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Sample records for measure low-level current

  1. LOW-LEVEL DIRECT CURRENT AMPLIFIER

    DOEpatents

    Kerns, Q.A.

    1959-05-01

    A d-c amplifier is described. Modulation is provided between a d-c signal and an alternating current to give an output signal proportional to the d- c signal. The circuit has high sensitivity and accuracy. (T.R.H.)

  2. Automatic Measurement of Low Level Contamination on Concrete Surfaces

    SciTech Connect

    Tachibana, M.; Itoh, H.; Shimada, T.; Yanagihara, S.

    2002-02-28

    Automatic measurement of radioactivity is necessary for considering cost effectiveness in final radiological survey of building structures in decommissioning nuclear facilities. The RAPID (radiation measuring pilot device for surface contamination) was developed to be applied to automatic measurement of low level contamination on concrete surfaces. The RAPID has a capability to measure contamination with detection limit of 0.14 Bq/cm2 for 60Co in 30 seconds of measurement time and its efficiency is evaluated to be 5 m2/h in a normal measurement option. It was confirmed that low level contamination on concrete surfaces could be surveyed by the RAPID efficiently compared with direct measurement by workers through its actual application.

  3. Low-level measurements of tritium in water.

    PubMed

    Villa, M; Manjón, G

    2004-01-01

    Using a liquid scintillation counter, an experimental procedure for measuring low-level activity concentrations of tritium in environmental water has been developed by our laboratory, using the electrolytic tritium enrichment. Additionally, some quality tests were applied in order to assure the goodness of the method. Well-known water samples collected in the Tagus River (West of Spain) and the Danube River (Bulgaria), both affected by nuclear plant releases, were analysed and results were compared to previous data. The analytical procedure was applied to drinking water samples from the public water supply of Seville and mineral waters from different springs in Spain in order to characterize its origin. Due to the very low levels of tritium in the analysed samples, some results were reported as lower than the minimum detectable activity concentration (MDA). However, the count rate of these measurements was over the background count rate of LS counter in all the cases. For that reason, an exhaustive discussion about the meaning of the MDA, using an experimental essay, was made in order to establish a rigorous criterion that leads to a reliable value in the case of low-level measurements. PMID:15177365

  4. Lightning induced currents in aircraft wiring using low level injection techniques

    NASA Technical Reports Server (NTRS)

    Stevens, E. G.; Jordan, D. T.

    1991-01-01

    Various techniques were studied to predict the transient current induced into aircraft wiring bundles as a result of an aircraft lightning strike. A series of aircraft measurements were carried out together with a theoretical analysis using computer modeling. These tests were applied to various aircraft and also to specially constructed cylinders installed within coaxial return conductor systems. Low level swept frequency CW (carrier waves), low level transient and high level transient injection tests were applied to the aircraft and cylinders. Measurements were made to determine the transfer function between the aircraft drive current and the resulting skin currents and currents induced on the internal wiring. The full threat lightning induced transient currents were extrapolated from the low level data using Fourier transform techniques. The aircraft and cylinders used were constructed from both metallic and CFC (carbon fiber composite) materials. The results show the pulse stretching phenomenon which occurs for CFC materials due to the diffusion of the lightning current through carbon fiber materials. Transmission Line Matrix modeling techniques were used to compare theoretical and measured currents.

  5. Conditions necessary for low-level measurements of reactive oxidants

    SciTech Connect

    Nakareseisoon, S.

    1988-01-01

    Chlorine dioxide and ozone are considered to be the alternatives to chlorine for the disinfection of drinking water supplies and also for the treatment of wastewaters prior to discharge. Chlorine dioxide, under normal circumstances, is reduced to chlorite ion which is toxic. The recommended seven-day suggested no-adverse-response levels (SNARL's) of chlorite ion is 0.007 mg/l (7 ppb). Chlorite ion at these low levels cannot be satisfactorily determined by existing methods, and so, it became necessary to develop an analytical method for determining ppb levels of chlorite ion. Such a method can be developed using differential pulse polarography (DPP). The electrochemical reduction of chlorite ion has been studied between pH 3.7-14 and in an ionic strength range of 0.05-3.0 M. The optimum conditions are pH 4.1-4.4 and an ionic strength of 0.45 M. The current under these conditions is a linear function of chlorite ion concentration ranging from 2.77 {times} 10{sup {minus}7} to 2.80 {times} 10{sup {minus}4} M (19 ppb to 19 ppm). The imprecision is better than {plus minus} 1.0% and {plus minus} 3.4% at concentrations of 2.87 {times} 10{sup {minus}5} M and 1.74 {times} 10{sup {minus}6} M, respectively, with a detection limit of 1 {times} 10{sup {minus}7} M (7 ppb). The rate of ozone decomposition has been studied in highly basic solutions (8-15 NaOH), where ozone becomes stable. The mechanism of ozone regeneration was proposed to explain the observed kinetic and to clarify the contradiction concerning the very slow observed rate of ozone decomposition in basic solution.

  6. MEASUREMENT OF LOW LEVEL AIR TOXICS WITH MODIFIED UV DOAS

    EPA Science Inventory

    To further understand near source impacts, EPA is working to develop open-path optical techniques for spatiotemporal-resolved measurement of air pollutants. Of particular interest is near real time quantification of mobile-source generated CO, Nox and hydrocarbons measured in cl...

  7. Low-level 14C measurements and Accelerator Mass Spectrometry

    SciTech Connect

    Litherland, A.E.; Beukens, R.P.; Zhao, X.-L.; Kieser, W.E.; Gove, H.E.

    2005-09-08

    Accelerator Mass Spectrometry (AMS) and isotope enrichment were used in 1991 to estimate that the 14C content of methane in natural gas was {<=}1.6x10-18 of the total carbon. The low content of 14C in underground hydrocarbons was verified later in the remarkable results from the Borexino test scintillation counter for solar neutrino studies. Since then studies of the 14C background problem have demonstrated that much of the background originally observed in the AMS measurements can, in principle, be eliminated. However, many difficulties and other backgrounds are to be faced as the limit for AMS is pushed still further towards possibly a ratio of < 10-21. These will be discussed.

  8. Application Of The Thermoluminescent Dosemeters For The Measurement Of Low Level Background

    SciTech Connect

    Stochioiu, Ana I.; Sahagia, Maria C.; Mihai, Felicia S.; Tudor, Ion L.; Lupescu, Henrieta I.

    2007-04-23

    The results obtained in the measurement of the low level radiation background by using a thermoluminescent (TL) system, in a former salt mine, designed to be used as an underground laboratory , are presented.

  9. Measurements of low-level prepulse on Nike KrF laser

    NASA Astrophysics Data System (ADS)

    Karasik, Max; Mostovych, A. N.; Lehmberg, R. H.; Chan, Y.; Weaver, J. L.; Obenschain, S. P.

    2005-09-01

    The krypton fluoride (KrF) laser is a leading candidate driver for inertial fusion energy. Some of the current fusion target designs call for targets with thin metallic coatings. These targets could be particularly susceptible to preheat by a low-level laser prepulse. Knowledge of the prepulse can be important in understanding and modeling the behavior of such targets. This paper presents measurements of low-level prepulse on target with the Nike KrF laser. Sources of prepulse are discussed and measurements are performed under several specific laser conditions in order to evaluate the relative contribution of these sources to the overall prepulse. Prepulse is found to be ˜2×10-7 from peak intensity for approximately 120ns prior to the main laser pulse. Prepulse energy density on target is ˜2J/cm2. The first laser amplifier in the time- and angle-multiplexed section of the laser is found to be the dominant source of prepulse.

  10. Current practices for maintaining occupational exposures ALARA at low-level waste disposal sites

    SciTech Connect

    Hadlock, D.E.; Herrington, W.N.; Hooker, C.D.; Murphy, D.W.; Gilchrist, R.L.

    1983-12-01

    The United States Nuclear Regulatory Commission contracted with Pacific Northwest Laboratory (PNL) to provide technical assistance in establishing operational guidelines, with respect to radiation control programs and methods of minimizing occupational radiation exposure, at Low-Level Waste (LLW) disposal sites. The PNL, through site visits, evaluated operations at LLW disposal sites to determine the adequacy of current practices in maintaining occupational exposures as low as is reasonably achievable (ALARA). The data sought included the specifics of: ALARA programs, training programs, external exposure control, internal exposure control, respiratory protection, surveillance, radioactive waste management, facilities and equipment, and external dose analysis. The results of the study indicated the following: The Radiation Protection and ALARA programs at the three commercial LLW disposal sites were observed to be adequate in scope and content compared to similar programs at other types of nuclear facilities. However, it should be noted that there were many areas that could be improved upon to help ensure the health and safety of occupationally exposed individuals.

  11. Ultra low-level tritium measurement using electrolytic enrichment and LSC.

    PubMed

    Morgenstern, Uwe; Taylor, Claude B

    2009-06-01

    We describe an advanced methodology for low-level tritium measurement in regard to calibration, electrolytic tritium enrichment, liquid scintillation counting (LSC) measurement, and prevention of sample contamination. Details are given on enrichment parameters and electrode processes for optimisation of enrichment reproducibility and on optimisation of LSC stability. Intercomparison results demonstrate high accuracy of the tritium measurement system. The use of accurate tritium data for groundwater dating in the southern hemisphere is demonstrated with data from several groundwater systems of New Zealand.

  12. Ultra-low-level measurements of 3H and 14C in wines and champagne

    NASA Astrophysics Data System (ADS)

    Scherer, U. W.; Jacobi, M.; Castillo, J.; Förstel, D. H.

    Methods to measure low concentrations of tritium and radiocarbon in wine and champagne, respectively, have been tested by using liquid scintillation counting after chemical sample processing. It could be shown that tritium activity was too low to be measured by our standard low-level liquid scintillation counter, WALLAC Guardian 1414. Positive results could be achieved when using a WALLAC Quantulus. The methods will be established as standard methods to detect forgeries and to improve consumer safety.

  13. A unique automation platform for measuring low level radioactivity in metabolite identification studies.

    PubMed

    Krauser, Joel; Walles, Markus; Wolf, Thierry; Graf, Daniel; Swart, Piet

    2012-01-01

    Generation and interpretation of biotransformation data on drugs, i.e. identification of physiologically relevant metabolites, defining metabolic pathways and elucidation of metabolite structures, have become increasingly important to the drug development process. Profiling using (14)C or (3)H radiolabel is defined as the chromatographic separation and quantification of drug-related material in a given biological sample derived from an in vitro, preclinical in vivo or clinical study. Metabolite profiling is a very time intensive activity, particularly for preclinical in vivo or clinical studies which have defined limitations on radiation burden and exposure levels. A clear gap exists for certain studies which do not require specialized high volume automation technologies, yet these studies would still clearly benefit from automation. Use of radiolabeled compounds in preclinical and clinical ADME studies, specifically for metabolite profiling and identification are a very good example. The current lack of automation for measuring low level radioactivity in metabolite profiling requires substantial capacity, personal attention and resources from laboratory scientists. To help address these challenges and improve efficiency, we have innovated, developed and implemented a novel and flexible automation platform that integrates a robotic plate handling platform, HPLC or UPLC system, mass spectrometer and an automated fraction collector.

  14. Measurement and interpretation of low levels of dissolved oxygen in ground water

    USGS Publications Warehouse

    White, A.F.; Peterson, M.L.; Solbau, R.D.

    1990-01-01

    A Rhodazine-D colorimetric technique was adapted to measure low-level dissolved oxygen concentrations in ground water. Prepared samples containing between 0 and 8.0 ??moles L-1 dissolved oxygen in equilibrium with known gas mixtures produced linear spectrophotometric absorbance with a lower detection limit of 0.2 ??moles L-1. Excellent reproducibility was found for solutions ranging in composition from deionized water to sea water with chemical interferences detected only for easily reduced metal species such as ferric ion, cupric ion, and hexavalent chromium. Such effects were correctable based on parallel reaction stoichiometries relative to oxygen. The technique, coupled with a downhole wire line tool, permitted low-level monitoring of dissolved oxygen in wells at the selenium-contaminated Kesterson Reservoir in California. Results indicated a close association between low but measurable dissolved oxygen concentrations and mobility of oxidized forms of selenium. -from Authors

  15. Measurement of Low Level Explosives Reaction in Gauged Multi-Dimensional Steven Impact Tests

    SciTech Connect

    Niles, A M; Garcia, F; Greenwood, D W; Forbes, J W; Tarver, C M; Chidester, S K; Garza, R G; Swizter, L L

    2001-05-31

    The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and also be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times. Carbon resistor gauges indicated late time low level reactions 200-540 {micro}s after projectile impact, creating 0.39-2.00 kb peak shocks centered in PBX 9501 explosives discs and a 0.60 kb peak shock in a LX-04 disk. Steven Test modeling results, based on ignition and growth criteria, are presented for two PBX 9501 scenarios: one with projectile impact velocity just under threshold (51 m/s) and one with projectile impact velocity just over threshold (55 m/s). Modeling results are presented and compared to experimental data.

  16. Measurements of activation induced by environmental neutrons using ultra low-level gamma-ray spectrometry.

    PubMed

    Martínez Canet, M J; Hult, M; Köhler, M; Johnston, P N

    2000-03-01

    The flux of environmental neutrons is being studied by activation of metal discs of selected elements. Near the earth's surface the total neutron flux is in the order of 10(-2) cm(-2)s(-1), which gives induced activities of a few mBq in the discs. Initial results from this technique, involving activation at ground level for several materials (W, Au, Ta, In, Re, Sm, Dy and Mn) and ultra low-level gamma-ray spectrometry in an underground laboratory located at 500 m.w.e., are presented. Diffusion of environmental neutrons in water is also measured by activation of gold at different depths.

  17. Experience gained through the intercalibration programme for low-level alpha-spectrometric measurements

    NASA Astrophysics Data System (ADS)

    Fukai, R.; Ballestra, S.; Bojanowski, R.; Vas, D.

    1984-06-01

    For the past decade the International Laboratory of Marine Radioactivity at Monaco has been engaged in organizing several intercalibration exercises of radionuclide measurements on various matrices of marine origin. The comparisons of the results obtained in different series of the intercalibration exeercises show that, while the comparability of the plutonium measurements has considerably improved in recent years, the americium measurements do not yet compare favourably transuranic measurements, especially those for americium at low-levels, should still be continued in the future. These series of the intercalibration produced valuable reference materials for which probable concentrations of transuranic nuclides are known. The importance of intralaboratory analytical quality control by using these materials are emphasized for achieving sufficiently consistent and reliable results.

  18. Recent accomplishments in low-level radioactive waste measurement at Los Alamos

    SciTech Connect

    Midkiff, W.S.; Attrep, M.; Covey, J.R.

    1994-03-01

    Is Los Alamos National Laboratory (LANL) the only laboratory that has difficulty measuring low concentrations of alpha radioactivity in wastewater, or do the rest of the nation`s laboratories just not realize the lack of precision/accuracy in its own measurements? DOE Order 5400.5 sets 30 pCi/L total alpha as a goal for effluent discharge. The State of Colorado requires 0.05 pCi/L. The EPA is considering standards in this range for drinking water and therefore, presumably in treated wastewater effluent. How reasonable are these limits with respect to ease and precision/accuracy of routine measurements and real risk to human health and environmental protection? After reviewing the constraints of various analytical methods, the paper describes a method using {sup 236}Pu and {sup 243}Am as traces to determine low levels of alpha in water samples.

  19. Combustion Methods for Measuring Low Levels of Carbon in Nickel, Copper, Silver, and Gold

    NASA Astrophysics Data System (ADS)

    Jacobson, Nathan S.; Savadkouei, Kayvon; Morin, Christophe; Fenstad, Jo; Copland, Evan H.

    2016-09-01

    Laboratory studies and a literature search indicate that there is no definitive procedure for combustion analysis of low levels of carbon in Cu, Ag, and Au. Literature data disagree by one to two orders of magnitude for solubility of carbon in Cu, near the melting point. Data for Ag and Au are very limited. This study develops a procedure for combustion analysis of ppm levels of carbon in high-purity Ni, Cu, Ag, and Au samples. For comparison, each sample is measured with glow discharge mass spectrometry. The study begins with Ni, as the procedure for this material is fairly well established. For the other metals, an optimum accelerator and sample-to-accelerate weight ratio is developed. Fine particle copper is a suitable accelerator for Cu and Ag samples, and also shows potential for Au samples

  20. Fast Scanning Single Collector ICP-MS for Low Level Isotope Ratio Measurements

    NASA Astrophysics Data System (ADS)

    Newman, K.; Georg, B.

    2010-12-01

    Multiple collector (MC)-ICP-MS is recognized as a workhorse in the field of isotope ratio measurements. With its unrivalled precision, high sample throughput and multi-element coverage, MC-ICPMS has opened up new areas of study in earth, environmental and biological sciences. However, SC-ICP-MS is fit for purpose for many applications where sample amount is limited and fractionations are relatively large. To compensate for the inherent ion beam instability associated with the ICP ion source, fast scanning magnetic sector instruments are used. Here, we describe and discuss the use of the Nu Attom SC-ICP-MS for low level isotope ratio measurements. The Nu Attom is a double focusing magnetic sector mass spectrometer with unique fast scanning capabilities. Deflectors located at the entrance and exit of the flight tube are used to alter the effective magnet radius by changing the ion trajectory. This enables a fast electrostatic scan over a mass range of approximately 40%. In contrast to other fast scanning magnetic sector instruments, there is no change in the ion energy which may introduce additional mass bias effects. The Nu Attom also has fully adjustable source and collector slits. This facilitates measurements in medium mass resolution (R=1500-2500), whilst maintaining a flat topped peak necessary for precise isotope ratio measurements. The potential applications of the Nu Attom in isotope ratio measurements will be explored.

  1. Low-Level Plutonium Bioassay Measurements at the Lawrence Livermore National Laboratory

    SciTech Connect

    Hamilton, T; Brown, T; Hickman, D; Marchetti, A; Williams, R; Kehl, S

    2007-06-18

    Plutonium-239 ({sup 239}Pu) and plutonium-240 ({sup 240}Pu) are important alpha emitting radionuclides contained in radioactive debris from nuclear weapons testing. {sup 239}Pu and {sup 240}Pu are long-lived radionuclides with half-lives of 24,400 years and 6580 years, respectively. Concerns over human exposure to plutonium stem from knowledge about the persistence of plutonium isotopes in the environment and the high relative effectiveness of alpha-radiation to cause potential harm to cells once incorporated into the human body. In vitro bioassay tests have been developed to assess uptakes of plutonium based on measured urinary excretion patterns and modeled metabolic behaviors of the absorbed radionuclides. Systemic plutonium absorbed by the deep lung or from the gastrointestinal tract after ingestion is either excreted or distributed to other organs, primarily to the liver and skeleton, where it is retained for biological half-times of around 20 and 50 years, respectively. Dose assessment and atoll rehabilitation programs in the Marshall Islands have historically given special consideration to residual concentrations of plutonium in the environment even though the predicted dose from inhalation and/or ingestion of plutonium accounts for less than 5% of the annual effective dose from exposure to fallout contamination. Scientists from the Lawrence Livermore National Laboratory (LLNL) have developed a state-of-the-art bioassay test to assess urinary excretion rates of plutonium from Marshallese populations. This new heavy-isotope measurement system is based on Accelerator Mass Spectrometry (AMS). The AMS system at LLNL far exceeds the standard measurement requirements established under the latest United States Department of Energy (DOE) regulation, 10CFR 835, for occupational monitoring of plutonium, and offers several advantages over classical as well as competing new technologies for low-level detection and measurement of plutonium isotopes. The United States

  2. Measurement of water potential in low-level waste management. [Shallow Land Burial

    SciTech Connect

    Jones, T. L.; Gee, G. W.; Kirkham, R. R.; Gibson, D. D.

    1982-08-01

    The measurement of soil water is important to the shallow land burial of low-level waste. Soil water flow is the principle mechanism of radionuclide transport, allows the establishment of stabilizing vegetation and also governs the dissolution and release rates of the waste. This report focuses on the measurement of soil water potential and provides an evaluation of several field instruments that are available for use to monitor waste burial sites located in arid region soils. The theoretical concept of water potential is introduced and its relationship to water content and soil water flow is discussed. Next, four major areas of soils research are presented in terms of their dependence on the water potential concept. There are four basic types of sensors used to measure soil water potential. These are: (1) tensiometers; (2) soil psychrometers; (3) electrical resistance blocks; and (4) heat dissipation probes. Tensiometers are designed to measure the soil water potential directly by measuring the soil water pressure. Monitoring efforts at burial sites require measurements of soil water over long time periods. They also require measurements at key locations such as waste-soil interfaces and within any barrier system installed. Electrical resistance blocks are well suited for these types of measurements. The measurement of soil water potential can be a difficult task. There are several sensors commercially available; however, each has its own limitations. It is important to carefully select the appropriate sensor for the job. The accuracy, range, calibration, and stability of the sensor must be carefully considered. This study suggests that for waste management activities, the choice of sensor will be the tensiometer for precise soil characterization studies and the electrical resistance block for long term monitoring programs. (DMC)

  3. Precision Measurement of Low-Level Radioactivity in Environmental and Forensic Samples

    NASA Astrophysics Data System (ADS)

    Pibida, Leticia

    2003-04-01

    A Resonance Ionization Mass Spectrometry (RIMS) system at the National Institute of Standards and Technology (NIST) has been developed for low-level measurements in environmental and forensic samples. The system was compared to a similar system at Pacific Northwest National Laboratory (PNNL). Efficiency and selectivity measurements were performed with both systems and compared to conventional thermal ionization mass spectrometry (TIMS). Determination of radio-cesium isotopic ratios were performed using a single-resonance excitation at 852 nm with an extended cavity diode laser followed by photoionization with the 488 nm line of an argon ion laser. Optical selectivity of more than 2 orders of magnitude against stable ^133Cs was attained for ^135Cs and ^137Cs for both systems, with an overall selectivity of 10^9 for the PNNL system and 10^8 for the NIST system. Overall efficiencies of 2 x 10-6 and 5 x 10-7 were measured for the PNNL and NIST systems, respectively. Measurements to determine the chronological age of a nuclear burn-up sample have been performed using both RIMS systems as well as TIMS. Initial measurements on the NIST SRM 4354 lake sediment sample were performed with the system at NIST. Atomization behavior of the graphite furnace and overall efficiency were measured for different sample preparations, and an approximate value for the ^133 Cs content in the sediment of approximately 4 x 10^14 atoms/g was obtained. TIMS measurements were also performed on the same sample, but barium isobaric interference prevented the extraction of information on the radio-cesium content. Work to improve the efficiency of the system and measurement of different radio-nuclides in different types of samples is in progress.

  4. Low-level 14C methane oxidation rate measurements modified for remote field settings

    NASA Astrophysics Data System (ADS)

    Pack, M. A.; Pohlman, J.; Ruppel, C. D.; Xu, X.

    2012-12-01

    Aerobic methane oxidation limits atmospheric methane emissions from degraded subsea permafrost and dissociated methane hydrates in high latitude oceans. Methane oxidation rate measurements are a crucial tool for investigating the efficacy of this process, but are logistically challenging when working on small research vessels in remote settings. We modified a low-level 14C-CH4 oxidation rate measurement for use in the Beaufort Sea above hydrate bearing sediments during August 2012. Application of the more common 3H-CH4 rate measurement that uses 106 times more radioactivity was not practical because the R/V Ukpik cannot accommodate a radiation van. The low-level 14C measurement does not require a radiation van, but careful isolation of the 14C-label is essential to avoid contaminating natural abundance 14C measurements. We used 14C-CH4 with a total activity of 1.1 μCi, which is far below the 100 μCi permitting level. In addition, we modified field procedures to simplify and shorten sample processing. The original low-level 14C-CH4 method requires 6 steps in the field: (1) collect water samples in glass serum bottles, (2) inject 14C-CH4 into bottles, (3) incubate for 24 hours, (4) filter to separate the methanotrophic bacterial cells from the aqueous sample, (5) kill the filtrate with sodium hydroxide (NaOH), and (6) purge with nitrogen to remove unused 14C-CH4. Onshore, the 14C-CH4 respired to carbon dioxide or incorporated into cell material by methanotrophic bacteria during incubation is quantified by accelerator mass spectrometry (AMS). We conducted an experiment to test the possibility of storing samples for purging and filtering back onshore (steps 4 and 6). We subjected a series of water samples to steps 1-3 & 5, and preserved with mercuric chloride (HgCl2) instead of NaOH because HgCl2 is less likely to break down cell material during storage. The 14C-content of the carbon dioxide in samples preserved with HgCl2 and stored for up to 2 weeks was stable

  5. Measurement and reduction of low-level radon background in the KATRIN experiment

    SciTech Connect

    Fränkle, F. M.

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next generation, model independent, large scale experiment to determine the mass of the electron anti-neutrino by investigating the kinematics of tritium beta decay with a sensitivity of 200 meV/c{sup 2}. The measurement setup consists of a high luminosity windowless gaseous molecular tritium source (WGTS), a differential and cryogenic pumped electron transport and tritium retention section, a tandem spectrometer section (pre-spectrometer and main spectrometer) for energy analysis, followed by a detector system for counting transmitted beta decay electrons. Measurements performed at the KATRIN pre-spectrometer test setup showed that the decay of radon (Rn) atoms in the volume of the KATRIN spectrometers is a major background source. Rn atoms from low-level radon emanation of materials inside the vacuum region of the KATRIN spectrometers are able to penetrate deep into the magnetic flux tube so that the alpha decay of Rn contributes to the background. Of particular importance are electrons emitted in processes accompanying the Rn alpha decay, such as shake-off, internal conversion of excited levels in the Rn daughter atoms and Auger electrons. Lowenergy electrons (< 100 eV) directly contribute to the background in the signal region. High-energy electrons can be stored magnetically inside the volume of the spectrometer and are able to create thousands of secondary electrons via subsequent ionization processes with residual gas molecules. In order to reduce the Rn induced background different active and passive counter measures were developed and tested. This proceeding will give an overview on Rn sources within the KATRIN spectrometer, describes how Rn decays inside the spectrometer produce background events at the detector and presents different counter measures to reduce the Rn induced background.

  6. Gross Alpha Beta Radioactivity in Air Filters Measured by Ultra Low Level α/β Counter

    NASA Astrophysics Data System (ADS)

    Cfarku, Florinda; Bylyku, Elida; Deda, Antoneta; Dhoqina, Polikron; Bakiu, Erjona; Perpunja, Flamur

    2010-01-01

    Study of radioactivity in air as very important for life is done regularly using different methods in every country. As a result of nuclear reactors, atomic centrals, institutions and laboratories, which use the radioactivity substances in open or closed sources, there are a lot radioactive wastes. Mixing of these wastes after treatment with rivers and lakes waters makes very important control of radioactivity. At the other side nuclear and radiological accidents are another source of the contamination of air and water. Due to their radio toxicity, especially those of Sr90, Pu239, etc. a contamination hazard for human begins exist even at low concentration levels. Measurements of radioactivity in air have been performed in many parts of the world mostly for assessment of the doses and risk resulting from consuming air. In this study we present the results of international comparison organized by IAEA Vienna, Austria for the air filters spiked with unknown Alpha and Beta Activity. For the calibration of system we used the same filters spiked: a) with Pu-239 as alpha source; b) Sr-90 as beta source and also the blank filter. The measurements of air filter samples after calibration of the system are done with Ultra Low Level α/β Counter (MPC 9604) Protean Instrument Corporation. The high sensitivity of the system for the determination of the Gross Alpha and Beta activity makes sure detection of low values activity of air filters. Our laboratory results are: Aα = (0.19±0.01) Bq/filter and Aα (IAEA) = (0.17±0.009) Bq/filter; Aβ = (0.33±0.009) Bq/filter and Aβ (IAEA) = (0.29±0.01) Bq/filter. As it seems our results are in good agreement with reference values given by IAEA (International Atomic Energy Agency).

  7. Radionuclide adsorption distribution coefficients measured in Hanford sediments for the low level waste performance assessment project

    SciTech Connect

    Kaplan, D.I.; Serne, R.J.; Owen, A.T.

    1996-08-01

    Preliminary modeling efforts for the Hanford Site`s Low Level Waste-Performance Assessment (LLW PA) identified {sup 129}I, {sup 237}Np, {sup 79}Se, {sup 99}Tc, and {sup 234},{sup 235},{sup 238}U as posing the greatest potential health hazard. It was also determined that the outcome of these simulations was very sensitive to the parameter describing the extent to which radionuclides sorb to the subsurface matrix, i.e., the distribution coefficient (K{sub d}). The distribution coefficient is a ratio of the radionuclide concentration associated with the solid phase to that in the liquid phase. The objectives of this study were to (1) measure iodine, neptunium, technetium, and uranium K{sub d} values using laboratory conditions similar to those expected at the LLW PA disposal site, and (2) evaluate the effect of selected environmental parameters, such as pH, ionic strength, moisture concentration, and radio nuclide concentration, on K{sub d} values of selected radionuclides. It is the intent of these studies to develop technically defensible K{sub d} values for the PA. The approach taken throughout these studies was to measure the key radio nuclide K{sub d} values as a function of several environmental parameters likely to affect their values. Such an approach provides technical defensibility by identifying the mechanisms responsible for trends in K{sub d} values. Additionally, such studies provide valuable guidance regarding the range of K{sub d} values likely to be encountered in the proposed disposal site.

  8. The dark art of light measurement: accurate radiometry for low-level light therapy.

    PubMed

    Hadis, Mohammed A; Zainal, Siti A; Holder, Michelle J; Carroll, James D; Cooper, Paul R; Milward, Michael R; Palin, William M

    2016-05-01

    Lasers and light-emitting diodes are used for a range of biomedical applications with many studies reporting their beneficial effects. However, three main concerns exist regarding much of the low-level light therapy (LLLT) or photobiomodulation literature; (1) incomplete, inaccurate and unverified irradiation parameters, (2) miscalculation of 'dose,' and (3) the misuse of appropriate light property terminology. The aim of this systematic review was to assess where, and to what extent, these inadequacies exist and to provide an overview of 'best practice' in light measurement methods and importance of correct light measurement. A review of recent relevant literature was performed in PubMed using the terms LLLT and photobiomodulation (March 2014-March 2015) to investigate the contemporary information available in LLLT and photobiomodulation literature in terms of reporting light properties and irradiation parameters. A total of 74 articles formed the basis of this systematic review. Although most articles reported beneficial effects following LLLT, the majority contained no information in terms of how light was measured (73%) and relied on manufacturer-stated values. For all papers reviewed, missing information for specific light parameters included wavelength (3%), light source type (8%), power (41%), pulse frequency (52%), beam area (40%), irradiance (43%), exposure time (16%), radiant energy (74%) and fluence (16%). Frequent use of incorrect terminology was also observed within the reviewed literature. A poor understanding of photophysics is evident as a significant number of papers neglected to report or misreported important radiometric data. These errors affect repeatability and reliability of studies shared between scientists, manufacturers and clinicians and could degrade efficacy of patient treatments. Researchers need a physicist or appropriately skilled engineer on the team, and manuscript reviewers should reject papers that do not report beam measurement

  9. The dark art of light measurement: accurate radiometry for low-level light therapy.

    PubMed

    Hadis, Mohammed A; Zainal, Siti A; Holder, Michelle J; Carroll, James D; Cooper, Paul R; Milward, Michael R; Palin, William M

    2016-05-01

    Lasers and light-emitting diodes are used for a range of biomedical applications with many studies reporting their beneficial effects. However, three main concerns exist regarding much of the low-level light therapy (LLLT) or photobiomodulation literature; (1) incomplete, inaccurate and unverified irradiation parameters, (2) miscalculation of 'dose,' and (3) the misuse of appropriate light property terminology. The aim of this systematic review was to assess where, and to what extent, these inadequacies exist and to provide an overview of 'best practice' in light measurement methods and importance of correct light measurement. A review of recent relevant literature was performed in PubMed using the terms LLLT and photobiomodulation (March 2014-March 2015) to investigate the contemporary information available in LLLT and photobiomodulation literature in terms of reporting light properties and irradiation parameters. A total of 74 articles formed the basis of this systematic review. Although most articles reported beneficial effects following LLLT, the majority contained no information in terms of how light was measured (73%) and relied on manufacturer-stated values. For all papers reviewed, missing information for specific light parameters included wavelength (3%), light source type (8%), power (41%), pulse frequency (52%), beam area (40%), irradiance (43%), exposure time (16%), radiant energy (74%) and fluence (16%). Frequent use of incorrect terminology was also observed within the reviewed literature. A poor understanding of photophysics is evident as a significant number of papers neglected to report or misreported important radiometric data. These errors affect repeatability and reliability of studies shared between scientists, manufacturers and clinicians and could degrade efficacy of patient treatments. Researchers need a physicist or appropriately skilled engineer on the team, and manuscript reviewers should reject papers that do not report beam measurement

  10. A UK comparison for measurements of low levels of gamma-emitters in waste drums.

    PubMed

    Dean, Julian

    2009-05-01

    Much of the work of the UK nuclear industry is now concerned with decommissioning many of the existing power stations and other facilities. An important aspect of this work is the accurate measurement of low levels of radioactivity in waste forms such as building materials in order that these materials can be assigned to the correct waste streams. This has led to a call for suitable standards and reference materials, and the specific needs of UK users were identified at an NPL workshop in 2005. One of the highest priorities was for 'soft waste' spiked with gamma-emitters in a 200 L drum format, with an activity concentration of just under 0.4 Bq g(-1). In response, NPL prepared a single reference drum meeting this specification. The low density was achieved by loading the drum with plastic bottles, each partially loaded with ion-exchange resin. The resin in each bottle had been previously spiked with a mixture of (241)Am, (137)Cs and (60)Co, all traceable to national standards. The drum would be used primarily as the basis of a comparison exercise, but feedback on its usefulness as a calibration standard would also be sought. The drum was measured by 17 radioassay groups at 15 UK sites. The monitors used were mostly commercial gamma-spectrometry systems designed to accommodate waste drums. Some groups measured the drum on more than one monitor and some used more than one efficiency calibration. Many of the groups used mathematical modelling to derive their efficiencies. The results of the exercise were discussed at a second NPL workshop (2007), after which the participants were allowed to submit supplementary or replacement results (with reasons for any changes clearly stated). In total, 88 results were submitted. A total of 51 results were in agreement with the NPL values; of the remaining results, 24 were explained by the participants concerned (or were revised to provide supplementary values), but the other 13 results were either clearly discrepant or

  11. Unreviewed Disposal Question Evaluation: Impact of New Information since 2008 PA on Current Low-Level Solid Waste Operations

    SciTech Connect

    Flach, G.; Smith, F.; Hamm, L.; Butcher, T.

    2014-10-06

    Solid low-level waste disposal operations are controlled in part by an E-Area Low-Level Waste Facility (ELLWF) Performance Assessment (PA) that was completed by the Savannah River National Laboratory (SRNL) in 2008 (WSRC 2008). Since this baseline analysis, new information pertinent to disposal operations has been identified as a natural outcome of ongoing PA maintenance activities and continuous improvement in model simulation techniques (Flach 2013). An Unreviewed Disposal Question (UDQ) Screening (Attachment 1) has been initiated regarding the continued ability of the ELLWF to meet Department of Energy (DOE) Order 435.1 performance objectives in light of new PA items and data identified since completion of the original UDQ Evaluation (UDQE). The present UDQE assesses the ability of Solid Waste (SW) to meet performance objectives by estimating the influence of new information items on a recent sum-of-fractions (SOF) snapshot for each currently active E-Area low-level waste disposal unit. A final SOF, as impacted by this new information, is projected based on the assumptions that the current disposal limits, Waste Information Tracking System (WITS) administrative controls, and waste stream composition remain unchanged through disposal unit operational closure (Year 2025). Revision 1 of this UDQE addresses the following new PA items and data identified since completion of the original UDQE report in 2013: New Kd values for iodine, radium and uranium; Elimination of cellulose degradation product (CDP) factors; Updated radionuclide data; Changes in transport behavior of mobile radionuclides; Potential delay in interim closure beyond 2025; and Component-in-grout (CIG) plume interaction correction. Consideration of new information relative to the 2008 PA baseline generally indicates greater confidence that PA performance objectives will be met than indicated by current SOF metrics. For SLIT9, the previous prohibition of non-crushable containers in revision 0

  12. Low level measurements of natural radionuclides in soil samples around a coal-fired power plant

    NASA Astrophysics Data System (ADS)

    Rosner, G.; Bunzl, K.; Hötzl, H.; Winkler, R.

    1984-06-01

    To detect a possible contribution of airborne radioactivity from stack effluents to the soil radioactivity, several radionuclides in the soil around a coal-fired power plant have been determined. A plant situated in a rural region of Bavaria was selected to minimize contributions from other civilisatory sources. The soil sampling network consisted of 5 concentric circles with diameters between 0.4 and 5.2 km around the plant, 16 sampling points being distributed regularly on each circle. Radiochemical analysis techniques for 210Pb and 210Po in soil samples of several grams had to be developed. They include a wet dissolution procedure, simultaneous precipitation of lead and polonium as the sulfides, purification via lead sulfate, counting of the lead as the chromate in a low-level beta counter and alpha spectrometric determination of the 210Po in a gridded ionization chamber. The 238U, 226Ra, 232Th and 40K were counted by low level gamma spectrometry. Specific activities found were in the range of 0.7 to 2.0 pCi g -1 for 210Pb and 0.3 to 1.6 pCi g -1 for 226Ra. The distribution patterns of 210Po and 210Pb around the plant were found to be similar. They were different, however, from that of 226Ra. The highest 210Pb/ 226Ra activity ratio was 3.9 at a distance of 0.76 km SSE from the plant. Nevertheless, the evidence is not considered to be sufficient to attribute these observations unambiguously to plant releases.

  13. Improvements on Low Level Activity Gamma Measurements and X-ray Spectrometry at the CEA-MADERE Measurement Platform

    NASA Astrophysics Data System (ADS)

    Sergeyeva, Victoria; Domergue, Christophe; Destouches, Christophe; Girard, Jean Michel; Philibert, Hervé; Bonora, Jonathan; Thiollay, Nicolas; Lyoussi, Abdallah

    2016-02-01

    The CEA MADERE platform (Measurement Applied to DosimEtry in REactors) is a part of the Instrumentation Sensors and Dosimetry Laboratory (LDCI). This facility is dedicated to the specific activity measurements of solid and radioactive samples using Gamma and X-ray spectrometry. MADERE is a high-performance facility devoted to neutron dosimetry for experimental programs performed in CEA and for the irradiation surveillance programmes of PWR vessels. The MADERE platform is engaged in a continuous improvement process. Recently, two High Efficiency diodes have been integrated to the MADERE platform in order to manage the accurate low level activity measurements (few Bq per sample). This new equipment provides a good level of efficiency over the energy range from 60 keV to 2 MeV. The background continuum is reduced due to the use of a Ultra Low Background (ULB) lead shielding. Relative and absolute X-ray measurement techniques have been improved in order to facilitate absolute rhodium activity measurement (Rh103m) on solid samples. Additional efforts have been made to increase the accuracy of the relative niobium (Nb93m) activity measurement technique. The way of setting up an absolute measurement method for niobium is under investigation. After a presentation of the MADERE's measurement devices, this paper focuses on the technological options taken into account for the design of high efficiency measurement devices. Then, studies performed on X-ray measurement techniques are presented. Some details about the calculation of uncertainties and correction factors are also mentioned. Finally, future research and development axes are exposed.

  14. Low-level environmental lead exposure and intellectual impairment in children--the current concepts of risk assessment.

    PubMed

    Jakubowski, Marek

    2011-03-01

    Lead is an environmental contaminant. The majority of epidemiological research on the health effects of lead has been focused on children, because they are more vulnerable to lead than adults. In children, an elevated blood lead (B-Pb) is associated with reduced Intelligence Quotient (IQ) score. This paper summarizes the current opinions on the assessment of the health risk connected with the children's environmental exposure to lead. The B-Pb level of concern of 100 μg/l proposed by the US Centers of Disease Control in 1991 was for a long time accepted as the guideline value. In the meantime there has been a significant worldwide decrease of B-Pb levels in children and present geometric mean values in the European countries range from 20 to 30 μg/l. The recent analyses of the association of intelligence test scores and B-Pb levels have revealed that the steepest declines in IQ occur at blood levels < 100 μg/l and that no threshold below which lead does not cause neurodevelopmental toxicity can be defended. European Food Safety Authority (EFSA) concluded in 2010, on the basis of results of Benchmark Dose (BMD) analysis, that an increase in B-Pb of 12 μg/l (BMDL₀₁) could decrease the IQ score by one point. It seems that this value can be used as a "unit risk" to calculate the possible decrease of IQ and, consequently, influence of the low-level exposure to lead (< 100 μg/l) on the health and socioeconomic status of the exposed population.

  15. Low-level measurements of Ra-226/Rn-222 by pulse ionization chambers

    NASA Astrophysics Data System (ADS)

    El-Daoushy, Fand; Garcia-Tenorio, Rafael

    1988-10-01

    Characteristics of two ionization chambers have been studied and the chambers utilized for 226Ra/ 222Rn measurements for more than ten years. The results obtained show that coating of internal surfaces with a pure and thin Ag-layer enhances the background of ionization chambers in spite of some improvements at the early stages of operation. In addition to previously known parameters influencing the accuracy in routine measurements, new correction factors are suggested. 226Ra impurities in the body of ionization chambers are found to act not only as a permanent, but also as a temperature-dependent source of background. Earlier accuracies of 226Ra/ 222Rn measurements have been considerably improved by assuring long-term mechanical and thermal stability of the ionization chambers.

  16. Advanced Quadrupole Ion Trap Instrumentation for Low Level Vehicle Emissions Measurements

    SciTech Connect

    McLuckey, S.A.

    1997-01-01

    Quadrupole ion trap mass spectrometry has been evaluated for its potential use in vehicle emissions measurements in vehicle test facilities as an analyzer for the top 15 compounds contributing to smog generation. A variety of ionization methods were explored including ion trap in situ chemical ionization, atmospheric sampling glow discharge ionization, and nitric oxide chemical ionization in a glow discharge ionization source coupled with anion trap mass spectrometer. Emphasis was placed on the determination of hydrocarbons and oxygenated hydrocarbons at parts per million to parts per billion levels. Ion trap in situ water chemical ionization and atmospheric sampling glow discharge ionization were both shown to be amendable to the analysis of arenes, alcohols, aldehydes and, to some degree, alkenes. Atmospheric sampling glow discharge also generated molecular ions of methy-t-butyl ether (MTBE). Neither of these ionization methods, however, were found to generate diagnostic ions for the alkanes. Nitric oxide chemical ionization, on the other hand, was found to yield diagnostic ions for alkanes, alkenes, arenes, alcohols, aldehydes, and MTBE. The ability to measure a variety of hydrocarbons present at roughly 15 parts per billion at measurement rates of 3 Hz was demonstrated. All of the ions with potential to serve as parent ions in a tandem mass spectrometry experiment were found to yield parent-to-product conversion efficiencies greater than 75%. The flexibility afforded to the ion trap by use of tailored wave-forms applied to the end-caps allows parallel monitoring schemes to be devised that provide many of the advantages of tandem mass spectrometry without major loss in measurement rate. A large loss in measurement rate would ordinarily result from the use of conventional tandem mass spectrometry experiments carried out in series for a large number of targeted components. These results have demonstrated that the ion trap has an excellent combination of

  17. An outdoor radon survey and minimizing the uncertainties in low level measurements using CR-39 detectors.

    PubMed

    Gunning, G A; Pollard, D; Finch, E C

    2014-06-01

    Long term outdoor radon measurements were recorded in Ireland using CR-39 track etch detectors. A measurement protocol was designed for this study, which was optimized for the relatively low radon concentrations expected outdoors. This protocol included pre-etching the detectors before exposure to allow radon tracks to be more easily distinguished from background. The average outdoor radon concentration for the Republic of Ireland was found to be 5.6 ± 0.7 Bq m(-3). A statistically significant difference between inland and coastal radon concentrations was evident but no difference between mean radon concentrations on the east coast and those on the west coast was observed.

  18. Low-level birefringence measurement by cyclic-path polarization interferometer.

    PubMed

    Chakraborty, Sonali; Bhattacharya, K

    2016-07-20

    A modified cyclic-path interferometer is employed for complete measurement of spatially varying birefringence. An expanded and collimated laser beam intercepted by a birefringent specimen is incident on a polarization-masked cube beam splitter, resulting in two mutually orthogonal polarization components propagating along clockwise and counterclockwise directions in the interferometer. These two wavefronts are made to interfere for four specific orientations of an analyzer. Suitable combinations of the interferograms result in determination of the direction of birefringence and its magnitude. Experimental results are presented. PMID:27463918

  19. Low Level Gamma Spectroscopy Measurements of Radium and Cesium in Lucerne (Medicago Sativa)

    NASA Astrophysics Data System (ADS)

    Fokapić, S.; Bikit, I.; Mrđa, D.; Vesković, M.; Slivka, J.; Mihaljev, Ž.; Ćupić, Ž.

    2007-04-01

    Nineteen years after Chernobyl nuclear accident, activity concentration of 137Cs still could be detected in food and soil samples in Central and Eastern Europe. In this paper radiation levels of radium and cesium in Lucerne will be presented. It is a perennial plant with a deep root system and it is widely grown throughout the world as forage for cattle. The samples of Lucerne were taken from twelve different locations in Vojvodina in the summer period July-September 2004. The samples were specially dried on the air and after that ground, powdered and mineralized by method of dry burning on the temperature of 450°C. Gamma spectrometry measurements of the ash were performed by means of actively shielded germanium detector with maximal background reduction. For cesium 137Cs 10 mBq/kg order of magnitude detection limits were achieved.

