fluid composition, and also learn the O and H isotopic composition of the water. It has taken a decade for laboratory analytical techniques to catch up to these particular nanomole-sized aqueous samples. We have recently been successful in (1) measuring the isotopic composition of H and O in the water in a few fluid inclusions from the Zag and Monahans halite, (2) mineralogical characterization of the solid mineral phases associated with the aqueous fluids within the halite, and (3) the first minor element analyses of the fluid itself. A Cameca ims-1270 equipped with a cryo-sample-stage of Hokkaido University was specially prepared for the O and H isotopic measurements. The cryo-sample-stage (Techno. I. S. Corp.) was cooled down to c.a. -190 C using liquid nitrogen at which the aqueous fluid in inclusions was frozen. We excavated the salt crystal surfaces to expose the frozen fluids using a 15 keV Cs+ beam and measured negative secondary ions. The secondary ions from deep craters of approximately 10 m in depth emitted stably but the intensities changed gradually during measurement cycles because of shifting states of charge compensation, resulting in rather poor reproducibility of multiple measurements of standard fluid

  5. Water Exchange Rates and Molecular Mechanism around Aqueous Halide Ions

    SciTech Connect

    Annapureddy, Harsha V.; Dang, Liem X.

    2014-07-17

    Molecular dynamics simulations were performed to systematically study the water-exchange mechanism around aqueous chloride, bromide, and iodide ions. Transition state theory, Grote-Hynes theory, and the reactive flux method were employed to compute water exchange rates. We computed the pressure dependence of rate constants and the corresponding activation volumes to investigate the mechanism of the solvent exchange event. The activation volumes obtained using the transition state theory rate constants are negative for all the three anions, thus indicating an associative mechanism. Contrary to the transition state theory results, activation volumes obtained using rate constants from Grote-Hynes theory and the reactive flux method are positive, thus indicating a dissociative mechanism. The Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences (BES), of the U.S. Department of Energy (DOE) funded this work. Battelle operates Pacific Northwest National Laboratory for DOE. The calculations were carried out using computer resources provided by BES.

  6. Monitoring corrosion and chemistry phenomena in supercritical aqueous systems

    SciTech Connect

    Macdonald, D.D.; Pang, J.; Liu, C.; Kriksunov, L.; Medina, E.; Villa, J.; Bueno, J.

    1994-12-31

    The in situ monitoring of the chemistry and electrochemistry of aqueous heat transport fluids in thermal (nuclear and fossil) power plants is now considered essential if adequate assessment and close control of corrosion and mass transfer phenomena are to be achieved. Because of the elevated temperatures and pressures involved. new sensor technologies are required that are able to measure key parameters under plant operating conditions for extended periods of time. In this paper, the authors outline a research and development program that is designed to develop practical sensors for use in thermal power plants. The current emphasis is on sensors for measuring corrosion potential, pH, the concentrations of oxygen and hydrogen, and the electrochemical noise generated by corrosion processes at temperatures ranging from {approximately}250 C to 500 C. The program is currently at the laboratory stage, but testing of prototype sensors in a coal-fired supercritical power plant in Spain will begin shortly.

  7. Analytical Laboratory Science on the 2009 Mars Science Laboratory (MSL) Mission

    NASA Technical Reports Server (NTRS)

    Mahaffy, P. R.

    2005-01-01

    The Odyssey Missions orbital maps of near surface ice abundance using neutron spectroscopy (Boynton et al., 2002), the Mars Exploration Rover s confirmation of aqueous processing (Squyres et al., 2004), and the Mars Express detailed infrared maps of specific mineral types that were likely formed in aqueous environments (Bibring et al., 2005) have dramatically expanded our tool set for understanding of aqueous processes on Mars. The 2009 Mars Science Laboratory is designed to extend the "follow the water" crosscutting theme of the Mars Exploration Program toward an even more detailed exploration of habitability - the potential of the Mars environment to support life. The next steps in understanding the habitability of Mars are a more detailed in situ analysis of the chemical state of elements such as C, H, O, N, S, P, Ca, and Fe that are essential for terrestrial life. Of particular interest are experiments that establish definitive mineralogy for a wider range of compounds and those that implement a more comprehensive and sensitive search for organic molecules both in the atmosphere and in surface or near surface rocks, soils, and fines. The recent reports of atmospheric methane in the Martian atmosphere make the organics exploration even more compelling. The substantial mass and power resources of MSL combined with its mobility and powerful sample acquisition and processing tools will enable it to locate a variety of near-surface samples and analyze these in some detail. NASA is presently considering the possibility of landing a second MSL rover in 2011.