  20. Low Level Gamma Spectroscopy Measurements of Radium and Cesium in Lucerne (Medicago Sativa)

    SciTech Connect

    Fokapic, S.; Bikit, I.; Mrda, D.; Veskovic, M.; Slivka, J.; Mihaljev, Z.; Cupic, Z.

    2007-04-23

    Nineteen years after Chernobyl nuclear accident, activity concentration of 137Cs still could be detected in food and soil samples in Central and Eastern Europe. In this paper radiation levels of radium and cesium in Lucerne will be presented. It is a perennial plant with a deep root system and it is widely grown throughout the world as forage for cattle. The samples of Lucerne were taken from twelve different locations in Vojvodina in the summer period July-September 2004. The samples were specially dried on the air and after that ground, powdered and mineralized by method of dry burning on the temperature of 450 deg. C. Gamma spectrometry measurements of the ash were performed by means of actively shielded germanium detector with maximal background reduction. For cesium 137Cs 10 mBq/kg order of magnitude detection limits were achieved.

  1. Measurements of low-level anthropogenic radionuclides from soils around Maralinga

    NASA Astrophysics Data System (ADS)

    Tims, Stephen G.; Tsifakis, Dimitrios; Srncik, Michaela; Fifield, L. Keith; Hancock, Gary J.; De Cesare, Mario

    2013-12-01

    The isotopes 239Pu and 240Pu are present in surface soils as a result of global fallout from nuclear weapons tests carried out in the 1950's and 1960's. These isotopes constitute artificial tracers of recent soil erosion and sediment movement. In practice the high throughput capabilities and high sensitivity of the AMS technique makes the study of Australia's geographically large areas viable using Pu isotopes. As part of its weapons development program the United Kingdom carried out a series of atmospheric and surface nuclear weapons tests at Maralinga, South Australia in 1956 and 1957. The contribution from the Maralinga tests to the Pu isotopic abundances present in the region around Maralinga is largely unknown. In global fallout, for example, the 240Pu/239Pu ratio is typically in the range 0.17 - 0.19, but the influence of the regional tests could lead to values outside this range. This would impact on the assessment techniques used in the soil and sediment tracer studies. We report recent measurements on soil samples collected from across the Maralinga Test site.

  2. Current measurement apparatus

    DOEpatents

    Umans, Stephen D.

    2008-11-11

    Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

  3. Current measuring system

    DOEpatents

    Dahl, David A.; Appelhans, Anthony D.; Olson, John E.

    1997-01-01

    A current measuring system comprising a current measuring device having a first electrode at ground potential, and a second electrode; a current source having an offset potential of at least three hundred volts, the current source having an output electrode; and a capacitor having a first electrode electrically connected to the output electrode of the current source and having a second electrode electrically connected to the second electrode of the current measuring device.

  4. Current measuring system

    DOEpatents

    Dahl, D.A.; Appelhans, A.D.; Olson, J.E.

    1997-09-09

    A current measuring system is disclosed comprising a current measuring device having a first electrode at ground potential, and a second electrode; a current source having an offset potential of at least three hundred volts, the current source having an output electrode; and a capacitor having a first electrode electrically connected to the output electrode of the current source and having a second electrode electrically connected to the second electrode of the current measuring device. 4 figs.

  5. Quantification of Low-Level Drug Effects Using Real-Time, in vitro Measurement of Oxygen Consumption Rate.

    PubMed

    Neal, Adam; Rountree, Austin M; Philips, Craig W; Kavanagh, Terrance J; Williams, Dominic P; Newham, Peter; Khalil, Gamal; Cook, Daniel L; Sweet, Ian R

    2015-12-01

    There is a general need to detect toxic effects of drugs during preclinical screening. We propose that increased sensitivity of xenobiotics toxicity combined with improved in vitro physiological recapitulation will more accurately assess potentially toxic perturbations of cellular biochemistry that are near in vivo pharmacological exposure levels. Importantly, measurement of such cytopathologies avoids activating mechanisms mediating toxicity at suprapharmacologic levels not relevant to in vivo effects. We present a sensitive method to measure changes in oxygen consumption rate (OCR), a well-established parameter reflecting a potential hazard, in response to exposure to pharmacologic levels of drugs using a flow culture system and state of the art oxygen sensing system. We tested metformin and acetaminophen on rat liver slices to illustrate the method. The features of the method include continuous and very stable measurement of OCR over the course of 48 h in liver slices in a continuous flow chamber with the ability to resolve changes as small as 0.3%/h. Kinetic modeling of metformin inhibition of OCR over a wide range of concentrations revealed both a slow and fast mechanism, where the fast mechanism activated only at concentrations above 0.6 mM. For both drugs, small amounts of inhibition were reversible, but higher decrements were irreversible. Overall the study highlights the advantages of measuring low-level toxicity so as to avoid the common extrapolations made about drug toxicity based on effects of drugs tested at suprapharmacologic levels.

  6. Quantification of Low-Level Drug Effects Using Real-Time, in vitro Measurement of Oxygen Consumption Rate.

    PubMed

    Neal, Adam; Rountree, Austin M; Philips, Craig W; Kavanagh, Terrance J; Williams, Dominic P; Newham, Peter; Khalil, Gamal; Cook, Daniel L; Sweet, Ian R

    2015-12-01

    There is a general need to detect toxic effects of drugs during preclinical screening. We propose that increased sensitivity of xenobiotics toxicity combined with improved in vitro physiological recapitulation will more accurately assess potentially toxic perturbations of cellular biochemistry that are near in vivo pharmacological exposure levels. Importantly, measurement of such cytopathologies avoids activating mechanisms mediating toxicity at suprapharmacologic levels not relevant to in vivo effects. We present a sensitive method to measure changes in oxygen consumption rate (OCR), a well-established parameter reflecting a potential hazard, in response to exposure to pharmacologic levels of drugs using a flow culture system and state of the art oxygen sensing system. We tested metformin and acetaminophen on rat liver slices to illustrate the method. The features of the method include continuous and very stable measurement of OCR over the course of 48 h in liver slices in a continuous flow chamber with the ability to resolve changes as small as 0.3%/h. Kinetic modeling of metformin inhibition of OCR over a wide range of concentrations revealed both a slow and fast mechanism, where the fast mechanism activated only at concentrations above 0.6 mM. For both drugs, small amounts of inhibition were reversible, but higher decrements were irreversible. Overall the study highlights the advantages of measuring low-level toxicity so as to avoid the common extrapolations made about drug toxicity based on effects of drugs tested at suprapharmacologic levels. PMID:26396153

  7. CIRCUITS FOR CURRENT MEASUREMENTS

    DOEpatents

    Cox, R.J.

    1958-11-01

    Circuits are presented for measurement of a logarithmic scale of current flowing in a high impedance. In one form of the invention the disclosed circuit is in combination with an ionization chamber to measure lonization current. The particular circuit arrangement lncludes a vacuum tube having at least one grid, an ionization chamber connected in series with a high voltage source and the grid of the vacuum tube, and a d-c amplifier feedback circuit. As the ionization chamber current passes between the grid and cathode of the tube, the feedback circuit acts to stabilize the anode current, and the feedback voltage is a measure of the logaritbm of the ionization current.

  8. Wavelet analysis on vibration modal frequency measurement at a low level of strain of the turbine blade using FBG sensors

    NASA Astrophysics Data System (ADS)

    Huang, Xue-feng; Liu, Yan; Luo, Dan; Wang, Guan-qing; Ding, Ning; Xu, Jiang-rong; Huang, Xue-jing

    2010-01-01

    Vibration modal frequency measurement of a turbine blade was investigated by using fiber Bragg grating (FBG) sensors for their adaptation for a low level of strain at high frequency. However, the signal-to-noise ratio was so low that it was very difficult to identify dominant modal frequency from a raw signal acquired. An attempt was made to solve this problem. First, a bi-linear transform elliptic filter with pass-band and stop-band was proposed to remove electromagnetic interference noise. Second, discrete stationary wavelet transform with a soft threshold was utilized to de-noise the high-frequency part. Third, wavelet packet transform was exploited to decompose the time signal and to obtain the power spectrum and identification of dominant modal frequency. Experimental and analytic results demonstrated that four stages of dominant modal frequencies of the turbine blade without any constraint condition (free vibration) and three stages of dominant modal frequencies with a constraint condition (A-type vibration) were obtained, respectively. To testify to the validity of analytic results, a professional computer random signal and vibration analysis system (CRAS) was used to measure modal frequency. The results illustrated that modal frequencies obtained by the CRAS platform yielded close agreement with those based on FBG sensors. Obviously, wavelet analysis is successfully employed to decode vibration modal frequency from a raw signal of FBG sensors.

  9. Efficacy of low level electric current (A-C) for controlling quagga mussles in the Welland Canal

    SciTech Connect

    Fears, C.; Mackie, G.L.

    1995-06-01

    The efficacy of systems (for which patents are pending) which use low-voltage A-C currents for preventing settlement and attachment by zebra mussels were tested with steel rods and plates placed near the intake of a pulp and paper plant in the Welland Canal at Thorold, Ontario. Six racks made of 16 ft. (4.9 m), 2x4s (5.1 x 10.2 cm) were placed into the Welland Canal on August 5, 1994. One rack had 1/8th in (3.2 mm) diam x 12 in (30.5 cm) long steel rods, each separated by 2 in (5.1 cm) attached to pressure treated wood and concrete blocks and an A-C current of 16 v (or 8 v/in); rack 2 had steel rods of the same configuration but 12 v (or 6 v/in) was applied; rack 3 was identical to these but no current was applied and was used as a rod control. The remaining three racks had steel plates, each plate being 3 in (7.6 cm) wide X 24 in (61 cm) long X 1/4 in (6.4 mm) thick and separated by 2 in (5.1 cm); one had 12 v applied (or 6 v/in), another had 16 v applied (or 8 v/in), and the third had no current and was used as a plate control. The racks were placed on the upstream and downstream side of the intake at a depth of about 7 ft (2.1 m) where the mussels populations were heaviest (as determined by SCUBA diving). All mussels were quagga mussels (Dreissena bugensis). The racks were pulled in mid November after settlement was complete and the results showed: (1) complete prevention of settlement of both new recruits and translocators at 8 volts/in with steel rods on both wood and concrete surfaces and with steel plate trash bars; (2) partial prevention of settlement at 6 volts/in with steel rods on both wood and concrete surfaces and steel plates; and (3) that, at current kilowatt hr rates, total efficacy at 8 volts/in would cost approximately $10.80/day/1000 sq ft using rods to protect concrete walls and about $16.32/day/1000 sq ft to protect 3 in wide x 1/4 in thick trash bars. These costs can be reduced even further with pulse dosed AC currents.

  10. Whole Ecosystem Low-level 14C Pulse Labeling and CO2 Flux Measurements in a Boreal Forest

    NASA Astrophysics Data System (ADS)

    Carbone, M.; Trumbore, S.; Czimczik, C.; McDuffee, K.; McMillan, A.

    2004-12-01

    We developed a large volume, low level, 14C pulse-chase, field labeling method to determine the timing and contribution of recent photosynthetic products to total ecosystem respiration in a poorly drained black spruce forest stand in Manitoba, Canada. The site is part of a chronosequence of black spruce stands located in the BOREAS Northern Study Area (55N, 98W), and time since fire is 40 years. The radiocarbon addition was designed to produce a 14C signature of ~1500 times Modern for CO2 at ambient levels inside the ~37,000 L volume light chamber. At this level of labeling, the radioactivity in our 14C source (acidified sodium bicarbonate solution with specific activity of ~30 nCi/g) and in the chamber were well below levels that are regulated. We labeled two chambers in August 2004. The vegetation inside the first (37,000 L) chamber included black spruce trees (ranging from seedlings to 4 m tall) with feather moss and shrub understory. A second 14CO2 label was applied in a smaller chamber (500 L) containing only feather mosses. Both chambers were constructed from polyethylene plastic that allowed for 70 percent transmission of PAR. For seven days following the label, we measured the quantity and 14C content of soil respiration with small (10 L) dark chambers, above-ground respiration with branch bags, and total ecosystem respiration with a dark chamber. Live root and moss 14C content were measured by field incubations. Additionally, soil gas 14C content at two depths within the moss/organic layer was measured. Radiocarbon measurements are made using Accelerator Mass Spectrometry, which allows us to easily distinguish the presence of the label in small amounts (mg) of material. We will report the radiocarbon (delta 14C) signature of individual respiration sources. Preliminary results show that we can use these isotopic signatures to follow the labeled contribution of respiration from individual sources (moss, root/root exudates, and needle) to total ecosystem

  11. WIPP WAC Equivalence Support Measurements for Low-Level Sludge Waste at Los Alamos National Laboratory - 12242

    SciTech Connect

    Gruetzmacher, Kathleen M.; Bustos, Roland M.; Ferran, Scott G.; Gallegos, Lucas E.; Lucero, Randy P.

    2012-07-01

    Los Alamos National Laboratory (LANL) uses the Nevada National Security Site (NNSS) as an off-site disposal facility for low-level waste (LLW), including sludge waste. NNSS has issued a position paper that indicates that systems that are not certified by the Carlsbad Field Office (CBFO) for Waste Isolation Pilot Plant (WIPP) disposal of Transuranic (TRU) waste must demonstrate equivalent practices to the CBFO certified systems in order to assign activity concentration values to assayed items without adding in the Total Measurement Uncertainty (TMU) when certifying waste for NNSS disposal. Efforts have been made to meet NNSS requirements to accept sludge waste for disposal at their facility. The LANL LLW Characterization Team uses portable high purity germanium (HPGe) detector systems for the nondestructive assay (NDA) of both debris and sludge LLW. A number of performance studies have been conducted historically by LANL to support the efficacy and quality of assay results generated by the LANL HPGe systems, and, while these detector systems are supported by these performance studies and used with LANL approved procedures and processes, they are not certified by CBFO for TRU waste disposal. Beginning in 2009, the LANL LLW Characterization Team undertook additional NDA measurements of both debris and sludge simulated waste containers to supplement existing studies and procedures to demonstrate full compliance with the NNSS position paper. Where possible, Performance Demonstration Project (PDP) drums were used for the waste matrix and PDP sources were used for the radioactive sources. Sludge drums are an example of a matrix with a uniform distribution of contaminants. When attempting to perform a gamma assay of a sludge drum, it is very important to adequately simulate this uniform distribution of radionuclides in order to accurately model the assay results. This was accomplished by using a spiral radial source tube placement in a sludge drum rather than the standard

  12. Low-Level Violence in Schools: Is There an Association between School Safety Measures and Peer Victimization?

    ERIC Educational Resources Information Center

    Blosnich, John; Bossarte, Robert

    2011-01-01

    Background: Low-level violent behavior, particularly school bullying, remains a critical public health issue that has been associated with negative mental and physical health outcomes. School-based prevention programs, while a valuable line of defense to stave off bullying, have shown inconsistent results in terms of decreasing bullying. This…

  13. Musical emotions: predicting second-by-second subjective feelings of emotion from low-level psychoacoustic features and physiological measurements.

    PubMed

    Coutinho, Eduardo; Cangelosi, Angelo

    2011-08-01

    We sustain that the structure of affect elicited by music is largely dependent on dynamic temporal patterns in low-level music structural parameters. In support of this claim, we have previously provided evidence that spatiotemporal dynamics in psychoacoustic features resonate with two psychological dimensions of affect underlying judgments of subjective feelings: arousal and valence. In this article we extend our previous investigations in two aspects. First, we focus on the emotions experienced rather than perceived while listening to music. Second, we evaluate the extent to which peripheral feedback in music can account for the predicted emotional responses, that is, the role of physiological arousal in determining the intensity and valence of musical emotions. Akin to our previous findings, we will show that a significant part of the listeners' reported emotions can be predicted from a set of six psychoacoustic features--loudness, pitch level, pitch contour, tempo, texture, and sharpness. Furthermore, the accuracy of those predictions is improved with the inclusion of physiological cues--skin conductance and heart rate. The interdisciplinary work presented here provides a new methodology to the field of music and emotion research based on the combination of computational and experimental work, which aid the analysis of the emotional responses to music, while offering a platform for the abstract representation of those complex relationships. Future developments may aid specific areas, such as, psychology and music therapy, by providing coherent descriptions of the emotional effects of specific music stimuli.

  14. Testing and Performance Validation of a Shielded Waste Segregation and Clearance Monitor Designed for the Measurement of Low Level Waste-13043

    SciTech Connect

    Mason, John A.; Burke, Kevin J.; Towner, Antony C.N.; Beaven, Graham; Spence, Robert

    2013-07-01

    This paper describes the development, testing and validation of a shielded waste segregation and clearance monitor designed for the measurement of low-density low-level waste (LLW). The monitor is made of a measurement chamber surrounded by detectors and a shielded outer frame. The shielded chamber consists of a steel frame, which contains typically 1.5 inches (3.81 cm) of lead and 0.5 inches (1.27 cm) of steel shielding. Inside the shielding are plastic scintillator panels, which serve as gross gamma ray detectors. The detector panels, with embedded photomultipliers, completely surround the internal measurement chamber on all 6 sides. Care has been taken to distribute the plastic scintillator detectors in order to optimise both the efficiency for gamma ray detection and at the same time achieve a volumetric sensitivity, which is as uniform as possible. A common high voltage power supply provides the bias voltage for each of the six photomultipliers. The voltage signals arising from the detectors and photomultipliers are amplified by six sensitive amplifiers. Each amplifier incorporates a single channel analyser with both upper and lower thresholds and the digitised counts from each detector are recorded on six scalars. Operation of the device is by means of a microprocessor from which the scalars are controlled. An internal load cell linked to the microprocessor determines the weight of the waste object, and this information is used to calculate the specific activity of the waste. The monitor makes background measurements when the shielded door is closed and a sample, usually a bag of low-density waste, is not present in the measurement chamber. Measurements of the minimum detectable activity (MDA) of an earlier large volume prototype instrument are reported as part of the development of the Waste Segregation and Clearance Monitor (WSCM) described in the paper. For the optimised WSCM a detection efficiency of greater than 32% was measured using a small Cs-137

  15. Packaged low-level waste verification system

    SciTech Connect

    Tuite, K.; Winberg, M.R.; McIsaac, C.V.

    1995-12-31

    The Department of Energy through the National Low-Level Waste Management Program and WMG Inc. have entered into a joint development effort to design, build, and demonstrate the Packaged Low-Level Waste Verification System. Currently, states and low-level radioactive waste disposal site operators have no method to independently verify the radionuclide content of packaged low-level waste that arrives at disposal sites for disposition. At this time, the disposal site relies on the low-level waste generator shipping manifests and accompanying records to ensure that low-level waste received meets the site`s waste acceptance criteria. The subject invention provides the equipment, software, and methods to enable the independent verification of low-level waste shipping records to ensure that the site`s waste acceptance criteria are being met. The objective of the prototype system is to demonstrate a mobile system capable of independently verifying the content of packaged low-level waste.

  16. Low level measurements of atmospheric DMS, H2S, and SO2 for GTE/CITE-3

    NASA Technical Reports Server (NTRS)

    Saltzman, Eric; Cooper, David

    1991-01-01

    This project involved the measurement of atmospheric dimethylsulfide (DMS) and hydrogen sulfide (H2S) as part of the GTE/CITE-3 instrument intercomparison program. The two instruments were adapted for use on the NASA Electra aircraft and participated in all phases of the mission. This included ground-based measurements of NIST-provided standard gases and a series of airborne missions over the Western Atlantic Ocean. Analytical techniques used are described and the results are summarized.

  17. Detection of low level gaseous releases and dose evaluation from continuous gamma dose measurements using a wavelet transformation technique.

    PubMed

    Paul, Sabyasachi; Rao, D D; Sarkar, P K

    2012-11-01

    Measurement of environmental dose in the vicinity of a nuclear power plant site (Tarapur, India) is carried out continuously for the years 2007-2010 and attempts have been made to quantify the additional contributions from nuclear power plants over natural background by segregating the background fluctuations from the events due to plume passage using a non-decimated wavelet approach. A conservative estimate obtained using wavelet based analysis has shown a maximum annual dose of 38 μSv in a year at 1.6 km and 4.8 μSv at 10 km from the installation. The detected events within a year are in good agreement with the month wise wind-rose profile indicating reliability of the algorithm for proper detection of an event from the continuous dose rate measurements. The results were validated with the dispersion model dose predictions using the source term from routine monitoring data and meteorological parameters.

  18. Advanced quadrupole ion trap instrumentation for low level vehicle emissions measurements. CRADA final report for number ORNL93-0238

    SciTech Connect

    McLuckey, S.A.; Buchanan, M.V.; Asano, K.G.; Hart, K.J.; Goeringer, D.E.; Dearth, M.A.

    1997-09-01

    Quadrupole ion trap mass spectrometry has been evaluated for its potential use in vehicle emissions measurements in vehicle test facilities as an analyzer for the top 15 compounds contributing to smog generation. A variety of ionization methods were explored including ion trap in situ chemical ionization, atmospheric sampling glow discharge ionization, and nitric oxide chemical ionization in a glow discharge ionization source coupled with anion trap mass spectrometer. Emphasis was placed on the determination of hydrocarbons and oxygenated hydrocarbons at parts per million to parts per billion levels. Ion trap in situ water chemical ionization and atmospheric sampling glow discharge ionization were both shown to be amenable to the analysis of arenes, alcohols, aldehydes and, to some degree, alkenes. Atmospheric sampling glow discharge also generated molecular ions of methyl-t-butyl ether (MTBE). Neither of these ionization methods, however, were found to generate diagnostic ions for the alkanes. Nitric oxide chemical ionization, on the other hand, was found to yield diagnostic ions for alkanes, alkenes, arenes, alcohols, aldehydes, and MTBE. The ability to measure a variety of hydrocarbons present at roughly 15 parts per billion at measurement rates of 3 Hz was demonstrated. These results have demonstrated that the ion trap has an excellent combination of sensitivity, specificity, speed, and flexibility with respect to the technical requirements of the top 15 analyzer.

  19. In vitro measurements of oxygen consumption rates in hTERT-RPE cells exposed to low levels of red light

    NASA Astrophysics Data System (ADS)

    Wigle, Jeffrey C.; Castellanos, Cherry C.

    2016-03-01

    Exposure to 2.88 J/cm2 of red light induces an adaptive response against a lethal pulse of 2.0 μm laser radiation in hTERT-RPE cells in vitro, but not in a knockdown mutant for vascular endothelial growth factor c (VEGF-C). The generally accepted initiation sequence for photobiomodulation is that absorption of red light by cytochome c oxidase (CCOX) of the electron transport chain increases the binding affinity of CCOX for O2 vs. nitric oxide (NO). This results in displacement of NO by O2 in the active site of CCOX, thereby increasing cellular respiration and intracellular ATP. We've previously reported that red-light exposure induces a small, but consistently reproducible, increase in NO levels in these cells. But the relative importance of NO and oxidative phosphorylation is unclear because little is known about the relative contributions of NO and ATP to the response. However, if NO dissociation from CCOX actually increases oxidative phosphorylation, one should see a corresponding increase in oxygen consumption. A Seahorse Extracellular Flux Analyzer was used to measure oxygen consumption rates (OCR) in normal and mutant cells as a proxy for oxidative phosphorylation. Both basal respiration and maximum respiration rates in normal cells are significantly higher than in the mutant. The normal cells have a significant amount of "excess capacity," whereas the VEGF-C(KD) have little or none. The OCR in exposed normal cells is lower than in unexposed cells when measured immediately after exposure. The exposures used for these experiments had no effect on the OCR in mutant cells.

  20. [A method for measuring urinary concentrations of benzene. Its use in monitoring of subjects exposed to low levels].

    PubMed

    Fiorentino, M L; Ghittori, S; Pezzagno, G

    1990-01-01

    Benzene is a widely diffuse solvent (atmosphere, cigarette smoke, some foods); in the industrial environment benzene is currently present at concentrations of ppm. A valid method of biological monitoring that is easy to perform is needed for assessing occupational and non-occupational exposures. A new method has been developed to evaluate low concentrations of benzene in urine samples by means of a "dynamic" headspace (50 ml of urine in a 120 ml vial). The urine is saturated with anhydrous Na2SO4 in order to support the entrance of benzene in the air over the urine. The solvent is stripped from the urine surface and concentrated on an adsorbent substrate (Carbotrap 100 tube) by means of a suction pump (150 ml/min). A simultaneous intake of filtered air through a charcoal tube allows wash-up of the headspace. Benzene is thermically desorbed and injected in a column (Thermal tube desorber-Supelco; 370 degrees C thermal flash; borosilicate capillary glass column SPB-1 60 m length, 0.75 mm I.D., 1 micron film thickness; G.C. Dani 8580-FID). The detection limit of the method is about 50 ng/l and the variation coefficient is 4.7%. The method was checked on urine samples of 5 non-smokers and 5 smokers: mean values of 135 and 944 ng/l respectively were obtained. A further analysis on urine samples of 60 smokers revealed a significant relationship (p less than 0.001) between urinary benzene concentrations and C0 alveolar concentrations (r = 0.626). A close relationship between benzene exposure levels and urinary concentrations was found in a group of workers exposed to low environmental benzene concentrations (mean value 1200 micrograms/m3) (r = 0.763).

  1. Nitric oxide measurements in hTERT-RPE cells and subcellular fractions exposed to low levels of red light

    NASA Astrophysics Data System (ADS)

    Wigle, Jeffrey C.; Castellanos, Cherry C.; Denton, Michael L.; Holwitt, Eric A.

    2014-02-01

    Cells in a tissue culture model for laser eye injury exhibit increased resistance to a lethal pulse of 2.0-μm laser radiation if the cells are first exposed to 2.88 J/cm2 of red light 24 hr prior to the lethal laser exposure. Changes in expression of various genes associated with apoptosis have been observed, but the biochemical link between light absorption and gene expression remains unknown. Cytochome c oxidase (CCOX), in the electron transport chain, is the currentlyhypothesized absorber. Absorption of the red light by CCOX is thought to facilitate displacement of nitric oxide (NO) by O2 in the active site, increasing cellular respiration and intracellular ATP. However, NO is also an important regulator and mediator of numerous physiological processes in a variety of cell and tissue types that is synthesized from l-arginine by NO synthases. In an effort to determine the relative NO contributions from these competing pathways, we measured NO levels in whole cells and subcellular fractions, with and without exposure to red light, using DAF-FM, a fluorescent dye that stoichiometrically reacts with NO. Red light induced a small, but consistently reproducible, increase in fluorescence intensity in whole cells and some subcellular fractions. Whole cells exhibited the highest overall fluorescence intensity followed by (in order) cytosolic proteins, microsomes, then nuclei and mitochondria.

  2. Low-Level, Measured Response of Los Alamos National Laboratories TA 16 - Building 411 and TA 8 - Building 23 to Direct Flash Attachment of Lightning

    SciTech Connect

    Dinallo, Michael A.; Holmes, Parris; Merewether, Kimball O.; Morris, Marvin E.

    1999-02-01

    On September 24, 25, 28, and 29, 1998 and on October 19 and 23, 1998, transfer impedance measurements were made on Los Alamos National Laboratories TA 16 - Building 411 and TA 8-- Building 23 to characterize their interior open-circuit voltage response to a direct lightning flash attachment to the structures. The theory, history, measurement methods and equipment, and specific measured results are detailed. The measured results demonstrate that if the remaining metallic penetrations are bonded, then the rebar of the two structures is sufficiently well connected to form a Faraday cage that reduces the maximum open-circuit voltage inside the structure to a sufficiently low level that the required standoff distance to prevent arcing to explosive assemblies is 6.8 inches for TA 16 - Building 411 and is 11.5 inches for TA 8 - Building 23.

  3. Low level TOC measurement method

    DOEpatents

    Ekechukwu, Amy A.

    2001-01-01

    A method for the determination of total organic carbon in an aqueous sample by trapping the organic matter on a sorbent which is carbon free and analyzing the sorbent by combustion and determination of total CO.sub.2 by IR.

  4. Measuring the dynamics of cyclic adenosine monophosphate level in living cells induced by low-level laser irradiation using bioluminescence resonance energy transfer

    NASA Astrophysics Data System (ADS)

    Huang, Yimei; Zheng, Liqin; Yang, Hongqin; Chen, Jiangxu; Wang, Yuhua; Li, Hui; Xie, Shusen; Zeng, Haishan

    2015-05-01

    Several studies demonstrated that the cyclic adenosine monophosphate (cAMP), an important second messenger, is involved in the mechanism of low-level laser irradiation (LLLI) treatment. However, most of these studies obtained the cAMP level in cell culture extracts or supernatant. In this study, the cAMP level in living cells was measured with bioluminescence resonance energy transfer (BRET). The effect of LLLI on cAMP level in living cells with adenosine receptors blocked was explored to identify the role of adenosine receptors in LLLI. The results showed that LLLI increased the cAMP level. Moreover, the rise of cAMP level was light dose dependent but wavelength independent for 658-, 785-, and 830-nm laser light. The results also exhibited that the adenosine receptors, a class of G protein-coupled receptor (GPCR), modulated the increase of cAMP level induced by LLLI. The cAMP level increased more significantly when the A3 adenosine receptors (A3R) were blocked by A3R antagonist compared with A1 adenosine receptor or A2a adenosine receptor blocked in HEK293T cells after LLLI, which was in good agreement with the adenosine receptors' expressions. All these results suggested that measuring the cAMP level with BRET could be a useful technique to study the role of GPCRs in living cells under LLLI.

  5. Poor physical function in elderly women in low-level aged care is related to muscle strength rather than to measures of sarcopenia

    PubMed Central

    Woods, Julie L; Iuliano-Burns, Sandra; King, Susannah J; Strauss, Boyd J; Walker, Karen Z

    2011-01-01

    Purpose: To determine the prevalence of sarcopenia and investigate relationships among body composition, muscle strength, and physical function in elderly women in low-level aged care. Subjects and methods: Sixty-three ambulatory women (mean age 86 years) participated in this cross-sectional study where body composition was determined by dual energy X-ray absorptiometry (DXA); ankle, knee, and hip strength by the Nicholas Manual Muscle Tester; and physical function by ‘timed up and go’ (TUG) and walking speed (WS) over 6 meters. Body composition data from a female reference group (n = 62, mean age 29 years) provided cut-off values for defining sarcopenia. Results: Elderly women had higher body mass index (P < 0.001), lower lean mass (P < 0.001), and higher fat mass (P < 0.01) than the young reference group. Only a small proportion (3.2%) had absolute sarcopenia (defined by appendicular skeletal muscle mass/height squared) whereas 37% had relative sarcopenia class II (defined by percentage skeletal muscle mass). Scores for TUG and WS indicated relatively poor physical function, yet these measures were not associated with muscle mass or indices of sarcopenia. In multivariate analysis, only hip abductor strength predicted both TUG and WS (both P = 0.01). Conclusion: Hip strength is a more important indicator of physical functioning than lean mass. Measurement of hip strength may therefore be a useful screening tool to detect those at risk of functional decline and requirement for additional care. Further longitudinal studies with a range of other strength measures are warranted. PMID:21472094

  6. METHOD OF PEAK CURRENT MEASUREMENT

    DOEpatents

    Baker, G.E.

    1959-01-20

    The measurement and recording of peak electrical currents are described, and a method for utilizing the magnetic field of the current to erase a portion of an alternating constant frequency and amplitude signal from a magnetic mediums such as a magnetic tapes is presented. A portion of the flux from the current carrying conductor is concentrated into a magnetic path of defined area on the tape. After the current has been recorded, the tape is played back. The amplitude of the signal from the portion of the tape immediately adjacent the defined flux area and the amplitude of the signal from the portion of the tape within the area are compared with the amplitude of the signal from an unerased portion of the tape to determine the percentage of signal erasure, and thereby obtain the peak value of currents flowing in the conductor.

  7. The Development of Low-Level Measurement Capabilities for Total and Isotopic Uranium in Environmental Samples at Brazilian and Argentine Laboratories by ABACC

    SciTech Connect

    Guidicini, Olga M.; Olsen, Khris B.; Hembree, Doyle M.; Carter, Joel A.; Whitaker, Michael; Hayes, Susan M.

    2005-07-01

    In June 1998, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC), with assistance from the U.S. Department of Energy (DOE), began a program to assess environmental sampling and analysis capabilities at laboratories in Argentina and Brazil. The program began with staff training conducted in South America and the United States by Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL). Both laboratories are participating members of DOE’s Network of Analytical Laboratories (NWAL) that support IAEA’s environmental sampling program. During the initial planning meeting, representatives from ABACC and all the participating analytical laboratories supporting ABACC were briefed on how the first exercise would be managed and on key aspects necessary to analyze low-level environmental samples for uranium. Subsequent to this training, a laboratory evaluation exercise (Exercise 1) was conducted using standard swipe samples prepared for this exercise by the International Atomic Energy Agency (IAEA). The results of Exercise 1 determined that sample contamination was a major factor in the analysis, and a thorough review of laboratory procedures was required to reduce the level of contamination to acceptable levels. Following modification of sample preparation procedures, the laboratories performed Exercise 2, an analysis of a National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1547, Peach Leaves. The results of Exercise 2 demonstrated that several laboratories were capable of accurately determining the total uranium and uranium isotopic distribution in the peach leaves. To build on these successes, Exercise 3 was performed using a series of standard swipe samples prepared by the IAEA and distributed to laboratories supporting ABACC and to PNNL and ORNL. The results of Exercise 3 demonstrate that ABACC now has support laboratories in both Argentina and Brazil, which are capable

  8. Teaching the Low Level Achiever.

    ERIC Educational Resources Information Center

    Salomone, Ronald E., Ed.

    1986-01-01

    Intended for teachers of the English language arts, the articles in this issue offer suggestions and techniques for teaching the low level achiever. Titles and authors of the articles are as follows: (1) "A Point to Ponder" (Rachel Martin); (2) "Tracking: A Self-Fulfilling Prophecy of Failure for the Low Level Achiever" (James Christopher Davis);…

  9. Low-level measuring techniques for neutrons: High accuracy neutron source strength determination and fluence rate measurement at an underground laboratory

    SciTech Connect

    Zimbal, Andreas; Reginatto, Marcel; Schuhmacher, Helmut; Wiegel, Burkhard; Degering, Detlev; Zuber, Kai

    2013-08-08

    We report on measuring techniques for neutrons that have been developed at the Physikalisch-Technische Bundesanstalt (PTB), the German National Metrology Institute. PTB has characterized radioactive sources used in the BOREXINO and XENON100 experiments. For the BOREXINO experiment, a {sup 228}Th gamma radiation source was required which would not emit more than 10 neutrons per second. The determination of the neutron emission rate of this specially designed {sup 228}Th source was challenging due to the low neutron emission rate and because the ratio of neutron to gamma radiation was expected to be extremely low, of the order of 10{sup −6}. For the XENON100 detector, PTB carried out a high accuracy measurement of the neutron emission rate of an AmBe source. PTB has also done measurements in underground laboratories. A two month measurement campaign with a set of {sup 3}He-filled proportional counters was carried out in PTB's former UDO underground laboratory at the Asse salt mine. The aim of the campaign was to determine the intrinsic background of detectors, which is needed for the analysis of data taken in lowintensity neutron fields. At a later time, PTB did a preliminary measurement of the neutron fluence rate at the underground laboratory Felsenkeller operated by VKTA. By taking into account data from UDO, Felsenkeller, and detector calibrations made at the PTB facility, it was possible to estimate the neutron fluence rate at the Felsenkeller underground laboratory.

  10. Packaged low-level waste verification system

    SciTech Connect

    Tuite, K.T.; Winberg, M.; Flores, A.Y.; Killian, E.W.; McIsaac, C.V.

    1996-08-01

    Currently, states and low-level radioactive waste (LLW) disposal site operators have no method of independently verifying the radionuclide content of packaged LLW that arrive at disposal sites for disposal. At this time, disposal sites rely on LLW generator shipping manifests and accompanying records to insure that LLW received meets the waste acceptance criteria. An independent verification system would provide a method of checking generator LLW characterization methods and help ensure that LLW disposed of at disposal facilities meets requirements. The Mobile Low-Level Waste Verification System (MLLWVS) provides the equipment, software, and methods to enable the independent verification of LLW shipping records to insure that disposal site waste acceptance criteria are being met. The MLLWVS system was developed under a cost share subcontract between WMG, Inc., and Lockheed Martin Idaho Technologies through the Department of Energy`s National Low-Level Waste Management Program at the Idaho National Engineering Laboratory (INEL).

  11. Disposal of low-level radioactive wastes.

    PubMed

    Hendee, W R

    1986-07-01

    The generation of low-level radioactive waste is a natural consequence of the societal uses of radioactive materials. These uses include the application of radioactive materials to the diagnosis and treatment of human disease and to research into the causes of human disease and their prevention. Currently, low level radioactive wastes are disposed of in one of three shallow land-burial disposal sites located in Washington, Nevada, and South Carolina. With the passage in December 1980 of Public Law 96-573, "The Low-Level Radioactive Waste Policy Act," the disposal of low-level wastes generated in each state was identified as a responsibility of the state. To fulfill this responsibility, states were encouraged to form interstate compacts for radioactive waste disposal. At the present time, only 37 states have entered into compact agreements, in spite of the clause in Public Law 96-573 that established January 1, 1986, as a target date for implementation of state responsibility for radioactive wastes. Recent action by Congress has resulted in postponement of the implementation date to January 1, 1993.

  12. Low level moisture from VAS

    NASA Technical Reports Server (NTRS)

    Hayden, C. M.

    1980-01-01

    Previous research and current opinion are too pessimistic concerning the capability of defining moisture fields from satellite measurements. The TIROS-N sounder is a close analogue to what will fly on GEOS-D and can be used to investigate the probable capability of VAS. Basically, there are three frequencies applied to sensing moisture in the troposphere. The ability of these three measurements to define the moisture pattern is assessed. It is certainly true that one cannot achieve the detail available with a radiosonde hygristor. Sharp discontinuities cannot be sensed by a passive sounder, especially since the measurement tends to "saturate" with the first moisture layer encountered. However, the satellite measurements demonstrate a high degree of skill in defining the horizontal gradient. Moisture "tongues" and "dry lines" are readily delineated with some, perhaps two layers, of vertical definition. These attributes allow both the calculation of important advective quantities as well as (in concert with the temperature sounding) a gross definition of the vertical stability. The skill is demonstrably commensurate with subsynoptic forecast models and perhaps even to regional scale models.

  13. Eddy current thickness measurement apparatus

    DOEpatents

    Rosen, Gary J.; Sinclair, Frank; Soskov, Alexander; Buff, James S.

    2015-06-16

    A sheet of a material is disposed in a melt of the material. The sheet is formed using a cooling plate in one instance. An exciting coil and sensing coil are positioned downstream of the cooling plate. The exciting coil and sensing coil use eddy currents to determine a thickness of the solid sheet on top of the melt.

  14. Twelfth annual US DOE low-level waste management conference

    SciTech Connect

    Not Available

    1990-01-01

    The papers in this document comprise the proceedings of the Department of Energy's Twelfth Annual Low-Level Radioactive Waste Management Conference, which was held in Chicago, Illinois, on August 28 and 29, 1990. General subjects addressed during the conference included: mixed waste, low-level radioactive waste tracking and transportation, public involvement, performance assessment, waste stabilization, financial assurance, waste minimization, licensing and environmental documentation, below-regulatory-concern waste, low-level radioactive waste temporary storage, current challenges, and challenges beyond 1990.

  15. Ogoya underground laboratory for the measurement of extremely low levels of environmental radioactivity: review of recent projects carried out at OUL.

    PubMed

    Komura, Kazuhisa; Hamajima, Yasunori

    2004-01-01

    Recent topical measurements performed in the Ogoya Underground Laboratory are briefly summarized. The paper deals mainly with the following topics: measurements of variations of airborne 222Rn, 210Pb, 210Po and 7Be with high temporal resolution; the depth profile of 137Cs in Pacific water collected in 1957; cosmic-ray-induced 22Na in surface air, rain, river and lake waters; 152Eu in granite exposed to the Atomic Bomb in Hiroshima in 1945; and depleted uranium used in the Iraq War 2003.

  16. Apparatus for measuring high frequency currents

    NASA Technical Reports Server (NTRS)

    Hagmann, Mark J. (Inventor); Sutton, John F. (Inventor)

    2003-01-01

    An apparatus for measuring high frequency currents includes a non-ferrous core current probe that is coupled to a wide-band transimpedance amplifier. The current probe has a secondary winding with a winding resistance that is substantially smaller than the reactance of the winding. The sensitivity of the current probe is substantially flat over a wide band of frequencies. The apparatus is particularly useful for measuring exposure of humans to radio frequency currents.

  17. Enhanced techniques for the measurement of ultra-low level (pg and fg) actinide analysis by ICP-MS for forensic and geologic applications

    NASA Astrophysics Data System (ADS)

    Pollington, A. D.; Kinman, W.; Hanson, S. K.

    2014-12-01

    Recent advances in mass spectrometry have led to an improved ability to measure high precision isotope ratios at increasingly low analyte concentrations. Combining techniques for enhanced ionization with better counting of small ion beams, we routinely measure isotope ratios on 100's of pg uranium samples and ≤10 pg plutonium samples with relative standard deviations of 1‰ on major isotope ratios and 10‰ on minor ratios achievable. With slightly larger samples (≤1 ng total U), these precisions can be as low as 0.01‰ (10 ppm) and 1‰ respectively. These techniques can be applied to both nuclear forensics questions where only a small amount of sample is available, as well as geologic questions such as U-Pb or U-Th disequilibrium geochronology from either single small crystals, or microsampled domains from within a heterogeneous sample. The analytical setup is a Cetac Aridus II desolvating nebulizer interfaced with a ThermoScientific Neptune Plus equipped with a jet-type sample cone and x-type skimmer cone. The combination of the desolvating nebulizer with the enhanced cone setup leads to an increase in sensitivity on the order of 10x that of a standard glass spray chamber (~1000V/ppm U). The Neptune Plus is equipped with 9 Faraday cups and 5 electron multipliers (two behind RPQ energy filters for improved abundance sensitivtiy). This allows for the simultaneous collection of all isotopes of either U or Pu with a combination of Faraday cups (e.g., 235U and 238U) and electron multipliers (e.g., 234U and 236U) with other configurations also available (e.g., 235U and 238U can instead be measured on electron multipliers in small samples). As sample sizes get small, the contributions from environmental blanks, as well as interfering species, become increasing concerns. In this study, we will present data on efforts to minimize the contribution of environmental U using scaled down chemical procedures as well as the effect of polyatomic species on the precision

  18. Seventh annual DOE LLWMP participants' information meeting. DOE Low-Level Waste Management Program. Abstracts

    SciTech Connect

    Not Available

    1985-08-01

    The following sessions were held: International Low-Level Waste Management Activities; Low-Level Waste Disposal; Characteristics and Treatment of Low-Level Waste; Environmental Monitoring and Performance; Greater Confinement and Alternative Disposal Methods; Low-Level Waste Management; Corrective Measures; Performance Prediction and Assessment; and Siting New Defense and Commercial Low-Level Waste Disposal Facilities.

  19. K130 beam current measurement system

    NASA Astrophysics Data System (ADS)

    Gustafsson, J.; Kotilainen, P.; Hänninen, V.; Liukkonen, E.; Kaski, K.

    1994-03-01

    A measurement system for very low currents, developed to be used in the K130 cyclotron at University of Jyväskylä, is described. The beam intensity measurement is implemented with a current preamplifier and signal multiplexor. The measurement is controlled and visualised with a commercial data acquisition card integrated in a PC.

  20. Measuring Electrical Current: The Roads Not Taken

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2011-01-01

    Recently I wrote about the standard Weston meter movement, that is at the heart of all modern analogue current measurements. Now I will discuss other techniques used to measure electric current that, despite being based on valid physical principles, are largely lost in technological history.

  1. Detecting low levels of radionuclides in fluids

    DOEpatents

    Patch, Keith D.; Morgan, Dean T.

    2000-01-01

    An apparatus and method for detecting low levels of one or more radionuclides in a fluid sample uses a substrate that includes an ion exchange resin or other sorbent material to collect the radionuclides. A collecting apparatus includes a collecting chamber that exposes the substrate to a measured amount of the fluid sample such that radionuclides in the fluid sample are collected by the ion exchange resin. A drying apparatus, which can include a drying chamber, then dries the substrate. A measuring apparatus measures emissions from radionuclides collected on the substrate. The substrate is positioned in a measuring chamber proximate to a detector, which provides a signal in response to emissions from the radionuclides. Other analysis methods can be used to detect non-radioactive analytes, which can be collected with other types of sorbent materials.

  2. R&D ERL: Low level RF

    SciTech Connect

    Smith, K.

    2010-01-15

    A superconducting RF (SRF) Energy Recovery Linac (ERL) is currently under development at the Collider-Accelerator Department (C-AD) at Brookhaven National Laboratory (BNL). The major components from an RF perspective are (a) a 5-cell SRF ERL cavity, (b) an SRF photocathode electron gun, and (c) a drive laser for the photocathode gun. Each of these RF subsystems has its own set of RF performance requirements, as well as common requirements for ensuring correct synchronism between them. A low level RF (LLRF) control system is currently under development, which seeks to leverage both technology and experience gained from the recently commissioned RHIC LLRF system upgrade. This note will review the LLRF system requirements and describe the system to be installed at the ERL.

  3. The Great Plains low-level jet (LLJ) during the atmospheric radiation measurement (ARM) intensive observation period (IOP)-4 and simulations of land use pattern effect on the LLJ

    SciTech Connect

    Wu, Y.; Raman, S.

    1996-04-01

    The Great Plains low-level jet (LLJ) is an important element of the low-level atmospheric circulation. It transports water vapor from the Gulf of Mexico, which in turn affects the development of weather over the Great Plains of the central United States. The LLJ is generally recognized as a complex response of the atmospheric boundary layer to the diurnal cycle of thermal forcing. Early studies have attributed the Great Plains LLJ to the diurnal oscillations of frictional effect, buoyancy over sloping terrain, and the blocking effects of the Rocky Mountains. Recent investigations show that the speed of the LLJ is also affected by the soil type and soil moisture. Some studies also suggest that synoptic patterns may play an important role in the development of the LLJ. Land surface heterogeneties significantly affect mesoscale circulations by generating strong contrasts in surface thermal fluxes. Thus one would expect that the land use pattern should have effects on the LLJ`s development and structure. In this study, we try to determine the relative roles of the synoptic forcing, planetary boundary layers (PBL) processes, and the land use pattern in the formation of the LLJ using the observations from the Atmospheric Radiation Measurement (ARM) Intensive Operation Period (IOP)-4 and numerical sensitivity tests.

  4. Russian low-level waste disposal program

    SciTech Connect

    Lehman, L.

    1993-03-01

    The strategy for disposal of low-level radioactive waste in Russia differs from that employed in the US. In Russia, there are separate authorities and facilities for wastes generated by nuclear power plants, defense wastes, and hospital/small generator/research wastes. The reactor wastes and the defense wastes are generally processed onsite and disposed of either onsite, or nearby. Treating these waste streams utilizes such volume reduction techniques as compaction and incineration. The Russians also employ methods such as bitumenization, cementation, and vitrification for waste treatment before burial. Shallow land trench burial is the most commonly used technique. Hospital and research waste is centrally regulated by the Moscow Council of Deputies. Plans are made in cooperation with the Ministry of Atomic Energy. Currently the former Soviet Union has a network of low-level disposal sites located near large cities. Fifteen disposal sites are located in the Federal Republic of Russia, six are in the Ukraine, and one is located in each of the remaining 13 republics. Like the US, each republic is in charge of management of the facilities within their borders. The sites are all similarly designed, being modeled after the RADON site near Moscow.

  5. Apparatus and method for critical current measurements

    DOEpatents

    Martin, Joe A.; Dye, Robert C.

    1992-01-01

    An apparatus for the measurement of the critical current of a superconductive sample, e.g., a clad superconductive sample, the apparatus including a conductive coil, a means for maintaining the coil in proximity to a superconductive sample, an electrical connection means for passing a low amplitude alternating current through the coil, a cooling means for maintaining the superconductive sample at a preselected temperature, a means for passing a current through the superconductive sample, and, a means for monitoring reactance of the coil, is disclosed, together with a process of measuring the critical current of a superconductive material, e.g., a clad superconductive material, by placing a superconductive material into the vicinity of the conductive coil of such an apparatus, cooling the superconductive material to a preselected temperature, passing a low amplitude alternating current through the coil, the alternating current capable of generating a magnetic field sufficient to penetrate, e.g., any cladding, and to induce eddy currents in the superconductive material, passing a steadily increasing current through the superconductive material, the current characterized as having a different frequency than the alternating current, and, monitoring the reactance of the coil with a phase sensitive detector as the current passed through the superconductive material is steadily increased whereby critical current of the superconductive material can be observed as the point whereat a component of impedance deviates.

  6. Draft low level waste technical summary

    SciTech Connect

    Powell, W.J.; Benar, C.J.; Certa, P.J.; Eiholzer, C.R.; Kruger, A.A.; Norman, E.C.; Mitchell, D.E.; Penwell, D.E.; Reidel, S.P.; Shade, J.W.

    1995-09-01

    The purpose of this document is to present an outline of the Hanford Site Low-Level Waste (LLW) disposal program, what it has accomplished, what is being done, and where the program is headed. This document may be used to provide background information to personnel new to the LLW management/disposal field and to those individuals needing more information or background on an area in LLW for which they are not familiar. This document should be appropriate for outside groups that may want to learn about the program without immediately becoming immersed in the details. This document is not a program or systems engineering baseline report, and personnel should refer to more current baseline documentation for critical information.

  7. Measurement of breakdown current in dielectric materials

    NASA Astrophysics Data System (ADS)

    Pakhotin, V. A.; Zakrevskii, V. A.; Sudar', N. T.

    2015-08-01

    A new method to determine the resistance of the breakdown channel, current, and characteristic time is based on the measurements of the breakdown current pulse in a wide range of parameters of the measurement circuit. A problem with time-dependent resistance of the breakdown channel is numerically solved. An experimental variation in the resistance of the breakdown channel can be used to estimate the breakdown time. The method is tested with the aid of computer experiments and employed in the analysis of oscillograms of breakdown current in experiments with a dielectric polymer.

  8. Electromagnetic pulse-induced current measurement device

    NASA Astrophysics Data System (ADS)

    Gandhi, Om P.; Chen, Jin Y.

    1991-08-01

    To develop safety guidelines for exposure to high fields associated with an electromagnetic pulse (EMP), it is necessary to devise techniques that would measure the peak current induced in the human body. The main focus of this project was to design, fabricate, and test a portable, self-contained stand-on device that would measure and hold the peak current and the integrated change Q. The design specifications of the EMP-Induced Current Measurement Device are as follows: rise time of the current pulse, 5 ns; peak current, 20-600 A; charge Q, 0-20 microcoulombs. The device uses a stand-on parallel-plate bilayer sensor and fast high-frequency circuit that are well-shielded against spurious responses to high incident fields. Since the polarity of the incident peak electric field of the EMP may be either positive or negative, the induced peak current can also be positive or negative. Therefore, the device is designed to respond to either of these polarities and measure and hold both the peak current and the integrated charge which are simultaneously displayed on two separate 3-1/2 digit displays. The prototype device has been preliminarily tested with the EMP's generated at the Air Force Weapons Laboratory (ALECS facility) at Kirtland AFB, New Mexico.

  9. Noncontact Measurement Of Critical Current In Superconductor

    NASA Technical Reports Server (NTRS)

    Israelsson, Ulf E.; Strayer, Donald M.

    1992-01-01

    Critical current measured indirectly via flux-compression technique. Magnetic flux compressed into gap between superconductive hollow cylinder and superconductive rod when rod inserted in hole in cylinder. Hall-effect probe measures flux density before and after compression. Method does not involve any electrical contact with superconductor. Therefore, does not cause resistive heating and consequent premature loss of superconductivity.

  10. Low level counting from meteorites to neutrinos

    SciTech Connect

    Heusser, Gerd

    2005-09-08

    The development in low level counting at Heidelberg with NaI(Tl) crystals, proportional counters and Germanium detectors is reviewed throughout the course of almost 40 years of experience. Research subjects changed from cosmogenic radionuclides in meteorites to solar neutrinos and double beta decay. Driven by screening measurements for these rare event experiments, the sensitivity in single gamma counting has gained almost 3 orders of magnitude. With Ge spectrometry the {mu}Bq/kg range is now accessible. It is discussed how further improvements can be realized. There is potential to reach a sensitivity at the level of 10 to 100 nBq/kg for cryogenic liquid type Gespectroscopy, a technique which the next generation 76Ge double beta decay experiment GERDA is based on.

  11. Low-level waste program technical strategy

    SciTech Connect

    Bledsoe, K.W.

    1994-10-01

    The Low-Level Waste Technical Strategy document describes the mechanisms which the Low-Level Waste Program Office plans to implement to achieve its mission. The mission is to manage the receipt, immobilization, packaging, storage/disposal and RCRA closure (of the site) of the low-level Hanford waste (pretreated tank wastes) in an environmentally sound, safe and cost-effective manner. The primary objective of the TWRS Low-level waste Program office is to vitrify the LLW fraction of the tank waste and dispose of it onsite.

  12. Deconvolving Current from Faraday Rotation Measurement

    SciTech Connect

    Stephen E. Mitchell

    2008-02-01

    In this paper, a unique software program is reported which automatically decodes the Faraday rotation signal into a time-dependent current representation. System parameters, such as the Faraday fiber’s Verdet constant and number of loops in the sensor, are the only user-interface inputs. The central aspect of the algorithm utilizes a short-time Fourier transform, which reveals much of the Faraday rotation measurement’s implicit information necessary for unfolding the dynamic current measurement.

  13. Current measurement by Faraday effect on GEPOPU

    NASA Astrophysics Data System (ADS)

    N, Correa; H, Chuaqui; E, Wyndham; F, Veloso; J, Valenzuela; M, Favre; H, Bhuyan

    2014-05-01

    The design and calibration of an optical current sensor using BK7 glass is presented. The current sensor is based on the polarization rotation by Faraday effect. GEPOPU is a pulsed power generator, double transit time 120ns, 1.5 Ohm impedance, coaxial geometry, where Z pinch experiment are performed. The measurements were performed at the Optics and Plasma Physics Laboratory of Pontificia Universidad Catolica de Chile. The verdet constant for two different optical materials was obtained using He-Ne laser. The values obtained are within the experimental error bars of measurements published in the literature (less than 15% difference). Two different sensor geometries were tried. We present the preliminary results for one of the geometries. The values obtained for the current agree within the measurement error with those obtained by means of a Spice simulation of the generator. Signal traces obtained are completely noise free.

  14. Variable-Temperature Critical-Current Measurements

    SciTech Connect

    L. F. Goodrich; T. C. Stauffer

    2009-05-19

    This is the final report of a three year contract that covered 09/19/2005 to 07/14/2008. We requested and received a no cost time extension for the third year, 07/15/2007 to 07/14/2008, to allow DoE to send us funds if they became available during that year. It turned out that we did not receive any funding for the third year. The following paper covers our variable-temperature critical-current measurements. We made transport critical-current (Ic) measurements on commercial multifilamentary Nb3Sn strands at temperatures (T) from 4 to 17 K and magnetic fields (H) from 0 to 14 T. One of the unique features of our measurements is that we can cover a wide range of critical currents from less than 0.1 A to over 700 A.

  15. Low level lead inhibits the human brain cation pump

    SciTech Connect

    Bertoni, J.M.; Sprenkle, P.M. )

    1991-01-01

    The impact of low level lead exposure on human central nervous system function is a major public health concern. This study addresses the inhibition of the cation pump enzyme Na,K-ATPase by low level lead. Human brain tissue was obtained at autopsy and frozen until use. Brain homogenates were preincubated with PbCl{sub 2} for 20 min at 0{degree}C. Inhibition of K-paranitrophenylphosphatase (pNPPase), a measure of the dephosphorylation step of Na,K-ATPase, reached steady state within 10 min. K-pNPPase activity, expressed as a percentage of control, fell to 96.3 {plus minus} 0.9% at 0.25 uM (PbCl{sub 2}) to 82.0 {plus minus} 1.6% at 2.5 uM (PbCl{sub 2}) in homogenates prepared from normal brain. Similar results were obtained with homogenates prepared from brains of patients with a history of alcohol abuse and of those with other miscellaneous conditions. Since the mean blood level of lead in the US has ranged recently from m9.2 to 16.0 ug/dl, these results indicate that current in vivo levels of lead exposure may impair important human brain function.

  16. LOWCAL Ground Receiver: PMT Dark Current Measurement

    NASA Technical Reports Server (NTRS)

    MacCannell, John

    2001-01-01

    This paper is part of a series of papers for a research project at New Mexico State University. The project is referred to as LOWCAL or Lightweight Optical Wavelength Communications without A Laser in space. While some of the material presented is specific to tile LOWCAL project, the general procedure for measuring the dark current of a photomultiplier tube is presented.

  17. Quantitative current measurements using scanning magnetoresistance microscopy.

    PubMed

    Takezaki, Taiichi; Sueoka, Kazuhisa

    2008-08-01

    We have demonstrated the capability of scanning magnetoresistance microscope (SMRM) to be used for quantitative current measurements. The SMRM is a magnetic microscope that is based on an atomic force microscope (AFM) and simultaneously measures the localized surface magnetic field distribution and surface topography. The proposed SMRM employs an in-house built AFM cantilever equipped with a miniaturized magnetoresistive (MR) sensor as a magnetic field sensor. In this study, a spin-valve type MR sensor with a width of 1 microm was used to measure the magnetic field distribution induced by a current carrying wire with a width of 5 microm and a spacing of 1.6 microm at room temperature and under ambient conditions. Simultaneous imaging of the magnetic field distribution and the topography was successfully performed in the DC current ranging from 500 microA to 8 mA. The characterized SV sensor, which has a linear response to magnetic fields, offers the quantitative analysis of a magnetic field and current. The measured magnetic field strength was in good agreement with the result simulated using Biot-Savart's law. PMID:18599218

  18. Transportation and disposal configuration for DOE-managed low-level and mixed low-level waste

    SciTech Connect

    Johnsen, T.

    1993-06-01

    This report briefly examines the current U.S. Department of Energy complex-wide configuration for transportation and disposal of low-level and mixed low-level waste, and also retraces the historical sequence of events and rationale that has guided its development. The study determined that Nevada Test Site and the Hanford Site are the only two sites that currently provide substantial disposal services for offsite low-level waste generators. It was also determined that mixed low-level waste shipments are infrequent and are generally limited to shipments to offsite commercial treatment facilities or other Department of Energy sites for storage. The current alignment of generator to disposal site for low-level waste shipments is generally consistent with the programmatic mission of the generator; that is, defense-generated waste is shipped to the Nevada Test Site and research-generated waste is transported to the Hanford Site. The historical development of the current configuration was resurrected by retrieving Department of Energy documentation and interviewing both current and former department and contractor personnel. According to several accounts, the basic framework of the system was developed during the late 1970s, and was reportedly based on the ability of the disposal site to manage a given waste form. Documented evidence to support this reasoning, however, could not be uncovered.

  19. Eddy current measurement of tube element spacing

    DOEpatents

    Latham, Wayne Meredith; Hancock, Jimmy Wade; Grut, Jayne Marie

    1998-01-01

    A method of electromagnetically measuring the distance between adjacent tube elements in a heat exchanger. A cylindrical, high magnetic permeability ferrite slug is placed in the tube adjacent the spacing to be measured. A bobbin or annular coil type probe operated in the absolute mode is inserted into a second tube adjacent the spacing to be measured. From prior calibrations on the response of the eddy current coil, the signals from the coil, when sensing the presence of the ferrite slug, are used to determine the spacing between the tubes.

  20. Low-level waste forum meeting reports

    SciTech Connect

    Sternwheeler, W.D.E.

    1992-12-31

    This paper provides highlights from the 1992 winter meeting of the Low Level Radioactive Wastes Forum. Topics of discussion included: legal information; state and compact reports; freedom of information requests; and storage.

  1. Low-level waste forum meeting reports

    SciTech Connect

    1992-12-31

    This report provides highlights from the 1992 fall meeting of the Low LEvel Radioactive Waste Forum. Topics included: disposal options after 1992; interregional agreements; management alternatives; policy; and storage.

  2. Critical current density: Measurements vs. reality

    NASA Astrophysics Data System (ADS)

    Pan, A. V.; Golovchanskiy, I. A.; Fedoseev, S. A.

    2013-07-01

    Different experimental techniques are employed to evaluate the critical current density (Jc), namely transport current measurements and two different magnetisation measurements forming quasi-equilibrium and dynamic critical states. Our technique-dependent results for superconducting YBa2Cu3O7 (YBCO) film and MgB2 bulk samples show an extremely high sensitivity of Jc and associated interpretations, such as irreversibility fields and Kramer plots, which lose meaning without a universal approach. We propose such approach for YBCO films based on their unique pinning features. This approach allows us to accurately recalculate the magnetic-field-dependent Jc obtained by any technique into the Jc behaviour, which would have been measured by any other method without performing the corresponding experiments. We also discovered low-frequency-dependent phenomena, governing flux dynamics, but contradicting the considered ones in the literature. The understanding of these phenomena, relevant to applications with moving superconductors, can clarify their dramatic impact on the electric-field criterion through flux diffusivity and corresponding measurements.

  3. Development of a low-level (37)Ar calibration standard.

    PubMed

    Williams, R M; Aalseth, C E; Bowyer, T W; Day, A R; Fuller, E S; Haas, D A; Hayes, J C; Hoppe, E W; Humble, P H; Keillor, M E; LaFerriere, B D; Mace, E K; McIntyre, J I; Miley, H S; Myers, A W; Orrell, J L; Overman, C T; Panisko, M E; Seifert, A

    2016-03-01

    Argon-37 is an environmental signature of an underground nuclear explosion. Producing and quantifying low-level (37)Ar standards is an important step in the development of sensitive field measurement instruments. This paper describes progress at Pacific Northwest National Laboratory in developing a process to generate and quantify low-level (37)Ar standards, which can be used to calibrate sensitive field systems at activities consistent with soil background levels. This paper presents a discussion of the measurement analysis, along with assumptions and uncertainty estimates. PMID:26701655

  4. High Current Hollow Cathode Plasma Plume Measurements

    NASA Technical Reports Server (NTRS)

    Thomas, Robert E.; Kamhawi, Hani; Williams, George J., Jr.

    2013-01-01

    Plasma plume measurements are reported for a hollow cathode assembly (HCA) oper-ated at discharge currents of 50, 70, and 100 A at xenon ow rates between 19 - 46 sccm.The HCA was centrally mounted in the annulus of the NASA-300MS Hall Thruster andwas operated in the spot and plume modes with additional data taken with an appliedmagnetic eld. Langmuir probes, retarding potential analyzers, and optical emission spec-troscopy were employed to measure plasma properties near the orice of the HCA and toassess the charge state of the near-eld plasma. Electron temperatures (2-6 eV) and plasmapotentials are consistent with probe-measured values in previous investigations. Operationwith an applied-eld yields higher discharge voltages, increased Xe III production, andincreased signals from the 833.5 nm C I line. While operating in plume mode and with anapplied eld, ion energy distribution measurements yield ions with energies signicantlyexceeding the applied discharge voltage. These ndings are correlated with high-frequencyoscillations associated with each mode.

  5. High Current Hollow Cathode Plasma Plume Measurements

    NASA Technical Reports Server (NTRS)

    Thomas, Robert E.; Kamhawi, Hani; Williams, George J., Jr.

    2014-01-01

    Plasma plume measurements are reported for a hollow cathode assembly (HCA) operated at discharge currents of 50, 70, and 100 A at xenon flow rates between 19 - 46 standard cubic centimeter per minute. The HCA was centrally mounted in the NASA-300MS Hall Thruster and was operated in the "spot" and "plume" modes with additional data taken with an applied magnetic field. Langmuir probes, retarding potential analyzers, and optical emission spectroscopy were employed to measure plasma properties near the orifice of the HCA and to assess the charge state of the near-field plasma. Electron temperatures (2-6 electron volt) and plasma potentials are consistent with probe-measured values in previous investigations. Operation with an applied-field yields higher discharge voltages, increased Xe III production, and increased signals from the 833.5 nm C I line. While operating in plume mode and with an applied field, ion energy distribution measurements yield ions with energies significantly exceeding the applied discharge voltage. These findings are correlated with high-frequency oscillations associated with each mode.

  6. Determination of tunneling charge via current measurements

    NASA Astrophysics Data System (ADS)

    Safi, I.; Sukhorukov, E. V.

    2010-09-01

    We consider a tunnel junction between two arbitrary non-linear systems in any dimension, which can be different. We show that the tunneling charge can be detected using three alternative methods based on current measurements. Besides being technically easier compared to noise measurements, these methods present valuable advantages: they do not require the knowledge of the underlying models, and some are accessible in the experimentally convenient low-voltage regime, where heating effects are reduced. The first method is based on the AC conductance, while the two others are based on photo-assisted current (PAC) and can be implemented for any time dependence of the tunneling amplitude. These are promising for edge states in the regime of the fractional quantum Hall effect (FQHE): the Hamiltonian does not have to be specified and can incorporate non-universal interactions between the edges, and it is more convenient to use an AC gate voltage rather than an AC bias. These methods apply for instance to weak barriers in 1-D systems, Superconductor-Insulator-Normal (SIN) or graphene-like structures.

  7. Induced Current Measurement of Rod Vibrations

    NASA Astrophysics Data System (ADS)

    Sawicki, Charles A.

    2003-01-01

    The longitudinal normal modes of vibration of rods are similar to the modes seen in pipes open at both ends. A maximum of particle displacement exists at both ends and an integral number (n) of half wavelengths fit into the rod length. The frequencies fn of the normal modes is given by Eq. (1), where L is the rod length and V is the wave velocity: fn = nV/2L. Many methods have been used to measure the velocity of these waves. The Kundt's tube method commonly used in student labs will not be discussed here. A simpler related method has been described by Nicklin.2 Kluk3 measured velocities in a wide range of materials using a frequency counter and microphone to study sounds produced by impacts. Several earlier methods4,5 used phonograph cartridges complete with needles to detect vibrations in excited rods. A recent interesting experiment6 used wave-induced changes in magnetization produced in an iron rod by striking one end. The travel time, measured as the impulsive wave reflects back and forth, gave the wave velocity for the iron rod. In the method described here, a small magnet is attached to the rod with epoxy, and vibrations are detected using the current induced in a few loops of wire. The experiment is simple and yields very accurate velocity values.

  8. Low-level waste forum meeting reports

    SciTech Connect

    1993-12-31

    This paper provides the results of the winter meeting of the Low Level Radioactive Waste Forum. Discussions were held on the following topics: new developments in states and compacts; adjudicatory hearings; information exchange on siting processes, storage surcharge rebates; disposal after 1992; interregional access agreements; and future tracking and management issues.

  9. Low-level waste forum meeting reports

    SciTech Connect

    1990-12-31

    This paper provides highlights from the October 1990 meeting of the Low Level Radioactive Waste Forum. Topics of discussion included: a special session on liability and financial assurance needs; proposal to dispose of mixed waste at federal facilities; state plans for interim storage; and hazardous materials legislation.

  10. Low-level waste forum meeting reports

    SciTech Connect

    1991-12-31

    This report contains highlights from the 1991 fall meeting of the Low Level Radioactive Waste Forum. Topics included legal updates; US NRC updates; US EPA updates; mixed waste issues; financial assistance for waste disposal facilities; and a legislative and policy report.

  11. Natural Artificial Languages: Low-Level Processes.

    ERIC Educational Resources Information Center

    Perlman, Gary

    This paper explores languages for communicating precise ideas within limited domains, which include mathematical notation and general purpose and high level computer programming languages. Low-level properties of such natural artificial languages are discussed, with emphasis on those in which names are chosen for concepts and symbols are chosen…

  12. Infrared low-level wind shear work

    NASA Technical Reports Server (NTRS)

    Adamson, Pat

    1988-01-01

    Results of field experiments for the detection of clear air disturbance and low level wind shear utilizing an infrared airborne system are given in vugraph form. The hits, misses and nuisance alarms scores are given. Information is given on the infrared spatial resolution technique. The popular index of aircraft hazard (F= WX over g - VN over AS) is developed for a remote temperature sensor.

  13. Low Level Lead Toxicity: The Hidden Challenge for Educators.

    ERIC Educational Resources Information Center

    McCabe, Patrick P.

    1991-01-01

    Discusses the widespread problem of low level lead toxicity and how it affects young children's behavior and learning ability. Discusses what medical and environmental measures can be taken to remedy the problem. Briefly notes what role states have taken. Also suggests actions early childhood teachers can take to remedy the problem. (BB)

  14. Low-level bromate analysis in drinking water by ion chromatography with optimized suppressed conductivity cell current followed by a post-column reaction and UV/Vis detection.

    PubMed

    Fotsing, Marcellin; Barbeau, Benoit; Prevost, Michele

    2011-01-01

    In the present work, a high capacity anion exchange column was used to efficiently and simultaneously separate traces of oxyhalide disinfection byproducts (DBP) anions and bromide by an ion chromatography system followed by a post-column reaction (PCR). The PCR generates in situ hydroiodic (HI) acid from the excess of potassium iodate that combines with bromate from the column effluent to form the triiodide anion detectable by UV/Vis absorbance at 352 nm. The suppressed conductivity cell current was optimized at 70 mA, with a flow rate of 1.0 mL/min and a 9 mM carbonate eluent. Its performance was investigated on a trace-level determination of bromate in ozonated municipal and bottled drinking water. Based on ozonated municipal drinking water matrix, the method detection limit of 0.27 μg BrO(-)(3)/L was evaluated with the Method Quantification Limit (MQL) of 0.89 μg BrO(-)(3)/L. However, in ultrapure water, a MDL of 0.015 μg BrO(-)(3)/L and a MRL of 0.052 μg BrO(-)(3)/L were achieved. The recovery for spiked municipal samples was in the range of 90%-115%.

  15. Current trends to measure implant stability.

    PubMed

    Swami, Vasanthi; Vijayaraghavan, Vasantha; Swami, Vinit

    2016-01-01

    Implant stability plays a critical role for successful osseointegration. Successful osseointegration is a prerequisite for functional dental implants. Continuous monitoring in an objective and qualitative manner is important to determine the status of implant stability. Implant stability is measured at two different stages: Primary and secondary. Primary stability comes from mechanical engagement with cortical bone. Secondary stability is developed from regeneration and remodeling of the bone and tissue around the implant after insertion and affected by the primary stability, bone formation and remodelling. The time of functional loading is dependent upon the implant stability. Historically the gold standard method to evaluate stability were microscopic or histologic analysis, radiographs, however due to invasiveness of these methods and related ethical issues various other methods have been proposed like cutting torque resistance, reverse torque analysis, model analysis etc. It is, therefore, of an utmost importance to be able to access implant stability at various time points and to project a long term prognosis for successful therapy. Therefore this review focuses on the currently available methods for evaluation of implant stability.

  16. Expert system for analyzing eddy current measurements

    DOEpatents

    Levy, Arthur J.; Oppenlander, Jane E.; Brudnoy, David M.; Englund, James M.; Loomis, Kent C.

    1994-01-01

    A method and apparatus (called DODGER) analyzes eddy current data for heat exchanger tubes or any other metallic object. DODGER uses an expert system to analyze eddy current data by reasoning with uncertainty and pattern recognition. The expert system permits DODGER to analyze eddy current data intelligently, and obviate operator uncertainty by analyzing the data in a uniform and consistent manner.

  17. Dielectric Properties of Low-Level Liquid Waste

    SciTech Connect

    L. E. Lagos; M. A. Ebadian

    1998-10-20

    The purpose of this study was to develop a data collection containing values for the dielectric properties of various low-level liquid waste (LLLW) simulants measured as a function of frequency, temperature, and composition. The investigation was motivated by current interest in the use of microwave processing for the treatment of radioactive waste. A large volume of transuranic liquid and sludge produced by the U.S. Department of Defense (DOD) during the production of nuclear fiel bars is stored at several U.S. Department of Energy (DOE) sites around the United States. Waste storage and disposal space is scarce, expensive, and must be minimized. Thus, several DOE sites are pursuing the use of microwave heating as a means of achieving volume reduction and solidification of low-level liquid wastes. It is important to know which microwave frequencies should be employed tc achieve the most efficient processing at a range of different temperatures. The dielectric properties of the LLLW simulants can be utilized to determine the optimum frequencies for use with a particular LLLW or with other LLLWS of similar composition. Furthermore, nonlinear thermal processes, such as thermal runaway, which occur in the material being treated cannot be modeled without a knowledge of the temperature dependence of the dielectric properties. Often, this data does not exist; however, when it does, only very limited data near room temperature are available. The data collection generated in this study can be used to predict the behavior of a variety of microwave thermal treatment technologies, which have the potential of substantially reducing the volume of the LLLWS that are currently stored at many DOE sites. This information should help the users of the microwave reduction and solidification technology to optimize microwave processes used in the treatment of LLLW. The microwave reduction and solidification technology has clear advantages over other methods of reducing LLLWS. These

  18. Low-level radioactive waste disposal facility closure

    SciTech Connect

    White, G.J.; Ferns, T.W.; Otis, M.D.; Marts, S.T.; DeHaan, M.S.; Schwaller, R.G.; White, G.J. )

    1990-11-01

    Part I of this report describes and evaluates potential impacts associated with changes in environmental conditions on a low-level radioactive waste disposal site over a long period of time. Ecological processes are discussed and baselines are established consistent with their potential for causing a significant impact to low-level radioactive waste facility. A variety of factors that might disrupt or act on long-term predictions are evaluated including biological, chemical, and physical phenomena of both natural and anthropogenic origin. These factors are then applied to six existing, yet very different, low-level radioactive waste sites. A summary and recommendations for future site characterization and monitoring activities is given for application to potential and existing sites. Part II of this report contains guidance on the design and implementation of a performance monitoring program for low-level radioactive waste disposal facilities. A monitoring programs is described that will assess whether engineered barriers surrounding the waste are effectively isolating the waste and will continue to isolate the waste by remaining structurally stable. Monitoring techniques and instruments are discussed relative to their ability to measure (a) parameters directly related to water movement though engineered barriers, (b) parameters directly related to the structural stability of engineered barriers, and (c) parameters that characterize external or internal conditions that may cause physical changes leading to enhanced water movement or compromises in stability. Data interpretation leading to decisions concerning facility closure is discussed. 120 refs., 12 figs., 17 tabs.

  19. Liquid low level waste management expert system

    SciTech Connect

    Ferrada, J.J.; Abraham, T.J. ); Jackson, J.R. )

    1991-01-01

    An expert system has been developed as part of a new initiative for the Oak Ridge National Laboratory (ORNL) systems analysis program. This expert system will aid in prioritizing radioactive waste streams for treatment and disposal by evaluating the severity and treatability of the problem, as well as the final waste form. The objectives of the expert system development included: (1) collecting information on process treatment technologies for liquid low-level waste (LLLW) that can be incorporated in the knowledge base of the expert system, and (2) producing a prototype that suggests processes and disposal technologies for the ORNL LLLW system. 4 refs., 9 figs.

  20. Lid design for low level waste container

    DOEpatents

    Holbrook, Richard H.; Keener, Wendell E.

    1995-01-01

    A container for low level waste includes a shell and a lid. The lid has a frame to which a planar member is welded. The lid frame includes a rectangular outer portion made of square metal tubing, a longitudinal beam extending between axial ends of the rectangular outer portion, and a transverse beam extending between opposite lateral sides of the rectangular outer portion. Two pairs of diagonal braces extend between the longitudinal beam and the four corners of the rectangular outer portion of the frame.

  1. Low-level structural recognition of documents

    SciTech Connect

    Chenevoy, Y.; Belaied, A.

    1994-12-31

    This paper focuses on the qualitative approach of the low-level structured document analysis. The system identifies the different logical fields within the document and produces as output a structured flow with confidence scores. The strategy is driven by a generic model and by an OCR flow. Logical labels are attached to research areas after hypothesizing and testing typographical, lexical and contextual properties. A qualitative recognition is performed, which allows to amphasize ambiguities and unrecognized fields. Library references are treated to illustrate this method.

  2. Low level vapor verification of monomethyl hydrazine

    NASA Technical Reports Server (NTRS)

    Mehta, Narinder

    1990-01-01

    The vapor scrubbing system and the coulometric test procedure for the low level vapor verification of monomethyl hydrazine (MMH) are evaluated. Experimental data on precision, efficiency of the scrubbing liquid, instrument response, detection and reliable quantitation limits, stability of the vapor scrubbed solution, and interference were obtained to assess the applicability of the method for the low ppb level detection of the analyte vapor in air. The results indicated that the analyte vapor scrubbing system and the coulometric test procedure can be utilized for the quantitative detection of low ppb level vapor of MMH in air.

  3. Lid design for low level waste container

    DOEpatents

    Holbrook, R.H.; Keener, W.E.

    1995-02-28

    A container for low level waste includes a shell and a lid. The lid has a frame to which a planar member is welded. The lid frame includes a rectangular outer portion made of square metal tubing, a longitudinal beam extending between axial ends of the rectangular outer portion, and a transverse beam extending between opposite lateral sides of the rectangular outer portion. Two pairs of diagonal braces extend between the longitudinal beam and the four corners of the rectangular outer portion of the frame. 6 figs.

  4. Solid low-level waste certification strategy

    SciTech Connect

    Smith, M.A.

    1991-08-01

    The purpose of the Solid Low-Level Waste (SLLW) Certification Program is to provide assurance that SLLW generated at the ORNL meets the applicable waste acceptance criteria for those facilities to which the waste is sent for treatment, handling, storage, or disposal. This document describes the strategy to be used for certification of SLLW or ORNL. The SLLW Certification Program applies to all ORNL operations involving the generation, shipment, handling, treatment, storage and disposal of SLLW. Mixed wastes, containing both hazardous and radioactive constituents, and transuranic wastes are not included in the scope of this document. 13 refs., 3 figs.

  5. Flight in low-level wind shear

    NASA Technical Reports Server (NTRS)

    Frost, W.

    1983-01-01

    Results of studies of wind shear hazard to aircraft operation are summarized. Existing wind shear profiles currently used in computer and flight simulator studies are reviewed. The governing equations of motion for an aircraft are derived incorporating the variable wind effects. Quantitative discussions of the effects of wind shear on aircraft performance are presented. These are followed by a review of mathematical solutions to both the linear and nonlinear forms of the governing equations. Solutions with and without control laws are presented. The application of detailed analysis to develop warning and detection systems based on Doppler radar measuring wind speed along the flight path is given. A number of flight path deterioration parameters are defined and evaluated. Comparison of computer-predicted flight paths with those measured in a manned flight simulator is made. Some proposed airborne and ground-based wind shear hazard warning and detection systems are reviewed. The advantages and disadvantages of both types of systems are discussed.

  6. Low level tank waste disposal study

    SciTech Connect

    Mullally, J.A.

    1994-09-29

    Westinghouse Hanford Company (WHC) contracted a team consisting of Los Alamos Technical Associates (LATA), British Nuclear Fuel Laboratories (BNFL), Southwest Research Institute (SwRI), and TRW through the Tank Waste Remediation System (TWRS) Technical Support Contract to conduct a study on several areas concerning vitrification and disposal of low-level-waste (LLW). The purpose of the study was to investigate how several parameters could be specified to achieve full compliance with regulations. The most restrictive regulation governing this disposal activity is the National Primary Drinking Water Act which sets the limits of exposure to 4 mrem per year for a person drinking two liters of ground water daily. To fully comply, this constraint would be met independently of the passage of time. In addition, another key factor in the investigation was the capability to retrieve the disposed waste during the first 50 years as specified in Department of Energy (DOE) Order 5820.2A. The objective of the project was to develop a strategy for effective long-term disposal of the low-level waste at the Hanford site.

  7. Nulling Hall-Effect Current-Measuring Circuit

    NASA Technical Reports Server (NTRS)

    Sullender, Craig C.; Vazquez, Juan M.; Berru, Robert I.

    1993-01-01

    Circuit measures electrical current via combination of Hall-effect-sensing and magnetic-field-nulling techniques. Known current generated by feedback circuit adjusted until it causes cancellation or near cancellation of magnetic field produced in toroidal ferrite core by current measured. Remaining magnetic field measured by Hall-effect sensor. Circuit puts out analog signal and digital signal proportional to current measured. Accuracy of measurement does not depend on linearity of sensing components.

  8. Low-level radioactive waste technology: a selected, annotated bibliography

    SciTech Connect

    Fore, C.S.; Vaughan, N.D.; Hyder, L.K.

    1980-10-01

    This annotated bibliography of 447 references contains scientific, technical, economic, and regulatory information relevant to low-level radioactive waste technology. The bibliography focuses on environmental transport, disposal site, and waste treatment studies. The publication covers both domestic and foreign literature for the period 1952 to 1979. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Environmental Transport; General Studies and Reviews; Geology, Hydrology and Site Resources; Regulatory and Economic Aspects; Transportation Technology; Waste Production; and Waste Treatment. Specialized data fields have been incorporated into the data file to improve the ease and accuracy of locating pertinent references. Specific radionuclides for which data are presented are listed in the Measured Radionuclides field, and specific parameters which affect the migration of these radionuclides are presented in the Measured Parameters field. In addition, each document referenced in this bibliography has been assigned a relevance number to facilitate sorting the documents according to their pertinence to low-level radioactive waste technology. The documents are rated 1, 2, 3, or 4, with 1 indicating direct applicability to low-level radioactive waste technology and 4 indicating that a considerable amount of interpretation is required for the information presented to be applied. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. Indexes are provide for (1) author(s), (2) keywords, (3) subject category, (4) title, (5) geographic location, (6) measured parameters, (7) measured radionuclides, and (8) publication description.

  9. Mixed and low-level waste treatment facility project

    SciTech Connect

    Not Available

    1992-04-01

    The technology information provided in this report is only the first step toward the identification and selection of process systems that may be recommended for a proposed mixed and low-level waste treatment facility. More specific information on each technology will be required to conduct the system and equipment tradeoff studies that will follow these preengineering studies. For example, capacity, maintainability, reliability, cost, applicability to specific waste streams, and technology availability must be further defined. This report does not currently contain all needed information; however, all major technologies considered to be potentially applicable to the treatment of mixed and low-level waste are identified and described herein. Future reports will seek to improve the depth of information on technologies.

  10. Low level laser therapy reduces inflammation in activated Achilles tendinitis

    NASA Astrophysics Data System (ADS)

    Bjordal, Jan M.; Iversen, Vegard; Lopes-Martins, Rodrigo Alvaro B.

    2006-02-01

    Objective: Low level laser therapy (LLLT) has been forwarded as therapy for osteoarthritis and tendinopathy. Results in animal and cell studies suggest that LLLT may act through a biological mechanism of inflammatory modulation. The current study was designed to investigate if LLLT has an anti-inflammatory effect on activated tendinitis of the Achilles tendon. Methods: Seven patients with bilateral Achilles tendonitis (14 tendons) who had aggravated symptoms by pain-inducing activity immediately prior to the study. LLLT (1.8 Joules for each of three points along the Achilles tendon with 904nm infrared laser) and placebo LLLT were administered to either Achilles tendons in a random order to which patients and therapist were blinded. Inflammation was examined by 1) mini-invasive microdialysis for measuring the concentration of inflammatory marker PGE II in the peritendinous tissue, 2) ultrasound with Doppler measurement of peri- and intratendinous blood flow, 3) pressure pain algometry and 4) single hop test. Results: PGE 2- levels were significantly reduced at 75, 90 and 105 minutes after active LLLT compared both to pre-treatment levels (p=0.026) and to placebo LLLT (p=0.009). Changes in pressure pain threshold (PPT) were significantly different (P=0.012) between groups. PPT increased by a mean value of 0.19 kg/cm2 [95%CI:0.04 to 0.34] after treatment in the active LLLT group, while pressure pain threshold was reduced by -0.20 kg/cm2 [95%CI:-0.45 to 0.05] after placebo LLLT. Conclusion: LLLT can be used to reduce inflammatory musculskeletal pain as it reduces inflammation and increases pressure pain threshold levels in activity-induced pain episodes of Achilles tendinopathy.

  11. The low-level radioactivity ocean sediment standard reference material

    SciTech Connect

    Inn, K.G.W.; Lin, Z.; Liggett, W.S.; Krey, P.W.

    1995-12-31

    Over the past decades, on the order of 10{sup 15} Becquerel nuclear waste have been stored in the oceans. Potential contamination of the oceans from leaking nuclear waste has caused world wide concern. Currently, early warning of ocean contamination near the waste dumping sites rely on monitoring systems being set up by different countries and agencies. Because the determination of low-level radioactivity in ocean sediment is a difficult technical task, a basis for measurement quality assurance, methods verification, and data comparability is needed. The recently certified NIST ocean sediment Standard Reference Material (SRM-4355) is a composite of 1% contaminated Irish Sea sediment and 99% of Chesapeake Bay sediment by weight. The sediments were blended, pulverized to a median particle size of 8 {mu}m, and reblended to achieve acceptable sample homogeneity. A statistical assessment of the intercomparison results from 19 laboratories has shown the material to be homogeneous down to 10 grams. The certified radionuclide concentration range from 0.4 to 230 mBq/g. A variety of radiochemical procedures and detection techniques have been used in the measurements to minimize possible systematic bias. Twelve radionuclides including {sup 40}K, {sup 90}Sr, {sup 137}Cs, {sup 226}Ra, {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 234}U, {sup 235}U, {sup 238}U, {sup 238}Pu, and {sup (239+240)}Pu were certified. The mean values were reported for an additional 10 uncertified radionuclides: {sup 129}I, {sup 155}Eu, {sup 210}Po, {sup 210}Pb, {sup 212}Pb, {sup 214}Pb, {sup 214}Bi, {sup 228}Ra, {sup 237}Np, and {sup 241}Am. The standard reference material in unit quantities of about 100 gram each will be available by the end of 1995.

  12. 48-Pack low level waste storage facility

    SciTech Connect

    Bilik, T.J.

    1995-11-01

    ComEd has completed a design for a low level radioactive waste (LLW) storage facility, dubbed the {open_quotes}48-Pack{close_quotes}. The 48-Pack, so named because of its ability to hold 48 high integrity containers (HICs), is a modular, heavily shielded, concrete bunker. The facility was designed to serve as an effective means of augmenting the Company`s existing process waste storage capacity if and when the need arose. This paper identifies how ComEd addressed the potential need to supplement the storage capacity at its six nuclear stations through the development of the 48-Pack. Based on the criteria of meeting safety and regulatory requirements, low cost, short lead time for construction, universal design, and modularity, the 48-Pack concept was anticipated to meet and exceed the Company`s storage needs which were anticipated to end with the availability of a Central Midwest Compact (CMC) disposal facility.

  13. Low-level therapy in ophthalmology

    NASA Astrophysics Data System (ADS)

    Pankov, O. P.

    1999-07-01

    Extremely slow introduction of low-level laser therapy into the practice of ophthalmologists is restricted by the lack of good methodological recommendation and modern equipment adopted to the needs of ophthalmology. The most perspective is considered to be further improvement of the methods and the elaboration of the medical equipment, working in several wave bands, combined with magnetotherapy and working with the use of various modes of the modulation of the intensity of the luminous flux. It may be asserted that unlike the mode of continuous radiation, in some cases, the effectiveness of the treatment increases when the modulated light with the frequency of one to a few tens HZ is used. Moreover, the methods are being elaborated, when the modulation frequency of laser light and the biorhythms of man physiologic parameters are synchronized. Very perspective seems the computerization of the treatment process with the simultaneous electrophysiological control of the condition of visual functions.

  14. Statistical analysis of low level atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Tieleman, H. W.; Chen, W. W. L.

    1974-01-01

    The statistical properties of low-level wind-turbulence data were obtained with the model 1080 total vector anemometer and the model 1296 dual split-film anemometer, both manufactured by Thermo Systems Incorporated. The data obtained from the above fast-response probes were compared with the results obtained from a pair of Gill propeller anemometers. The digitized time series representing the three velocity components and the temperature were each divided into a number of blocks, the length of which depended on the lowest frequency of interest and also on the storage capacity of the available computer. A moving-average and differencing high-pass filter was used to remove the trend and the low frequency components in the time series. The calculated results for each of the anemometers used are represented in graphical or tabulated form.

  15. Polyethylene solidification of low-level wastes

    NASA Astrophysics Data System (ADS)

    Kalb, P. D.; Colombo, P.

    1985-02-01

    The results of an investigation on the solidification of low-level radioactive waste in polyethylene are discussed. Waste streams included those which result from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Four types of commercially available low-density polyethylenes were employed which encompass a range of processing and property characteristics. Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste and polyethylene type. Property evaluation testing was performed on laboratory-scale specimens to assess the potential behavior of actual waste forms in a disposal environment.

  16. Mechanisms of low level light therapy

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.; Demidova, Tatiana N.

    2006-02-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage has been known for almost forty years since the invention of lasers. Originally thought to be a peculiar property of laser light (soft or cold lasers), the subject has now broadened to include photobiomodulation and photobiostimulation using non-coherent light. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. This likely is due to two main reasons; firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. In particular a biphasic dose response has been frequently observed where low levels of light have a much better effect than higher levels. This introductory review will cover some of the proposed cellular chromophores responsible for the effect of visible light on mammalian cells, including cytochrome c oxidase (with absorption peaks in the near infrared) and photoactive porphyrins. Mitochondria are thought to be a likely site for the initial effects of light, leading to increased ATP production, modulation of reactive oxygen species and induction of transcription factors. These effects in turn lead to increased cell proliferation and migration (particularly by fibroblasts), modulation in levels of cytokines, growth factors and inflammatory mediators, and increased tissue oxygenation. The results of these biochemical and cellular changes in animals and patients include such benefits as increased healing in chronic wounds, improvements in sports injuries and

  17. Faster Hall-Effect Current-Measuring Circuit

    NASA Technical Reports Server (NTRS)

    Sullender, Craig C.; Johnson, Daniel D.; Walker, Daniel D.

    1993-01-01

    Current-measuring circuit operates on Hall-effect-sensing and magnetic-field-nulling principles similar to those described in article, "Nulling Hall-Effect Current-Measuring Circuit" (LEW-15023), but simpler and responds faster. Designed without feedback loop, and analog pulse-width-modulated output indicates measured current. Circuit measures current at frequency higher than bandwidth of its Hall-effect sensor.

  18. Immobilization of low level hazardous organics using recycled materials

    SciTech Connect

    Conner, J.R.; Smith, F.G.

    1996-12-31

    Rust Remedial Services, Inc. (RRS) recently conducted a major study on the effectiveness of additives, both virgin and recycled, in the immobilization of low-level organics in soils. Using a clean soil spiked with a mixture of hazardous organic chemicals, twelve different stabilization formulations were comparatively tested using leaching (TCLP) and total analysis (TCA) methods. TCLP reduction levels illustrated the effectiveness of the stabilization treatment on a wide variety of low level organics in contaminated soil, with the proper selection of stabilization admixtures. A specially prepared, comminuted, rubber particulate was especially effective in reducing the apparent presence of certain semi-volatile organic compounds in soil, as measured by TCA methods. Most semi-volatile organic compounds were so strongly held by the rubber particles that they were not recovered in the analytical procedure.