  8. Suzaku Observes Weak Flares from IGRJ17391-3021 Representing a Common Low-Activity State in this SFXT

    NASA Technical Reports Server (NTRS)

    Bodaghee, A.; Tomsick, J. A.; Rodriquez, J.; Chaty, S.; Pottschmidt, K.; Walter, R.; Romano, P.

    2010-01-01

    We present an analysis of a 37-ks observation of the supergiant fast X-ray transient (SFXT) IGRJ17391 -3021 (=XTEJ1739-302) gathered with Suzaku. The source evolved from quiescence to a low-activity level culminating in three weak flares lasting approx.3 ks each in which the peak luminosity is only a factor of 5 times that of the pre-flare luminosity. The minimum observed luminosity was 1.3 x 10(exp 33) erg/s (d/2.7 kpc)(exp 2) in the 0.5-10 keV range. The weak flares are accompanied by significant changes in the spectral parameters including a column density (N(sub H) = (4.1(+0.4/-0.5)) x 10(exp 22)/sq cm) that is approx.2-9 times the absorption measured during quiescence. Accretion of obscuring clumps of stellar wind material can explain both the small flares and the increase in NH. Placing this observation in the context of the recent Swift monitoring campaign, we find that weak-flaring episodes, or at least epochs of enhanced activity just above the quiescent level but well below the moderately bright or high-luminosity outbursts, represent more than 60+/-5% of all observations in the 0.5-10keV energy range making this the most common state in the emission behavior of IGRJ17391 -3021.

  9. Evaluation of a new geriatric foot versus the Solid Ankle Cushion Heel foot for low-activity amputees.

    PubMed

    Bonnet, Xavier; Adde, Jean N; Blanchard, François; Gedouin-Toquet, Annick; Eveno, Dominique

    2015-04-01

    It is always a challenge to rehabilitate geriatric amputees to perform self-care skills at home with limited ambulation. A new geriatric foot (with a lower effective foot length) has been specifically designed to reduce residual limb stress and to ease the step completion. The aim of this study is to evaluate the benefit of a new geriatric foot versus a Solid Ankle Cushion Heel foot for low-activity persons with transtibial amputation. Crossover study. A total of 12 patients were included in this study. 2-min walking test, Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 questionnaire and pressure socket measurements. The geriatric foot allows for greater patient satisfaction. The maximal pressure was significantly lower in the proximal anterior stump area. No statistical differences were obtained from the 2-min walking test. A geriatric foot designed with a low effective foot length improves the satisfaction and reduces proximal anterior socket pressures for poor-performing persons with transtibial amputation. The development and evaluation of feet specifically designed for geriatric persons with transtibial amputation could improve their specific requirements and satisfaction. © The International Society for Prosthetics and Orthotics 2014.

  10. Issues of low activation brazing of SiC f/SiC composites by using alloys without free silicon

    NASA Astrophysics Data System (ADS)

    Riccardi, B.; Nannetti, C. A.; Petrisor, T.; Woltersdorf, J.; Pippel, E.; Libera, S.; Pilloni, L.

    2004-08-01

    The paper presents a novel low activation brazing technique for SiC f/SiC composites. The brazing alloy does not contain free silicon and is based on the use of a Si-44Cr at.% eutectic and the intermetallic CrSi 2 (melting temperatures 1390 and 1490 °C, respectively). These are advantageous because the melting point is low enough to avoid degradation of the advanced fibres and of the interphases in the composite, and the Si-Cr intermetallics are chemically compatible with silicon carbide. Both the eutectic and the intermetallic were prepared before brazing operations by melting a Si-Cr mixture. The joining was performed under vacuum (about 10 -4 Pa). Systematic investigations of the microstructure and of the nanochemistry (TEM, EELS, ELNES) of the Si-Cr joints reveal that direct chemical Si-Si, Cr-C and Si-Cr bonds across the interface are responsible for the adhesion: the interfaces were proved to be nearly atomically sharp and adhesive. Altogether, this brazing procedure enables joints with sufficient strength and with a microstructure comparable with that of the starting powders to be obtained.