  19. Disposal of low-level and low-level mixed waste: audit report

    SciTech Connect

    1998-09-03

    The Department of Energy (Department) is faced with the legacy of thousands of contaminated areas and buildings and large volumes of `backlog` waste requiring disposal. Waste management and environmental restoration activities have become central to the Department`s mission. One of the Department`s priorities is to clean up former nuclear weapons sites and find more effective and timely methods for disposing of nuclear waste. This audit focused on determining if the Department was disposing of low-level and low-level mixed waste in the most cost-effective manner.

  20. Forearm muscle oxygenation decreases with low levels of voluntary contraction

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Kahan, N. J.; Hargens, A. R.; Rempel, D. M.

    1997-01-01

    The purpose of our investigation was to determine if the near infrared spectroscopy technique was sensitive to changes in tissue oxygenation at low levels of isometric contraction in the extensor carpi radialis brevis muscle. Nine subjects were seated with the right arm abducted to 45 degrees, elbow flexed to 85 degrees, forearm pronated 45 degrees, and wrist and forearm supported on an armrest throughout the protocol. Altered tissue oxygenation was measured noninvasively with near infrared spectroscopy. The near infrared spectroscopy probe was placed over the extensor carpi radialis brevis of the subject's right forearm and secured with an elastic wrap. After 1 minute of baseline measurements taken with the muscle relaxed, four different loads were applied just proximal to the metacarpophalangeal joint such that the subjects isometrically contracted the extensor carpi radialis brevis at 5, 10, 15, and 50% of the maximum voluntary contraction for 1 minute each. A 3-minute recovery period followed each level of contraction. At the end of the protocol, with the probe still in place, a value for ischemic tissue oxygenation was obtained for each subject. This value was considered the physiological zero and hence 0% tissue oxygenation. Mean tissue oxygenation (+/-SE) decreased from resting baseline (100% tissue oxygenation) to 89 +/- 4, 81 +/- 8, 78 +/- 8, and 47 +/- 8% at 5, 10, 15, and 50% of the maximum voluntary contraction, respectively. Tissue oxygenation levels at 10, 15, and 50% of the maximum voluntary contraction were significantly lower (p < 0.05) than the baseline value. Our results indicate that tissue oxygenation significantly decreases during brief, low levels of static muscle contraction and that near infrared spectroscopy is a sensitive technique for detecting deoxygenation noninvasively at low levels of forearm muscle contraction. Our findings have important implications in occupational medicine because oxygen depletion induced by low levels of muscle

  1. Low-level Waste Forum meeting report. Winter meeting, January 26--28, 1994

    SciTech Connect

    1994-12-31

    The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. The Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This report contains information synthesizing the accomplishments of the Forum, as well as any new advances that have been made in the management of low-level radioactive wastes.

  2. Low-Level Waste Forum meeting report. Quarterly meeting, April 25--27, 1990

    SciTech Connect

    1990-12-31

    The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. The Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This report contains information synthesizing the accomplishments of the Forum, as well as any new advances that have been made in the management of low-level radioactive wastes.

  3. Low-Level Waste Forum meeting report. Quarterly meeting, July 23--24, 1990

    SciTech Connect

    1990-12-31

    The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. The Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This report contains information synthesizing the accomplishments of the Forum, as well as any new advances that have been made in the management of low-level radioactive wastes.

  4. Low-level Waste Forum meeting report. Quarterly meeting, July 25--26, 1991

    SciTech Connect

    1991-12-31

    The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. The Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This report contains information synthesizing the accomplishments of the Forum, as well as any new advances that have been made in the management of low-level radioactive wastes.

  5. Health-promoting low level laser therapy

    NASA Astrophysics Data System (ADS)

    Yuan, Jian-Qin; Liu, Timon Cheng-Yi; Li, Jiang-Hua; Liu, Xiao-Guang; Xu, Xiao-Yang; Liu, Song-Hao

    2008-12-01

    Homeostasis is a classical concept of physiology, and will be developed into function-specific homeostasis (FSH) in this paper. FSH is a negative-feedback response of a biosystem to maintain the function-specific conditions inside the biosystem. Let Q be the quality of a FSH. A person might simultaneously have many kinds of FSH, {FSHi, i = 1, 2,... n}, and then has {Qi, i = 1, 2,...,n}. Let Qmax=max{Qi, i = 1, 2,...n}. Qmax represents the health level, and might be enhanced by training. An individual system might be classified as FSH-essential subsystems (FESs) and FSH-non-essential subsystems (FNSs) which homeostasis can be written as FESHs and FNSHs for short, respectively. The training to establish a new FSH can also be classified as extraordinary training (ET) and ordinary training (OT). ET disrupts the present FSH and establishes FESHs. OT maintains FESHs and establishes FNSHs and then a new FSH, and then maintains the new FSH. The cellular rehabilitation of low level laser irradiation or monochromatic light might promote the establishment of FESHs, FNSHs and then FSH, shorten ET or OT period and then promote health.

  6. Language abstractions for low level optimization techniques

    NASA Astrophysics Data System (ADS)

    Dévai, Gergely; Gera, Zoltán; Kelemen, Zoltán

    2012-09-01

    In case of performance critical applications programmers are often forced to write code at a low abstraction level. This leads to programs that are hard to develop and maintain because the program text is mixed up by low level optimization tricks and is far from the algorithm it implements. Even if compilers are smart nowadays and provide the user with many automatically applied optimizations, practice shows that in some cases it is hopeless to optimize the program automatically without the programmer's knowledge. A complementary approach is to allow the programmer to fine tune the program but provide him with language features that make the optimization easier. These are language abstractions that make optimization techniques explicit without adding too much syntactic noise to the program text. This paper presents such language abstractions for two well-known optimizations: bitvectors and SIMD (Single Instruction Multiple Data). The language features are implemented in the embedded domain specific language Feldspar which is specifically tailored for digital signal processing applications. While we present these language elements as part of Feldspar, the ideas behind them are general enough to be applied in other language definition projects as well.

  7. Low-level efficacy of cosmetic preservatives.

    PubMed

    Lundov, M D; Johansen, J D; Zachariae, C; Moesby, L

    2011-04-01

    Preservation using combinations of preservatives has several advantages. This study shows that the concentration of some of the most frequently used allergenic preservatives can be markedly lowered when they are combined with phenoxyethanol. The antimicrobial efficacy of cosmetic preservatives and known allergens of various potency [diazolidinyl urea, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), methylisothiazolinone (MI) and phenoxyethanol] was tested alone and in various combinations of two or three preservatives together. The preservatives were tested for minimum inhibitory concentration (MIC) values and possible synergy using fractional inhibitory concentration. MCI/MI was the only preservative showing low-level MIC against all four tested microorganisms: Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. Different combinations of the preservatives indicated additive effects against the microorganisms. No combination of preservatives showed any inhibitory action on each other. Challenge tests with different concentrations and combinations were performed in a cosmetic cream. Diazolidinyl urea and MCI/MI alone were ineffective against C. albicans in a challenge test at concentrations up to 16 times higher than the observed MIC values. When combining phenoxyethanol with either one of the allergenic preservatives diazolidinyl urea, MCI/MI or MI, the cosmetic cream was adequately preserved at concentrations well below the preservatives' MIC values as well as 10-20 times below the maximum permitted concentrations. By using combinations of preservatives, effective preservation can be achieved with lower concentrations of allergenic preservatives.

  8. MESERAN Calibration for Low Level Organic Residues

    SciTech Connect

    Benkovich, M.G.

    2004-04-08

    Precision cleaning studies done at Honeywell Federal Manufacturing & Technologies (FM&T), the Kansas City Plant (KCP), and at other locations within the Department of Energy (DOE) Weapons complex over the last 30 years have depended upon results from MESERAN Evaporative Rate Analysis for detecting low levels of organic contamination. The characterization of the surface being analyzed is carried out by depositing a Carbon-14 tagged radiochemical onto the test surface and monitoring the rate at which the radiochemical disappears from the surface with a Geiger-Mueller counter. In the past, the total number of counts over a 2-minute span have been used to judge whether a surface is contaminated or not and semi-quantitatively to what extent. This technique is very sensitive but has not enjoyed the broad acceptance of a purely quantitative analysis. The work on this project developed calibrations of various organic contaminants typically encountered in KCP operations. In addition, a new analysis method was developed to enhance the ability of MESERAN Analyzers to detect organic contamination and yield quantitative data in the microgram and nanogram levels.

  9. A model for a national low level waste program

    SciTech Connect

    Blankenhorn, James A

    2009-01-01

    A national program for the management of low level waste is essential to the success of environmental clean-up, decontamination and decommissioning, current operations and future missions. The value of a national program is recognized through procedural consistency and a shared set of resources. A national program requires a clear waste definition and an understanding of waste characteristics matched against available and proposed disposal options. A national program requires the development and implementation of standards and procedures for implementing the waste hierarchy, with a specitic emphasis on waste avoidance, minimization and recycling. It requires a common set of objectives for waste characterization based on the disposal facility's waste acceptance criteria, regulatory and license requirements and performance assessments. Finally, a national waste certification program is required to ensure compliance. To facilitate and enhance the national program, a centralized generator services organization, tasked with providing technical services to the generators on behalf of the national program, is necessary. These subject matter experts are the interface between the generating sites and the disposal facility(s). They provide an invaluable service to the generating organizations through their involvement in waste planning prior to waste generation and through championing implementation of the waste hierarchy. Through their interface, national treatment and transportation services are optimized and new business opportunities are identified. This national model is based on extensive experience in the development and on-going management of a national transuranic waste program and management of the national repository, the Waste Isolation Pilot Plant. The Low Level Program at the Savannah River Site also successfully developed and implemented the waste hierarchy, waste certification and waste generator services concepts presented below. The Savannah River Site

  10. Modeling of pilot's visual behavior for low-level flight

    NASA Astrophysics Data System (ADS)

    Schulte, Axel; Onken, Reiner

    1995-06-01

    Developers of synthetic vision systems for low-level flight simulators deal with the problem to decide which features to incorporate in order to achieve most realistic training conditions. This paper supports an approach to this problem on the basis of modeling the pilot's visual behavior. This approach is founded upon the basic requirement that the pilot's mechanisms of visual perception should be identical in simulated and real low-level flight. Flight simulator experiments with pilots were conducted for knowledge acquisition. During the experiments video material of a real low-level flight mission containing different situations was displayed to the pilot who was acting under a realistic mission assignment in a laboratory environment. Pilot's eye movements could be measured during the replay. The visual mechanisms were divided into rule based strategies for visual navigation, based on the preflight planning process, as opposed to skill based processes. The paper results in a model of the pilot's planning strategy of a visual fixing routine as part of the navigation task. The model is a knowledge based system based upon the fuzzy evaluation of terrain features in order to determine the landmarks used by pilots. It can be shown that a computer implementation of the model selects those features, which were preferred by trained pilots, too.

  11. Greater-confinement disposal of low-level radioactive wastes

    SciTech Connect

    Trevorrow, L.E.; Gilbert, T.L.; Luner, C.; Merry-Libby, P.A.; Meshkov, N.K.; Yu, C.

    1985-01-01

    Low-level radioactive wastes include a broad spectrum of wastes that have different radionuclide concentrations, half-lives, and physical and chemical properties. Standard shallow-land burial practice can provide adequate protection of public health and safety for most low-level wastes, but a small volume fraction (about 1%) containing most of the activity inventory (approx.90%) requires specific measures known as ''greater-confinement disposal'' (GCD). Different site characteristics and different waste characteristics - such as high radionuclide concentrations, long radionuclide half-lives, high radionuclide mobility, and physical or chemical characteristics that present exceptional hazards - lead to different GCD facility design requirements. Facility design alternatives considered for GCD include the augered shaft, deep trench, engineered structure, hydrofracture, improved waste form, and high-integrity container. Selection of an appropriate design must also consider the interplay between basic risk limits for protection of public health and safety, performance characteristics and objectives, costs, waste-acceptance criteria, waste characteristics, and site characteristics. This paper presents an overview of the factors that must be considered in planning the application of methods proposed for providing greater confinement of low-level wastes. 27 refs.

  12. Low level laser therapy on experimental myopathy

    PubMed Central

    Dávila, Soledad; Vignola, María Belén; Cremonezzi, David; Simes, Juan C.; Soriano, Fernando; Campana, Vilma R.

    2011-01-01

    Purpose: The aim of the present work was to study the effect of Helium-Neon (HeNe) and Gallium Arsenide (GaAs) laser upon nitric oxide (NO) plasma levels, an inflammatory biomarker associated with oxidative stress, in rats with experimental myopathy. These were evaluated through histological assessment. Materials and Methods: The groups studied were: (A) control (intact rats that received LLLT sham exposures), (B) rats with myopathy and sacrificed at 24 h later, (C) rats with myopathy and sacrificed 8 days later, (D) rats with myopathy and treated with HeNe laser, (E) rats with myopathy and treated with GaAs laser, (F) intact rats treated with HeNe laser and (G) intact rats treated with GaAs laser. Myopathy was induced by injecting 50μl of 1% carrageenan λ (type IV) in the left gastrocnemius muscle. Low Level Laser Therapy (LLLT) was applied with 9.5 J.cm−2 daily for 10 consecutive days with each laser. The determination of the NO was made by spectrophotometry. The muscles were stained with Hematoxylin-Eosin and examined by optic microscopy. Quantitative variables were statistically analyzed by the Fisher test, and categorical by applying Pearson's Chi Squared test at p <0.05 for all cases. Results: In groups B and C, NO was significantly increased compared to groups A, D, E, F and G (p<0.05). In group C, the percentage of area with inflammatory infiltration was significantly increased compared to the other groups (p<0.001). Conclusions: LLLT decreased plasma levels of NO in rats with experimental myopathies and significant muscle recovery. PMID:24155539

  13. Measuring the Magnetic Force on a Current-Carrying Conductor.

    ERIC Educational Resources Information Center

    Herreman, W.; Huysentruyt, R.

    1995-01-01

    Describes a fast and simple method for measuring the magnetic force acting on a current-carrying conductor using a digital balance. Discusses the influence of current intensity and wire length on the magnetic force on the conductor. (JRH)

  14. IGRIS for characterizing low-level radioactive waste

    SciTech Connect

    Peters, C.W.; Swanson, P.J.

    1993-03-01

    A recently developed neutron diagnostic probe system has the potential to noninvasively characterize low-level radioactive waste in bulk soil samples, containers such as 55-gallon barrels, and in pipes, valves, etc. The probe interrogates the target with a low-intensity beam of 14-MeV neutrons produced from the deuterium-tritium reaction in a specially designed sealed-tube neutron-generator (STNG) that incorporates an alpha detector to detect the alpha particle associated with each neutron. These neutrons interact with the nuclei in the target to produce inelastic-, capture-, and decay-gamma rays that are detected by gamma-ray detectors. Time-of-flight methods are used to separate the inelastic-gamma rays from other gamma rays and to determine the origin of each inelastic-gamma ray in three dimensions through Inelastic-Gamma Ray Imaging and Spectroscopy (IGRIS). The capture-gamma ray spectrum is measured simultaneously with the IGRIS measurements. The decay-gamma ray spectrum is measured with the STNG turned off. Laboratory proof-of-concept measurements were used to design prototype systems for Bulk Soil Assay, Barrel Inspection, and Decontamination and Decommissioning and to predict their minimum detectable levels for heavy toxic metals (As, Hg, Cr, Zn, Pb, Ni, and Cd), uranium and transuranics, gamma-ray emitters, and elements such as chlorine, which is found in PCBs and other pollutants. These systems are expected to be complementary and synergistic with other technologies used to characterize low-level radioactive waste.

  15. Status of low-level radioactive waste management in Korea

    SciTech Connect

    Lee, K.J.

    1993-03-01

    The Republic of Korea has accomplished dramatic economic growth over the past three decades; demand for electricity has rapidly grown more than 15% per year. Since the first nuclear power plant, Kori-1 [587 MWe, pressurized water reactor (PWR)], went into commercial operation in 1978, the nuclear power program has continuously expanded and played a key role in meeting the national electricity demand. Nowadays, Korea has nine nuclear power plants [eight PWRs and one Canadian natural uranium reactor (CANDU)] in operation with total generating capacity of 7,616 MWe. The nuclear share of total electrical capacity is about 36%; however, about 50% of actual electricity production is provided by these nine nuclear power plants. In addition, two PWRs are under construction, five units (three CANDUs and two PWRs) are under design, and three more CANDUs and eight more PWRs are planned to be completed by 2006. With this ambitious nuclear program, the total nuclear generating capacity will reach about 23,000 MWe and the nuclear share will be about 40% of the total generating capacity in the year 2006. In order to expand the nuclear power program this ambitiously, enormous amounts of work still have to be done. One major area is radioactive waste management. This paper reviews the status of low-level radioactive waste management in Korea. First, the current and future generation of low-level radioactive wastes are estimated. Also included are the status and plan for the construction of a repository for low-level radioactive wastes, which is one of the hot issues in Korea. Then, the nuclear regulatory system is briefly mentioned. Finally, the research and development activities for LLW management are briefly discussed.

  16. Issue briefs on low-level radioactive wastes

    SciTech Connect

    Not Available

    1981-01-01

    This report contains 4 Issue Briefs on low-level radioactive wastes. They are entitled: Handling, Packaging, and Transportation, Economics of LLW Management, Public Participation and Siting, and Low Level Waste Management.

  17. 26. CURRENT METERS WITH FOLDING SCALE (MEASURED IN INCHES) IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. CURRENT METERS WITH FOLDING SCALE (MEASURED IN INCHES) IN FOREGROUND: GURLEY MODEL NO. 665 AT CENTER, GURLEY MODEL NO. 625 'PYGMY' CURRENT METER AT LEFT, AND WES MINIATURE PRICE-TYPE CURRENT METER AT RIGHT. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  18. Using low levels of stochastic vestibular stimulation to improve locomotor stability

    PubMed Central

    Mulavara, Ajitkumar P.; Kofman, Igor S.; De Dios, Yiri E.; Miller, Chris; Peters, Brian T.; Goel, Rahul; Galvan-Garza, Raquel; Bloomberg, Jacob J.

    2015-01-01

    Low levels of bipolar binaural white noise based imperceptible stochastic electrical stimulation to the vestibular system (stochastic vestibular stimulation, SVS) have been shown to improve stability during balance tasks in normal, healthy subjects by facilitating enhanced information transfer using stochastic resonance (SR) principles. We hypothesize that detection of time-critical sub-threshold sensory signals using low levels of bipolar binaural SVS based on SR principles will help improve stability of walking during support surface perturbations. In the current study 13 healthy subjects were exposed to short continuous support surface perturbations for 60 s while walking on a treadmill and simultaneously viewing perceptually matched linear optic flow. Low levels of bipolar binaural white noise based SVS were applied to the vestibular organs. Multiple trials of the treadmill locomotion test were performed with stimulation current levels varying in the range of 0–1500 μA, randomized across trials. The results show that subjects significantly improved their walking stability during support surface perturbations at stimulation levels with peak amplitude predominantly in the range of 100–500 μA consistent with the SR phenomenon. Additionally, objective perceptual motion thresholds were measured separately as estimates of internal noise while subjects sat on a chair with their eyes closed and received 1 Hz bipolar binaural sinusoidal electrical stimuli. The optimal improvement in walking stability was achieved on average with peak stimulation amplitudes of approximately 35% of perceptual motion threshold. This study shows the effectiveness of using low imperceptible levels of SVS to improve dynamic stability during walking on a laterally oscillating treadmill via the SR phenomenon. PMID:26347619

  19. Using low levels of stochastic vestibular stimulation to improve locomotor stability.

    PubMed

    Mulavara, Ajitkumar P; Kofman, Igor S; De Dios, Yiri E; Miller, Chris; Peters, Brian T; Goel, Rahul; Galvan-Garza, Raquel; Bloomberg, Jacob J

    2015-01-01

    Low levels of bipolar binaural white noise based imperceptible stochastic electrical stimulation to the vestibular system (stochastic vestibular stimulation, SVS) have been shown to improve stability during balance tasks in normal, healthy subjects by facilitating enhanced information transfer using stochastic resonance (SR) principles. We hypothesize that detection of time-critical sub-threshold sensory signals using low levels of bipolar binaural SVS based on SR principles will help improve stability of walking during support surface perturbations. In the current study 13 healthy subjects were exposed to short continuous support surface perturbations for 60 s while walking on a treadmill and simultaneously viewing perceptually matched linear optic flow. Low levels of bipolar binaural white noise based SVS were applied to the vestibular organs. Multiple trials of the treadmill locomotion test were performed with stimulation current levels varying in the range of 0-1500 μA, randomized across trials. The results show that subjects significantly improved their walking stability during support surface perturbations at stimulation levels with peak amplitude predominantly in the range of 100-500 μA consistent with the SR phenomenon. Additionally, objective perceptual motion thresholds were measured separately as estimates of internal noise while subjects sat on a chair with their eyes closed and received 1 Hz bipolar binaural sinusoidal electrical stimuli. The optimal improvement in walking stability was achieved on average with peak stimulation amplitudes of approximately 35% of perceptual motion threshold. This study shows the effectiveness of using low imperceptible levels of SVS to improve dynamic stability during walking on a laterally oscillating treadmill via the SR phenomenon. PMID:26347619

  20. Greater-than-Class C low-level waste characterization. Appendix F: Greater-than-Class C low-level radioactive waste light water reactor projections

    SciTech Connect

    Tuite, P.; Tuite, K.; Levin, A.; O`Kelley, M.

    1991-08-01

    This study characterizes potential greater-than-Class C low-level radioactive waste streams, estimates the amounts of waste generated, and estimates their radionuclide content and distribution. Several types of low-level radioactive wastes produced by light water reactors were identified in an earlier study as being potential greater-than-Class C low-level waste, including specific activated metal components and certain process wastes in the form of cartridge filters and decontamination resins. Light water reactor operating parameters and current management practices at operating plants were reviewed and used to estimate the amounts of potential greater-than-Class C low-level waste generated per fuel cycle. The amounts of routinely generated activated metal components and process waste were estimated as a function of fuel cycle. Component-specific radionuclide content and distribution was calculated for activated metals components. Empirical data from actual low-level radioactive waste streams were used to estimate radionuclide content and distribution for process wastes. The greater-than-Class C low-level waste volumes that could be generated through plant closure were also estimated, along with volumes and activities for potential greater-than-Class C activated metals generated at decommissioning.

  1. UCB current detector experiment on Swedish auroral payloads. [ionospheric current and plasma flow measurements

    NASA Technical Reports Server (NTRS)

    Mozer, F.

    1974-01-01

    A split Langmuir probe has been developed to make in situ measurements of ionospheric current density and plasma bulk flow. The probe consists of two conducting elements that are separated by a thin insulator that shield each other over a 2 pi solid angle, and that are simultaneously swept from negative to positive with respect to the plasma. By measuring the current to each plate and the difference current between plates, information is obtained on the plasma's current density, bulk flow, electron temperature, and density. The instrument was successfully flown twice on sounding rockets into auroral events. Measurement data indicate that the total auroral current configuration is composed of several alternating east and west electrojets associated with several alternating up and down Birkeland currents.

  2. A study of eddy current measurement (1986-1987)

    SciTech Connect

    Ramachandran, R.S.; Armstrong, K.P.

    1989-06-22

    A study was conducted in 1986 to evaluate a modified eddy current system for measuring copper thickness on Kapton. Results showed a measurement error of 0.42 {mu}in. for a thickness range of 165 to 170 {mu}in. and a measurement variability of 3.2 {mu}in.

  3. Precision Absolute Beam Current Measurement of Low Power Electron Beam

    SciTech Connect

    Ali, M. M.; Bevins, M. E.; Degtiarenko, P.; Freyberger, A.; Krafft, G. A.

    2012-11-01

    Precise measurements of low power CW electron beam current for the Jefferson Lab Nuclear Physics program have been performed using a Tungsten calorimeter. This paper describes the rationale for the choice of the calorimeter technique, as well as the design and calibration of the device. The calorimeter is in use presently to provide a 1% absolute current measurement of CW electron beam with 50 to 500 nA of average beam current and 1-3 GeV beam energy. Results from these recent measurements will also be presented.

  4. Vessel eddy current measurement for the National Spherical Torus Experiment

    SciTech Connect

    Gates, D.A.; Menard, J.E.; Marsala, R.J.

    2004-12-01

    A simple analog circuit that measures the National Spherical Torus Experiment (NSTX) axisymmetric eddy current distribution has been designed and constructed. It is based on simple circuit model of the NSTX vacuum vessel that was calibrated using a special axisymmetric eddy current code which was written so that accuracy was maintained in the vicinity of the current filaments [J. Menard, J. Fusion Tech. (to be published)]. The measurement and the model have been benchmarked against data from numerous vacuum shots and they are in excellent agreement. This is an important measurement that helps give more accurate equilibrium reconstructions.

  5. Coherent radar measurement of ocean currents from geostationary orbit

    NASA Technical Reports Server (NTRS)

    Mcintosh, R. E.

    1989-01-01

    A coherent HF radar system developed by Barrick has successfully measured ocean surface currents near shore. This innovative system, called CODAR, can map the current vector for coastal areas as large as 10,000 sq km. CODAR's range is limited owing to the strong attenuation suffered by HF ground waves. An alternate technique was proposed by Schuler, in which the cross-product power spectrum of two (different frequency) microwave signals is processed. The frequency of the resonant peak corresponds close by to the Doppler shift of an ocean gravity wave traveling toward the radar at the phase velocity, v(sub p). The slight difference between the frequency of the measured resonant delta K peak and the Doppler frequency shift caused by the motion of the gravity wave is attributed to be the current velocity in the pointing direction of the radar. The Microwave Remote Sensing Laboratory (MIRSL) has considered the feasibility of using this technique to measure ocean surface currents from geostationary satellite platforms. Problems are discussed that must be overcome if a satellite current measurement system is to be realized. MIRSL research activities that address some of these problem areas are discussed. Current measurements are presented that were made using a specially-designed C-Band, step-frequency delta K radar. These measurements suggest that progress is being achieved in detecting ocean surface current motion for a wide variety of ocean surface conditions.

  6. Disposal of low-level and mixed low-level radioactive waste during 1990

    SciTech Connect

    Not Available

    1993-08-01

    Isotopic inventories and other data are presented for low-level radioactive waste (LLW) and mixed LLW disposed (and occasionally stored) during calendar year 1990 at commercial disposal facilities and Department of Energy (DOE) sites. Detailed isotopic information is presented for the three commercial disposal facilities located near Barnwell, SC, Richland, WA, and Beatty, NV. Less information is presented for the Envirocare disposal facility located near Clive, UT, and for LLW stored during 1990 at the West Valley site. DOE disposal information is included for the Savannah River Site (including the saltstone facility), Nevada Test Site, Los Alamos National Laboratory, Idaho National Engineering Laboratory, Hanford Site, Y-12 Site, and Oak Ridge National Laboratory. Summary information is presented about stored DOE LLW. Suggestions are made about improving LLW disposal data.

  7. Electrolytic decontamination of metal low level waste (LLW) and mixed low level waste (MLLW)

    SciTech Connect

    1998-11-01

    Metal objects resulting from ER activities were decontaminated using electrolytic methods. The project involved about 500 kg of ballistic test projectiles, 23 augers and drill heads, and 50 pieces of shrapnel containing lead. All objects were free-released and either reclaimed as scrap metal or reused. Electrolytic decontamination was proven to be an effective method to decontaminate metal waste objects to free-release standards. A cost analysis showed the process to be economical, especially when applied to decontamination of mixed waste, TRU waste, or when the recovered materials could be reused or recycled. The cost of decontamination of scrap iron is approximately equal to the cost of its land disposal as low level waste.

  8. A concept for measuring currents from geostationary satellites

    NASA Astrophysics Data System (ADS)

    Popstefanija, I.; McIntosh, R. E.

    The measurement of ocean surface currents may be possible from geostationary satellites in space using coherent dual-frequency radars. However, feasibility of this concept depends on how reliable a resonant 'Delta K peak' is observed when the cross-product power spectrum of the two microwave signals is formed. Experimental results obtained with the University of Massachusetts Stepped-Frequency Delta K radar. The radar is a frequency-agile radar, which rapidly switches between pairs of signal frequencies. Data obtained at a North Truro, Massachusetts, test site indicates that the radar can measure tidal surface currents as well as wind-driven currents. When surface winds are steady, periodic tidal current variations are observed. However, when the wind changes speed or direction there are corresponding fluctuations in the measured currents.

  9. 33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT WES IN 1932 BY CARL E. BENTZEL. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  10. Critical Current Measurements in Commercial Tapes, Coils, and Magnets.

    NASA Astrophysics Data System (ADS)

    Gubser, D. U.; Soulen, R. J., Jr.; Fuller-Mora, W. W.; Francavilla, T. L.

    1996-03-01

    We have measured a number of tapes, coils, and magnets produced by commercial vendors and determined their properties as functions of magnetic field and temperature. The tapes were measured at the National High Magnetic Field Laboratory in magnetic fields to 20 tesla and at temperatures of 4.2 K, 27 K, 65 K, and 77 K. For the tapes we report critical currents and current-voltage characteristics. Six inch diameter coils were measured at NRL in zero magnetic field. Critical currents, current-voltage characteristics, and reliability studies are reported for the coils. Larger 10 inch diameter coils, which are to be used in a 200 hp superconducting motor, were also measured and results will be presented. The talk will also review the status of the most recent tests of the superconducting motor.

  11. Junction Temperature Measurement of IGBTs Using Short Circuit Current

    SciTech Connect

    Wang, Fei; Xu, Zhuxian; Ning, Puqi

    2012-01-01

    In this paper, a method is proposed to measure the junction temperatures of IGBT discrete devices and modules using short circuit current. Experimental results show that the short circuit current has good sensitivity, linearity and selectivity, which is suitable to be used as temperature sensitive electrical parameters (TSEP). Test circuit and hardware design are proposed for junction temperature measurement in single phase and three phase convertes. By connecting a temperature measurement unit to the converter and giving a short circuit pulse, the IGBT junction temperature can be measured.

  12. A simple electrometer for measuring small photoelectric currents

    NASA Technical Reports Server (NTRS)

    1969-01-01

    Quartz-fiber direct-indicating pocket dosimeter is a small-current integrating electrometer. By attaching the photocathode to the quartz fiber terminal and the photoelectron collector to the barrel of the dosimeter and by charging the device to 150 V, a small-current measuring device can be achieved.

  13. Another Nulling Hall-Effect Current-Measuring Circuit

    NASA Technical Reports Server (NTRS)

    Thibodeau, Phillip E.; Sullender, Craig C.

    1993-01-01

    Lightweight, low-power circuit provides noncontact measurement of alternating or direct current of many ampheres in main conductor. Advantages of circuit over other nulling Hall-effect current-measuring circuits is stability and accuracy increased by putting both analog-to-digital and digital-to-analog converters in nulling feedback loop. Converters and rest of circuit designed for operation at sampling rate of 100 kHz, but rate changed to alter time or frequency response of circuit.

  14. A Fiber-Optic Aircraft Lightning Current Measurement Sensor

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

    2013-01-01

    A fiber-optic current sensor based on the Faraday Effect is developed for aircraft installations. It can measure total lightning current amplitudes and waveforms, including continuing current. Additional benefits include being small, lightweight, non-conducting, safe from electromagnetic interference, and free of hysteresis and saturation. The Faraday Effect causes light polarization to rotate in presence of magnetic field in the direction of light propagation. Measuring the total induced light polarization change yields the total current enclosed. The system operates at 1310nm laser wavelength and can measure approximately 300 A - 300 kA, a 60 dB range. A reflective polarimetric scheme is used, where the light polarization change is measured after a round-trip propagation through the fiber. A two-detector setup measures the two orthogonal polarizations for noise subtraction and improved dynamic range. The current response curve is non-linear and requires a simple spline-fit correction. Effects of high current were achieved in laboratory using combinations of multiple fiber and wire loops. Good result comparisons against reference sensors were achieved up to 300 kA. Accurate measurements on a simulated aircraft fuselage and an internal structure illustrate capabilities that maybe difficult with traditional sensors. Also tested at a commercial lightning test facility from 20 kA to 200 kA, accuracy within 3-10% was achieved even with non-optimum setups.

  15. Measurements of current penetration during PDX discharge start-up

    SciTech Connect

    Meyerhofer, D.D.; Goldston, R.J.; Kaita, R.; Cavallo, A.; Grek, B.; Johnson, D.; McCune, D.C.; McGuire, K.; White, R.B.

    1984-11-01

    The current penetration phase of PDX discharges is examined. The Fast Ion Diagnostic Experiment has been used to measure the temporal evolution of the central q (r/a < 0.4), and to show the effect of magnetic perturbations on fast ions. During plasma current penetration, a series of magnetic perturbations was observed in the plasma. If the current was rising rapidly, the perturbations were accompanied by increases in ..beta../sub theta/ + l/sub i//2 and decreases in the loop voltage, suggesting a rapid penetration of the plasma current. When the plasma current was rising slowly, a series of minor disruptions occurred. These were accompanied by decreases in ..beta../sub theta/ + l/sub i//2 and the loop voltage, and increases in the plasma current. During this phase, current penetration may be enhanced by the change in the resistivity profile which accompanies the disruption.

  16. Effects of high vs low-level radiation exposure

    SciTech Connect

    Bond, V.P.

    1983-01-01

    In order to appreciate adequately the various possible effects of radiation, particularly from high-level vs low-level radiation exposure (HLRE, vs LLRE), it is necessary to understand the substantial differences between (a) exposure as used in exposure-incidence curves, which are always initially linear and without threshold, and (b) dose as used in dose-response curves, which always have a threshold, above which the function is curvilinear with increasing slope. The differences are discussed first in terms of generally familiar nonradiation situations involving dose vs exposure, and then specifically in terms of exposure to radiation, vs a dose of radiation. Examples are given of relevant biomedical findings illustrating that, while dose can be used with HLRE, it is inappropriate and misleading the LLRE where exposure is the conceptually correct measure of the amount of radiation involved.

  17. Summertime Low-Level Jets over the Great Plains

    SciTech Connect

    Stensrud, D.J.

    1996-04-01

    The sky over the southern Great Plains Cloud and Atmospheric Radiation Testbed (CART) site of the Atmospheric Radiation Measurement (ARM) Program during the predawn and early morning hours often is partially obstructed by stratocumulus, stratus fractus, or cumulus fractus that are moving rapidly to the north, even through the surface winds are weak. This cloud movement is evidence of the low-level jet (LLJ), a wind speed maximum that occurs in the lowest few kilometers of the atmosphere. Owing to the wide spacing between upper-air sounding sites and the relatively infrequent sounding launches, LLJ evolution has been difficult to observe adequately, even though the effects of LLJs on moisture flux into North America are large. Model simulation of the LLJ is described.

  18. Effect of interstitial low level laser stimulation in skin density

    NASA Astrophysics Data System (ADS)

    Jang, Seulki; Ha, Myungjin; Lee, Sangyeob; Yu, Sungkon; Park, Jihoon; Radfar, Edalat; Hwang, Dong Hyun; Lee, Han A.; Kim, Hansung; Jung, Byungjo

    2016-03-01

    As the interest in skin was increased, number of studies on skin care also have been increased. The reduction of skin density is one of the symptoms of skin aging. It reduces elasticity of skin and becomes the reason of wrinkle formation. Low level laser therapy (LLLT) has been suggested as one of the effective therapeutic methods for skin aging as in hasten to change skin density. This study presents the effect of a minimally invasive laser needle system (MILNS) (wavelength: 660nm, power: 20mW) in skin density. Rabbits were divided into three groups. Group 1 didn't receive any laser stimulation as a control group. Group 2 and 3 as test groups were exposed to MILNS with energy of 8J and 6J on rabbits' dorsal side once a week, respectively. Skin density of rabbits was measured every 12 hours by using an ultrasound skin scanner.

  19. Low Level Laser Therapy: laser radiation absorption in biological tissues

    NASA Astrophysics Data System (ADS)

    Di Giacomo, Paola; Orlando, Stefano; Dell'Ariccia, Marco; Brandimarte, Bruno

    2013-07-01

    In this paper we report the results of an experimental study in which we have measured the transmitted laser radiation through dead biological tissues of various animals (chicken, adult and young bovine, pig) in order to evaluate the maximum thickness through which the power density could still produce a reparative cellular effect. In our experiments we have utilized a pulsed laser IRL1 ISO model (based on an infrared diode GaAs, λ=904 nm) produced by BIOMEDICA s.r.l. commonly used in Low Level Laser Therapy. Some of the laser characteristics have been accurately studied and reported in this paper. The transmission results suggest that even with tissue thicknesses of several centimeters the power density is still sufficient to produce a cell reparative effect.

  20. Leaching studies of low-level radioactive waste forms

    SciTech Connect

    Dayal, R.; Arora, H.; Milian, L.; Clinton, J.

    1985-01-01

    A research program has been underway at the Brookhaven National Laboratory to investigate the release of radionuclides from low-level waste forms under laboratory conditions. This paper describes the leaching behavior of Cs-137 from two major low-level waste streams, that is, ion exchange bead resin and boric acid concentrate, solidified in Portland cement. The resultant leach data are employed to evaluate and predict the release behavior of Cs-137 from low-level waste forms under field burial conditions.

  1. Low-Level Waste (LLW) forum meeting report

    SciTech Connect

    1995-12-31

    The Low-Level Radioactive Waste Forum (LLW Forum) is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  2. Fiber-Optic Sensor for Aircraft Lightning Current Measurement

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George G.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

    2012-01-01

    An electric current sensor based on Faraday rotation effect in optical fiber was developed for measuring aircraft lightning current. Compared to traditional sensors, the design has many advantages including the ability to measure total current and to conform to structure geometries. The sensor is also small, light weight, non-conducting, safe from interference, and free of hysteresis and saturation. Potential applications include characterization of lightning current waveforms, parameters and paths, and providing environmental data for aircraft certifications. In an optical fiber as the sensing medium, light polarization rotates when exposed to a magnetic field in the direction of light propagation. By forming closed fiber loops around a conductor and applying Ampere s law, measuring the total light rotation yields the enclosed current. A reflective polarimetric scheme is used, where polarization change is measured after the polarized light travels round-trip through the sensing fiber. The sensor system was evaluated measuring rocket-triggered lightning over the 2011 summer. Early results compared very well against a reference current shunt resistor, demonstrating the sensor s accuracy and feasibility in a lightning environment. While later comparisons show gradually increasing amplitude deviations for an undetermined cause, the overall waveforms still compared very well.

  3. Fiber-Optic Sensor for Aircraft Lightning Current Measurement

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George G.; Mata, Carlos T.; Mata,Angel G.; Snyder, Gary P.

    2012-01-01

    An electric current sensor based on Faraday rotation effect in optical fiber was developed for measuring aircraft lightning current. Compared to traditional sensors, the design has many advantages including the ability to measure total current and to conform to structure geometries. The sensor is also small, light weight, non-conducting, safe from interference, and free of hysteresis and saturation. Potential applications include characterization of lightning current waveforms, parameters and paths, and providing environmental data for aircraft certifications. In an optical fiber as the sensing medium, light polarization rotates when exposed to a magnetic field in the direction of light propagation. By forming closed fiber loops around a conductor and applying Ampere s law, measuring the total light rotation yields the enclosed current. A reflective polarimetric scheme is used, where polarization change is measured after the polarized light travels round-trip through the sensing fiber. The sensor system was evaluated measuring rocket-triggered lightning over the 2011 summer. Early results compared very well against a reference current shunt resistor, demonstrating the sensor's accuracy and feasibility in a lightning environment. While later comparisons show gradually increasing amplitude deviations for an undetermined cause, the overall waveforms still compared very well.

  4. On remote measurements of lightning return stroke peak currents

    NASA Astrophysics Data System (ADS)

    Mallick, S.; Rakov, V. A.; Tsalikis, D.; Nag, A.; Biagi, C.; Hill, D.; Jordan, D. M.; Uman, M. A.; Cramer, J. A.

    2014-01-01

    Return-stroke peak current is one of the most important measures of lightning intensity needed in different areas of atmospheric electricity research. It can be estimated from the corresponding electric or magnetic radiation field peak. Electric fields of 89 strokes in lightning flashes triggered using the rocket-and-wire technique at Camp Blanding (CB), Florida, were recorded at the Lightning Observatory in Gainesville, about 45 km from the lightning channel. Lightning return-stroke peak currents were estimated from the measured electric field peaks using the empirical formula of Rakov et al. (1992) and the field-to-current conversion equation based on the transmission line model (Uman and McLain, 1969). These estimates, along with peak currents reported by the U.S. National Lightning Detection Network (NLDN), were compared with the ground-truth data, currents directly measured at the lightning channel base. The empirical formula, based on data for 28 triggered-lightning strokes acquired at the Kennedy Space Center (KSC), tends to overestimate peak currents, whereas the NLDN-reported peak currents are on average underestimates. The field-to-current conversion equation based on the transmission line model gives the best match with directly measured peak currents for return-stroke speeds between c/2 and 2c/3 (1.5 and 2 × 108 m/s, respectively). Possible reasons for the discrepancy in the peak current estimates from the empirical formula and the ground-truth data include an error in the field calibration factor, difference in the typical return-stroke speeds at CB and at the KSC (considered here to be the most likely reason), and limited sample sizes, particularly for the KSC data. A new empirical formula, I = - 0.66-0.028rE, based on data for 89 strokes in lightning flashes triggered at CB, is derived.

  5. Note: atmospheric point discharge current measurements using a temperature-compensated logarithmic current amplifier.

    PubMed

    Marlton, G J; Harrison, R G; Nicoll, K A

    2013-06-01

    Measurements of atmospheric corona currents have been made for over 100 years to indicate the atmospheric electric field. Corona currents vary substantially, in polarity and in magnitude. The instrument described here uses a sharp point sensor connected to a temperature compensated bi-polar logarithmic current amplifier. Calibrations over a range of currents from ±10 fA to ±3 μA and across ±20 °C show it has an excellent logarithmic response over six orders of magnitude from 1 pA to 1 μA in both polarities for the range of atmospheric temperatures likely to be encountered in the southern UK. Comparison with atmospheric electric field measurements during disturbed weather confirms that bipolar electric fields induce corona currents of corresponding sign, with magnitudes ~0.5 μA. PMID:23822390

  6. Measuring gravity currents in the Chicago River, Chicago, Illinois

    USGS Publications Warehouse

    Oberg, K.A.; Czuba, J.A.; Johnson, K.K.

    2008-01-01

    Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current profilers (ADCP) can be used to detect and characterize gravity currents in the field. In order to better understand the formation and evolution of these gravity currents, the U.S. Geological Survey (USGS) has installed ADCPs and other instruments to continuously measure gravity currents in the Chicago River and the North Branch Chicago River. These instruments include stage sensors, thermistor strings, and both upward-looking and horizontal ADCPs. Data loggers and computers installed at gaging stations along the river are used to collect data from these instruments and transmit them to USGS offices. ?? 2008 IEEE.

  7. Identification of Low-level Point Radioactive Sources using a sensor network

    SciTech Connect

    Chin, J. C.; Rao, Nageswara S.; Yao, David K. Y.; Shankar, Mallikarjun; Yang, Yong; Hou, J. C.; Srivathsan, Sri; Iyengar, S. Sitharama

    2010-09-01

    Identification of a low-level point radioactive source amidst background radiation is achieved by a network of radiation sensors using a two-step approach. Based on measurements from three or more sensors, a geometric difference triangulation method or an N-sensor localization method is used to estimate the location and strength of the source. Then a sequential probability ratio test based on current measurements and estimated parameters is employed to finally decide: (1) the presence of a source with the estimated parameters, or (2) the absence of the source, or (3) the insufficiency of measurements to make a decision. This method achieves specified levels of false alarm and missed detection probabilities, while ensuring a close-to-minimal number of measurements for reaching a decision. This method minimizes the ghost-source problem of current estimation methods, and achieves a lower false alarm rate compared with current detection methods. This method is tested and demonstrated using: (1) simulations, and (2) a test-bed that utilizes the scaling properties of point radioactive sources to emulate high intensity ones that cannot be easily and safely handled in laboratory experiments.

  8. Current Measurements and Overwash Monitoring Using Tilt Current Meters in Three Coastal Environments

    NASA Astrophysics Data System (ADS)

    Lowell, N. S.; Sherwood, C. R.; Decarlo, T. M.; Grant, J. R.

    2014-12-01

    Tilt Current Meters (TCMs) provide accurate, cost effective measurements of near-bottom current velocities. Many studies in coastal environments require current measurements, which are frequently made with Acoustic Doppler Profilers (ADPs). ADPs are expensive, however, and may not be suitable for locations where there is significant risk of damage, loss, or theft or where a large spatial array of measurements is required. TCMs, by contrast, are smaller, less expensive, and easier to deploy. This study tested TCMs in three sites to determine their suitability for use in research applications. TCMs are based on the drag-tilt principle, where the instrument tilts in response to current. The meter consists of a buoyant float with an onboard accelerometer, three-axis tilt sensor, three-axis magnetometer (compass), and a data logger. Current measurements are derived by post processing the tilt and compass values and converting them to velocity using empirical calibration data. Large data-storage capacity (4 GB) and low power requirements allow long deployments (many months) at high sample rates (16 Hz). We demonstrate the utility of TCM current measurements on a reef at Dongsha Atoll in the South China Sea, and in Vineyard Sound off Cape Cod, where the TCM performance was evaluated against ADP measurements. We have also used the TCM to record waves during an overwash event on a Cape Cod barrier beach during a winter storm. The TCM recorded waves as they came through the overwash channel, and the data were in agreement with the water-level record used as a reference. These tests demonstrate that TCMs may be used in a variety of near shore environments and have the potential to significantly increase the density of meters in future studies were current measurements are required.

  9. Study of a fibre optics current sensor for the measurement of plasma current in ITER

    NASA Astrophysics Data System (ADS)

    Wuilpart, Marc; Vanus, Benoit; Andrasan, Alina; Gusarov, Andrei; Moreau, Philippe; Mégret, Patrice

    2016-05-01

    In this article, we study the feasibility of using a fibre-optics current sensor (FOCS) for the measurement of plasma current in the future fusion reactor ITER. The sensor is based on a classical FOCS interrogator involving the measurement of the state of polarization rotation undergone by the light in presence of a magnetic field (Faraday effect) in an optical fibre surrounding the current and terminated by a Faraday mirror. We considered a uniformly spun optical fibre as the sensing element and we used the Stokes formalism to simulate the sensor. The objective of the simulations is to quantify the ratio LB/SP (beat length over the spun period of the spun fibre) enabling a measurement error in agreement with the ITER specifications. The simulator takes into account the temperature variations undergone by the measurement system under ITER operation. The simulation work showed that a LB/SP ratio of 19.2 is adequate.

  10. The evaluation of rock permeability with streaming current measurements

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Hu, Hengshan; Guan, Wei

    2016-09-01

    Rock permeability is an important parameter for the formation evaluation. In this paper, a new method with streaming current is proposed to determine the sample permeability based on the electrokinetic effects, and is proved by the experimental measurements. Corresponding to this method, we have designed an experimental setup and a test system, then performed the streaming current (potential) and electro-osmosis pressure experiments with 23 sandstone samples at 0.05 mol l-1 NaCl solution. The streaming current (potential) coefficient and electro-osmosis pressure coefficient are obtained, respectively, with the experimental data at low frequencies with AC lock-in technique. The electrokinetic permeabilities are further calculated with these coefficients. The results are consistent well with the gas permeability measured with Darcy's law, which verifies the current method for estimating rock permeability. Our measurements are also analysed and compared with previous measurements. The results indicate that our method can reflect the essence of electrokinetic effects better and simplify the electrokinetic measurements as well. In addition, we discuss the influences of experimental artefacts (core holder and confining pressure installation) on the electrokinetic data. The results show that the trough phenomenon, appeared in frequency curves of streaming current (potential) coefficients, is induced by the resonance of the core-holder/vibrator system. This is important for the design of electrokinetic setup and the analysis of low-frequency response of the electrokinetic coupling coefficients.

  11. The evaluation of rock permeability with streaming current measurements

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Hu, Hengshan; Guan, Wei

    2016-06-01

    Rock permeability is an important parameter for the formation evaluation. In this paper, a new method with streaming current is proposed to determine the sample permeability based on the electrokinetic effects, and is proved by the experimental measurements. Corresponding to this method, we have designed an experimental setup and a test system, then performed the streaming current (potential) and electroosmosis pressure experiments with 23 sandstone samples at 0.05 mol/l NaCl solution. The streaming current (potential) coefficient and electroosmosis pressure coefficient are obtained respectively with the experimental data at low frequencies with AC lock-in technique. The electrokinetic permeabilities are further calculated with these coefficients. The results are consistent well with the gas permeability measured with Darcy's law, which verifies the current method for estimating rock permeability. Our measurements are also analyzed and compared with previous measurements. The results indicate that our method can reflect the essence of electrokinetic effects better and simplify the electrokinetic measurements as well. In addition, we discuss the influences of experimental artefacts (core-holder and confining pressure installation) on the electrokinetic data. The results show that the trough phenomenon, appeared in frequency curves of streaming current (potential) coefficients, is induced by the resonance of the core-holder/vibrator system. This is important for the design of electrokinetic setup and the analysis of low frequency response of the electrokinetic coupling coefficients.

  12. Velocity Profile Normalization of Field-Measured Turbidity Currents

    NASA Astrophysics Data System (ADS)

    Xu, J.

    2009-05-01

    Multiple occurrences of turbidity currents were observed in moored-ADCP measurements in Monterey (2002/03) and Hueneme (2007/08) submarine canyons, California. These turbidity currents, almost all of which were supercritical (densimetric Froude number greater than unity), lasted for hours and obtained a maximum speed of greater than 200 cm/s. The layer-averaged velocity of the turbidity currents varied from 100+ cm/s at the onset of the turbidity currents to 20+ cm/s toward the end of the events. The thickness of the turbidity currents tended to increase from 10 to 40 m over an event. Empirical functions, obtained from laboratory experiments whose spatial and time scales are two to three orders of magnitude smaller than the field measurements [e.g. Altinakar, Graf, and Hopfinger, 1996, Flow structure in turbidity currents, Journal of Hydraulic Research, 34(5):713-718], were found to represent the field data fairly well. However, the best similarity collapse of the turbidity current velocity profiles was obtained when the streamwise velocity was normalized by the layer-averaged velocity and the elevation was normalized by the turbidity current thickness. This normalization scheme can be generalized to the same empirical function y = exp (-α xm) for the jet region above the velocity maximum.

  13. Impact of Low-level Jet on Regional Ozone

    NASA Astrophysics Data System (ADS)

    Liu, F.

    2011-12-01

    During spring and summer seasons, the frequent occurrences of nocturnal low-level jet (LLJ) over Great Plains region of the United States are widely recognized. As an important element of the low-level atmospheric circulation this LLJ effectively transports water vapor from the Gulf of Mexico, which in turn affects the development of server weather over the central United States. The LLJ has long been known to be conducive to summer rainfall and widespread flooding over the Great Plains of North America. The LLJ transports more than just moisture. Ozone episodes occur mainly during summer and are influenced by regional transport. Little is known, however,about the interrelation between the Great Plains LLJ and regional ozone transport. In this study, analysis of observational data during 1993-2006 has shown strong influence of the Great Plains LLJ on local and regional ozone distributions. Hourly ozone measurements from Air Quality System (AQS) are compared with wind fields at 850 hPa from the NCEP North American Regional Reanalysis (NARR). It is demonstrated that the low ozone concentrations over Texas in late spring and summer are identified with large LLJ transport of clean marine air mass from the Gulf of Mexico. Significant negative correlations exist between daily ozone concentration and LLJ index (Figure 1), suggesting that lower ozone over Texas is associated with stronger LLJ. On the other hand, positive correlations occur in the Midwest and Northeast, indicating the important role of regional transport of ozone and precursors along the pathway by the wind circulation accompanying the LLJ. In addition, the LLJ is significantly correlated with northerly flows in the eastern Pacific Ocean and the adjacent coast. This relationship explains the coexistence of low ozone concentrations in Texas and southwestern U.S during summer, both attributed to the inland transport of clean marine air. These observed ozone-LLJ patterns are well simulated by the regional CMM5

  14. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1994-08-01

    This report presents a history of commercial low-level radioactive waste disposal in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the last decade to ensure the safe disposal of low-level radioactive waste in the 1990s and beyond. These steps include the issuance of comprehensive State and Federal regulations governing the disposal of low-level radioactive waste, and the enactment of Federal laws making States responsible for the disposal of such waste generated within their borders.

  15. Responses to the low-level-radiation controversy

    SciTech Connect

    Bond, V.P.

    1981-10-07

    Some data sets dealing with the hazards of low-level radiation are discussed. It is concluded that none of these reports, individually or collectively, changes appreciably or even significantly the evaluations of possible low-level radiation effects that have been made by several authoritative national and international groups. (ACR)

  16. Lightning Current Measurement with Fiber-Optic Sensor

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

    2014-01-01

    A fiber-optic current sensor is successfully developed with many potential applications for electric current measurement. Originally developed for in-flight lightning measurement, the sensor utilizes Faraday Effect in an optical fiber. The Faraday Effect causes linear light polarization in a fiber to rotate when the fiber is exposed to a magnetic field. The polarization change is detected using a reflective polarimetric scheme. Forming fiber loops and applying Ampere's law, measuring the total light rotation results in the determination of the total current enclosed. The sensor is conformable to complex structure geometry. It is also non-conductive and immune to electromagnetic interference, saturation or hysteresis. Installation is non-intrusive, and the sensor can be safely routed through flammable areas. Two similar sensor systems are described in this paper. The first system operates at 1310nm laser wavelength and is capable of measuring approximately 300 A - 300 kA, a 60 dB range. Laboratory validation results of aircraft lighting direct and in-direct effect current amplitudes are reported for this sensor. The second system operates at 1550nm wavelength and can measure about 400 A - 400 kA. Triggered-lightning measurement data are presented for this system. Good results are achieved in all cases.

  17. Application of Low level Lasers in Dentistry (Endodontic)

    PubMed Central

    Asnaashari, Mohammad; Safavi, Nassimeh

    2013-01-01

    Low level lasers, cold or soft lasers: These lasers do not produce thermal effects on tissues and induce photoreactions in cells through light stimulation which is called photobiostimulation. Power of these lasers is usually under 250mW. The main point differentiating low level lasers and high power ones is the activation of photochemical reactions without heat formation. The most important factor to achieve this light characteristic in lasers is not their power, but their power density for each surfa ceunit (i.e cm2). Density lower than 670mW/cm2, can induce the stimulatory effects of low level lasers without thermal effects. Low level lasers (therapeutic) used today as treatment adjunctive devices in medicine and dentistry. Numerous studies have been performed on the applications of low level lasers in patient pain reduction. Mechanisms of pain reduction with therapeutic lasers and their application are expressed, and the studies realized in this field are presented. PMID:25606308

  18. The Role of Low-Level Laser in Periodontal Surgeries

    PubMed Central

    Sobouti, Farhad; Khatami, Maziar; Heydari, Mohaddase; Barati, Maryam

    2015-01-01

    Treatment protocols with low-level Laser (also called ‘soft laser therapy) have been used in health care systems for more than three decades. Bearing in mind the suitable sub-cellular absorption and the cellular-vascular impacts, low-level laser may be a treatment of choice for soft tissues. Low-level lasers have played crucial and colorful roles in performing periodontal surgeries. Their anti-inflammatory and painless effects have been variously reported in in-vitro studies. In this present review article, searches have been made in Pub Med, Google Scholar, and Science Direct, focusing on the studies which included low-level lasers, flap-periodontal surgeries, gingivectomy, and periodontal graft. The present study has sought to review the cellular impacts of low-level lasers and its role on reducing pain and inflammation following soft tissue surgical treatments. PMID:25987968

  19. Effective shielding to measure beam current from an ion source

    SciTech Connect

    Bayle, H.; Delferrière, O.; Gobin, R.; Harrault, F.; Marroncle, J.; Senée, F.; Simon, C.; Tuske, O.

    2014-02-15

    To avoid saturation, beam current transformers must be shielded from solenoid, quad, and RFQ high stray fields. Good understanding of field distribution, shielding materials, and techniques is required. Space availability imposes compact shields along the beam pipe. This paper describes compact effective concatenated magnetic shields for IFMIF-EVEDA LIPAc LEBT and MEBT and for FAIR Proton Linac injector. They protect the ACCT Current Transformers beyond 37 mT radial external fields. Measurements made at Saclay on the SILHI source are presented.

  20. Eddy-Current Measurement Of Turning Or Curvature

    NASA Technical Reports Server (NTRS)

    Chern, Engmin J.

    1993-01-01

    Rotatable conductive plate covers sensing coil to varying degree. Curvature of pipe at remote or otherwise inaccessible location inside pipe measured using relatively simple angular-displacement eddy-current probe. Crawler and sensor assemblies move along inside of pipe on wheels. Conductive plate pivots to follow curvature of pipe, partly covering one of eddy-current coils to degree depending on local curvature on pipe.

  1. Validation of streamflow measurements made with acoustic doppler current profilers

    USGS Publications Warehouse

    Oberg, K.; Mueller, D.S.

    2007-01-01

    The U.S. Geological Survey and other international agencies have collaborated to conduct laboratory and field validations of acoustic Doppler current profiler (ADCP) measurements of streamflow. Laboratory validations made in a large towing basin show that the mean differences between tow cart velocity and ADCP bottom-track and water-track velocities were -0.51 and -1.10%, respectively. Field validations of commercially available ADCPs were conducted by comparing streamflow measurements made with ADCPs to reference streamflow measurements obtained from concurrent mechanical current-meter measurements, stable rating curves, salt-dilution measurements, or acoustic velocity meters. Data from 1,032 transects, comprising 100 discharge measurements, were analyzed from 22 sites in the United States, Canada, Sweden, and The Netherlands. Results of these analyses show that broadband ADCP streamflow measurements are unbiased when compared to the reference discharges regardless of the water mode used for making the measurement. Measurement duration is more important than the number of transects for reducing the uncertainty of the ADCP streamflow measurement. ?? 2007 ASCE.

  2. In-situ measurements of velocity structure within turbidity currents

    USGS Publications Warehouse

    Xu, J. P.; Noble, M.A.; Rosenfeld, L.K.

    2004-01-01

    Turbidity currents are thought to be the main mechanism to move ???500,000 m3 of sediments annually from the head of the Monterey Submarine Canyon to the deep-sea fan. Indirect evidence has shown frequent occurrences of such turbidity currents in the canyon, but the dynamic properties of the turbidity currents such as maximum speed, duration, and dimensions are still unknown. Here we present the first-ever in-situ measurements of velocity profiles of four turbidity currents whose maximum along-canyon velocity reached 190 cm/s. Two turbidity currents coincided with storms that produced the highest swells and the biggest stream flows during the year-long deployment. Copyright 2004 by the American Geophysical Union.

  3. Simulation of vibration-induced effect on plasma current measurement using a fiber optic current sensor.

    PubMed

    Descamps, Frédéric; Aerssens, Matthieu; Gusarov, Andrei; Mégret, Patrice; Massaut, Vincent; Wuilpart, Marc

    2014-06-16

    An accurate measurement of the plasma current is of paramount importance for controlling the plasma magnetic equilibrium in tokamaks. Fiber optic current sensor (FOCS) technology is expected to be implemented to perform this task in ITER. However, during ITER operation, the vessel and the sensing fiber will be subject to vibrations and thus to time-dependent parasitic birefringence, which may significantly compromise the FOCS performance. In this paper we investigate the effects of vibrations on the plasma current measurement accuracy under ITER-relevant conditions. The simulation results show that in the case of a FOCS reflection scheme including a spun fiber and a Faraday mirror, the error induced by the vibrations is acceptable regarding the ITER current diagnostics requirements.

  4. Current Density Measurements of an Annular-Geometry Ion Engine

    NASA Technical Reports Server (NTRS)

    Shastry, Rohit; Patterson, Michael J.; Herman, Daniel A.; Foster, John E.

    2012-01-01

    The concept of the annular-geometry ion engine, or AGI-Engine, has been shown to have many potential benefits when scaling electric propulsion technologies to higher power. However, the necessary asymmetric location of the discharge cathode away from thruster centerline could potentially lead to non-uniformities in the discharge not present in conventional geometry ion thrusters. In an effort to characterize the degree of this potential nonuniformity, a number of current density measurements were taken on a breadboard AGI-Engine. Fourteen button probes were used to measure the ion current density of the discharge along a perforated electrode that replaced the ion optics during conditions of simulated beam extraction. Three Faraday probes spaced apart in the vertical direction were also used in a separate test to interrogate the plume of the AGI-Engine during true beam extraction. It was determined that both the discharge and the plume of the AGI-Engine are highly uniform, with variations under most conditions limited to 10% of the average current density in the discharge and 5% of the average current density in the plume. Beam flatness parameter measured 30 mm from the ion optics ranged from 0.85 0.95, and overall uniformity was shown to generally increase with increasing discharge and beam currents. These measurements indicate that the plasma is highly uniform despite the asymmetric location of the discharge cathode.

  5. In silico cell electrophysiology for measuring transcellular calcium currents

    NASA Astrophysics Data System (ADS)

    ul Haque, A.; Rokkam, M.; De Carlo, A. R.; Wereley, S. T.; Wells, H. W.; McLamb, W. T.; Roux, S. J.; Irazoqui, P. P.; Porterfield, D. M.

    2006-10-01

    Trans-cellular calcium currents play a central role in the establishment of polarity in differentiating cells. Typically these currents are measured and studied experimentally using ion selective glass microelectrodes. We have recently developed an in silico cell electrophysiology lab-on-a-chip device with the specific science objectives of measuring these transcellular calcium currents in an advanced throughput format. The device consists of 16 pyramidal pores on a silicon substrate with four Ag/AgCl electrodes leading into each pore on the four poles. An SU-8 layer is used as the structural and insulating layer and a calcium ion selective membrane is used to impart ion selectivity to the Ag/AgCl electrodes. In this paper we demonstrate the utility of the cell electrophysiology biochip in measuring these transcellular calcium currents from single cells using the model biological system Ceratopteris richardii. We monitored these fern spores during germination and pharmacologically inhibited biophysical calcium transport. These results demonstrate the utility and versatility of the in silico cell electrophysiology biochip. While this version of the biochip was engineered to fulfill the specific science objectives of measuring trans-cellular calcium currents from Ceratopteris fern spores, the chip can easily be modified for a variety of biomedical and pharmacological applications. Future

  6. Current Density Measurements of an Annular-Geometry Ion Engine

    NASA Technical Reports Server (NTRS)

    Shastry, Rohit; Patterson, Michael J.; Herman, Daniel A.; Foster, John E.

    2012-01-01

    The concept of the annular-geometry ion engine, or AGI-Engine, has been shown to have many potential benefits when scaling electric propulsion technologies to higher power. However, the necessary asymmetric location of the discharge cathode away from thruster centerline could potentially lead to non-uniformities in the discharge not present in conventional geometry ion thrusters. In an effort to characterize the degree of this potential non-uniformity, a number of current density measurements were taken on a breadboard AGI-Engine. Fourteen button probes were used to measure the ion current density of the discharge along a perforated electrode that replaced the ion optics during conditions of simulated beam extraction. Three Faraday probes spaced apart in the vertical direction were also used in a separate test to interrogate the plume of the AGI-Engine during true beam extraction. It was determined that both the discharge and the plume of the AGI-Engine are highly uniform, with variations under most conditions limited to +/-10% of the average current density in the discharge and +/-5% of the average current density in the plume. Beam flatness parameter measured 30 mm from the ion optics ranged from 0.85 - 0.95, and overall uniformity was shown to generally increase with increasing discharge and beam currents. These measurements indicate that the plasma is highly uniform despite the asymmetric location of the discharge cathode.

  7. Low level CO2 effects on pulmonary function in humans

    NASA Technical Reports Server (NTRS)

    Sexton, J.; Mueller, K.; Elliott, A.; Gerzer, D.; Strohl, K. P.; West, J. B. (Principal Investigator)

    1998-01-01

    The purpose of the study was to determine whether chamber exposure to low levels of CO2 results in functional alterations in gas mixing and closing volume in humans. Four healthy volunteer subjects were exposed to 0.7% CO2 and to 1.2% CO2. Spirometry, lung volumes, single breath nitrogen washout, diffusing capacity for carbon monoxide (DLCO) by two methods, and cardiac output were measured in triplicate. Values were obtained over two non-consecutive days during the training period (control) and on days 2 or 3, 4, 6, 10, 13, and 23 of exposure to each CO2 level. Measurements were made during the same time of day. There was one day of testing after exposure, while still in the chamber but off carbon dioxide. The order of testing, up until measurements of DLCO and cardiac output, were randomized to avoid presentation effects. The consistent findings were a reduction in diffusing capacity for carbon monoxide and a fall in cardiac output, occurring to a similar degree with both exposures. For the group as a whole, there was no indication of major effects on spirometry, lung volumes, gas mixing or dead space. We conclude that small changes may occur in the function of distal gas exchanging units; however, these effects were not associated with any adverse health effects. The likelihood of pathophysiologic changes in lung function or structure with 0.7 or 1.2% CO2 exposure for this period of time, is therefore, low.

  8. Ultra-low level radon assays in gases

    SciTech Connect

    Liu, Xin Ran

    2015-08-17

    The SuperNEMO experiment aims to search for the neutrinoless double beta decay (0νβ β) to T{sub 1{sub /{sub 2}}}(0ν) > 10{sup 26} years, this corresponds to an effective neutrino mass of 50-100 meV. The extremely rare event rate means the minimisation of background is of critical concern. The stringent strategy instigated to ensure detector radiopurity is outlined here for all construction materials. In particular the large R&D programme undertaken to reach the challengingly low level of radon, < 0.15 mBq/m{sup 3}, required inside the SuperNEMO gaseous tracker will be detailed. This includes an experiment designed to measure radon diffusion through various materials. A “Radon Concentration Line” (RnCL) was developed to be used in conjunction with a state-of-the-art radon detector in order to achieve world leading sensitivity to {sup 222}Rn content in large gas volumes at the level of a few µBq/m{sup 3}. A radon purification system was developed and installed which has demonstrated radon suppression by several orders of magnitude depending on the carrier gas. This apparatus has now been commissioned and measurements of cylindered gas have been made to confirm radon suppression by a factor 20 when using nitrogen as the carrier gas. The results from measurements of radon content in various gases, used inside SuperNEMO, using the RnCL will be presented.

  9. Measurement of the Rydberg ionization current in thermal vapor cells

    NASA Astrophysics Data System (ADS)

    Loew, Robert; Barredo, Daniel; Daschner, Renate; Kuebler, Harald; Ritter, Ralf; Pfau, Tilman

    2013-05-01

    Rydberg atoms confined in atomic vapor cells are promising candidates for the realization of single photon sources and quantum optical devices. To date, most information about the behavior of the Rydberg ensembles in thermal vapors has been extracted by absorptive measurements, e.g. EIT. However, to access directly quantities, like the population of the excited states, new methods are needed. In this task, the detection of the Rydberg ionization current provides a complementary and direct insight in the atomic processes. We show measurements of the Rydberg-ion current in thermal vapor cells equipped with field plates inside the vacuum. arXiv:1209.655.

  10. Pulsed eddy current thickness measurements of transuranic waste containers

    SciTech Connect

    O`Brien, T.K.; Kunerth, D.C.

    1995-12-31

    Thickness measurements on fifty five gallon waste drums for drum integrity purposes have been traditionally performed at the INEL using ultrasonic testing methods. Ultrasonic methods provide high resolution repeatable thickness measurements in a timely manner, however, the major drawback of using ultrasonic techniques is coupling to the drum. Areas with severe exterior corrosion, debonded paper labels or any other obstacle in the acoustic path will have to be omitted from the ultrasonic scan. We have developed a pulsed eddy current scanning system that can take thickness measurements on fifty five gallon carbon steel drums with wall thicknesses up to 65 mils. This type of measurement is not susceptible to the problems mentioned above. Eddy current measurements in the past have excluded ferromagnetic materials such as carbon steel because of the difficulty in penetrating the material and in compensating for changes in permeability from material to material. New developments in data acquisition electronics as well as advances in personal computers have made a pulsed eddy current system practical and inexpensive. Certain aspects of the pulsed eddy current technique as well as the operation of such a system and features such as real time pass/fail thresholds for overpacking identification and full scan data archiving for future evaluation will be discussed.

  11. A fiber-optic current sensor for lightning measurement applications

    NASA Astrophysics Data System (ADS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

    2015-05-01

    An optical-fiber sensor based on Faraday Effect is developed for measuring total lightning electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, lightning towers, and can help validate lightning detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered lightning measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial lightning test facility. The system was recently installed on an aircraft and flown near icing weather conditions.

  12. A Fiber-Optic Current Sensor for Lightning Measurement Applications

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

    2015-01-01

    An optical-fiber sensor based on Faraday Effect is developed for measuring total lightning electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, lightning towers, and can help validate lightning detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered lightning measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial lightning test facility. The system was recently installed on an aircraft and flown near icing weather conditions.

  13. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1990-10-01

    This report presents a history of commercial low-level radioactive waste management in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the 1980s to ensure the safe disposal of low-level waste in the 1990s and beyond. These steps include the issuance of Title 10 Code of Federal Regulations Part 61, Licensing Requirements for the Land Disposal of Radioactive Waste, the Low-Level Radioactive Waste Policy Act of 1980, the Low-Level Radioactive Waste Policy Amendments Act of 1985, and steps taken by states and regional compacts to establish additional disposal sites. 42 refs., 13 figs., 1 tab.

  14. Mixed and Low-Level Treatment Facility Project

    SciTech Connect

    Not Available

    1992-04-01

    This appendix contains the mixed and low-level waste engineering design files (EDFS) documenting each low-level and mixed waste stream investigated during preengineering studies for Mixed and Low-Level Waste Treatment Facility Project. The EDFs provide background information on mixed and low-level waste generated at the Idaho National Engineering Laboratory. They identify, characterize, and provide treatment strategies for the waste streams. Mixed waste is waste containing both radioactive and hazardous components as defined by the Atomic Energy Act and the Resource Conservation and Recovery Act, respectively. Low-level waste is waste that contains radioactivity and is not classified as high-level waste, transuranic waste, spent nuclear fuel, or 11e(2) byproduct material as defined by DOE 5820.2A. Test specimens of fissionable material irradiated for research and development only, and not for the production of power or plutonium, may be classified as low-level waste, provided the concentration of transuranic is less than 100 nCi/g. This appendix is a tool that clarifies presentation format for the EDFS. The EDFs contain waste stream characterization data and potential treatment strategies that will facilitate system tradeoff studies and conceptual design development. A total of 43 mixed waste and 55 low-level waste EDFs are provided.

  15. Interlaboratory Comparisons of NbTi Critical Current Measurements

    SciTech Connect

    Godeke, A.; Turrioni, D.; Boutboul, T.; Cheggour, N.; Goodrich, L.F.; Ghosh, A.; Den Ouden, A.; Meinesz, M.

    2009-08-16

    We report on a multi-institute comparison of critical current data measured on a modern NbTi wire for the Large Hadron Collider (LHC), which has shown a standard deviation below 1% in critical current density spread in more than 1500 measurements. Interlaboratory comparisons on Nb{sub 3}Sn wires have shown ambiguities that could be attributable to strain related differences in critical current density, originating from differences in sample handling, reaction, and mounting techniques, or also to differences in the magnetic field and current calibrations between the institutes. A round robin test of a well characterized NbTi wire provides a baseline variance in critical current results that is presumed to be attributable only to differences in the characterization systems. Systematic differences on the order of 3.5% are found in the comparison. The most likely cause for the observed differences is a small diameter holder that brings the wire into a strain regime in which strain effects can no longer be ignored. A NbTi round robin test, when performed properly, will separate system differences from sample specific differences and provide laboratories with an opportunity to calibrate equipment against a standard measurement.

  16. Measurement of tidal current fields with SRTM along track interferometry

    NASA Astrophysics Data System (ADS)

    Runge, H.; Breit, H.; Eineder, M.; Flament, P.; Romeiser, R.

    2003-04-01

    Although the Shuttle Radar Topography Mission (SRTM, http://www.dfd.dlr.de/srtm/) SAR interferometer was designed to deliver Digital Elevation Models from across track interferometry it turned out that it contained also an Along Track Interferometer (ATI). The paper describes how the ATI can be used to determine the velocity of moving ground objects. These may be cars, trains and ships but the focus of the paper is on the measurement of fast tidal ocean surface currents. The big advantage of the SAR-ATI method over buoys is that the measurement covers a large area and "images" of surface currents can be obtained.The advatage over the well established altimeter measurements is the much higher geometrical resolution and that it works close to coasts and in river outflows. Finally, the advantages over coastal radars is that a spaceborne system can deliver data from round the world. In the paper the results from two test sites, near Brest in France and in the Dutch Waddenzee, will be presented. Comparisons of the SRTM current fields with available current models of these areas show both a very good agreement. The ATI-method will be used in future SAR missions like TerraSAR-X to provide high resolution current maps from many interesting parts of the world.

  17. The Dose That Works: Low Level Laser Treatment of Tendinopathy

    NASA Astrophysics Data System (ADS)

    Tumilty, Steve; Munn, Joanne; McDonough, Suzanne; Hurley, Deirdre A.; Basford, Jeffrey R.; David Baxter, G.

    2010-05-01

    Background: Low Level Laser Therapy (LLLT) is used in the treatment of tendon injuries. However, the clinical effectiveness of this modality remains controversial with limited agreement on the most efficacious dosage and parameter choices. Purpose: To assess the clinical effectiveness of LLLT in the treatment of tendinopathy and the validity of current dosage recommendations for treatment. Method: Medical databases were searched from inception to 1st August 2008. Controlled clinical trials evaluating LLLT as a primary intervention for any tendinopathy were included in the review. Methodological quality was classified using the PEDro scale. Appropriateness of treatment parameters were assessed using established guidelines. Results: Twenty five trials met the inclusion criteria. There was conflicting findings from multiple trials: 12 showed positive effects and 13 were inconclusive or showed no effect. Dosages used in the 12 positive studies support the existence of an effective dosage window that closely resembled current guidelines. Where pooling of data was possible, LLLT showed a positive effect size; in high quality studies of lateral epicondylitis, participants' grip strength was 9.59 Kg higher than the control group; for participants with Achilles tendinopathy, the effect was 13.6 mm less pain on a 100 mm visual analogue scale. Conclusion: This study found conflicting evidence as to the effectiveness of LLLT in the treatment of tendinopathy. However, an effective dosage window emerged showing benefit in the treatment of tendinopathy. Strong evidence exists from the 12 positive studies that positive outcomes are associated with the use of current dosage recommendations for the treatment of tendinopathy.

  18. The Dose That Works: Low Level Laser Treatment of Tendinopathy

    SciTech Connect

    Tumilty, Steve; Munn, Joanne; David Baxter, G.; McDonough, Suzanne; Hurley, Deirdre A.; Basford, Jeffrey R.

    2010-05-31

    Background: Low Level Laser Therapy (LLLT) is used in the treatment of tendon injuries. However, the clinical effectiveness of this modality remains controversial with limited agreement on the most efficacious dosage and parameter choices. Purpose: To assess the clinical effectiveness of LLLT in the treatment of tendinopathy and the validity of current dosage recommendations for treatment. Method: Medical databases were searched from inception to 1st August 2008. Controlled clinical trials evaluating LLLT as a primary intervention for any tendinopathy were included in the review. Methodological quality was classified using the PEDro scale. Appropriateness of treatment parameters were assessed using established guidelines. Results: Twenty five trials met the inclusion criteria. There was conflicting findings from multiple trials: 12 showed positive effects and 13 were inconclusive or showed no effect. Dosages used in the 12 positive studies support the existence of an effective dosage window that closely resembled current guidelines. Where pooling of data was possible, LLLT showed a positive effect size; in high quality studies of lateral epicondylitis, participants' grip strength was 9.59 Kg higher than the control group; for participants with Achilles tendinopathy, the effect was 13.6 mm less pain on a 100 mm visual analogue scale. Conclusion: This study found conflicting evidence as to the effectiveness of LLLT in the treatment of tendinopathy. However, an effective dosage window emerged showing benefit in the treatment of tendinopathy. Strong evidence exists from the 12 positive studies that positive outcomes are associated with the use of current dosage recommendations for the treatment of tendinopathy.

  19. Lightning Return-Stroke Current Waveforms Aloft, From Measured Field Change, Current, and Channel Geometry

    NASA Technical Reports Server (NTRS)

    Willett, J. C.; LeVine, D. M.

    2002-01-01

    Direct current measurements are available near the attachment point from both natural cloud-to-ground lightning and rocket-triggered lightning, but little is known about the rise time and peak amplitude of return-stroke currents aloft. We present, as functions of height, current amplitudes, rise times, and effective propagation velocities that have been estimated with a novel remote-sensing technique from data on 24 subsequent return strokes in six different lightning flashes that were triggering at the NASA Kennedy Space Center, FL, during 1987. The unique feature of this data set is the stereo pairs of still photographs, from which three-dimensional channel geometries were determined previously. This has permitted us to calculate the fine structure of the electric-field-change (E) waveforms produced by these strokes, using the current waveforms measured at the channel base together with physically reasonable assumptions about the current distributions aloft. The computed waveforms have been compared with observed E waveforms from the same strokes, and our assumptions have been adjusted to maximize agreement. In spite of the non-uniqueness of solutions derived by this technique, several conclusions seem inescapable: 1) The effective propagation speed of the current up the channel is usually significantly (but not unreasonably) faster than the two-dimensional velocity measured by a streak camera for 14 of these strokes. 2) Given the deduced propagation speed, the peak amplitude of the current waveform often must decrease dramatically with height to prevent the electric field from being over-predicted. 3) The rise time of the current wave front must always increase rapidly with height in order to keep the fine structure of the calculated field consistent with the observations.

  20. Surface Current Measurements In Terra Nova Bay By Hf Radar

    NASA Astrophysics Data System (ADS)

    Flocco, D.; Falco, P.; Wadhams, P.; Spezie, G.

    We present the preliminary results of a field experiment carried out within frame- work of the CLIMA project of the Italian National Programme for Antarctic Research (PNRA) and in cooperation with the Scott Polar Research Institute of Cambridge. Dur- ing the second period (02/12/1999-23/01/2000) of the XV Italian expedition a coastal radar was used to characterize the current field in the area of Terra Nova Bay (TNB). One of the aims of the CLIMA (Climatic Long-term Interactions for the Mass balance in Antarctica) project is to determine the role of the polynya in the sea ice mass bal- ance, water structure and local climate. The OSCR-II experiment was planned in order to provide surface current measurements in the area of TNB polynya, one of the most important coastal polynya of the Ross Sea. OSCR (Ocean Surface Current Radar) is a shore based, remote sensing system designed to measure sea surface currents in coastal waters. Two radar sites (a master and a slave) provide with radial current mea- surements; data combined from both sites yield the total current vector. Unfortunately the master and slave stations did not work together throughout the whole period of the experiment. A description of the experiment and a discussion of the results, will be proposed.

  1. Algorithm for Unfolding Current from Faraday Rotation Measurement

    SciTech Connect

    Stephen E. Mitchell

    2008-05-23

    Various methods are described to translate Faraday rotation measurements into a useful representation of the dynamic current under investigation[1]. For some experiments, simply counting the “fringes” up to the turnaround point in the recorded Faraday rotation signal is sufficient in determining the peak current within some allowable fringe uncertainty. For many other experiments, a higher demand for unfolding the entire dynamic current profile is required. In such cases, investigators often rely extensively on user interaction on the Faraday rotation data by visually observing the data and making logical decisions on what appears to be turnaround points and/or inflections in the signal. After determining extrema, inflection points, and locations, a piece-wise, ΔI/Δt, representation of the current may be revealed with the proviso of having a reliable Verdet constant of the Faraday fiber or medium and time location for each occurring fringe. In this paper, a unique software program is reported which automatically decodes the Faraday rotation signal into a time-dependent current representation. System parameters such as the Faraday fiber’s Verdet constant and number of loops in the sensor are the only user-interface inputs. The central aspect of the algorithm utilizes a short-time Fourier transform (STFT) which reveals much of the Faraday rotation’s hidden detail necessary for unfolding the dynamic current measurement.

  2. Apparatus for measurement of critical current in superconductive tapes

    DOEpatents

    Coulter, J. Yates; DePaula, Raymond

    2002-01-01

    A cryogenic linear positioner which is primarily used for characterizing coated conductor critical current homogeneity at 75K is disclosed. Additionally, this tool can be used to measure the positional dependence of the coated conductor resistance at room temperature, and the room temperature resistance of the underlying YBCB coating without the overlaying protective cover of silver.

  3. Fiber-Optic Current Sensor Validation with Triggered Lightning Measurements

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

    2013-01-01

    A fiber optic current sensor based on the Faraday Effect is developed that is highly suitable for aircraft installation and can measure total current enclosed in a fiber loop down to DC. Other attributes include being small, light-weight, non-conducting, safe from electromagnetic interference, and free of hysteresis and saturation. The Faraday Effect causes light polarization to rotate when exposed to a magnetic field in the direction of light propagation. Measuring the induced light polarization rotation in fiber loops yields the total current enclosed. Two sensor systems were constructed and installed at Camp Blanding, Florida, measuring rocket-triggered lightning. The systems were similar in design but with different laser wavelengths, sensitivities and ranges. Results are compared to a shunt resistor as reference. The 850nm wavelength system tested in summer 2011 showed good result comparison early. However, later results showed gradual amplitude increase with time, attributed to corroded connections affecting the 50-ohm output termination. The 1550nm system also yielded good results in the summer 2012. The successful measurements demonstrate the fiber optic sensor's accuracies in capturing real lightning currents, and represent an important step toward future aircraft installation.

  4. Dynamic Harris current sheet thickness from Cluster current density and plasma measurements

    NASA Technical Reports Server (NTRS)

    Thompson, S. M.; Kivelson, M. G.; Khurana, K. K.; McPherron, R. L.; Weygand, J. M.; Balogh, A.; Reme, H.; Kistler, L. M.

    2005-01-01

    We use the first accurate measurements of current densities in the plasma sheet to calculate the half-thickness and position of the current sheet as a function of time. Our technique assumes a Harris current sheet model, which is parameterized by lobe magnetic field B(o), current sheet half-thickness h, and current sheet position z(sub o). Cluster measurements of magnetic field, current density, and plasma pressure are used to infer the three parameters as a function of time. We find that most long timescale (6-12 hours) current sheet crossings observed by Cluster cannot be described by a static Harris current sheet with a single set of parameters B(sub o), h, and z(sub o). Noting the presence of high-frequency fluctuations that appear to be superimposed on lower frequency variations, we average over running 6-min intervals and use the smoothed data to infer the parameters h(t) and z(sub o)(t), constrained by the pressure balance lobe magnetic field B(sub o)(t). Whereas this approach has been used in previous studies, the spatial gnuhen& now provided by the Cluster magnetometers were unavailable or not well constrained in earlier studies. We place the calculated hdf&cknessa in a magnetospheric context by examining the change in thickness with substorm phase for three case study events and 21 events in a superposed epoch analysis. We find that the inferred half-thickness in many cases reflects the nominal changes experienced by the plasma sheet during substorms (i.e., thinning during growth phase, thickening following substorm onset). We conclude with an analysis of the relative contribution of (Delta)B(sub z)/(Delta)X to the cross-tail current density during substorms. We find that (Delta)B(sub z)/(Delta)X can contribute a significant portion of the cross-tail c m n t around substorm onset.

  5. Hanford low-level tank waste interim performance assessment

    SciTech Connect

    Mann, F.M.

    1996-09-16

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single- and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and its performance as early as possible in the project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  6. Hanford low-level tank waste interim performance assessment

    SciTech Connect

    Mann, F.M.

    1997-09-12

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and performance early in the disposal system project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  7. Measurement of total ion current from vacuum arc plasmasources

    SciTech Connect

    Oks, Efim M.; Savkin, Konstantin P.; Yushkov, Georgiu Yu.; Nikolaev, Alexey G.; Anders, A.; Brown, Ian G.

    2005-07-01

    The total ion current generated by a vacuum arc plasma source was measured. The discharge system investigated allowed ion collection from the arc plasma streaming through a hemispherical mesh anode with geometric transparency of 72 percent. A range of different cathode materials was investigated, and the arc current was varied over the range 50-500 A. We find that the normalized ion current (Iion/Iarc) depends on the cathode material, with values in the range from 5 percent to 19 percent and generally greater for elements of low cohesive energy. The application of a strong axial magnetic field in the cathode and arc region leads to increased normalized ion current, but only by virtue of enhanced ion charge states formed in a strong magnetic field.

  8. Soil characterization methods for unsaturated low-level waste sites

    SciTech Connect

    Wierenga, P.J.; Young, M.H. . Dept. of Soil and Water Science); Gee, G.W.; Kincaid, C.T. ); Hills, R.G. . Dept. of Mechanical Engineering); Nicholson, T.J.; Cady, R.E. )

    1993-01-01

    To support a license application for the disposal of low-level radioactive waste (LLW), applicants must characterize the unsaturated zone and demonstrate that waste will not migrate from the facility boundary. This document provides a strategy for developing this characterization plan. It describes principles of contaminant flow and transport, site characterization and monitoring strategies, and data management. It also discusses methods and practices that are currently used to monitor properties and conditions in the soil profile, how these properties influence water and waste migration, and why they are important to the license application. The methods part of the document is divided into sections on laboratory and field-based properties, then further subdivided into the description of methods for determining 18 physical, flow, and transport properties. Because of the availability of detailed procedures in many texts and journal articles, the reader is often directed for details to the available literature. References are made to experiments performed at the Las Cruces Trench site, New Mexico, that support LLW site characterization activities. A major contribution from the Las Cruces study is the experience gained in handling data sets for site characterization and the subsequent use of these data sets in modeling studies.

  9. Advances in low-level jet research and future prospects

    NASA Astrophysics Data System (ADS)

    Liu, Hongbo; He, Mingyang; Wang, Bin; Zhang, Qinghong

    2014-02-01

    The low-level jet (LLJ) is closely related to severe rainfall events, air pollution, wind energy utilization, aviation safety, sandstorms, forest fire, and other weather and climate phenomena. Therefore, it has attracted considerable attention since its discovery. Scientists have carried out many studies on LLJs and made significant achievements during the past five or six decades. This article summarizes and assesses the current knowledge on this subject, and focuses in particular on three aspects: 1) LLJ classification, definition, distribution, and structure; 2) LLJ formation and evolutionary mechanisms; and 3) relationships between LLJ and rainfall, as well as other interdisciplinary fields. After comparing the status of LLJ research at home (China) and abroad, we then discuss the shortcomings of LLJ research in China. We suggest that this includes: coarse definitions of the LLJ, lack of observations and inadequate quality control, few thorough explorations of LLJ characteristics and formation mechanisms, and limited studies in interdisciplinary fields. The future prospects for several LLJ research avenues are also speculated.

  10. Low-level radioactive wastes. AMA Council on Scientific Affairs.

    PubMed

    1990-02-01

    Under a federal law, each state by January 1, 1993, must provide for safe disposal of its low-level radioactive wastes. Most of the wastes are from using nuclear power to produce electricity, but 25% to 30% are from medical diagnosis, therapy, and research. Exposures to radioactivity from the wastes are much smaller than those from natural sources, and federal standards limit public exposure. Currently operating disposal facilities are in Beatty, Nev, Barnwell, SC, and Richland, Wash. National policy encourages the development of regional facilities. Planning a regional facility, selecting a site, and building, monitoring, and closing the facility will be a complex project lasting decades that involves legislation, public participation, local and state governments, financing, quality control, and surveillance. The facilities will utilize geological factors, structural designs, packaging, and other approaches to isolate the wastes. Those providing medical care can reduce wastes by storing them until they are less radioactive, substituting nonradioactive compounds, reducing volumes, and incinerating. Physicians have an important role in informing and advising the public and public officials about risks involved with the wastes and about effective methods of dealing with them.

  11. Low-level radioactive wastes. Council on Scientific Affairs.

    PubMed

    1989-08-01

    Under a federal law, each state by January 1, 1993, must provide for safe disposal of its low-level radioactive wastes. Most of the wastes are from using nuclear power to produce electricity, but 25% to 30% are from medical diagnosis, therapy, and research. Exposures to radioactivity from the wastes are much smaller than those from natural sources, and federal standards limit public exposure. Currently operating disposal facilities are in Beatty, Nev, Barnwell, SC, and Richland, Wash. National policy encourages the development of regional facilities. Planning a regional facility, selecting a site, and building, monitoring, and closing the facility will be a complex project lasting decades that involves legislation, public participation, local and state governments, financing, quality control, and surveillance. The facilities will utilize geological factors, structural designs, packaging, and other approaches to isolate the wastes. Those providing medical care can reduce wastes by storing them until they are less radioactive, substituting nonradioactive compounds, reducing volumes, and incinerating. Physicians have an important role in informing and advising the public and public officials about risks involved with the wastes and about effective methods of dealing with them.

  12. Noninvasive low-level laser therapy for thrombocytopenia.

    PubMed

    Zhang, Qi; Dong, Tingting; Li, Peiyu; Wu, Mei X

    2016-07-27

    Thrombocytopenia is a common hematologic disorder that is managed primarily by platelet transfusions. We report here that noninvasive whole-body illumination with a special near-infrared laser cures acute thrombocytopenia triggered by γ-irradiation within 2 weeks in mice, as opposed to a 5-week recovery time required in controls. The low-level laser (LLL) also greatly accelerated platelet regeneration in the presence of anti-CD41 antibody that binds and depletes platelets, and prevented a severe drop in platelet count caused by a common chemotherapeutic drug. Mechanistically, LLL stimulated mitochondrial biogenesis specifically in megakaryocytes owing to polyploidy of the cells. LLL also protected megakaryocytes from mitochondrial injury and apoptosis under stress. The multifaceted effects of LLL on mitochondria bolstered megakaryocyte maturation; facilitated elongation, branching, and formation of proplatelets; and doubled the number of platelets generated from individual megakaryocytes in mice. LLL-mediated platelet biogenesis depended on megakaryopoiesis and was inversely correlated with platelet counts, which kept platelet biogenesis in check and effectively averted thrombosis even after repeated uses, in sharp contrast to all current agents that stimulate the differentiation of megakaryocyte progenitors from hematopoietic stem cells independently of platelet counts. This safe, drug-free, donor-independent modality represents a paradigm shift in the prophylaxis and treatment of thrombocytopenia. PMID:27464749

  13. Certification Plan, low-level waste Hazardous Waste Handling Facility

    SciTech Connect

    Albert, R.