  11. Sensitivity tests of the waste-form-alone design for the low-activity-waste disposal system

    SciTech Connect

    Fayer, M.J.; White, M.D.; Kincaid, C.T.

    1997-09-01

    Computer simulations were performed to assess the performance of the waste-form-alone (WFA) design for the low-activity-waste (LAW) disposal system. In FY 1997, PNNL performed additional simulations for Lockheed Martin Hanford Company (LMHC) to address specific questions about the disposal. LMHC manages the Glass Performance Assessment Project for DOE. The objectives of the additional simulations were to demonstrate the impact of grid resolution, diffusion, fracture flow within the waste form, and consumption of water by the waste form. It was assumed that the waste form would be the only part of the engineered disposal system that inhibits radionuclide release, referred to as WFA assumption. All calculations were performed with the latest version of the STOMP (Subsurface Transport Over Multiple Phases) simulator. Multiple simulations of the WFA disposal were performed to identify parameter and conceptual model sensitivities. The corrosion rate, recharge rate, well interception factor, hydraulic properties, and hydraulic and retardation models were shown to be important. Diffusion was shown to be important for the gravel model of glass but not the soil model. The impact of temperature changes was discussed and determined to be negligible. Water consumption during corrosion was evaluated and found to have a minimal effect on the dose calculations. Fracture flow within the glass was evaluated and found to have only a minimal effect on the dose calculations.

  12. Impact behavior of two low activation steels after irradiation to ˜67 dpa at 430°C

    NASA Astrophysics Data System (ADS)

    Hamilton, M. L.; Schubert, L. E.; Gelles, D. S.

    1998-10-01

    Miniature CVN specimens of four martensitic steels, GA3X, F82H, GA4X and HT9, have been impact tested following irradiation at 430°C to 67 dpa. Comparison of the results with those obtained previously at lower doses indicates that the GA3X and F82H alloys, two primary candidate low activation alloys, exhibit similar behavior following irradiation at 430°C to ˜67 dpa and at 370°C to ˜15 dpa. Virtually no shift in either ductile to brittle transition temperature (DBTT) or upper shelf energy (USE) was observed in the F82H alloy at 67 dpa for either notched or precracked specimens. This absence of a shift in DBTT and USE in F82H compares with a slight increase in DBTT and a slight decrease in USE for GA3X, and much larger degradation in both properties in GA4X and HT9. The shifts in DBTT and USE observed in both GA4X and HT9 were smaller after irradiation at 430°C to ˜67 dpa than after irradiation at 370°C to ˜15 dpa.

  13. Physical, Hydraulic, and Transport Properties of Sediments and Engineered Materials Associated with Hanford Immobilized Low-Activity Waste

    SciTech Connect

    Rockhold, Mark L.; Zhang, Z. F.; Meyer, Philip D.; Thomle, Jonathan N.

    2015-02-28

    Current plans for treatment and disposal of immobilized low-activity waste (ILAW) from Hanford’s underground waste storage tanks include vitrification and storage of the glass waste form in a nearsurface disposal facility. This Integrated Disposal Facility (IDF) is located in the 200 East Area of the Hanford Central Plateau. Performance assessment (PA) of the IDF requires numerical modeling of subsurface flow and reactive transport processes over very long periods (thousands of years). The models used to predict facility performance require parameters describing various physical, hydraulic, and transport properties. This report provides updated estimates of physical, hydraulic, and transport properties and parameters for both near- and far-field materials, intended for use in future IDF PA modeling efforts. Previous work on physical and hydraulic property characterization for earlier IDF PA analyses is reviewed and summarized. For near-field materials, portions of this document and parameter estimates are taken from an earlier data package. For far-field materials, a critical review is provided of methodologies used in previous data packages. Alternative methods are described and associated parameters are provided.