    1992-06-30

    The purpose of this plan is to describe the organization and methodology for the certification of low-level radioactive waste (LLW) handled in the Hazardous Waste Handling Facility (HWHF) at Lawrence Berkeley Laboratory (LBL). This plan also incorporates the applicable elements of waste reduction, which include both up-front minimization and end-product treatment to reduce the volume and toxicity of the waste; segregation of the waste as it applies to certification; an executive summary of the Waste Management Quality Assurance Implementing Management Plan (QAIMP) for the HWHF and a list of the current and planned implementing procedures used in waste certification. This plan provides guidance from the HWHF to waste generators, waste handlers, and the Waste Certification Specialist to enable them to conduct their activities and carry out their responsibilities in a manner that complies with the requirements of WHC-WAC. Waste generators have the primary responsibility for the proper characterization of LLW. The Waste Certification Specialist verifies and certifies that LBL LLW is characterized, handled, and shipped in accordance with the requirements of WHC-WAC. Certification is the governing process in which LBL personnel conduct their waste generating and waste handling activities in such a manner that the Waste Certification Specialist can verify that the requirements of WHC-WAC are met.

  14. Lightning Return-Stroke Current Waveforms Aloft, from Measured Field Change, Current, and Channel Geometry

    NASA Technical Reports Server (NTRS)

    Willett, J. C.; LeVine, D. M.; Idone, V. P.

    2006-01-01

    Three-dimensional reconstructions of six rocket-triggered lightning channels are derived from stereo photographs. These reconstructed channels are used to infer the behavior of the current in return strokes above the ground from current waveforms measured at the channel base and electric-field-change waveforms measured at a range of 5.2 kilometers for 24 return strokes in these channels. Streak photographs of 14 of the same strokes are analyzed to determine the rise times, propagation speeds, and amplitudes of relative light intensity for comparison with the electrical inferences. Results include the following: 1) The fine structure of the field-change waveforms that were radiated by these subsequent return strokes can be explained, in large part, by channel geometry. 2) The average 10 - 90% rise time of the stroke current increased by about a factor of seven in our sample, from an observed 0.31 plus or minus 0.17 microseconds at the surface to an inferred 2.2 plus or minus 0.5 microcseconds at 1 kilometer path length above the surface. 3) The three-dimensional propagation speed of the current front averaged 1.80 plus or minus 0.24 X 10(exp 8) meters per second over channel lengths typically greater than 1 kilometer. 4) Assuming that the measured current was entirely due to the return stroke forced an unreasonably large and abrupt reduction in inferred current amplitude over the first few tens of meters above the surface, especially in cases when the leader was bright relative to its stroke. Therefore, a significant fraction of the current at the surface was probably due to the leader, at least in such cases. 5) Peak return-stroke currents decreased by approximately 37 plus or minus 12% from 100 meters to 1 kilometer of path length above the surface. Because of uncertainty about how to partition the measured current between leader and return stroke, we are unable to infer the variation of current amplitude near the ground.

  15. Damage to metallic samples produced by measured lightning currents

    NASA Technical Reports Server (NTRS)

    Fisher, Richard J.; Schnetzer, George H.

    1991-01-01

    A total of 10 sample disks of 2024-T3 aluminum and 4130 ferrous steel were exposed to rocket-triggered lightning currents at the Kennedy Space Center test site. The experimental configuration was arranged so that the samples were not exposed to the preliminary streamer, wire-burn, or following currents that are associated with an upward-initiated rocket-triggered flash but which are atypical of naturally initiated lightning. Return-stroke currents and continuing currents actually attaching to the sample were measured, augmented by close-up video recordings of approximately 3 feet of the channel above the sample and by 16-mm movies with 5-ms resolution. From these data it was possible to correlate individual damage spots with streamer, return-stroke, and continuing currents that produced them. Substantial penetration of 80-mil aluminum was produced by a continuing current of submedian amplitude and duration, and full penetration of a 35-mil steel sample occurred under an eightieth percentile continuing current. The primary purpose of the data acquired in these experiments is for use in improving and quantifying the fidelity of laboratory simulations of lightning burnthrough.

  16. Damage to metallic samples produced by measured lightning currents

    SciTech Connect

    Fisher, R.J.; Schnetzer, G.H.

    1991-01-01

    A total of 10 samples disks of 2024-T3 aluminum and 4130 ferrous steel were exposed to rocket-triggered lightning currents at the Kennedy Space Center test site in Florida during the summer of 1990. The experimental configuration was arranged so that the samples were not exposed to the preliminary streamer, wire-burn, or following currents that are associated with an upward-initiated rocket-triggered flash but which are a typical of naturally initiated lightning. Return-stroke currents and continuing currents actually attaching to the sample were measured, augmented by close-up video recordings of approximately 3 feet of the channel above the sample and by 16-mm movies with 5-ms resolution. From these data it was possible to correlate individual damage spots with streamer, return-stroke, and continuing currents that produced them. Substantial penetration of 80-mil aluminum was produced by a continuing current of submedian amplitude and duration, and full penetration of a 35-mil steel sample occurred under an eightieth percentile continuing current. The primary purpose of the data acquired in these experiments is for use in improving and quantifying the fidelity of laboratory simulations of lighting burnthrough. 9 refs., 8 figs.

  17. Treatability study for the bench-scale solidification of nonincinerable LDR low-level mixed waste

    SciTech Connect

    Gering, K.L.

    1993-01-01

    The focus of this report is the solidification of nonincinerable, land disposal restricted (LDR) low-level mixed waste generated at the Idaho National Engineering Laboratory. Benchscale solidification was performed on samples of this mixed waste, which was done under a Resource Conservation and Recovery Act treatability study. Waste forms included liquids, sludges, and solids, and treatment techniques included the use of conventional Portland cement and sulphur polymer cement (SPC). A total of 113 monoliths were made under the experimental design matrix for this study; 8 of these were ``blank`` monoliths (contained no waste). Thus, 105 monoliths were used to solidify 21.6 kg of mixed waste; 92 were made with Portland cement systems, and 13 were made with SPC. Recipes for all monoliths are given, and suggested recipes (as based on the minimized leaching of toxic components) are summarized. In most cases, the results presented herein indicate that solidification was successful in immobilizing toxic metals, thereby transforming low-level mixed waste into low-level nonhazardous waste. The ultimate goal of this project is to use appropriate solidification techniques, as described in the literature, to transform low-level mixed waste to low-level nonhazardous waste by satisfying pertinent disposal requirements for this waste. Disposal requirements consider the toxicity characteristic leaching procedure tests, a free liquids test, and radiological analyses. This work is meaningful in that it will provide a basis for the disposal of waste that is currently categorized as LDR low-level mixed waste.

  18. Treatability study for the bench-scale solidification of nonincinerable LDR low-level mixed waste

    SciTech Connect

    Gering, K. L.

    1993-01-01

    The focus of this report is the solidification of nonincinerable, land disposal restricted (LDR) low-level mixed waste generated at the Idaho National Engineering Laboratory. Benchscale solidification was performed on samples of this mixed waste, which was done under a Resource Conservation and Recovery Act treatability study. Waste forms included liquids, sludges, and solids, and treatment techniques included the use of conventional Portland cement and sulphur polymer cement (SPC). A total of 113 monoliths were made under the experimental design matrix for this study; 8 of these were blank'' monoliths (contained no waste). Thus, 105 monoliths were used to solidify 21.6 kg of mixed waste; 92 were made with Portland cement systems, and 13 were made with SPC. Recipes for all monoliths are given, and suggested recipes (as based on the minimized leaching of toxic components) are summarized. In most cases, the results presented herein indicate that solidification was successful in immobilizing toxic metals, thereby transforming low-level mixed waste into low-level nonhazardous waste. The ultimate goal of this project is to use appropriate solidification techniques, as described in the literature, to transform low-level mixed waste to low-level nonhazardous waste by satisfying pertinent disposal requirements for this waste. Disposal requirements consider the toxicity characteristic leaching procedure tests, a free liquids test, and radiological analyses. This work is meaningful in that it will provide a basis for the disposal of waste that is currently categorized as LDR low-level mixed waste.

  19. Operational Strategies for Low-Level Radioactive Waste Disposal Site in Egypt - 13513

    SciTech Connect

    Mohamed, Yasser T.

    2013-07-01

    The ultimate aims of treatment and conditioning is to prepare waste for disposal by ensuring that the waste will meet the waste acceptance criteria of a disposal facility. Hence the purpose of low-level waste disposal is to isolate the waste from both people and the environment. The radioactive particles in low-level waste emit the same types of radiation that everyone receives from nature. Most low-level waste fades away to natural background levels of radioactivity in months or years. Virtually all of it diminishes to natural levels in less than 300 years. In Egypt, The Hot Laboratories and Waste Management Center has been established since 1983, as a waste management facility for LLW and ILW and the disposal site licensed for preoperational in 2005. The site accepts the low level waste generated on site and off site and unwanted radioactive sealed sources with half-life less than 30 years for disposal and all types of sources for interim storage prior to the final disposal. Operational requirements at the low-level (LLRW) disposal site are listed in the National Center for Nuclear Safety and Radiation Control NCNSRC guidelines. Additional procedures are listed in the Low-Level Radioactive Waste Disposal Facility Standards Manual. The following describes the current operations at the LLRW disposal site. (authors)

  20. Hysteresis in Transport Critical-Current Measurements of Oxide Superconductors

    PubMed Central

    Goodrich, L. F.; Stauffer, T. C.

    2001-01-01

    We have investigated magnetic hysteresis in transport critical-current (Ic) measurements of Ag-matrix (Bi,Pb)2Sr2Ca2Cu3O10–x (Bi-2223) and AgMg-matrix Bi2Sr2CaCu2O8+x (Bi-2212) tapes. The effect of magnetic hysteresis on the measured critical current of high temperature superconductors is a very important consideration for every measurement procedure that involves more than one sweep of magnetic field, changes in field angle, or changes in temperature at a given field. The existence of this hysteresis is well known; however, the implications for a measurement standard or interlaboratory comparisons are often ignored and the measurements are often made in the most expedient way. A key finding is that Ic at a given angle, determined by sweeping the angles in a given magnetic field, can be 17 % different from the Ic determined after the angle was fixed in zero field and the magnet then ramped to the given field. Which value is correct is addressed in the context that the proper sequence of measurement conditions reflects the application conditions. The hysteresis in angle-sweep and temperature-sweep data is related to the hysteresis observed when the field is swept up and down at constant angle and temperature. The necessity of heating a specimen to near its transition temperature to reset it to an initial state between measurements at different angles and temperatures is discussed. PMID:27500042

  1. Non-Contact EDDY Current Hole Eccentricity and Diameter Measurement

    NASA Technical Reports Server (NTRS)

    Chern, E. James

    1998-01-01

    Precision holes are among the most critical features of a mechanical component. Deviations from permissible tolerances can impede operation and result in unexpected failure. We have developed an automated non-contact eddy current hole diameter and eccentricity measuring system. The operating principle is based on the eddy current lift-off effect, which is the coil impedance as a function of the distance between the coil and the test object. An absolute eddy current probe rotates in the hole. The impedance of each angular position is acquired and input to the computer for integration and analysis. The eccentricity of the hole is the profile of the impedance as a function of angular position as compared to a straight line, an ideal hole. The diameter of the hole is the sum of the diameter of the probe and twice the distance-calibrated impedance. An eddy current image is generated by integrating angular scans for a plurality of depths between the top and bottom to display the eccentricity profile. This system can also detect and image defects in the hole. The method for non-contact eddy current hole diameter and eccentricity measurement has been granted a patent by the U.S. Patent and Trademark Office.

  2. Normalized velocity profiles of field-measured turbidity currents

    USGS Publications Warehouse

    Xu, Jingping

    2010-01-01

    Multiple turbidity currents were recorded in two submarine canyons with maximum speed as high as 280 cm/s. For each individual turbidity current measured at a fixed station, its depth-averaged velocity typically decreased over time while its thickness increased. Some turbidity currents gained in speed as they traveled downcanyon, suggesting a possible self-accelerating process. The measured velocity profiles, first in this high resolution, allowed normalizations with various schemes. Empirical functions, obtained from laboratory experiments whose spatial and time scales are two to three orders of magnitude smaller, were found to represent the field data fairly well. The best similarity collapse of the velocity profiles was achieved when the streamwise velocity and the elevation were normalized respectively by the depth-averaged velocity and the turbidity current thickness. This normalization scheme can be generalized to an empirical function Y = exp(–αXβ) for the jet region above the velocity maximum. Confirming theoretical arguments and laboratory results of other studies, the field turbidity currents are Froude-supercritical.

  3. Managing low-level radioactive wastes: a proposed approach

    SciTech Connect

    Not Available

    1980-08-01

    This document is a consensus report of the Low-Level Waste Strategy Task Force. It covers system-wide issues; generation, treatment, and packaging; transportation; and disposal. Recommendations are made. (DLC)

  4. Bibliographic Data on Low-Level Radioactive Waste Documents

    1995-11-10

    The purpose of the system is to allow users (researchers, policy makers, etc) to identify existing documents on a range of subjects related to low-level radioactive waste management. The software is menu driven.

  5. Mixed Low-Level Radioactive Waste (MLLW) Primer

    SciTech Connect

    W. E. Schwinkendorf

    1999-04-01

    This document presents a general overview of mixed low-level waste, including the regulatory definitions and drivers, the manner in which the various kinds of mixed waste are regulated, and a discussion of the waste treatment options.

  6. Carotid baroreceptor influence on forearm vascular resistance during low level lower body negative pressure

    NASA Technical Reports Server (NTRS)

    Thompson, Cynthia A.; Ludwig, David A.; Convertino, Victor A.

    1991-01-01

    The degree of forearm vasoconstriction induced by low levels of lower body negative pressure (LBNP) provides a measure of the responsiveness of the cardiopulmonary baroreflex. The validity of this measurement is based on the assumption that this vasoconstriction response is not influenced by unloading of carotid baroreceptors. To test the hypothesis that arterial baroreceptor unloading does not alter the degree of forearm vascular resistance during low levels of LBNP, 12 subjects were exposed to -15 and -20 mm Hg LBNP with and without additional artificial (+ 10 mm Hg neck pressure) unloading of the carotid baroreceptors. There was no measurable influence of carotid unloading on forearm vascular resistance at either level of LBNP. It is concluded that forearm vascular resistance measured during cardiopulmonary baroreceptor unloading is unaffected by carotid baroreceptor unloading within the magnitude encountered during low levels of LBNP.

  7. Charged current inclusive measurements in MINERνA

    SciTech Connect

    Hurtado, Kenyi

    2015-05-15

    MINERvA is a neutrino scattering experiment stationed in the high intensity NuMI beam line at Fermilab, designed to measure neutrino cross sections, final states and nuclear effects on a variety of targets in the few-GeV region to reduce systematic uncertainties in oscillation experiments and provide new understanding of the nucleus. Here we present the current MINERvA results for inclusive charged current neutrino and anti-neutrino scattering in the active region of the detector and different neutrino cross section ratios with different nuclear targets.

  8. Do the Low Levels of Reading Course Material Continue? An Examination in a Forensic Psychology Graduate Program

    ERIC Educational Resources Information Center

    Clump, Michael A.; Doll, Jason

    2007-01-01

    Clump, Bauer, and Bradley (2004) and Burchfield and Sappington (2000) previously found extremely low levels of reading in undergraduate psychology courses. The current study investigated whether these low levels of reading are also found with graduate students, or if this value is altered by only investigating individuals who show continued…

  9. Body contouring using 635-nm low level laser therapy.

    PubMed

    Nestor, Mark S; Newburger, Jessica; Zarraga, Matthew B

    2013-03-01

    Noninvasive body contouring has become one of the fastest-growing areas of esthetic medicine. Many patients appear to prefer nonsurgical less-invasive procedures owing to the benefits of fewer side effects and shorter recovery times. Increasingly, 635-nm low-level laser therapy (LLLT) has been used in the treatment of a variety of medical conditions and has been shown to improve wound healing, reduce edema, and relieve acute pain. Within the past decade, LLLT has also emerged as a new modality for noninvasive body contouring. Research has shown that LLLT is effective in reducing overall body circumference measurements of specifically treated regions, including the hips, waist, thighs, and upper arms, with recent studies demonstrating the long-term effectiveness of results. The treatment is painless, and there appears to be no adverse events associated with LLLT. The mechanism of action of LLLT in body contouring is believed to stem from photoactivation of cytochrome c oxidase within hypertrophic adipocytes, which, in turn, affects intracellular secondary cascades, resulting in the formation of transitory pores within the adipocytes' membrane. The secondary cascades involved may include, but are not limited to, activation of cytosolic lipase and nitric oxide. Newly formed pores release intracellular lipids, which are further metabolized. Future studies need to fully outline the cellular and systemic effects of LLLT as well as determine optimal treatment protocols.

  10. Feedback Configuration Tools for LHC Low Level RF

    SciTech Connect

    Van Winkle, D.; Fox, J.; Mastorides, T.; Rivetta, C.; Baudrenghien, P.; Butterworth, A.; Molendijk, J.; /CERN

    2009-12-16

    The LHC Low Level RF System (LLRF) is a complex multi-VME crate system which is used to regulate the superconductive cavity gap voltage as well as to lower the impedance as seen by the beam through low latency feedback. This system contains multiple loops with several parameters to be set before the loops can be closed. In this paper, we present a suite of MATLAB based tools developed to perform the preliminary alignment of the RF stations and the beginnings of a closed loop model based alignment routine. We briefly introduce the RF system and in particular the base band (time domain noise based) network analyzer system built into the LHC LLRF. The main focus of this paper is the methodology of the algorithms used by the routines within the context of the overall system. Measured results are presented that validate the technique. Because the RF systems are located in a cavern 120 m underground in a location which is relatively un-accessible without beam and completely un-accessible with beam present or magnets are energized, these remotely operated tools are a necessity for the CERN LLRF team to maintain and tune their LLRF systems in a similar fashion as to what was done very successfully in PEP-II at SLAC.

  11. Reproductive toxicity of low-level lead exposure in men

    SciTech Connect

    Telisman, Spomenka Colak, Bozo; Pizent, Alica; Jurasovic, Jasna; Cvitkovic, Petar

    2007-10-15

    Parameters of semen quality, seminal plasma indicators of secretory function of the prostate and seminal vesicles, sex hormones in serum, and biomarkers of lead, cadmium, copper, zinc, and selenium body burden were measured in 240 Croatian men 19-52 years of age. The subjects had no occupational exposure to metals and no known other reasons suspected of influencing male reproductive function or metal metabolism. After adjusting for age, smoking, alcohol, blood cadmium, and serum copper, zinc, and selenium by multiple regression, significant (P<0.05) associations of blood lead (BPb), {delta}-aminolevulinic acid dehydratase (ALAD), and/or erythrocyte protoporphyrin (EP) with reproductive parameters indicated a lead-related increase in immature sperm concentration, in percentages of pathologic sperm, wide sperm, round sperm, and short sperm, in serum levels of testosterone and estradiol, and a decrease in seminal plasma zinc and in serum prolactin. These reproductive effects were observed at low-level lead exposure (BPb median 49 {mu}g/L, range 11-149 {mu}g/L in the 240 subjects) common for general populations worldwide. The observed significant synergistic effect of BPb and blood cadmium on increasing serum testosterone, and additive effect of a decrease in serum selenium on increasing serum testosterone, may have implications on the initiation and development of prostate cancer because testosterone augments the progress of prostate cancer in its early stages.

  12. Observation of cloud formation caused by low-level jets

    NASA Astrophysics Data System (ADS)

    Su, J.; McCormick, M. P.; Lei, L.

    2015-12-01

    We present the results of analyses performed on high-resolution remotely-sensed and in situ atmospheric measurements of the boundary layer and lower atmosphere centered over the northeast coast of the Hampton Roads body of water in southeast Virginia. This region is adjacent to the confluence of the Chesapeake Bay and the Atlantic Ocean where often times, low-level jets (LLJs) are found in the boundary layer during summer months. An East Hampton Roads Aerosol Flux (EHRAF) campaign, was conducted from the campus of Hampton University (HU) to examine small-scale aerosol transport using aerosol, Raman, and Doppler lidars, as well as rawindsondes over a one-week period in May 2014 . LLJs were observed from evening of 20 May to the morning of 21 May, and were found to lead to cloud formation. In this paper, the cloud formation caused by LLJs is analyzed using data that includes high-resolution profiles of: aerosol backscatter, turbulence structure, temperature, wind speed and direction, and water vapor. It is found that enhanced nighttime turbulence triggered by LLJs causes the aerosol and water vapor content of boundary layer to be lifted up forming a well-mixed region. We show that this region contains the cloud condensation nuclei that are very important for the formation of clouds.

  13. Effect of interstitial low level laser therapy on tibial defect

    NASA Astrophysics Data System (ADS)

    Lee, Sangyeob; Ha, Myungjin; Hwang, Donghyun; Yu, Sungkon; Jang, Seulki; Park, Jihoon; Radfar, Edalat; Kim, Hansung; Jung, Byungjo

    2016-03-01

    Tibial defect is very common musculoskeletal disorder which makes patient painful and uncomfortable. Many studies about bone regeneration tried to figure out fast bone healing on early phase. It is already known that low level laser therapy (LLLT) is very convenient and good for beginning of bone disorder. However, light scattering and absorption obstruct musculoskeletal therapy which need optimal photon energy delivery. This study has used an interstitial laser probe (ILP) to overcome the limitations of light penetration depth and scattering. Animals (mouse, C57BL/6) were divided into three groups: laser treated test group 1 (660 nm; power 10 mW; total energy 5 J) and test group 2 (660 nm; power 20 mW; total energy 10 J); and untreated control group. All animals were taken surgical operation to make tibial defect on right crest of tibia. The test groups were treated every 48 hours with ILP. Bone volume and X-ray attenuation coefficient were measured on 0, 14th and 28th day with u-CT after treatment and were used to evaluate effect of LLLT. Results show that bone volume of test groups has been improved more than control group. X-ray attenuation coefficients of each groups have slightly different. The results suggest that LLLT combined with ILP may affect on early phase of bone regeneration and may be used in various musculoskeletal disease in deep tissue layer.

  14. Leakage current measurements of a pixelated polycrystalline CVD diamond detector

    NASA Astrophysics Data System (ADS)

    Zain, R. M.; Maneuski, D.; O'Shea, V.; Bates, R.; Blue, A.; Cunnigham, L.; Stehl, C.; Berderman, E.; Rahim, R. A.

    2013-01-01

    Diamond has several desirable features when used as a material for radiation detection. With the invention of synthetic growth techniques, it has become feasible to look at developing diamond radiation detectors with reasonable surface areas. Polycrystalline diamond has been grown using a chemical vapour deposition (CVD) technique by the University of Augsburg and detector structures fabricated at the James Watt Nanofabrication Centre (JWNC) in the University of Glasgow in order to produce pixelated detector arrays. The anode and cathode contacts are realised by depositing gold to produce ohmic contacts. Measurements of I-V characteristics were performed to study the material uniformity. The bias voltage is stepped from -1000V to 1000V to investigate the variation of leakage current from pixel to pixel. Bulk leakage current is measured to be less than 1nA.

  15. Measurement realities of current collection in dynamic space plasma environments

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, Edward P.

    1990-01-01

    Theories which describe currents collected by conducting and non-conducting bodies immersed in plasmas have many of their concepts based upon the fundamentals of sheath-potential distributions and charged-particle behavior in superimposed electric and magnetic fields. Those current-collecting bodies (or electrodes) may be Langmuir probes, electric field detectors, aperture plates on ion mass spectrometers and retarding potential analyzers, or spacecraft and their rigid and tethered appendages. Often the models are incomplete in representing the conditions under which the current-voltage characteristics of the electrode and its system are to be measured. In such cases, the experimenter must carefully take into account magnetic field effects and particle anisotropies, perturbations caused by the current collection process itself and contamination on electrode surfaces, the complexities of non-Maxwellian plasma distributions, and the temporal variability of the local plasma density, temperature, composition and fields. This set of variables is by no means all-inclusive, but it represents a collection of circumstances guaranteed to accompany experiments involving energetic particle beams, plasma discharges, chemical releases, wave injection and various events of controlled and uncontrolled spacecraft charging. Here, an attempt is made to synopsize these diagnostic challenges and frame them within a perspective that focuses on the physics under investigation and the requirements on the parameters to be measured. Examples include laboratory and spaceborne applications, with specific interest in dynamic and unstable plasma environments.

  16. Associations of low-level urine cadmium with kidney function in lead workers

    PubMed Central

    Weaver, Virginia M.; Kim, Nam-Soo; Jaar, Bernard G.; Schwartz, Brian S.; Parsons, Patrick J.; Steuerwald, Amy J.; Todd, Andrew C.; Simon, David; Lee, Byung-Kook

    2010-01-01

    Objectives Low-level cadmium exposure, e.g., urinary cadmium < 2.0 μg/g creatinine, is widespread; recent data suggest nephrotoxicity even at these lower levels. Few studies have examined the impact of low-level cadmium exposure in workers who are occupationally exposed to other nephrotoxicants such as lead. Methods We evaluated associations of urine cadmium, a measure of cumulative dose, with four glomerular filtration measures and N-acetyl-β-D-glucosaminidase (NAG) in lead workers. Recent and cumulative lead dose was assessed via blood and tibia lead, respectively. Results In 712 lead workers, mean (SD) blood and tibia lead, urine cadmium, and estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease equation were 23.1 (14.1) μg/dl, 26.6 (28.9) μg Pb/g bone mineral, 1.15 (0.66) μg/g creatinine, and 97.4 (19.2) ml/min/1.73m2, respectively. After adjustment for age, sex, body mass index, urine creatinine, smoking, alcohol, education, annual income, diastolic blood pressure, current or former lead worker job status, new or returning study participant, and blood and tibia lead, higher ln-urine cadmium was associated with higher calculated creatinine clearance, eGFR (β = 8.7 ml/min/1.73 m2; 95% CI = 5.4, 12.1) and ln-NAG but lower serum creatinine. Conclusions Potential explanations for these results include a normal physiologic response in which urine cadmium levels reflect renal filtration; the impact of adjustment for urine dilution with creatinine in models of kidney outcomes; and cadmium-related hyperfiltration. PMID:20974743

  17. Servo-amplifiers for ion current measurement in mass spectrometry

    USGS Publications Warehouse

    Stacey, J.S.; Russell, R.D.; Kollar, F.

    1965-01-01

    A servo-voltmeter can provide a useful alternative to the d.c. amplifier or vibrating reed electrometer for the accurate measurement of mass spectrometer ion currents, and has some advantages which recommend its use in certain applications. A generalized analysis based on servomechanism theory is presented as an aid for understanding the design criteria for this type of device. Two existing systems are described and their operation and performance are examined.

  18. Measurement of axial injection displacement with trim coil current unbalance

    NASA Astrophysics Data System (ADS)

    Covo, Michel Kireeff

    2014-08-01

    The Dee probe used for measuring internal radial beam intensity shows large losses inside the radius of 20 cm of the 88 in. cyclotron. The current of the top and bottom innermost trim coil 1 is unbalanced to study effects of the axial injection displacement. A beam profile monitor images the ion beam bunches, turn by turn. The experimental bunch center of mass position is compared with calculations of the magnetic mirror effect displacement and shows good agreement.

  19. Measurement of axial injection displacement with trim coil current unbalance

    SciTech Connect

    Covo, Michel Kireeff

    2014-08-15

    The Dee probe used for measuring internal radial beam intensity shows large losses inside the radius of 20 cm of the 88 in. cyclotron. The current of the top and bottom innermost trim coil 1 is unbalanced to study effects of the axial injection displacement. A beam profile monitor images the ion beam bunches, turn by turn. The experimental bunch center of mass position is compared with calculations of the magnetic mirror effect displacement and shows good agreement.

  20. Comparison of BASS and VACM current measurements during STRESS

    USGS Publications Warehouse

    Lentz, Steven J.; Butman, Bradford; Williams, A. J.

    1995-01-01

    The equations used to convert VACM rotor rotation rates to current speed we based on a calibration study by Woodward and Appell rather than one based on a study by Cherriman that is routinely used at the Woods Hole Oceanographic Institution. The former yields closer agreement between the BASS and VACM speed measurements during STRESS (mean speed difference 0.2 cm s−1 versus 1.4 cm s−1).

  1. Low-Level Radioactive Waste temporary storage issues

    SciTech Connect

    Not Available

    1992-04-01

    The Low-Level Radioactive Waste Policy Act of 1980 gave responsibility for the disposal of commercially generated low-level radioactive waste to the States. The Low-Level Radioactive Waste Policy Amendments Act of 1985 attached additional requirements for specific State milestones. Compact regions were formed and host States selected to establish disposal facilities for the waste generated within their borders. As a result of the Low-Level Radioactive Waste Policy Amendments Act of 1985, the existing low-level radioactive waste disposal sites will close at the end of 1992; the only exception is the Richland, Washington, site, which will remain open to the Northwest Compact region only. All host States are required to provide for disposal of low-level radioactive waste by January 1, 1996. States also have the option of taking title to the waste after January 1, 1993, or taking title by default on January 1, 1996. Low-level radioactive waste disposal will not be available to most States on January 1, 1993. The most viable option between that date and the time disposal is available is storage. Several options for storage can be considered. In some cases, a finite storage time will be permitted by the Nuclear Regulatory Commission at the generator site, not to exceed five years. If disposal is not available within that time frame, other options must be considered. There are several options that include some form of extension for storage at the generator site, moving the waste to an existing storage site, or establishing a new storage facility. Each of these options will include differing issues specific to the type of storage sought.

  2. Low-Level Waste Drum Assay Intercomparison Study

    SciTech Connect

    Greutzmacher, K.; Kuzminski, J.; Myers, S. C.

    2003-02-26

    Nuclear waste assay is an integral element of programs such as safeguards, waste management, and waste disposal. The majority of nuclear waste is packaged in drums and analyzed by various nondestructive assay (NDA) techniques to identify and quantify the radioactive content. Due to various regulations and the public interest in nuclear issues, the analytical results are required to be of high quality and supported by a rigorous Quality Assurance (QA) program. A valuable QA tool is an intercomparison program in which a known sample is analyzed by a number of different facilities. While transuranic waste (TRU) certified NDA teams are evaluated through the Performance Demonstration Program (PDP), low-level waste (LLW) assay specialists have not been afforded a similar opportunity. NDA specialists from throughout the DOE complex were invited to participate in this voluntary drum assay intercomparison study that was organized and facilitated by the Solid Waste Operations and the Safeguards Science and Technology groups at the Los Alamos National Laboratory and by Eberline Services. Each participating NDA team performed six replicate blind measurements of two 55-gallon drums with relatively low-density matrices (a 19.1 kg shredded paper matrix and a 54.4 kg mixed metal, rubber, paper and plastic matrix). This paper presents the results from this study, with an emphasis on discussing the lessons learned as well as desirable follow up programs for the future. The results will discuss the accuracy and precision of the replicate measurements for each NDA team as well as any issues that arose during the effort.

  3. Direct-current proton-beam measurements at Los Alamos

    SciTech Connect

    Sherman, Joseph; Stevens, Ralph R.; Schneider, J. David; Zaugg, Thomas

    1995-09-15

    Recently, a CW proton accelerator complex was moved from Chalk River Laboratories (CRL) to Los Alamos National Laboratory. This includes a 50-keV dc proton injector with a single-solenoid low-energy beam transport system (LEBT) and a CW 1.25-MeV, 267-MHz radiofrequency quadrupole (RFQ). The move was completed after CRL had achieved 55-mA CW operation at 1.25 MeV using 250-kW klystrode tubes to power the RFQ. These accelerator components are prototypes for the front end of a CW linac required for an accelerator-driven transmutation linac, and they provide early confirmation of some CW accelerator components. The injector (ion source and LEBT) and emittance measuring unit are installed and operational at Los Alamos. The dc microwave ion source has been operated routinely at 50-keV, 75-mA hydrogen-ion current. This ion source has demonstrated very good discharge and H2 gas efficiencies, and sufficient reliability to complete CW RFQ measurements at CRL. Proton fraction of 75% has been measured with 550-W discharge power. This high proton fraction removes the need for an analyzing magnet. Proton LEBT emittance measurements completed at Los Alamos suggest that improved transmission through the RFQ may be achieved by increasing the solenoid focusing current. Status of the final CW RFQ operation at CRL and the installation of the RFQ at Los Alamos will be given.

  4. Direct-current proton-beam measurements at Los Alamos

    SciTech Connect

    Sherman, J.; Stevens, R.R.; Schneider, J.D.; Zaugg, T.

    1994-08-01

    Recently, a CW proton accelerator complex was moved from Chalk River Laboratories (CRL) to Los Alamos National Laboratory. This includes a 50-keV dc proton injector with a single-solenoid low-energy beam transport system (LEBT) and a CW 1.25-MeV, 267-MHz radiofrequency quadrupole (RFQ). The move was completed after CRL had achieved 55-mA CW operation at 1.25 MeV using 250-kW klystrode tubes to power the RFQ. These accelerator components are prototypes for the front end of a CW linac required for an accelerator-driven transmutation linac, and they provide early confirmation of some CW accelerator components. The injector (ion source and LEBT) and emittance measuring unit are installed and operational at Los Alamos. The dc microwave ion source has been operated routinely at 50-keV, 75-mA hydrogen-ion current. This ion source has demonstrated very good discharge and H{sub 2} gas efficiencies, and sufficient reliability to complete CW RFQ measurements at CRL. Proton fraction of 75% has been measured with 550-W discharge power. This high proton fraction removes the need for an analyzing magnet. Proton LEBT emittance measurements completed at Los Alamos suggest that improved transmission through the RFQ may be achieved by increasing the solenoid focusing current. Status of the final CW RFQ operation at CRL and the installation of the RFQ at Los Alamos is given.

  5. Melatonin protection from chronic, low-level ionizing radiation.

    PubMed

    Reiter, Russel J; Korkmaz, Ahmet; Ma, Shuran; Rosales-Corral, Sergio; Tan, Dun-Xian

    2011-12-15

    In the current survey, we summarize the published literature which supports the use of melatonin, an endogenously produced molecule, as a protective agent against chronic, low-level ionizing radiation. Under in vitro conditions, melatonin uniformly was found to protect cellular DNA and plasmid super coiled DNA from ionizing radiation damage due to Cs(137) or X-radiation exposure. Likewise, in an in vivo/in vitro study in which humans were given melatonin orally and then their blood lymphocytes were collected and exposed to Cs(137) ionizing radiation, nuclear DNA from the cells of those individuals who consumed melatonin (and had elevated blood levels) was less damaged than that from control individuals. In in vivo studies as well, melatonin given to animals prevented DNA and lipid damage (including limiting membrane rigidity) and reduced the percentage of animals that died when they had been exposed to Cs(137) or Co(60) radiation. Melatonin's ability to protect macromolecules from the damage inflicted by ionizing radiation likely stems from its high efficacy as a direct free radical scavenger and possibly also due to its ability to stimulate antioxidative enzymes. Melatonin is readily absorbed when taken orally or via any other route. Melatonin's ease of self administration and its virtual absence of toxicity or side effects, even when consumed over very long periods of time, are essential when large populations are exposed to lingering radioactive contamination such as occurs as a result of an inadvertent nuclear accident, an intentional nuclear explosion or the detonation of a radiological dispersion device, i.e., a "dirty" bomb. PMID:22185900

  6. Simulation of the Low-Level-Jet by general circulation models

    SciTech Connect

    Ghan, S.J.

    1996-04-01

    To what degree is the low-level jet climatology and it`s impact on clouds and precipitation being captured by current general circulation models? It is hypothesised that a need for a pramaterization exists. This paper describes this parameterization need.

  7. Policy analysis of the low-level radioactive waste-disposal problem in the United States

    SciTech Connect

    Maloney, S.; Sterman, J.D.

    1982-05-01

    Federal policy governing the control of low-level radioactive waste resulting from commercial nuclear reactor operations is currently undergoing development. A simulation model examines the effects of various options, including volume reduction, local waste-disposal limits, the use of the U. S. Department of Energy sites, and expedited licensing of disposal sites.

  8. Method and apparatus for deflection measurements using eddy current effects

    NASA Technical Reports Server (NTRS)

    Chern, Engmin J. (Inventor)

    1993-01-01

    A method and apparatus for inserting and moving a sensing assembly with a mechanical positioning assembly to a desired remote location of a surface of a specimen under test and measuring angle and/or deflection by sensing the change in the impedance of at least one sensor coil located in a base plate which has a rotatable conductive plate pivotally mounted thereon so as to uncover the sensor coil(s) whose impedance changes as a function of deflection away from the center line of the base plate in response to the movement of the rotator plate when contacting the surface of the specimen under test is presented. The apparatus includes the combination of a system controller, a sensing assembly, an eddy current impedance measuring apparatus, and a mechanical positioning assembly driven by the impedance measuring apparatus to position the sensing assembly at a desired location of the specimen.

  9. An alternative viewpoint to the biological effects of low-level exposures

    SciTech Connect

    Cook, R.R.

    1995-12-31

    The effects of low-level exposures to toxic chemicals and radiations are presumed to be similar to those associated with higher level exposures. There is a growing body of evidence that this assumption is incorrect. Through a series of data-based examples, this paper challenges the assumptions inherent to the current toxics model and offers three alternatives: nonlinear dose response in which the effects seen at low levels may be interpreted as paradoxical, or even beneficial; a holistic model in which the outcome is the whole animal; and a trade-off model in which the unit of study is the population and not an individual.

  10. Remote-Handled Low Level Waste Disposal Project Alternatives Analysis

    SciTech Connect

    David Duncan

    2010-10-01

    This report identifies, evaluates, and compares alternatives for meeting the U.S. Department of Energy’s mission need for management of remote-handled low-level waste generated by the Idaho National Laboratory and its tenants. Each alternative identified in the Mission Need Statement for the Remote-Handled Low-Level Waste Treatment Project is described and evaluated for capability to fulfill the mission need. Alternatives that could meet the mission need are further evaluated and compared using criteria of cost, risk, complexity, stakeholder values, and regulatory compliance. The alternative for disposal of remote-handled low-level waste that has the highest confidence of meeting the mission need and represents best value to the government is to build a new disposal facility at the Idaho National Laboratory Site.

  11. Commission operation. National Low-Level Radioactive Waste Management Program

    NASA Astrophysics Data System (ADS)

    1984-09-01

    Since Congress enacted the Low-Level Radioactive Waste Policy Act, the states have prepared to meet their responsibilities for management of low-level radioactive waste by entering into regional compacts. This option document is intended to provide a framework for the operation of a compact commission formed as the governing body of a low-level radioactive waste compact. The document is designed to be easily modified to meet the needs of various regional compacts. The ideas and format presented were taken in general from the Federal Administrative procedures Act, various state administrative procedures, and the state regulatory agencies' rules of procedure. Requirements of filing, time frames, and standard language are written from a legal perspective.

  12. Low-level radioactive waste: Gamma rays in the garbage

    SciTech Connect

    Saleska, S. )

    1990-04-01

    Of the four categories of radioactive waste (uranium mill tailings, high-level waste, transuranic, and low-level), the last term, low-level, proves to be the most misleading. The author suggests that a better term for this category would be miscellaneous radioactive junk, since it is by definition everything not included in the other three categories. Ted Taylor, a New York State resident and physicist and former nuclear weapons designer, points out that this category includes such intensely radioactive materials as reactor components that would deliver in a few minutes a lethal dose of gamma rays to anyone standing nearby. It is pointed out that of the original 6 low-level radioactive waste disposal sites, only 3 are still operating and two of those are slated to be closed in 1993 when they will be full. Unquestionably, new standards and policies are needed to deal sensibly with the problem; these are discussed briefly. 9 refs.

  13. Low Level Laser Therapy: A Panacea for oral maladies

    PubMed Central

    Kathuria, Vartika; Kalra, Gauri

    2015-01-01

    Aim: To review the applications of low level laser therapy on various soft and hard oral tissues. A variety of therapeutic effects of Low Level Laser Therapy have been reported on a broad range of disorders. It has been found amenably practical in dental applications including soft as well as hard tissues of the oral cavity. LLLT has been found to be efficient in acceleration of wound healing, enhanced remodelling and bone repair, regeneration of neural cells following injury, pain attenuation, endorphin release stimulation and modulation of immune system. The aforementioned biological processes induced by Low level lasers have been effectively applied in treating various pathological conditions in the oral cavity. With is article, we attempt to review the possible application of Low Laser Therapy in the field of dentistry. PMID:26557737

  14. Current status of the measurement of the anapole moment

    NASA Astrophysics Data System (ADS)

    Sheng, Dong; Perez Galvan, Adrian; Hood, Jonathan; Orozco, Luis

    2009-05-01

    We present the current status of the experimental effort towards the measurement of the anapole moment in different isotopes of francium. The anapole is a parity-violating, time-reversal conserving nuclear moment that arises from the weak interaction among nucleons. Due to the electromagnetic interaction between electrons and nucleons, atomic physics gives the unique possibility to probe the weak interaction in the low energy regime. Our experimental scheme involves driving a parity forbidden E1 transition between hyperfine ground states in a series of francium isotopes inside a blue detuned dipole trap at the electric antinode of a microwave cavity. The experiment will make use of the ISAC radioactive beam facility at TRIUMF. The system is currently being tested with rubidium.

  15. Nausea: current knowledge of mechanisms, measurement and clinical impact.

    PubMed

    Kenward, Hannah; Pelligand, Ludovic; Savary-Bataille, Karine; Elliott, Jonathan

    2015-01-01

    Nausea is a subjective sensation, which often acts as a signal that emesis is imminent. It is a widespread problem that occurs as a clinical sign of disease or as an adverse effect of a drug therapy or surgical procedure. The mechanisms of nausea are complex and the neural pathways are currently poorly understood. This review summarises the current knowledge of nausea mechanisms, the available animal models for nausea research and the anti-nausea properties of commercially available anti-emetic drugs. The review also presents subjective assessment and scoring of nausea. A better understanding of the underlying mechanisms of nausea might reveal potential clinically useful biomarkers for objective measurement of nausea in species of veterinary interest.

  16. Measurement of $$K^{+}$$ production in charged-current $$\

    DOE PAGES

    Marshall, C. M.

    2016-07-14

    Production of K+ mesons in charged-current νμ interactions on plastic scintillator (CH) is measured using MINERvA exposed to the low-energy NuMI beam at Fermilab. Timing information is used to isolate a sample of 885 charged-current events containing a stopping K+ which decays at rest. The differential cross section in K+ kinetic energy, dσ/dTK, is observed to be relatively flat between 0 and 500 MeV. As a result, its shape is in good agreement with the prediction by the genie neutrino event generator when final-state interactions are included, however the data rate is lower than the prediction by 15%.

  17. Common Graphics Library (CGL). Volume 2: Low-level user's guide

    NASA Technical Reports Server (NTRS)

    Taylor, Nancy L.; Hammond, Dana P.; Theophilos, Pauline M.

    1989-01-01

    The intent is to instruct the users of the Low-Level routines of the Common Graphics Library (CGL). The Low-Level routines form an application-independent graphics package enabling the user community to construct and design scientific charts conforming to the publication and/or viewgraph process. The Low-Level routines allow the user to design unique or unusual report-quality charts from a set of graphics utilities. The features of these routines can be used stand-alone or in conjunction with other packages to enhance or augment their capabilities. This library is written in ANSI FORTRAN 77, and currently uses a CORE-based underlying graphics package, and is therefore machine-independent, providing support for centralized and/or distributed computer systems.

  18. Observational and model evidence for positive low-level cloud feedback.

    PubMed

    Clement, Amy C; Burgman, Robert; Norris, Joel R

    2009-07-24

    Feedbacks involving low-level clouds remain a primary cause of uncertainty in global climate model projections. This issue was addressed by examining changes in low-level clouds over the Northeast Pacific in observations and climate models. Decadal fluctuations were identified in multiple, independent cloud data sets, and changes in cloud cover appeared to be linked to changes in both local temperature structure and large-scale circulation. This observational analysis further indicated that clouds act as a positive feedback in this region on decadal time scales. The observed relationships between cloud cover and regional meteorological conditions provide a more complete way of testing the realism of the cloud simulation in current-generation climate models. The only model that passed this test simulated a reduction in cloud cover over much of the Pacific when greenhouse gases were increased, providing modeling evidence for a positive low-level cloud feedback.

  19. The role of nitric oxide in low level light therapy

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.

    2008-02-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage by reducing cellular apoptosis has been known for almost forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. Firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of choosing amongst a large number of illumination parameters has led to the publication of a number of negative studies as well as many positive ones. This review will focus on the role of nitric oxide in the cellular and tissue effects of LLLT. Red and near-IR light is primarily absorbed by cytochrome c oxidase (unit four in the mitochondrial respiratory chain). Nitric oxide produced in the mitochondria can inhibit respiration by binding to cytochrome c oxidase and competitively displacing oxygen, especially in stressed or hypoxic cells. If light absorption displaced the nitric oxide and thus allowed the cytochrome c oxidase to recover and cellular respiration to resume, this would explain many of the observations made in LLLT. Why the effect is only seen in hypoxic, stressed or damaged cells or tissues? How the effects can keep working for some time (hours or days) postillumination? Why increased NO concentrations are sometimes measured in cell culture or in animals? How blood flow can be increased? Why angiogenesis is sometimes increased after LLLT in vivo?

  20. Model Evaluation for Low-Level Cloud Feedback

    NASA Astrophysics Data System (ADS)

    Shin, S.-H.

    2012-04-01

    , we give a courteous answer to the question of whether low-level clouds act as a positive or negative feedback to climate change.

  1. SECONDARY LOW-LEVEL WASTE GENERATION RATE ANALYSIS

    SciTech Connect

    D. LaRue

    1999-05-10

    The objective of this design analysis is -to update the assessment of estimated annual secondary low-level waste (LLW) generation rates resulting from the repackaging of spent nuclear fuel (SNF) and high-level waste (HLW) for disposal at the Monitored Geologic Repository (MGR). This analysis supports the preparation of documentation necessary for license application (LA) for the MGR. For the purposes of this analysis, secondary LLW is defined, in brief terms, as LLW generated as a direct result of processing SNF/HLW through the receiving and repackaging operations. The current Waste Handling Building (WHB) design is based on the predominant movement of fuel assemblies through the wet handling lines within the WHB. Dry handling lines are also included in the current WHB design to accommodate canistered waste (i.e., SNF and/or HLW packages). Major input changes to this analysis in comparison to previous analyses include: (1) changes in the SNF/HLW arrival schedules; (2) changes to the WHB and the Waste Treatment Building (WTB) dimensions; and (3) changes in operational staff sizes within the WHB and WTB. The rates generated in this analysis can be utilized to define necessary waste processes, waste flow rates, and equipment sizes for the processing of secondary LLW for proper disposal. This analysis is based on the present reference design, i.e., Viability Assessment (VA) design, and present projections on spent fuel delivery and processing. LLW generation rates, for both liquids and solids, are a direct function of square footages in radiological areas, and a direct function of spent fuel throughput. Future changes in the approved reference design or spent fuel throughput will directly impact the LLW generation rates defined in this analysis. Small amounts of wastes other than LLW may be generated on a non-routine basis. These wastes may include transuranic (TRU), hazardous, and mixed wastes. Although the objective of this analysis is to define LLW waste generation

  2. Dynamics of the Iberian Peninsula Coastal Low-Level Jet

    NASA Astrophysics Data System (ADS)

    Semedo, Alvaro; Rijo, Nádia; Miranda, Pedro; Lima, Daniela C. A.; Cardoso, Rita; Soares, Pedro

    2016-04-01

    Coastal low-level jets (CLLJ) are important mesoscale phenomena of some regional coastal climates. They are characterized by a coast-parallel flow which has a wind speed maxima within the first few hundred meters above sea level (usually below 1000 m, and most of the times around 500 m), encapsulated within the marine atmospheric boundary layer (MABL). Coastal jets have a larger scale synoptic forcing behind them: a high pressure system over the ocean and a thermal low inland. The regions where CLLJ occur coincide with cold equator-ward eastern boundary currents in the mid-latitudes (with an exception of the coast of Oman in the Arabian Sea), where the contrast between the cold ocean and the warm land in the summer is highest. As a response of CLLJ occurrences a positive feedback mechanism is triggered: the coast-parallel wind induces upwelling currents at the coast, reducing the sea surface temperature, which in turn increase the thermal (pressure) gradient at the coast, leading to higher wind speeds. The Iberian Peninsula Coastal Jet (IPCJ) is an example of a CLLJ, developed mostly during the summer season due to the effect of the semi-present Azores high-pressure system in the North Atlantic and of a thermal low pressure system inland. This synoptic pattern drives a seasonal (western) coast parallel wind, often called the Nortada (northerly wind), where the IPCJ develops. A detailed analysis of the IPCJ structure and dynamics will be presented, trough the analysis of two case studies off the west coast of Portugal. The case studies are simulated using the WRF mesoscale model, at 9 and 3 km horizontal resolution, forced by the ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-Interim reanalysis. The MABL structure off the west coast of Iberia, the interaction of the flow with the two main west Iberia capes (Finisterre and Roca), and the consequences on the cloud cover and wind speed up- and down-wind of the capes will be analysed.

  3. Closure Plan for Active Low Level Burial Grounds

    SciTech Connect

    SKELLY, W.A.

    2000-11-16

    This plan has been prepared in response to direction from the U.S. Department of Energy. The purpose of the plan is to define approaches that will be implemented to ensure protection of the public and the environment when active Low-Level Burial Grounds (LLBGs) at the Hanford Site are closed. Performance assessments for active burial grounds in the 200 East and West 200 Areas provide current estimates of potential environmental contamination and doses to the ''maximum exposed individual'' from burial ground operation and closure and compare dose estimates to performance objective dose limits for the facilities. This is an Operational Closure Plan. The intent of the guidance in DOE Order 435.1 is that this plan will be a living document, like the facility performance assessments, and will be revised periodically through the operational life of the LLBGs to reflect updated information on waste inventory. management practices, facility transition planning, schedule dates, assessments of post-closure performance, and environmental consequences. Out year dates identified in this plan are tentative. A Final Closure Plan will be prepared in the future when the timing and extent of closure-related activities for LLBGs can be established with greater certainty. After current operations at the LLBGs are concluded, this plan proposes transitioning of these facilities to the Environmental Restoration Program. This action will enable the Environmental Restoration Program to design and implement consistent and coordinated final remedial actions for active and inactive LLBGs. Active and inactive burial grounds in the 200 West and 200 East Areas are commingled. This plan describes approaches that will be implemented during Interim Closure, Final Closure, and Institutional Control Periods to prepare LLBGs for surface barriers, and the construction of barriers, as well as the scope of inspection, monitoring and maintenance practices that will be performed during and after closure

  4. GRABGAM Analysis of Ultra-Low-Level HPGe Gamma Spectra

    SciTech Connect

    Winn, W.G.

    1999-07-28

    The GRABGAM code has been used successfully for ultra-low level HPGe gamma spectrometry analysis since its development in 1985 at Savannah River Technology Center (SRTC). Although numerous gamma analysis codes existed at that time, reviews of institutional and commercial codes indicated that none addressed all features that were desired by SRTC. Furthermore, it was recognized that development of an in-house code would better facilitate future evolution of the code to address SRTC needs based on experience with low-level spectra. GRABGAM derives its name from Gamma Ray Analysis BASIC Generated At MCA/PC.

  5. A case study of a low level jet during OPALE

    NASA Astrophysics Data System (ADS)

    Gallée, H.; Barral, H.; Vignon, E.; Genthon, C.

    2014-12-01

    A case study of a low level jet during the OPALE (Oxidant Production over Antarctic Land and its Export) summer campaign is presented. It has been observed at Dome C (East Antarctica) and is simulated accurately by the three-dimensional version of the Modèle Atmosphérique Régional (MAR). It is found that this low level jet is not related to an episode of thermal wind, conforting that Dome C may be a~place where turbulence on flat terrain can be studied.

  6. A robotic inspector for low-level radioactive waste

    SciTech Connect

    Byrd, J.S.; Pettus, R.O.

    1996-06-01

    The Department of Energy has low-level radioactive waste stored in warehouses at several facilities. Weekly visual inspections are required. A mobile robot inspection system, ARIES (Autonomous Robotic Inspection Experimental System), has been developed to survey and inspect the stored drums. The robot will travel through the three- foot wide aisles of drums stacked four high and perform a visual inspection, normally performed by a human operator, making decisions about the condition of the drums and maintaining a database of pertinent information about each drum. This mobile robot system will improve the quality of inspection, generate required reports, and relieve human operators from low-level radioactive exposure.

  7. Modeling and low-level waste management: an interagency workshop

    SciTech Connect

    Little, C.A.; Stratton, L.E.

    1980-01-01

    The interagency workshop on Modeling and Low-Level Waste Management was held on December 1-4, 1980 in Denver, Colorado. Twenty papers were presented at this meeting which consisted of three sessions. First, each agency presented its point of view concerning modeling and the need for models in low-level radioactive waste applications. Second, a larger group of more technical papers was presented by persons actively involved in model development or applications. Last of all, four workshops were held to attempt to reach a consensus among participants regarding numerous waste modeling topics. Abstracts are provided for the papers presented at this workshop.

  8. Immobilized low-level waste disposal options configuration study

    SciTech Connect

    Mitchell, D.E.

    1995-02-01

    This report compiles information that supports the eventual conceptual and definitive design of a disposal facility for immobilized low-level waste. The report includes the results of a joint Westinghouse/Fluor Daniel Inc. evaluation of trade-offs for glass manufacturing and product (waste form) disposal. Though recommendations for the preferred manufacturing and disposal option for low-level waste are outside the scope of this document, relative ranking as applied to facility complexity, safety, remote operation concepts and ease of retrieval are addressed.

  9. A preliminary evaluation of alternatives for disposal of INEL low-level waste and low-level mixed waste

    SciTech Connect

    Smith, T.H.; Roesener, W.S.; Jorgenson-Waters, M.J.

    1993-07-01

    The Mixed and Low-Level Waste Disposal Facility (MLLWDF) project was established in 1992 by the US Department of Energy Idaho Operations Office to provide enhanced disposal capabilities for Idaho National Engineering Laboratory (INEL) low-level mixed waste and low-level waste. This Preliminary Evaluation of Alternatives for Disposal of INEL Low-Level Waste and Low-Level Mixed Waste identifies and evaluates-on a preliminary, overview basis-the alternatives for disposal of that waste. Five disposal alternatives, ranging from of no-action`` to constructing and operating the MLLWDF, are identified and evaluated. Several subalternatives are formulated within the MLLWDF alternative. The subalternatives involve various disposal technologies as well as various scenarios related to the waste volumes and waste forms to be received for disposal. The evaluations include qualitative comparisons of the projected isolation performance for each alternative, and facility, health and safety, environmental, institutional, schedule, and rough order-of-magnitude life-cycle cost comparisons. The performance of each alternative is evaluated against lists of ``musts`` and ``wants.`` Also included is a discussion of other key considerations for decisionmaking. The analysis of results indicated further study is necessary to obtain the best estimate of long-term future waste volume and characteristics from the INEL Environmental Restoration activities and the expanded INEL Decontamination and Decommissioning Program.

  10. Low Level and Transuranic Waste Segregation and Low Level Waste Characterization at the 200 Area of the Hanford Site - 12424

    SciTech Connect

    Donohoue, Tom; Martin, E. Ray; Mason, John A.; Blackford, Ty; Estes, Michael; Jasen, William; Cahill, Michael

    2012-07-01

    This paper describes the waste measurement and waste characterization activities carried out by ANTECH Corporation (ANTECH) and CH2M Hill Plateau Remediation Company (CHPRC) at the 200 Area of the Hanford Site under Contracts No. 22394 and No. 40245 for the US Department of Energy (DOE). These include Low Level Waste (LLW) and Transuranic (TRU) Waste segregation and LLW characterization for both 55-gallon (200-litre) drums with gross weight up to 454 kg and 85-gallon over-pack drums. In order to achieve efficient and effective waste drum segregation and assay, ANTECH deployed an automated Gamma Mobile Assay Laboratory (G-MAL) at the trench face in both 200 Area West and East. The unit consists of a modified 40 foot ISO shipping container with an automatic flow through roller conveyor system with internal drum weigh scale, four measurement and drum rotation positions, and four high efficiency high purity Germanium (HPGe) detectors with both detector and shadow shields. The unit performs multiple far-field measurements and is able to segregate drums at levels well below 100 nCi/g. The system is sufficiently sensitive that drums, which are classified as LLW, are characterized at measurement levels that meet the Environmental Restoration Disposal Facility (ERDF) Waste Acceptance Criteria (WAC). With measurement times of between 20 and 30 minutes the unit can classify and characterize over 40 drums in an 8-hour shift. The system is well characterized with documented calibrations, lower limits of detection (LLD) and total measurement uncertainty. The calibrations are confirmed and verified using nationally traceable standards in keeping with the CHPRC measurement requirements. The performance of the system has been confirmed and validated throughout the measurement process by independent CHPRC personnel using traceable standards. All of the measurement and maintenance work has been conducted during the period under a Quality Assurance Plan (QAP) compliant with the

  11. Dual-Band Deramp Radar Design for Ocean Current Measurements

    NASA Technical Reports Server (NTRS)

    Haynes, Mark S.

    2005-01-01

    A mission has been proposed to remotely measure ocean surface currents and surface wind velocities. It will provide the highest resolution and repeat time of these measurements to date for ocean current models with scientific and societal applications. A ground-based experimental radar unit is needed for proof of concept. The proposed experiment set up is to mount the radar on an oil rig to imitate satellite data acquisition. This summer, I completed the radar design. The design employs chirp/deramp topology with simultaneous transmit/receive channels. These two properties allow large system bandwidth, extended sample time, close range imaging, and low sampling rate. The radar operates in the Ku and Ka microwave bands, at 13.5 and 35.5 GHz, respectively, with a system bandwidth of 300 MHz. I completed the radar frequency analysis and research on potential components and antenna configurations. Subsequent work is needed to procure components, as well as to build, test, and deploy the radar.

  12. TESTING CPT SYMMETRY WITH CURRENT AND FUTURE CMB MEASUREMENTS

    SciTech Connect

    Li, Si-Yu; Zhang, Xinmin; Xia, Jun-Qing; Li, Hong; Li, Mingzhe

    2015-02-01

    In this paper, we use the current and future cosmic microwave background (CMB) experiments to test the Charge-Parity-Time Reversal (CPT) symmetry. We consider a CPT-violating interaction in the photon sector L{sub cs}∼p{sub μ}A{sub ν} F-tilde {sup μν}, which gives rise to a rotation of the polarization vectors of the propagating CMB photons. By combining the 9 yr WMAP, BOOMERanG 2003, and BICEP1 observations, we obtain the current constraint on the isotropic rotation angle α-bar =−2.12±1.14 (1σ), indicating that the significance of the CPT violation is about 2σ. Here, we particularly take the systematic errors of CMB measurements into account. Then, we study the effects of the anisotropies of the rotation angle [Δα( n-hat )] on the CMB polarization power spectra in detail. Due to the small effects, the current CMB polarization data cannot constrain the related parameters very well. We obtain the 95% C.L. upper limit of the variance of the anisotropies of the rotation angle C {sup α}(0) < 0.035 from all of the CMB data sets. More interestingly, including the anisotropies of rotation angle could lower the best-fit value of r and relax the tension on the constraints of r between BICEP2 and Planck. Finally, we investigate the capabilities of future Planck polarization measurements on α-bar and Δα( n-hat ). Benefited from the high precision of Planck data, the constraints of the rotation angle can be significantly improved.

  13. 60. VIEW OF LOW LEVEL CHECK STATION ON THE ARIZONA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. VIEW OF LOW LEVEL CHECK STATION ON THE ARIZONA CANAL, NEAR THE DEER VALLEY TREATMENT PLANT, LOOKING WEST. THE ARIZONA CANAL DIVERSION CHANNEL IS VISIBLE ON THE RIGHT SIDE OF THE PHOTOGRAPH Photographer: James Eastwood, July 1990 - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

  14. Mixed and Low-Level Waste Treatment Facility project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. The engineering studies, initiated in July 1991, identified 37 mixed waste streams, and 55 low-level waste streams. This report documents the waste stream information and potential treatment strategies, as well as the regulatory requirements for the Department of Energy-owned treatment facility option. The total report comprises three volumes and two appendices. This report consists of Volume 1, which explains the overall program mission, the guiding assumptions for the engineering studies, and summarizes the waste stream and regulatory information, and Volume 2, the Waste Stream Technical Summary which, encompasses the studies conducted to identify the INEL's waste streams and their potential treatment strategies.

  15. Effects of low levels of radiation on humans

    SciTech Connect

    Auxier, J.A.

    1981-01-01

    The state of knowledge on effects of low-level ionizing radiations on humans is reviewed. Several problems relating to dose thresholds or lack of thresholds for several types of cancer and high LET radiations and the effects of fractionation and dose protection are discussed. (ACR)

  16. Low-level waste vitrification contact maintenance viability study

    SciTech Connect

    Leach, C.E., Westinghouse Hanford

    1996-07-12

    This study investigates the economic viability of contact maintenance in the Low-Level Waste Vitrification Facility, which is part of the Hanford Site Tank Waste Remediation System. This document was prepared by Flour Daniel, Inc., and transmitted to Westinghouse Hanford Company in September 1995.

  17. Advanced Academic Skills in the Low-Level ESL Class.

    ERIC Educational Resources Information Center

    Pearson, Christine R.

    1981-01-01

    Suggests and gives examples of how a few advanced skills and concepts are related to successful reading and writing and can be introduced in low-level ESL classes. Examples include generality-specificity distinction, relevance-irrelevance distinction, underlining and making notes, paraphrasing, and summarizing. This conceptually integrated…

  18. Low-Level Violence: A Neglected Aspect of School Culture.

    ERIC Educational Resources Information Center

    Dupper, David R.; Meyer-Adams, Nancy

    2002-01-01

    Examines the extent of low-level violence in public schools and its impact on school performance, asserting that the way to reduce such violence is to create a more positive school culture and climate. Guidelines for preventing or minimizing such violence at school are presented. (SM)

  19. Credit WCT. Photographic copy of photograph, low level aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit WCT. Photographic copy of photograph, low level aerial view of Test Stand "D," looking due west, after completion of Dd station installation in 1961. Note Test Stand "D" "neutralization pond" to immediate southeast of tower. (JPL negative no. 384-2997-B, 12 December 1961) - Jet Propulsion Laboratory Edwards Facility, Test Stand D, Edwards Air Force Base, Boron, Kern County, CA

  20. Low-Level Waste Disposal Alternatives Analysis Report

    SciTech Connect

    Timothy Carlson; Kay Adler-Flitton; Roy Grant; Joan Connolly; Peggy Hinman; Charles Marcinkiewicz

    2006-09-01

    This report identifies and compares on-site and off-site disposal options for the disposal of contract-handled and remote-handled low-level waste generated by the Idaho National Laboratory and its tenants. Potential disposal options are screened for viability by waste type resulting in a short list of options for further consideration. The most crediable option are selected after systematic consideration of cost, schedule constraints, and risk. In order to holistically address the approach for low-level waste disposal, options are compiled into comprehensive disposal schemes, that is, alternative scenarios. Each alternative scenario addresses the disposal path for all low-level waste types over the period of interest. The alternative scenarios are compared and ranked using cost, risk and complexity to arrive at the recommended approach. Schedule alignment with disposal needs is addressed to ensure that all waste types are managed appropriately. The recommended alternative scenario for the disposal of low-level waste based on this analysis is to build a disposal facility at the Idaho National Laboratory Site.

  1. Environmentalism and low-level waste-the aftermath

    SciTech Connect

    Pastorelle, P.J.

    1995-05-01

    Radical Environmentalists, anxious to shut down nuclear power, are directing efforts against the disposal of low-level radioactive wastes (contaminated coveralls, tools, paper, plastic, glass, etc.). The rationals is that if nuclear power facilities cannot dispose of their waste streams, eventually they may have to stop operating. This article discusses the political and practical issues surrounding this approach.

  2. Peat: a natural repository for low-level radioactive waste

    SciTech Connect

    Thomas, E.D.

    1985-12-01

    A study has been initiated to evaluate the possibility of using peat as a natural repository for the disposal of low-level radioactive waste. One aspect of this study was to determine the retentive properties of the peat through measurements of the distribution coefficients (K/sub d/) for Am-241, Ru-106, Cs-137, Co-57, and Sr-85 in two layers of mountain top peat bogs from Lefgren's, NY, and Spruce Flats, PA. These K/sub d/ values were then compared to literature values of various sediment/water systems at similar environmental conditions. Am-241, Ru-106, Co-57, and Sr-85 attained distribution coefficients in the organic rich layers of the bogs two orders of magnitude greater than those obtained previously at pH 4.0. Although, the Cs-137 sorbed strongly to the inorganic rich layer of the Spruce Flats, PA, bog, the K/sub d/ values obtained for this isotope were, again, comparable or higher than those reported previously at pH 4.0, indicating the greater retentive properties of the peat. A chromatographic ''theoretical plate'' model was used to describe the field migration of Cs-137. The advection and diffusion coefficients were higher in the Lefgren's Bog, NY, than those obtained for the Spruce Flats Bog, PA. These field data were substantiated by the lower Cs-137 K/sub d/ values determined in the laboratory for the Lefgren's Bog, NY, compared to the Spruce Flats Bog. Although this model gave a good indication of the field migration, it neglected the process of sorption as defined by the sorption isotherm. Based on the time series data on distribution ratio measurements, a Cameron-Klute type of sorption isotherm was indicated, with rapid equilibrium initially superimposed onto a slower first order linear reversible equilibrium. This sorption isotherm can then be used in the final form of a model to describe the migration of radionuclides in a peat bog. 19 refs., 15 figs., 10 tabs.

  3. Influence of Emotion on the Control of Low-Level Force Production

    ERIC Educational Resources Information Center

    Naugle, Kelly M.; Coombes, Stephen A.; Cauraugh, James H.; Janelle, Christopher M.

    2012-01-01

    The accuracy and variability of a sustained low-level force contraction (2% of maximum voluntary contraction) was measured while participants viewed unpleasant, pleasant, and neutral images during a feedback occluded force control task. Exposure to pleasant and unpleasant images led to a relative increase in force production but did not alter the…

  4. Spin Seebeck measurements of current-induced switching in YIG

    NASA Astrophysics Data System (ADS)

    Bartell, Jason; Jermain, Colin; Aradhya, Sriharsha; Wang, Hailong; Buhrman, Robert; Yang, Fengyuan; Ralph, Daniel; Fuchs, Gregory

    Quantifying spin torques generated at the interface between a normal metal (NM) and a ferromagnetic insulator (FI) is an important step in understanding the spin hall effect without charge transport. Measuring magnetization in NM/FI devices is challenging, however, because both magnetoresistive and magneto-optical signals are tiny in thin-film bilayers. We show that a promising alternative measurement approach is the use of picosecond thermal gradients to study spin torques in Pt/Yttrium Iron Garnet (YIG) bilayers. Recently, we demonstrated the application of heat to stroboscopically transduce a local magnetic moment into an electrical signal via the time resolved anomalous Nernst effect (TRANE) in ferromagnetic metals. Using a similar geometry the spin Seebeck effect of YIG combined with the inverse spin Hall effect of Pt enables measurement of local magnetization. Here we describe our study using this technique to study current-induced switching in Pt/YIG with sub-10 nm thick YIG films We acknowledge support from AFOSR.

  5. High Accuracy Temperature Measurements Using RTDs with Current Loop Conditioning

    NASA Technical Reports Server (NTRS)

    Hill, Gerald M.

    1997-01-01

    To measure temperatures with a greater degree of accuracy than is possible with thermocouples, RTDs (Resistive Temperature Detectors) are typically used. Calibration standards use specialized high precision RTD probes with accuracies approaching 0.001 F. These are extremely delicate devices, and far too costly to be used in test facility instrumentation. Less costly sensors which are designed for aeronautical wind tunnel testing are available and can be readily adapted to probes, rakes, and test rigs. With proper signal conditioning of the sensor, temperature accuracies of 0.1 F is obtainable. For reasons that will be explored in this paper, the Anderson current loop is the preferred method used for signal conditioning. This scheme has been used in NASA Lewis Research Center's 9 x 15 Low Speed Wind Tunnel, and is detailed.

  6. Controlling low-level image properties: the SHINE toolbox.

    PubMed

    Willenbockel, Verena; Sadr, Javid; Fiset, Daniel; Horne, Greg O; Gosselin, Frédéric; Tanaka, James W

    2010-08-01

    Visual perception can be influenced by top-down processes related to the observer's goals and expectations, as well as by bottom-up processes related to low-level stimulus attributes, such as luminance, contrast, and spatial frequency. When using different physical stimuli across psychological conditions, one faces the problem of disentangling the contributions of low- and high-level factors. Here, we make available the SHINE (spectrum, histogram, and intensity normalization and equalization) toolbox for MATLAB, which we have found useful for controlling a number of image properties separately or simultaneously. The toolbox features functions for specifying the (rotational average of the) Fourier amplitude spectra, for normalizing and scaling mean luminance and contrast, and for exact histogram specification optimized for perceptual visual quality. SHINE can thus be employed for parametrically modifying a number of image properties or for equating them across stimuli to minimize potential low-level confounds in studies on higher level processes.

  7. Ocean dumping of low-level radioactive wastes

    NASA Astrophysics Data System (ADS)

    Templeton, W. L.

    1982-10-01

    Scientific bases, developed internationally over the last 20 years, to control and restrict to acceptable levels the resultant radiation doses that potentially could occur from the dumping of low-level radioactive wastes in the deep oceans were presented. It is concluded that present evaluations of the disposal of radioactive wastes into the oceans, coastal and deep ocean, indicate that these are being conducted within the ICRP recommended dose limits. However, there are presently no international institutions or mechanisms to deal with the long-term radiation exposure at low-levels to large numbers of people on a regional basis if not a global level. Recommendations were made to deal with these aspects through the established mechanisms of NEA/OECD and the London Dumping Convention, in cooperation with ICRP, UNSCEAR and the IAEA.

  8. Low level laser therapy in the treatment of aphthous ulcer.

    PubMed

    Anand, Vishal; Gulati, Minkle; Govila, Vivek; Anand, Bhargavi

    2013-01-01

    Recurrent aphthous stomatitis (RAS) is one of the most common and painful ulcerative lesions of the oral cavity, but until now no cure has been recognized for it. Two patients diagnosed with minor RAS were treated in a single sitting with low level laser therapy using 940-nm diode laser. The lesions healed completely within 3-4 days and a follow-up for 1 showed no recurrence in these patients. According to the results of this study, low level laser therapy can decrease the healing time, pain intensity, size, and recurrence of the lesion in patients with minor RAS, and hence can be considered the most appropriate treatment modality for minor RAS, with greatest clinical effectiveness.

  9. Low-level flow conditions hazardous to aircraft

    NASA Technical Reports Server (NTRS)

    Alexander, M. B.; Camp, D. W.

    1983-01-01

    Low level flow conditions known to be hazardous to aircraft during takeoff/climbout and approach/landing operations are turbulence, wind shear, and vertical motion. These conditions can and frequently do occur separately and in combinations. The identification and selection were completed of representative data cases to determine magnitude, frequency, duration, and simultaneity of occurrence of turbulence (gustiness and gust factor), wind shear (speed and direction), and vertical motion (updraft and downdraft), along with temperature inversions. New representations of temporal and spatial variations in the atmospheric boundary layer were developed. Efforts continued relative to low level flow conditions where published results imply strong vertical shear with virtually no horizontal shear and where order of magnitude analyses of the equations of motion for an aircraft illustrates that low values of horizontal shear (along the flight path) are much more hazardous than larger values of vertical wind shear (altitude).

  10. Low-level waste disposal in highly populated areas

    SciTech Connect

    Kowalski, E.; McCombie, C.; Issler, H.

    1989-11-01

    Nuclear-generated electricity supplies almost 40% of the demand in Switzerland (the rest being hydro-power). Allowing for a certain reserve and assuming an operational life-time of 40 years for each reactor, and taking into account wastes from decommissioning and from medicine, industry and research, the total amount of low-level radioactive waste to be disposed of is about 175,000 m{sup 3}. Since there are no unpopulated areas in Switzerland, and since Swiss Federal Law specifies that the safety of disposal may not depend upon supervision of the repository, no shallow-land burial has been foreseen, even for short-lived low-level waste. Instead, geological disposal in a mined cavern system with access through a horizontal tunnel was selected as the best way of meeting the requirements and ensuring the necessary public acceptance.

  11. Commercial low-level radioactive waste disposal in the US

    SciTech Connect

    Smith, P.

    1995-10-01

    Why are 11 states attempting to develop new low-level radioactive waste disposal facilities? Why is only on disposal facility accepting waste nationally? What is the future of waste disposal? These questions are representative of those being asked throughout the country. This paper attempts to answer these questions in terms of where we are, how we got there, and where we might be going.

  12. Chemical digestion of low level nuclear solid waste material

    DOEpatents

    Cooley, Carl R.; Lerch, Ronald E.

    1976-01-01

    A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230.degree.-300.degree.C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue.

  13. Department of Energy low-level radioactive waste disposal concepts

    SciTech Connect

    Ozaki, C.; Page, L.; Morreale, B.; Owens, C.

    1990-01-01

    The Department of Energy (DOE) manages its low-level waste (LLW), regulated by DOE Order 5820.2A by using an overall systems approach. This systems approach provides an improved and consistent management system for all DOE LLW waste, from generation to disposal. This paper outlines six basic disposal concepts used in the systems approach, discusses issues associated with each of the concepts, and outlines both present and future disposal concepts used at six DOE sites. 3 refs., 9 figs.

  14. Waste Management Facilities cost information for low-level waste

    SciTech Connect

    Shropshire, D.; Sherick, M.; Biadgi, C.

    1995-06-01

    This report contains preconceptual designs and planning level life-cycle cost estimates for managing low-level waste. The report`s information on treatment, storage, and disposal modules can be integrated to develop total life-cycle costs for various waste management options. A procedure to guide the US Department of Energy and its contractor personnel in the use of cost estimation data is also summarized in this report.

  15. The Argonne low level /sup 14/C counting system

    SciTech Connect

    Gray, J.; Rymas, S.J.; Studebaker, L.D.; Yule, H.P.

    1987-01-01

    A low level /sup 14/CO/sub 2/ counting system is described. This system was used to process several thousand CO/sub 2/ samples derived from atmospheric collections at various altitudes. Special features include counter construction utilizing electrolytic copper and shielding with neutron moderating and absorbing paraffin containing sodium metaborate. The effect of steel shielding thickness is shown, and the anticoincidence counters are described. Purification of the CO/sub 2/ for proportional counting is discussed. 5 refs., 3 figs.

  16. Mixed and Low-Level Waste Treatment Facility Project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. This report documents those studies so the project can continue with an evaluation of programmatic options, system tradeoff studies, and the conceptual design phase of the project. This report, appendix B, comprises the engineering design files for this project study. The engineering design files document each waste steam, its characteristics, and identified treatment strategies.

  17. Mixed and Low-Level Waste Treatment Facility project

    SciTech Connect

    Not Available

    1992-04-01

    Mixed and low-level wastes generated at the Idaho National Engineering Laboratory (INEL) are required to be managed according to applicable State and Federal regulations, and Department of Energy Orders that provide for the protection of human health and the environment. The Mixed and Low-Level Waste Treatment Facility Project was chartered in 1991, by the Department of Energy to provide treatment capability for these mixed and low-level waste streams. The first project task consisted of conducting engineering studies to identify the waste streams, their potential treatment strategies, and the requirements that would be imposed on the waste streams and the facilities used to process them. This report, Appendix A, Environmental Regulatory Planning Documentation, identifies the regulatory requirements that would be imposed on the operation or construction of a facility designed to process the INEL's waste streams. These requirements are contained in five reports that discuss the following topics: (1) an environmental compliance plan and schedule, (2) National Environmental Policy Act requirements, (3) preliminary siting requirements, (4) regulatory justification for the project, and (5) health and safety criteria.

  18. Management of low-level radioactive wastes around the world

    SciTech Connect

    Lakey, L.T.; Harmon, K.M.; Colombo, P.

    1985-04-01

    This paper reviews the status of various practices used throughout the world for managing low-level radioactive wastes. Most of the information in this review was obtained through the DOE-sponsored International Program Support Office (IPSO) activities at Pacific Northwest Laboratory (PNL) at Richland, Washington. The objective of IPSO is to collect, evaluate, and disseminate information on international waste management and nuclear fuel cycle activities. The center's sources of information vary widely and include the proceedings of international symposia, papers presented at technical society meetings, published topical reports, foreign trip reports, and the news media. Periodically, the information is published in topical reports. Much of the information contained in this report was presented at the Fifth Annual Participants' Information Meeting sponsored by DOE's Low-Level Waste Management Program Office at Denver, Colorado, in September of 1983. Subsequent to that presentation, the information has been updated, particularly with information provided by Dr. P. Colombo of Brookhaven National Laboratory who corresponded with low-level waste management specialists in many countries. The practices reviewed in this paper generally represent actual operations. However, major R and D activities, along with future plans, are also discussed. 98 refs., 6 tabls.

  19. A digital retina-like low-level vision processor.

    PubMed

    Mertoguno, S; Bourbakis, N G

    2003-01-01

    This correspondence presents the basic design and the simulation of a low level multilayer vision processor that emulates to some degree the functional behavior of a human retina. This retina-like multilayer processor is the lower part of an autonomous self-organized vision system, called Kydon, that could be used on visually impaired people with a damaged visual cerebral cortex. The Kydon vision system, however, is not presented in this paper. The retina-like processor consists of four major layers, where each of them is an array processor based on hexagonal, autonomous processing elements that perform a certain set of low level vision tasks, such as smoothing and light adaptation, edge detection, segmentation, line recognition and region-graph generation. At each layer, the array processor is a 2D array of k/spl times/m hexagonal identical autonomous cells that simultaneously execute certain low level vision tasks. Thus, the hardware design and the simulation at the transistor level of the processing elements (PEs) of the retina-like processor and its simulated functionality with illustrative examples are provided in this paper.

  20. Simulating Roll Clouds associated with Low-Level Convergence.

    NASA Astrophysics Data System (ADS)

    Prasad, A. A.; Sherwood, S. C.

    2015-12-01

    Convective initiation often takes place when features such as fronts and/or rolls collide, merge or otherwise meet. Rolls indicate boundary layer convergence and may initiate thunderstorms. These are often seen in satellite and radar imagery prior to the onset of deep convection. However, links between convergence driven rolls and convection are poor in global models. The poor representation of convection is the source of many model biases, especially over the Maritime Continent in the Tropics. We simulate low-level convergence lines over north-eastern Australia using the Weather Research and Forecasting (WRF) Model (version 3.7). The simulations are events from September-October 2002 driven by sea breeze circulations. Cloud lines associated with bore-waves that form along the low-level convergence lines are thoroughly investigated in this study with comparisons from satellite and surface observations. Initial simulations for a series of cloud lines observed on 4th October, 2002 over the Gulf of Carpentaria showed greater agreement in the timing and propagation of the disturbance and the low-level convergence, however the cloud lines or streets of roll clouds were not properly captured by the model. Results from a number of WRF simulations with different microphysics, cumulus and planetary boundary layer schemes, resolution and boundary conditions will also be discussed.

  1. The effects of radiative transfer on low-level cyclogenesis

    SciTech Connect

    Leach, M.J.; Raman, S.

    1995-04-01

    Many investigators have documented the role that thermodynamic forcing due to radiative flux divergence plays in the enhancement or generation of circulation. Most of these studies involve large-scale systems, small-scale systems such as thunderstorms, and squall lines. The generation of circulation on large scales results from the creation of divergence in the upper troposphere and the maintenance of low-level potentially unstable air, and the maintenance of baroclinicity throughout the atmosphere. On smaller scales, radiative flux divergence acts similarly. In the thunderstorms and squall lines, the radiative forcing acts as a pump, increasing the divergence at the top of the storm systems and increasing the updraft velocity and the intensity of inflow at mid-levels in the storm systems. Other researchers have examined the role of surface processes and low-level baroclinicity in east coast cyclogenesis. In this paper, we examine the interactive role that radiative flux divergence, clouds, and surface processes play in low-level cyclogenesis and the creation or maintenance of the boundary layer baroclinicity.

  2. Accelerator Mass Spectrometry Analysis of Ultra-Low-Level 129I in Carrier-Free AgI-AgCl Sputter Targets

    NASA Astrophysics Data System (ADS)

    Liu, Qi; Hou, Xiaolin; Zhou, Weijian; Fu, Yunchong

    2015-05-01

    Separation of carrier-free iodine from low-level iodine samples and accurate measurement of ultra-low-level 129I in microgram iodine target are essential but a bottleneck in geology and environment research using naturally produced 129I. This article presents a detection technique of accelerator mass spectrometry (AMS) for accurate determination of ultra-low-level 129I in carrier-free AgI-AgCl sputter targets. Copper instead of aluminum was selected as the suitable sample holder material to avoid the reaction of AgI-AgCl powder with aluminum. Niobium powder was selected as thermally and electrically conductive matrix to be mixed with AgI-AgCl powder, in order to obtain and maintain a stable and high iodine ion current intensity, as well as less memory effect and low background level of 129I. The most optimal ratio of the Nb matrix to the AgI-AgCl powder was found to be 5:1 by mass. The typical current of 127I5+ using AgI-AgCl targets with iodine content from 5 to 80 μg was measured to be 5 to 100 nA. Four-year AMS measurements of the 129I/127I ratios in standards of low iodine content and the machine blanks showed a good repeatability and stability.

  3. Accelerator mass spectrometry analysis of ultra-low-level (129)I in carrier-free AgI-AgCl sputter targets.

    PubMed

    Liu, Qi; Hou, Xiaolin; Zhou, Weijian; Fu, Yunchong

    2015-05-01

    Separation of carrier-free iodine from low-level iodine samples and accurate measurement of ultra-low-level (129)I in microgram iodine target are essential but a bottleneck in geology and environment research using naturally produced (129)I. This article presents a detection technique of accelerator mass spectrometry (AMS) for accurate determination of ultra-low-level (129)I in carrier-free AgI-AgCl sputter targets. Copper instead of aluminum was selected as the suitable sample holder material to avoid the reaction of AgI-AgCl powder with aluminum. Niobium powder was selected as thermally and electrically conductive matrix to be mixed with AgI-AgCl powder, in order to obtain and maintain a stable and high iodine ion current intensity, as well as less memory effect and low background level of (129)I. The most optimal ratio of the Nb matrix to the AgI-AgCl powder was found to be 5:1 by mass. The typical current of (127)I(5+) using AgI-AgCl targets with iodine content from 5 to 80 μg was measured to be 5 to 100 nA. Four-year AMS measurements of the (129)I/(127)I ratios in standards of low iodine content and the machine blanks showed a good repeatability and stability. PMID:25743113

  4. Effect of 635nm Low-level Laser Therapy on Upper Arm Circumference Reduction

    PubMed Central

    2012-01-01

    Objective: To assess the safety and efficacy of low-level laser therapy as a noninvasive method for reducing upper arm circumference. Design: Randomized, double-blind study whereby healthy subjects (N=40) with a body mass index of 20 to 35kg/m2 received three 20-minute low-level laser therapy (N=20) or sham treatments (N=20) each week for two weeks. Measurements: Upper arm circumference was measured after three and six treatments and two weeks post-treatment. Primary success criterion was the proportion of subjects achieving a combined reduction in arm circumference of ≥1.25cm measured at three equally spaced points between the elbow and the shoulder. Secondary outcomes included total measurement change at each time point and subjective satisfaction ratings. Results: After six treatments, the low-level laser therapy group showed a combined reduction in arm circumference of 3.7cm versus 0.2cm in the sham treatment group (p<0.0001). Significantly more subjects in the low-level laser therapy group (N=12; 60%) achieved ≥1.5cm total decrease in upper arm circumference versus sham-treated subjects (N=0; 0%) (p<0.0005). Low-level laser therapy treatment resulted in a combined reduction in arm circumference of 2.2cm after three treatments and 3.7cm after six treatments (for each, p<0.0001) indicating a progressive and cumulative treatment effect. Body mass index remained unchanged for all subjects. A significantly greater number of subjects in the low-level laser therapy treatment group were satisfied with their results (p<0.05), believed their upper arm appearance improved (p<0.0005), and indicated the results exceeded expectations (p<0.05). The treatments were painless and no adverse events were reported. Conclusion: Noninvasive low-level laser therapy is safe, painless, and effective in reducing upper arm circumference and is associated with a high degree of subject satisfaction. PMID:22468172

  5. How much can be learned from populations exposed to low levels of radiation

    SciTech Connect

    Gilbert, E.S.

    1984-05-01

    The assessment of health effects from low-level exposure to radiation is a matter of considerable controversy. Many of the problems in analyzing and interpreting data on populations exposed to low levels of radiation are well illustrated by a current study of the effects on mortality of occupational exposure to radiation at the Hanford plant. The conclusion drawn is that the amount that can be learned from the Hanford population, and other populations exposed to low levels of radiation, is extremely limited. The data are not adequate to determine reliable estimates of risks, or to investigate the appropriateness of various models. Although there are problems in using data from populations exposed at high levels to estimate risks of low level exposure to radiation, the problems in obtaining such estimates directly are even more severe. Thus data from populations such as the Japanese A-bomb survivors and the British ankylosing spondylitis patients must continue to serve as our primary source of information on radiation effects. 27 references, 3 tables. (ACR)

  6. Survey of agents and techniques applicable to the solidification of low-level radioactive wastes

    SciTech Connect

    Fuhrmann, M.; Neilson, R.M. Jr.; Colombo, P.

    1981-12-01

    A review of the various solidification agents and techniques that are currently available or potentially applicable for the solidification of low-level radioactive wastes is presented. An overview of the types and quantities of low-level wastes produced is presented. Descriptions of waste form matrix materials, the wastes types for which they have been or may be applied and available information concerning relevant waste form properties and characteristics follow. Also included are descriptions of the processing techniques themselves with an emphasis on those operating parameters which impact upon waste form properties. The solidification agents considered in this survey include: hydraulic cements, thermoplastic materials, thermosetting polymers, glasses, synthetic minerals and composite materials. This survey is part of a program supported by the United States Department of Energy's Low-Level Waste Management Program (LLWMP). This work provides input into LLWMP efforts to develop and compile information relevant to the treatment and processing of low-level wastes and their disposal by shallow land burial.

  7. Status of the North Carolina/Southeast Compact low-level radioactive waste disposal project

    SciTech Connect

    Walker, C.K.

    1993-03-01

    The Southeast Compact is a sited region for low-level radioactive waste because of the current facility at Barnwell, South Carolina. North Carolina has been designated as the next host state for the compact, and the North Carolina Low-Level Radioactive Waste Management Authority is the agency charged with developing the new facility. Chem-Nuclear Systems, Inc., has been selected by the Authority as its primary site development and operations contractor. This paper will describe the progress currently being made toward the successful opening of the facility in January 1996. The areas to be addressed include site characterization, performance assessment, facility design, public outreach, litigation, finances, and the continued operation of the Barnwell facility.

  8. Characterization of polyurethane systems which contain low levels of free TDI

    SciTech Connect

    Myers, R.L.; Thomas, E.V.

    1995-04-01

    EN-7, EN-8, and EN-9 are polyurethane systems that are used in numerous applications in the Department of Energy complex. These systems contain high levels of toluene diisocyanate (TDI). Currently, TDI is being treated as a suspect human carcinogen within the Department of Energy complex. This report documents the results of a material characterization study of three polyurethane systems that contain low levels of free (potentially airborne) TDI. The characterization has been accomplished by performing a set of statistically designed experiments. The purpose of these experiments is to explore the effects of formulation and cure schedule on various material properties. In general, the material properties (pot life, glass transition temperature, hardness, and tear strength) were relatively insensitive to variation in the cure schedule. On the other hand, variation in curative level had measurable effects on material properties for the polyurethane systems studied. Furthermore, the material properties of the three low-free-TDI polyurethane systems were found to be comparable or superior (for certain curative levels) to commonly-used polyurethane systems. Thus, these low-free-TDI systems appear to be viable candidates for applications where a polyurethane is needed.

  9. Correcting magnetic probe perturbations on current density measurements of current carrying plasmas

    SciTech Connect

    Knoblauch, P.; Raspa, V.; Di Lorenzo, F.; Lazarte, A.; Moreno, C.; Clausse, A.

    2010-09-15

    A method to infer the current density distribution in the current sheath of a plasma focus discharge from a magnetic probe is formulated and then applied to experimental data obtained in a 1.1 kJ device. Distortions on the magnetic probe signal caused by current redistribution and by a time-dependent total discharge current are considered simultaneously, leading to an integral equation for the current density. Two distinct, easy to implement, numerical procedures are given to solve such equation. Experimental results show the coexistence of at least two maxima in the current density structure of a nitrogen sheath.

  10. An expert system for analyzing eddy current measurements

    SciTech Connect

    Levy, A.J.; Oppenlander, J.E.; Brudnoy, D.M.; Englund, J.M.; Loomis, K.C.

    1991-12-31

    A method and apparatus (called DODGER) analyzes eddy current data for heat exchanger tubes or any other metallic object. DODGER uses an expert system to analyze eddy current data by reasoning with uncertainty and pattern recognition. The expert system permits, DODGER to analyze eddy current data intelligently, an obviate operator uncertainty by analyzing the data in a uniform and consistent manner.

  11. A preliminary evaluation of alternatives for treatment of INEL Low-Level Waste and low-level mixed waste

    SciTech Connect

    Smith, T.H.; Roesener, W.S.; Jorgensen-Waters, M.J.; Edinborough, C.R.

    1992-06-01

    The Mixed and Low-Level Waste Treatment Facility (MLLWTF) project was established in 1991 by the US Department of Energy Idaho Field Office to provide treatment capabilities for Idaho National Engineering Laboratory (INEL) low-level mixed waste and low-level waste. This report identifies and evaluates the alternatives for treating that waste. Twelve treatment alternatives, ranging from ``no-action`` to constructing and operating the MLLWTF, are identified and evaluated. Evaluations include facility performance, environmental, safety, institutional, schedule, and rough order-of-magnitude cost comparisons. The performance of each alternative is evaluated against lists of ``musts`` and ``wants.`` Also included is a discussion of other key considerations for decision making. Analysis of results indicated further study is necessary to obtain the best estimate of future waste volumes and characteristics from the expanded INEL Decontamination and Decommissioning Program. It is also recommended that conceptual design begin as scheduled on the MLLWTF, maximum treatment alternative while re-evaluating the waste volume projections.

  12. Measurements of deep currents in the Central North Pacific

    SciTech Connect

    Taft, B.A.; Ramp, S.R.; Dworski, J.G.; Holloway, G.