  14. High-throughput design of low-activation, high-strength creep-resistant steels for nuclear-reactor applications

    NASA Astrophysics Data System (ADS)

    Lu, Qi; van der Zwaag, Sybrand; Xu, Wei

    2016-02-01

    Reduced-activation ferritic/martensitic steels are prime candidate materials for structural applications in nuclear power reactors. However, their creep strength is much lower than that of creep-resistant steel developed for conventional fossil-fired power plants as alloying elements with a high neutron activation cannot be used. To improve the creep strength and to maintain a low activation, a high-throughput computational alloy design model coupling thermodynamics, precipitate-coarsening kinetics and an optimization genetic algorithm, is developed. Twelve relevant alloying elements with either low or high activation are considered simultaneously. The activity levels at 0-10 year after the end of irradiation are taken as optimization parameter. The creep-strength values (after exposure for 10 years at 650 °C) are estimated on the basis of the solid-solution strengthening and the precipitation hardening (taking into account precipitate coarsening). Potential alloy compositions leading to a high austenite fraction or a high percentage of undesirable second phase particles are rejected automatically in the optimization cycle. The newly identified alloys have a much higher precipitation hardening and solid-solution strengthening at the same activity level as existing reduced-activation ferritic/martensitic steels.

  15. FlexTouch: An Insulin Pen-Injector with a Low Activation Force Across Different Insulin Formulations, Needle Technologies, and Temperature Conditions.

    PubMed

    Gudiksen, Niels; Hofstätter, Thibaud; Rønn, Birgitte B; Sparre, Thomas

    2017-07-13

    FlexTouch® (Novo Nordisk A/S, Bagsvaerd, Denmark) is a pen-injector with a torque spring mechanism requiring a low activation force. This laboratory-based study compared the activation force of FlexTouch during the injection of insulin with different needles and at temperature conditions within the range at which the device is recommended for use. Using a tensile tester, activation force was measured at maximum dose settings for insulin detemir (100 U/mL) and insulin degludec (100 and 200 U/mL) at standard (23°C ± 5°C), cool (5°C ± 3°C), and warm (30°C ± 2°C) conditions. Activation force was measured with two 32-gauge needles differing in internal diameter at standard conditions. At standard, cool, and warm conditions, estimated mean activation forces with 95% confidence interval were 5.71 newtons (N) (5.63-5.79), 5.94 N (5.83-6.06), and 5.69 N (5.58-5.80) with insulin detemir, 5.53 N (5.45-5.62), 5.56 N (5.44-5.67), and 5.33 N (5.22-5.44) with 100 U/mL insulin degludec, and 5.53 N (5.45-5.61), 5.83 N (5.71-5.94), and 5.56 N (5.45-5.68) with 200 U/mL insulin degludec, respectively. Mean activation forces were observed to be low with very small variability between measurements; however, the differences between insulins and temperature conditions were statistically significant. The activation force required by FlexTouch remained low across all situations tested. The differences between activation force needed with different insulins and temperature conditions were small and unlikely to be clinically meaningful.

  16. [Accreditation of medical laboratories].

    PubMed

    Horváth, Andrea Rita; Ring, Rózsa; Fehér, Miklós; Mikó, Tivadar

    2003-07-27

    In Hungary, the National Accreditation Body was established by government in 1995 as an independent, non-profit organization, and has exclusive rights to accredit, amongst others, medical laboratories. The National Accreditation Body has two Specialist Advisory Committees in the health care sector. One is the Health Care Specialist Advisory Committee that accredits certifying bodies, which deal with certification of hospitals. The other Specialist Advisory Committee for Medical Laboratories is directly involved in accrediting medical laboratory services of health care institutions. The Specialist Advisory Committee for Medical Laboratories is a multidisciplinary peer review group of experts from all disciplines of in vitro diagnostics, i.e. laboratory medicine, microbiology, histopathology and blood banking. At present, the only published International Standard applicable to laboratories is ISO/IEC 17025:1999. Work has been in progress on the official approval of the new ISO 15189 standard, specific to medical laboratories. Until the official approval of the International Standard ISO 15189, as accreditation standard, the Hungarian National Accreditation Body has decided to progress with accreditation by formulating explanatory notes to the ISO/IEC 17025:1999 document, using ISO/FDIS 15189:2000, the European EC4 criteria and CPA (UK) Ltd accreditation standards as guidelines. This harmonized guideline provides 'explanations' that facilitate the application of ISO/IEC 17025:1999 to medical laboratories, and can be used as a checklist for the verification of compliance during the onsite assessment of the laboratory. The harmonized guideline adapted the process model of ISO 9001:2000 to rearrange the main clauses of ISO/IEC 17025:1999. This rearrangement does not only make the guideline compliant with ISO 9001:2000 but also improves understanding for those working in medical laboratories, and facilitates the training and education of laboratory staff. With the

  17. Precision aqueous cleaner for RSRM

    NASA Technical Reports Server (NTRS)

    Hutchens, D. E.; Keen, J. M.; Doan, P. A.; Deweese, C. D.; Burns, H. D., Jr.; Vickers, J. H.

    1993-01-01

    Chlorinated solvents such as freon and 1,1,1 trichloroethane (TCA) are both environmental and physiological hazards which deplete stratospheric ozone. These chemicals are the primary degreasing solvents (vapor, vat, and hand operations) in redesigned solid rocket motor (RSRM) manufacturing. Due to the mandates of the Clean Air Act, substitutes must be identified for RSRM cleaning processes. The initial phase of laboratory testing identified candidate cleaners to replace 1,1,1 trichloroethane for cleaning, potentially reducing annual TCA consumption by 800,000 lbs. This paper describes RSRM testing which elucidated the effects of several interdependent variable including: definition of surface cleanliness criteria, validation of cleaning power of new candidates, the effect of immersion cleaning versus spray cleaning on cleaning, any effect of the cleaner and/or inhibitor upon bondline aging, and compatibility of the cleaners with nonmetallic tooling and processing materials.

  18. The Gran Sasso Laboratory

    NASA Astrophysics Data System (ADS)

    Votano, L.

    2012-09-01

    The Gran Sasso underground laboratory is one of the four national laboratories run by the INFN (Istituto Nazionale di Fisica Nucleare). It is located under the Gran Sasso massif, in central Italy, between the cities of L'Aquila and Teramo, 120 km far from Rome. It is the largest underground laboratory for astroparticle physics in the world and the most advanced in terms of complexity and completeness of its infrastructures. The scientific program at the Gran Sasso National Laboratories (Laboratori Nazionali del Gran Sasso, LNGS)is mainly focused on astroparticle, particle and nuclear physics. The laboratory presently hosts many experiments as well as R&D activities, including world-leading research in the fields of solar neutrinos, accelerator neutrinos (CNGS neutrino beam from CERN to Gran Sasso), dark matter, neutrinoless double-beta decay and nuclear cross-section of astrophysical interest. Associate sciences like earth physics, biology and fundamental physics complement the activities. The laboratory is operated as an international science facility and hosts experiments whose scientific merit is assessed by an international advisory Scientific Committee. A review of the main experiments carried out at LNGS will be given, together with the most recent and relevant scientific results achieved.

  19. Carbon Characterization Laboratory Report

    SciTech Connect

    David Swank; William Windes; D.C. Haggard; David Rohrbaugh; Karen Moore

    2009-03-01

    The newly completed Idaho National Laboratory (INL) Carbon Characterization Laboratory (CCL) is located in Lab-C20 of the Idaho National Laboratory Research Center. This laboratory was established under the Next Generation Nuclear Plant (NGNP) Project to support graphite research and development activities. The CCL is designed to characterize and test carbon-based materials such as graphite, carbon-carbon composites, and silicon-carbide composite materials. The laboratory is fully prepared to measure material properties for nonirradiated carbon-based materials. Plans to establish the laboratory as a radiological facility within the next year are definitive. This laboratory will be modified to accommodate irradiated materials, after which it can be used to perform material property measurements on both irradiated and nonirradiated carbon-based material. Instruments, fixtures, and methods are in place for preirradiation measurements of bulk density, thermal diffusivity, coefficient of thermal expansion, elastic modulus, Young’s modulus, Shear modulus, Poisson ratio, and electrical resistivity. The measurement protocol consists of functional validation, calibration, and automated data acquisition.

  20. Air Force Research Laboratory

    DTIC Science & Technology

    2009-06-08

    Air Force Research Laboratory 8 June 2009 Mr. Leo Marple Ai F R h L b t r orce esearc a ora ory Leo.Marple@wpafb.af.mil DISTRIBUTION STATEMENT A...TITLE AND SUBTITLE Air Force Research Laboratory 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Air Force Research Laboratory ,Wright