    1981-03-20

    Two deep arrays of current meters at heights of 1200 and 100 m above the bottom were set under the North Pacific Subtropical Gyre near 30 /sup 0/30'N, 157 /sup 0/45'W; the maximum record length obtained was 19 months. Autospectra show the following characteristics: strong peaks at the M2, S2 tidal frequencies; a broad peak at the diurnal-inertial peak; a spectral gap centered at 0.02 c h/sup -1/; and a regular increase in energy with decreasing frequency below the gap. Rotary components tend to be counterclockwise below 10/sup -2/ c h/sup -1/ and clockwise above the diurnal-inertial frequency. The M2 tidal amplitude ranged between 1.0 and 1.6 cm s/sup -1/; phase relationships suggest that a significant part of the motion is due to internal wave motion at this frequency. Low-pass filtered velocity statistics show the following; evidence of nonstationarity in the variances between the first (9 month) and second (10 month) arrays; significant horizontal variation of mean kinetic energy on scales of 100 km; and time-space averaged eddy kinetic energy is comparable in magnitude to the lowest values measured under the Subtropical Gyre in the western North Atlantic. Currents at 1200 m tended to be greater than at 100 m above the bottom. Spectra of the 100-m records indicate the presence of two peaks at low frequency; a dominant and ubiquitous peak in the 1/105--1/175 c d/sup -1/ frequency band; and a secondary peak, which is shown in three of four moorings, in the 1/58--1/75 c d/sup -1/ freuqncy band. Point estimates of the periods of the peaks give average values of 154 and 67 days. Comparison with subtropic western North Altantic spectra shows that the 'temporal mesoscale' period (approx.150 d) is somewhat higher in the Pacific data and it does not show the dominance of meridional motions observed in the Altantic spectra. Plane wave fits to the 154-day oscillation show the longest wave which closely fits the data has a wave length of 170 km and propagates toward 197

  13. Low-level laser therapy of dentin hypersensitivity: a short-term clinical trial.

    PubMed

    Orhan, Kaan; Aksoy, Umut; Can-Karabulut, Deniz C; Kalender, Atakan

    2011-09-01

    The aim of this study was to evaluate low-level laser therapy in cervical dentin hypersensitivity. A randomized controlled clinical trial was conducted with a total of 64 teeth. Dentin desensitizer and diode laser were applied on the cervical dentin surfaces. Distilled water and placebo laser was used as the placebo groups. The irradiance used was 4 J/cm(2) per treatment site. The baseline measurement of hypersensitivity was made by using visual analog scale (VAS). Twenty-four hours and 7 days after the application of desensitizer, diode laser and placebo groups, a new VAS analysis was conducted for the patients' sensitivity level. The mean pain scores of placebo groups were significantly higher than the desensitizer's and diode laser's mean scores (ANOVA, p < 0.05). The VAS analysis revealed a significant decrease in dentin hypersensitivity in 7 days with the use of the desensitizer and low-level laser therapy and no statistically significant difference was observed between these two treatments (p > 0.05). Although low-level laser and glutaraldehyde containing desensitizer present distinct modes of action, experimental agents caused a significant reduction of dentin hypersensitivity without showing secondary effects, not irritating the pulp or causing pain, not discoloring or staining the teeth, and not irritating the soft tissues at least for a period of 1 week with no drawbacks regarding handling and/or ease of application. Low-level laser therapy and desensitizer application had displayed similar effectiveness in reducing moderate dentin hypersensitivity.

  14. Low level atmospheric sulfur dioxide pollution and childhood asthma

    SciTech Connect

    Tseng, R.Y.; Li, C.K. )

    1990-11-01

    Quarterly analysis (1983-1987) of childhood asthma in Hong Kong from 13,620 hospitalization episodes in relation to levels of pollutants (SO{sub 2}, NO{sub 2}, NO, O{sub 3}, TSP, and RSP) revealed a seasonal pattern of attack rates that correlates inversely with exposure to sulfur dioxide (r = -.52, P less than .05). The same cannot be found with other pollutants. Many factors may contribute to the seasonal variation of asthma attacks. We speculate that prolonged exposure (in terms of months) to low level SO{sub 2} is one factor that might induce airway inflammation and bronchial hyperreactivity and predispose to episodes of asthma.

  15. Nuclear reactor with low-level core coolant intake

    DOEpatents

    Challberg, Roy C.; Townsend, Harold E.

    1993-01-01

    A natural-circulation boiling-water reactor has skirts extending downward from control rod guide tubes to about 10 centimeters from the reactor vessel bottom. The skirts define annular channels about control rod drive housings that extend through the reactor vessel bottom. Recirculating water is forced in through the low-level entrances to these channels, sweeping bottom water into the channels in the process. The sweeping action prevents cooler water from accumulating at the bottom. This in turn minimizes thermal shock to bottom-dwelling components as would occur when accumulated cool water is swept away and suddenly replaced by warmer water.

  16. Alpha low-level stored waste systems design study

    SciTech Connect

    Feizollahi, F.; Teheranian, B.; Quapp, W.J.

    1992-08-01

    The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex`s Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT&E) requirements for each of the three concepts.

  17. Alpha low-level stored waste systems design study

    SciTech Connect

    Feizollahi, F.; Teheranian, B. . Environmental Services Div.); Quapp, W.J. )

    1992-08-01

    The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex's Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT E) requirements for each of the three concepts.

  18. Low level communication management for e-health systems

    NASA Astrophysics Data System (ADS)

    Riva, Guillermo; Zerbini, Carlos; Voos, Javier; Centeno, Carlos; González, Eduardo

    2011-12-01

    The heterogeneity of e-health systems encourages the use of standards such as Health Level 7 (HL7v3) to ensure interoperability. Many actual implementations address this problem by unoptimized high level programming of top-range portable computing platforms. However, this approach could pose excessive demands on battery-powered mid-range terminals. In this work, we propose low-level support for portable HL7v3-compatible embedded systems in order to better exploit their limited processing and communications capabilities. In particular, we present our experience in mobile communication management through two different approaches, which proves the feasibility of this proposal.

  19. Effectiveness of low-level laser on carpal tunnel syndrome

    PubMed Central

    Li, Zhi-Jun; Wang, Yao; Zhang, Hua-Feng; Ma, Xin-Long; Tian, Peng; Huang, Yuting

    2016-01-01

    Abstract Background: Low-level laser therapy (LLLT) has been applied in the treatment of carpal tunnel syndrome (CTS) for an extended period of time without definitive consensus on its effectiveness. This meta-analysis was conducted to evaluate the effectiveness of low-level laser in the treatment of mild to moderate CTS using a Cochrane systematic review. Methods: We conducted electronic searches of PubMed (1966–2015.10), Medline (1966–2015.10), Embase (1980–2015.10), and ScienceDirect (1985–2015.10), using the terms “carpal tunnel syndrome” and “laser” according to the Cochrane Collaboration guidelines. Relevant journals or conference proceedings were searched manually to identify studies that might have been missed in the database search. Only randomized clinical trials were included, and the quality assessments were performed according to the Cochrane systematic review method. The data extraction and analyses from the included studies were conducted independently by 2 reviewers. The results were expressed as the mean difference (MD) with 95% confidence intervals (CI) for the continuous outcomes. Results: Seven randomized clinical trials met the inclusion criteria; there were 270 wrists in the laser group and 261 wrists in the control group. High heterogeneity existed when the analysis was conducted. Hand grip (at 12 weeks) was stronger in the LLLT group than in the control group (MD = 2.04; 95% CI: 0.08–3.99; P = 0.04; I2 = 62%), and there was better improvement in the visual analog scale (VAS) (at 12 weeks) in the LLLT group (MD = 0.97; 95% CI: 0.84–1.11; P < 0.01; I2 = 0%). The sensory nerve action potential (SNAP) (at 12 weeks) was better in the LLLT group (MD = 1.08; 95% CI: 0.44–1.73; P = 0.001; I2 = 0%). However, 1 included study was weighted at >95% in the calculation of these 3 parameters. There were no statistically significant differences in the other parameters between the 2 groups. Conclusion

  20. System for chemically digesting low level radioactive, solid waste material

    DOEpatents

    Cowan, Richard G.; Blasewitz, Albert G.

    1982-01-01

    An improved method and system for chemically digesting low level radioactive, solid waste material having a high through-put. The solid waste material is added to an annular vessel (10) substantially filled with concentrated sulfuric acid. Concentrated nitric acid or nitrogen dioxide is added to the sulfuric acid within the annular vessel while the sulfuric acid is reacting with the solid waste. The solid waste is mixed within the sulfuric acid so that the solid waste is substantilly fully immersed during the reaction. The off gas from the reaction and the products slurry residue is removed from the vessel during the reaction.

  1. Geologic setting of the low-level burial grounds

    SciTech Connect

    Lindsey, K.A.; Jaeger, G.K.; Slate, J.L.; Swett, K.J.; Mercer, R.B.

    1994-10-13

    This report describes the regional and site specific geology of the Hanford Sites low-level burial grounds in the 200 East and West Areas. The report incorporates data from boreholes across the entire 200 Areas, integrating the geology of this area into a single framework. Geologic cross-sections, isopach maps, and structure contour maps of all major geological units from the top of the Columbia River Basalt Group to the surface are included. The physical properties and characteristics of the major suprabasalt sedimentary units also are discussed.

  2. High-temperature strain measurement techniques: Current developments and challenges

    NASA Technical Reports Server (NTRS)

    Lemcoe, M. M.

    1992-01-01

    Since 1987, a very substantial amount of R&D has been conducted in an attempt to develop reliable strain sensors for the measurements of structural strains during ground testing and hypersonic flight, at temperatures up to at least 2000 deg F. Much of the effort has been focused on requirements of the NASP Program. This presentation is limited to the current sensor development work and characterization studies carried out within that program. It is basically an assessment as to where we are now and what remains to be done in the way of technical accomplishments to meet the technical challenges posed by the requirements and constraints established for the NASP Program. The approach for meeting those requirements and constraints has been multi-disciplinary in nature. It was recognized early on that no one sensor could meet all these requirements and constraints, largely because of the large temperature range (cryogenic to at least 2000 deg F) and many other factors, including the most challenging requirement that the sensor system be capable of obtaining valid 'first cycle data'. Present candidate alloys for resistance-type strain gages include Fe-Cr-Al and Pd-Cr. Although they have superior properties regarding withstanding very high temperatures, they exhibit large apparent strains that must either be accounted for or cancelled out by various techniques, including the use of a dual-element, half-bridge dummy gage, or electrical compensation networks. A significant effort is being devoted to developing, refining, and evaluating the effectiveness of those techniques over a broad range in temperature and time. In the quest to obtain first-cycle data, ways must be found to eliminate the need to prestabilize or precondition the strain gage, before it is attached to the test article. It should be noted that present NASP constraints do not permit prestabilization of the sensor, in situ. Gages are currently being 'heat treated' during manufacture in both the wire- and foil

  3. High-temperature strain measurement techniques: Current developments and challenges

    NASA Astrophysics Data System (ADS)

    Lemcoe, M. M.

    1992-09-01

    Since 1987, a very substantial amount of R&D has been conducted in an attempt to develop reliable strain sensors for the measurements of structural strains during ground testing and hypersonic flight, at temperatures up to at least 2000 deg F. Much of the effort has been focused on requirements of the NASP Program. This presentation is limited to the current sensor development work and characterization studies carried out within that program. It is basically an assessment as to where we are now and what remains to be done in the way of technical accomplishments to meet the technical challenges posed by the requirements and constraints established for the NASP Program. The approach for meeting those requirements and constraints has been multi-disciplinary in nature. It was recognized early on that no one sensor could meet all these requirements and constraints, largely because of the large temperature range (cryogenic to at least 2000 deg F) and many other factors, including the most challenging requirement that the sensor system be capable of obtaining valid 'first cycle data'. Present candidate alloys for resistance-type strain gages include Fe-Cr-Al and Pd-Cr. Although they have superior properties regarding withstanding very high temperatures, they exhibit large apparent strains that must either be accounted for or cancelled out by various techniques, including the use of a dual-element, half-bridge dummy gage, or electrical compensation networks. A significant effort is being devoted to developing, refining, and evaluating the effectiveness of those techniques over a broad range in temperature and time. In the quest to obtain first-cycle data, ways must be found to eliminate the need to prestabilize or precondition the strain gage, before it is attached to the test article. It should be noted that present NASP constraints do not permit prestabilization of the sensor, in situ. Gages are currently being 'heat treated' during manufacture in both the wire- and foil

  4. Low-level radioactive waste from commercial nuclear reactors. Volume 1. Recommendations for technology developments with potential to significantly improve low-level radioactive waste management

    SciTech Connect

    Rodgers, B.R.; Jolley, R.L.

    1986-02-01

    The overall task of this program was to provide an assessment of currently available technology for treating commercial low-level radioactive waste (LLRW), to initiate development of a methodology for choosing one technology for a given application, and to identify research needed to improve current treatment techniques and decision methodology. The resulting report is issued in four volumes. Volume 1 provides an executive summary and a general introduction to the four-volume set, in addition to recommendations for research and development (R and D) for low-level radioactive waste (LLRW) treatment. Generic, long-range, and/or high-risk programs identified and prioritized as needed R and D in the LLRW field include: (1) systems analysis to develop decision methodology; (2) alternative processes for dismantling, decontaminating, and decommissioning; (3) ion exchange; (4) incinerator technology; (5) disposal technology; (6) demonstration of advanced technologies; (7) technical assistance; (8) below regulatory concern materials; (9) mechanical treatment techniques; (10) monitoring and analysis procedures; (11) radical process improvements; (12) physical, chemical, thermal, and biological processes; (13) fundamental chemistry; (14) interim storage; (15) modeling; and (16) information transfer. The several areas are discussed in detail.

  5. Treatment options for low-level radiologically contaminated ORNL filtercake

    SciTech Connect

    Lee, Hom-Ti; Bostick, W.D.

    1996-04-01

    Water softening sludge (>4000 stored low level contaminated drums; 600 drums per year) generated by the ORNL Process Waste Treatment Plant must be treated, stabilized, and placed in safe storage/disposal. The sludge is primarily CaCO{sub 3} and is contaminated by low levels of {sup 90}Sr and {sup 137}Cs. In this study, microwave sintering and calcination were evaluated for treating the sludge. The microwave melting experiments showed promise: volume reductions were significant (3-5X), and the waste form was durable with glass additives (LiOH, fly ash). A commercial vendor using surrogate has demonstrated a melt mineralization process that yields a dense monolithic waste form with a volume reduction factor (VR) of 7.7. Calcination of the sludge at 850-900 C yielded a VR of 2.5. Compaction at 4500 psi increased the VR to 4.2, but the compressed form is not dimensionally stable. Addition of paraffin helped consolidate fines and yielded a VR of 3.5. In conclusion, microwave melting or another form of vitrification is likely to be the best method; however for immediate implementation, the calculation/compaction/waxing process is viable.

  6. Greater-than-Class C low-level waste characterization

    SciTech Connect

    Piscitella, R.R.

    1991-12-31

    In 1985, Public Law 99-240 (Low-Level Radioactive Waste Policy Amendments Act of 1985) made the Department of Energy (DOE) responsible for the disposal of greater-than-Class C low-level radioactive waste (GTCC LLW). DOE strategies for storage and disposal of GTCC LLW required characterization of volumes, radionuclide activities, and waste forms. Data from existing literature, disposal records, and original research were used to estimate characteristics, project volumes, and determine radionuclide activities to the years 2035 and 2055. Twenty-year life extensions for 70% of the operating nuclear reactors were assumed to calculate the GTCC LLW available in 2055. The following categories of GTCC LLW were addressed: Nuclear Utilities Waste; Potential Sealed Sources GTCC LLW; DOE-Held Potential GTCC LLW; and Other Generator Waste. It was determined that the largest volume of these wastes, approximately 57%, is generated by nuclear utilities. The Other Generator Waste category contributes approximately 10% of the total GTCC LLW volume projected to the year 2035. DOE-Held Potential GTCC LLW accounts for nearly 33% of all waste projected to the year 2035. Potential Sealed Sources GTCC LLW is less than 0.2% of the total projected volume. The base case total projected volume of GTCC LLW for all categories was 3,250 cubic meters. This was substantially less than previous estimates.

  7. Secondary Low-Level Waste Treatment Strategy Analysis

    SciTech Connect

    D.M. LaRue

    1999-05-25

    The objective of this analysis is to identify and review potential options for processing and disposing of the secondary low-level waste (LLW) that will be generated through operation of the Monitored Geologic Repository (MGR). An estimate of annual secondary LLW is generated utilizing the mechanism established in ''Secondary Waste Treatment Analysis'' (Reference 8.1) and ''Secondary Low-Level Waste Generation Rate Analysis'' (Reference 8.5). The secondary LLW quantities are based on the spent fuel and high-level waste (HLW) arrival schedule as defined in the ''Controlled Design Assumptions Document'' (CDA) (Reference 8.6). This analysis presents estimates of the quantities of LLW in its various forms. A review of applicable laws, codes, and standards is discussed, and a synopsis of those applicable laws, codes, and standards and their impacts on potential processing and disposal options is presented. The analysis identifies viable processing/disposal options in light of the existing laws, codes, and standards, and then evaluates these options in regard to: (1) Process and equipment requirements; (2) LLW disposal volumes; and (3) Facility requirements.

  8. Biphasic Dose Response in Low Level Light Therapy

    PubMed Central

    Huang, Ying-Ying; Chen, Aaron C.-H.; Carroll, James D.; Hamblin, Michael R.

    2009-01-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response. PMID:20011653

  9. Modified sulfur cement solidification of low-level wastes

    SciTech Connect

    Not Available

    1985-10-01

    This topical report describes the results of an investigation on the solidification of low-level radioactive wastes in modified sulfur cement. The work was performed as part of the Waste Form Evaluation Program, sponsored by the US Department of Energy's Low-Level Waste Management Program. Modified sulfur cement is a thermoplastic material developed by the US Bureau of Mines. Processing of waste and binder was accomplished by means of both a single-screw extruder and a dual-action mixing vessel. Waste types selected for this study included those resulting from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste type and method of processing. Property evaluation testing was carried out on laboratory scale specimens in order to compare with waste form performance for other potential matrix materials. Waste form property testing included compressive strength, water immersion, thermal cycling and radionuclide leachability. Recommended waste loadings of 40 wt. % sodium sulfate and boric acid salts and 43 wt. % incinerator ash, which are based on processing and performance considerations, are reported. Solidification efficiencies for these waste types represent significant improvements over those of hydraulic cements. Due to poor waste form performance, incorporation of ion exchange resin waste in modified sulfur cement is not recommended.

  10. Steam Reforming of Low-Level Mixed Waste

    SciTech Connect

    1998-01-01

    Under DOE Contract No. DE-AR21-95MC32091, Steam Reforming of Low-Level Mixed Waste, ThermoChem has successfully designed, fabricated and operated a nominal 90 pound per hour Process Development Unit (PDU) on various low-level mixed waste surrogates. The design construction, and testing of the PDU as well as performance and economic projections for a 500- lb/hr demonstration and commercial system are described. The overall system offers an environmentally safe, non-incinerating, cost-effective, and publicly acceptable method of processing LLMW. The steam-reforming technology was ranked the No. 1 non-incineration technology for destruction of hazardous organic wastes in a study commissioned by the Mixed Waste Focus Area published April 1997.1 The ThermoChem steam-reforming system has been developed over the last 13 years culminating in this successful test campaign on LLMW surrogates. Six surrogates were successfidly tested including a 750-hour test on material simulating a PCB- and Uranium- contaminated solid waste found at the Portsmouth Gaseous Diffusion Plant. The test results indicated essentially total (>99.9999oA) destruction of RCRA and TSCA hazardous halogenated organics, significant levels of volume reduction (> 400 to 1), and retention of radlonuclides in the volume-reduced solids. Cost studies have shown the steam-reforming system to be very cost competitive with more conventional and other emerging technologies.

  11. Biological intrusion of low-level-waste trench covers

    SciTech Connect

    Hakonson, T.E.; Gladney, E.S.

    1981-01-01

    The long-term integrity of low-level waste shallow land burial sites is dependent on the interaction of physical, chemical, and biological factors that modify the waste containment system. Past research on low-level waste shallow land burial methods has emphasized physical (i.e., water infiltration, soil erosion) and chemical (radionuclide leaching) processes that can cause waste site failure and subsequent radionuclide transport. The purpose of this paper is to demonstrate the need to consider biological processes as being potentially important in reducing the integrity of waste burial site cover treatments. Plants and animals not only can transport radionuclides to the ground surface via root systems and soil excavated from the cover profile by animal burrowing activities, but they modify physical and chemical processes within the cover profile by changing the water infiltration rates, soil erosion rates and chemical composition of the soil. One approach to limiting biological intrusion through the waste cover is to apply a barrier within the profile to limit root and animal penetration with depth. Experiments in the Los Alamos Experimental Engineered Test Facility were initiated to develop and evaluate biological barriers that are effective in minimizing intrusion into waste trenches. The experiments that are described employ four different candidate barrier materials of geologic origin. Experimental variables that will be evaluated, in addition to barrier type, are barrier depth and soil overburden depth. The rate of biological intrusion through the various barrier materials is being evaluated through the use of activatable stable tracers.

  12. Association of hypothyroidism with low-level arsenic exposure in rural West Texas

    SciTech Connect

    Gong, Gordon; Basom, Janet; Mattevada, Sravan; Onger, Frederick

    2015-04-15

    It has been reported recently that a higher airborne arsenic level was correlated with higher urinary arsenic concentration and lower serum thyroxin level among urban policemen and rural highway workmen in Italy. The current study was to determine whether exposure to low-level arsenic groundwater (2–22 µg/L) is associated with hypothyroidism among 723 participants (118 male and 267 female Hispanics; 108 male and 230 female non-Hispanic whites, NHW) living in rural West Texas counties. Arsenic and iodine levels in their groundwater used for drinking and or cooking were estimated by the inverse distance weighted (IDW) interpolation technique. Groundwater arsenic was ≥8 µg/L in 36% of the subjects' wells while iodine concentration was <1 µg/L in 91% of their wells. Logistic regression analysis showed that arsenic in groundwater ≥8 µg/L and cumulative arsenic exposure (groundwater arsenic concentration multiplied by the number of years living in the current address) but not groundwater iodine concentration were significant predictors for hypothyroidism among Hispanics (p<0.05) but not NHW after adjusting for covariates such as age, gender, annual household income and health insurance coverage. The ethnic difference may be due to a marginally higher percentage of Hispanics (p=0.0622) who lived in areas with groundwater arsenic ≥8 µg/L compared with NHW. The prevalence of hypothyroidism was significantly higher in Hispanics or NHW of this rural cohort than the national prevalence. Measures should be taken to reduce arsenic in drinking water in order to prevent hypothyroidism in rural areas. - Highlights: • We determined if arsenic exposure is associated with hypothyroidism in rural Texas. • Groundwater arsenic level is associated with hypothyroidism among Hispanics only. • The rate of hypothyroidism in rural Texas was higher than the US general population.

  13. Radiographic abnormalities in Vermont granite workers exposed to low levels of granite dust.

    PubMed

    Graham, W G; Ashikaga, T; Hemenway, D; Weaver, S; O'Grady, R V

    1991-12-01

    The issue of whether low levels of granite dust exposure lead to radiographic abnormalities after a lifetime of exposure has not been settled. In 1983, we carried out a radiographic survey of the Vermont granite industry, consisting of quarry and stone shed workers who had been exposed to the low dust levels prevailing in the industry since 1938 to 1940. Films were read by three "B" readers, using the ILO classification system, which requires the identification of both rounded and irregular opacities, as well as combinations of both. X-ray films were taken of 972 workers, out of a total work force of approximately 1,400. Of these films, 28 (3 percent) were interpreted by either two or three of the three readers as showing abnormalities consistent with pneumoconiosis. Only seven films (or 0.7 percent of the entire cohort) showed nodular or rounded opacities of the type typically seen in uncomplicated silicosis. The remainder of the abnormal x-ray films showed irregular opacities, largely in the lower lung zones, which are of uncertain significance, but may be related to heavy cigarette smoking and aging, and possibly dust inhalation. In addition, total gravimetric dust concentrations in the workplace were measured; 417 respirable-size mass samples showed concentrations of 601 micrograms/cu m +/- 368 micrograms/cu m. Using previously published estimates of 10 percent quartz in granite dust, the average quartz concentration was 60 micrograms/cu m. Twelve percent of the samples exceeded 100 micrograms/cu m, the current OSHA standard for quartz. We conclude that control of quartz exposure in the Vermont granite industry to levels which are on average less than the current OSHA standard has essentially eliminated definite radiographic changes of silicosis. The significance of the irregular opacities in the lower lung zones seen on a majority of the 28 x-ray films judged to be abnormal is not clear.

  14. Association of hypothyroidism with low-level arsenic exposure in rural West Texas.

    PubMed

    Gong, Gordon; Basom, Janet; Mattevada, Sravan; Onger, Frederick

    2015-04-01

    It has been reported recently that a higher airborne arsenic level was correlated with higher urinary arsenic concentration and lower serum thyroxin level among urban policemen and rural highway workmen in Italy. The current study was to determine whether exposure to low-level arsenic groundwater (2-22µg/L) is associated with hypothyroidism among 723 participants (118 male and 267 female Hispanics; 108 male and 230 female non-Hispanic whites, NHW) living in rural West Texas counties. Arsenic and iodine levels in their groundwater used for drinking and or cooking were estimated by the inverse distance weighted (IDW) interpolation technique. Groundwater arsenic was ≥8µg/L in 36% of the subjects' wells while iodine concentration was <1µg/L in 91% of their wells. Logistic regression analysis showed that arsenic in groundwater ≥8µg/L and cumulative arsenic exposure (groundwater arsenic concentration multiplied by the number of years living in the current address) but not groundwater iodine concentration were significant predictors for hypothyroidism among Hispanics (p<0.05) but not NHW after adjusting for covariates such as age, gender, annual household income and health insurance coverage. The ethnic difference may be due to a marginally higher percentage of Hispanics (p=0.0622) who lived in areas with groundwater arsenic ≥8µg/L compared with NHW. The prevalence of hypothyroidism was significantly higher in Hispanics or NHW of this rural cohort than the national prevalence. Measures should be taken to reduce arsenic in drinking water in order to prevent hypothyroidism in rural areas.

  15. Mixed and low-level waste treatment facility project. Volume 3, Waste treatment technologies (Draft)

    SciTech Connect

    Not Available

    1992-04-01

    The technology information provided in this report is only the first step toward the identification and selection of process systems that may be recommended for a proposed mixed and low-level waste treatment facility. More specific information on each technology will be required to conduct the system and equipment tradeoff studies that will follow these preengineering studies. For example, capacity, maintainability, reliability, cost, applicability to specific waste streams, and technology availability must be further defined. This report does not currently contain all needed information; however, all major technologies considered to be potentially applicable to the treatment of mixed and low-level waste are identified and described herein. Future reports will seek to improve the depth of information on technologies.

  16. Conceptual Design Report for the Remote-Handled Low-Level Waste Disposal Project

    SciTech Connect

    David Duncan

    2011-05-01

    This conceptual design report addresses development of replacement remote-handled low-level waste disposal capability for the Idaho National Laboratory. Current disposal capability at the Radioactive Waste Management Complex is planned until the facility is full or until it must be closed in preparation for final remediation (approximately at the end of Fiscal Year 2017). This conceptual design report includes key project assumptions; design options considered in development of the proposed onsite disposal facility (the highest ranked alternative for providing continued uninterrupted remote-handled low level waste disposal capability); process and facility descriptions; safety and environmental requirements that would apply to the proposed facility; and the proposed cost and schedule for funding, design, construction, and operation of the proposed onsite disposal facility.

  17. Conceptual Design Report for Remote-Handled Low-Level Waste Disposal Facility

    SciTech Connect

    Lisa Harvego; David Duncan; Joan Connolly; Margaret Hinman; Charles Marcinkiewicz; Gary Mecham

    2010-10-01

    This conceptual design report addresses development of replacement remote-handled low-level waste disposal capability for the Idaho National Laboratory. Current disposal capability at the Radioactive Waste Management Complex is planned until the facility is full or until it must be closed in preparation for final remediation (approximately at the end of Fiscal Year 2017). This conceptual design report includes key project assumptions; design options considered in development of the proposed onsite disposal facility (the highest ranked alternative for providing continued uninterrupted remote-handled low level waste disposal capability); process and facility descriptions; safety and environmental requirements that would apply to the proposed facility; and the proposed cost and schedule for funding, design, construction, and operation of the proposed onsite disposal facility.

  18. Conceptual Design Report for the Remote-Handled Low-Level Waste Disposal Project

    SciTech Connect

    Lisa Harvego; David Duncan; Joan Connolly; Margaret Hinman; Charles Marcinkiewicz; Gary Mecham

    2011-03-01

    This conceptual design report addresses development of replacement remote-handled low-level waste disposal capability for the Idaho National Laboratory. Current disposal capability at the Radioactive Waste Management Complex is planned until the facility is full or until it must be closed in preparation for final remediation (approximately at the end of Fiscal Year 2017). This conceptual design report includes key project assumptions; design options considered in development of the proposed onsite disposal facility (the highest ranked alternative for providing continued uninterrupted remote-handled low level waste disposal capability); process and facility descriptions; safety and environmental requirements that would apply to the proposed facility; and the proposed cost and schedule for funding, design, construction, and operation of the proposed onsite disposal facility.

  19. Comprehensive low-level radioactive waste management plan for the Commonwealth of Kentucky

    SciTech Connect

    Carr, R.M.; Mills, D.; Perkins, C.; Riddle, R.

    1984-03-01

    Part I of the Comprehensive Low-Level Radioactive Waste Management Plan for the Commonwealth of Kentucky discusses the alternatives that have been examined to manage the low-level radioactive waste currently generated in the state. Part II includes a history of the commercial operation of the Maxey Flats Nuclear Waste Disposal Site in Fleming County, Kentucky. The reasons for closure of the facility by the Human Resources Cabinet, the licensing agency, are identified. The site stabilization program managed by the Natural Resources and Environmental Protection Cabinet is described in Chapter VI. Future activities to be conducted at the Maxey Flats Disposal Site will include site stabilization activities, routine operations and maintenance, and environmental monitoring programs as described in Chapter VII.

  20. Melter technology evaluation for vitrification of Hanford Site low-level waste

    SciTech Connect

    Wilson, C.N.; Burgard, K.C.; Weber, E.T.; Brown, N.R.

    1995-04-01

    The current plan at the Hanford Site, in accordance with the Tri-Party Agreement among Washington State, the US Environmental Protection Agency, and the US Department of Energy, is to convert the low-level tank waste fraction into a silicate glass. The low-level waste will be composed primarily of sodium nitrate and nitrite salts concentrated in a highly alkaline aqueous solution. The capability to process up to 200 metric tons/day off glass will be established to produce an estimated 210,000 m{sup 3} for onsite disposal. A program to test and evaluate high-capacity melter technologies is in progress. Testing performed by seven different industrial sources using Joule heating, combustion, plasma, and carbon arc melters is described.

  1. Wintertime current meter measurements from the East China Sea

    SciTech Connect

    Trump, C.L.; Burt, W.V.

    1981-09-01

    An array of three current meters were anchored on the continental shelf of the East China Sea during the last half of February 1975 as part of the Japanese Air Mass Transformation Experiment, AMTEX-75. The results indicate that the currents are dominated by the rotational semidiurnal M/sub 2/ tidal component superimposed on a slow mean drift to the northeast. Differences in direction of several days duration between two of the current meters suggest the presence of transient mesoscale eddies or meanders in the flow regime.

  2. Evaluation of Acoustic Doppler Current Profiler measurements of river discharge

    USGS Publications Warehouse

    Morlock, S.E.

    1996-01-01

    The standard deviations of the ADCP measurements ranged from approximately 1 to 6 percent and were generally higher than the measurement errors predicted by error-propagation analysis of ADCP instrument performance. These error-prediction methods assume that the largest component of ADCP discharge measurement error is instrument related. The larger standard deviations indicate that substantial portions of measurement error may be attributable to sources unrelated to ADCP electronics or signal processing and are functions of the field environment.

  3. Direct measurements of World Ocean tidal currents with surface drifters

    NASA Astrophysics Data System (ADS)

    Poulain, Pierre-Marie; Centurioni, Luca

    2015-10-01

    Velocities of surface drifters are analyzed to study tidal currents throughout the World Ocean. The global drifter data set spanning the period 1979-2013 is used to describe the geographical structure of the surface tidal currents at global scale with a resolution of 2°. Harmonic analysis is performed with two semidiurnal, two diurnal, and four inferred tidal constituents. Tidal current characteristics (amplitude of semimajor axis, rotary coefficient, tidal ellipse inclination, and Greenwich phase) are mapped over the World Ocean from direct observations. The M2 currents dominate on all the shallow continental shelves with magnitude exceeding 60 cm/s. They are also substantial (4-5 cm/s) over the main deep topographic features such as the Mid-Atlantic Ridge, the Southwest Indian Ridge, and the Mariana Ridge. The S2 currents have amplitudes typically half the size of the M2 currents, with a maximum of about 30 cm/s. The K1 and O1 currents are important in many shallow seas. They are large in the vicinity of the turning latitudes near 30°N/S where they merge with inertial motions of the same frequency. They are also substantial in the South China Sea and Philippine Sea. Maps of rotary coefficients indicate that all tidal motions are essentially clockwise (anticlockwise) in the Northern (Southern) Hemisphere. The rotary coefficient of the tidal currents is compared with the theory of freely and meridionally propagating baroclinic inertia-gravity waves. The Greenwich phase of the M2 constituent has large-scale coherent propagation patterns which could be interpreted as the propagation of the barotropic tide.

  4. Measuring the Kuroshio Current with ocean acoustic tomography.

    PubMed

    Taniguchi, Naokazu; Huang, Chen-Fen; Kaneko, Arata; Liu, Cho-Teng; Howe, Bruce M; Wang, Yu-Huai; Yang, Yih; Lin, Ju; Zhu, Xiao-Hua; Gohda, Noriaki

    2013-10-01

    Ocean current profiling using ocean acoustic tomography (OAT) was conducted in the Kuroshio Current southeast of Taiwan from August 20 to September 15, 2009. Sound pulses were transmitted reciprocally between two acoustic stations placed near the underwater sound channel axis and separated by 48 km. Based on the result of ray simulation, the received signals are divided into multiple ray groups because it is difficult to resolve the ray arrivals for individual rays. The average differential travel times from these ray groups are used to reconstruct the vertical profiles of currents. The currents are estimated with respect to the deepest water layer via two methods: An explicit solution and an inversion with regularization. The strong currents were confined to the upper 200 m and rapidly weakened toward 500 m in depth. Both methods give similar results and are consistent with shipboard acoustic Doppler current profiler results in the upper 150 m. The observed temporal variation demonstrates a similar trend to the prediction from the Hybrid Coordinate Ocean Model. PMID:24116522

  5. Development studies for the treatment of ORNL low-level liquid waste

    SciTech Connect

    Campbell, D.O.; Lee, D.D.; Dillow, T.A.

    1991-11-01

    An experimental program is under way to investigate potential separation methods for application to specific problems relating to the management of low-level liquid wastes (LLLWs) at ORNL. This report summarizes experimental results that were acquired during fiscal year 1990 and have not been previously reported elsewhere. Measurements are presented for cesium and strontium removal from simulated high-salt waste compositions, using both inorganic ion- exchange sorbents and organic ion-exchange resins, and for one experiment with actual LLLW supernate solution from Melton Valley Storage Tank W-26, using inorganic sorbents. The purpose of the study was to acquire an extensive data base to support the development of flowsheets for decontamination of the LLLW currently stored at ORNL. Experimental measurements with inorganic ion exchangers focused on batch separations of cesium using several transition-metal hexacyanoferrate(2) compositions (ferrocyanides) and of strontium using titanium oxide-based sorbents. Cesium distribution coefficients in the range of 1 {times} 10{sup 6} were generally observed with nickel and cobalt ferrocyanides at pH values {le}11, yielding DFs of about 100 with 100 ppm sorbent in a single-stage batch separation. Most organic ion-exchange resins are not very effective for cesium removal from such high salt concentrations, but a new resorcinol-based resin developed at the Savannah River Site was found to be considerably superior to any other such material tested. Several chelating resins were effective for removing strontium from the waste simulants. An ion-exchange column test successfully demonstrated the simultaneous removal of both cesium and strontium from a waste simulant solution.

  6. Oestrogen, ocular function and low-level vision: a review.

    PubMed

    Hutchinson, Claire V; Walker, James A; Davidson, Colin

    2014-11-01

    Over the past 10 years, a literature has emerged concerning the sex steroid hormone oestrogen and its role in human vision. Herein, we review evidence that oestrogen (oestradiol) levels may significantly affect ocular function and low-level vision, particularly in older females. In doing so, we have examined a number of vision-related disorders including dry eye, cataract, increased intraocular pressure, glaucoma, age-related macular degeneration and Leber's hereditary optic neuropathy. In each case, we have found oestrogen, or lack thereof, to have a role. We have also included discussion of how oestrogen-related pharmacological treatments for menopause and breast cancer can impact the pathology of the eye and a number of psychophysical aspects of vision. Finally, we have reviewed oestrogen's pharmacology and suggest potential mechanisms underlying its beneficial effects, with particular emphasis on anti-apoptotic and vascular effects.

  7. Low-level stored waste inspection using mobile robots

    SciTech Connect

    Byrd, J.S.; Pettus, R.O.

    1996-06-01

    A mobile robot inspection system, ARIES (Autonomous Robotic Inspection Experimental System), has been developed for the U.S. Department of Energy to replace human inspectors in the routine, regulated inspection of radioactive waste stored in drums. The robot will roam the three-foot aisles of drums, stacked four high, making decisions about the surface condition of the drums and maintaining a database of information about each drum. A distributed system of onboard and offboard computers will provide versatile, friendly control of the inspection process. This mobile robot system, based on a commercial mobile platform, will improve the quality of inspection, generate required reports, and relieve human operators from low-level radioactive exposure. This paper describes and discusses primarily the computer and control processes for the system.

  8. Overview of resuspension model: application to low level waste management

    SciTech Connect

    Healy, J.W.

    1980-01-01

    Resuspension is one of the potential pathways to man for radioactive or chemical contaminants that are in the biosphere. In waste management, spills or other surface contamination can serve as a source for resuspension during the operational phase. After the low-level waste disposal area is closed, radioactive materials can be brought to the surface by animals or insects or, in the long term, the surface can be removed by erosion. Any of these methods expose the material to resuspension in the atmosphere. Intrusion into the waste mass can produce resuspension of potential hazard to the intruder. Removal of items from the waste mass by scavengers or archeologists can result in potential resuspension exposure to others handling or working with the object. The ways in which resuspension can occur are wind resuspension, mechanical resuspension and local resuspension. While methods of predicting exposure are not accurate, they include the use of the resuspension factor, the resuspension rate and mass loading of the air.

  9. Screening Experiments for Removal of Low-Level Tritiated Water

    SciTech Connect

    Kim, Yun Mi; Baney, Ronald; Powers, Kevin; Koopman, Ben; Tulenko, James

    2005-03-15

    Screening experiments for low levels of tritiated water (HTO) remediation based upon selective adsorption/desorption mechanisms utilizing equilibrium isotope effects have been carried out. Several organic and inorganic high surface area materials were investigated to assess their ability to selectively adsorb low concentrations of HTO. Ion-exchange resins with cation functionalities, chitosan, sodium alginate, and several inorganic media modified with metal cations exhibited promising results. Biomaterials, for example, chitosan and modified alginate, demonstrated positive results. Based on the literature and our preliminary testing, we postulate four possible mechanisms for selected tritium adsorption: hydrogen ion exchange, HTO coordination with surface cation sites, hydrogen bonding to surface basic sites, and secondary hydrogen bonding (structural water) in fine pores.

  10. Low-level light therapy (LLLT) for cosmetics and dermatology

    NASA Astrophysics Data System (ADS)

    Sawhney, Mossum K.; Hamblin, Michael R.

    2014-02-01

    Over the last few years, low-level laser (light) therapy (LLLT) has been demonstrated to be beneficial to the field of aesthetic medicine, specifically aesthetic dermatology. LLLT encompasses a broad spectrum of procedures, primarily cosmetic, which provide treatment options for a myriad of dermatological conditions. Dermatological disorders involving inflammation, acne, scars, aging and pigmentation have been investigated with the assistance of animal models and clinical trials. The most commercially successful use of LLLT is for managing alopecia (hair loss) in both men and women. LLLT also seems to play an influential role in procedures such as lipoplasty and liposuction, allowing for noninvasive and nonthermal methods of subcutaneous fat reduction. LLLT offers a means to address such conditions with improved efficacy versatility and no known side-effects; however comprehensive literature reports covering the utility of LLLT are scarce and thus the need for coverage arises.

  11. Low level laser therapy on injured rat muscle

    NASA Astrophysics Data System (ADS)

    Mantineo, M.; Pinheiro, J. P.; Morgado, A. M.

    2013-06-01

    Although studies show the clinical effectiveness of low level laser therapy (LLLT) in facilitating the muscle healing process, scientific evidence is still required to prove the effectiveness of LLLT and to clarify the cellular and molecular mechanisms triggered by irradiation. Here we evaluate the effect of different LLLT doses, using continuous illumination (830 nm), in the treatment of inflammation induced in the gastrocnemius muscle of Wistar rats, through the quantification of cytokines in systemic blood and histological analysis of muscle tissue. We verified that all applied doses produce an effect on reducing the number of inflammatory cells and the concentration of pro-inflammatory TNF-α and IL-1β cytokines. The best results were obtained for 40 mW. The results may suggest a biphasic dose response curve.

  12. Characteristics of low-level radioactive decontamination waste

    SciTech Connect

    Akers, D.W.; McConnell, J.W. Jr.; Morcos, N. )

    1993-02-01

    This document addresses the work performed during fiscal year 1992 at the Idaho National Engineering Laboratory by the Low-Level Radioactive Waste -- Decontamination Waste Program (FIN A6359), which is funded by the US Nuclear Regulatory Commission. The program evaluates the physical stability and leachability of solidified waste streams generated in the decontamination process of primary coolant systems in operating nuclear power stations. The data in this document include the chemical composition and characterization of waste streams from Peach Bottom Atomic Power Station Unit 3 and from Nine Mile Point Nuclear Plant Unit 1. The results of compressive strength testing on immersed and unimmersed solidified waste-form specimens from peach Bottom, and the results of leachate analysis are addressed. Cumulative fractional release rates and leachability indexes of those specimens were calculated and are included in this report.

  13. WRAP low level waste (LLW) glovebox acceptance test report

    SciTech Connect

    Leist, K.J.

    1998-02-17

    In June 28, 1997, the Low Level Waste (LLW) glovebox was tested using glovebox acceptance test procedure 13031A-85. The primary focus of the glovebox acceptance test was to examine control system interlocks, display menus, alarms, and operator messages. Limited mechanical testing involving the drum ports, hoists, drum lifter, compacted drum lifter, drum tipper, transfer car, conveyors, lidder/delidder device and the supercompactor were also conducted. As of November 24, 1997, 2 of the 131 test exceptions that affect the LLW glovebox remain open. These items will be tracked and closed via the WRAP Master Test Exception Database. As part of Test Exception resolution/closure the responsible individual closing the Test Exception performs a retest of the affected item(s) to ensure the identified deficiency is corrected, and, or to test items not previously available to support testing. Test Exceptions are provided as appendices to this report.

  14. Luminous fabric devices for wearable low-level light therapy

    PubMed Central

    Shen, Jing; Chui, Chunghin; Tao, Xiaoming

    2013-01-01

    In this paper, a flexible luminous fabric device was developed and investigated for wearable three-dimensionally fitted low-level light therapy. The fabric device exhibited excellent optical and thermal properties. Its optical power density and operating temperature were stable during usage for 10 hours. In vitro experiments demonstrated a significant increase in collagen production in human fibroblast irradiated by the fabric device, compared with the fibroblast without light irradiation. A series of tests were conducted for the safety of the fabric for human skin contact according to ISO standard ISO 10993-1:2003. The results showed that there was no potential hazard when the luminous fabrics were in direct contact with human skin. PMID:24409391

  15. Mercury's Tail Current Sheet from MESSENGER Magnetic Field Measurements

    NASA Astrophysics Data System (ADS)

    Al Asad, M.; Johnson, C. L.; Philpott, L. C.; Anderson, B. J.; Korth, H.; Slavin, J. A.; Solomon, S. C.

    2014-12-01

    We have estimated the spatial variations in the position and average thickness of Mercury's magnetospheric tail current sheet from orbital magnetic field data collected by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. We have investigated the changes in these average properties with varying solar wind conditions and magnetospheric activity. The time-averaged thickness of the current sheet was obtained from superposed epoch analysis (SEA) of the 1-s-averaged vector magnetic field data within ± 10 min of the identified magnetic equator position at different down-tail distances. The average thickness was then estimated from a given SEA by identifying the time interval during which the field completed a rotation from the sunward to the anti-sunward direction, or vice versa, accompanied by a depression in the field magnitude. We have found that the current sheet has a thickness of ~0.8 RM (where RM is Mercury's radius, or 2440 km) close to the planet (~ 1.1 RM) and thins to ~0.2 RM in the far tail region (~2.8 RM). We examined individual orbits to catalogue the existence and number of current sheet crossings encountered on each orbit. These data allow us to (1) determine whether the thickness obtained from the SEA is an actual thickness or an apparent thickness controlled by rapid motions of the current sheet, and (2) estimate the statistical likelihood of observing the current sheet as a function of down-tail distance. For example, some magnetically quiet orbits that cross the magnetic equator at down-tail distances greater than 2 RM do not record a current sheet crossing and appear to cross closed field lines in the vicinity of the magnetic equator, even though they lie in a region in which the tail current sheet is usually observed. This result suggests that the inner (near-planet) edge of the current sheet is not stationary but may move anti-sunward (or sunward) under quiet (or active) magnetospheric conditions.

  16. ADCP measurements of gravity currents in the Chicago River, Illinois

    USGS Publications Warehouse

    Garcia, C.M.; Oberg, K.; Garcia, M.H.

    2007-01-01

    A unique set of observations of stratified flow phenomena in the Chicago River was made using an upward-looking acoustic Doppler current profiler (ADCP) during the period November 20, 2003 to February 1, 2004. Water density differences between the Chicago River and its North Branch (NB) seem to be responsible for the development of gravity currents. With the objective of characterizing the occurrence, frequency, and evolution of such currents, the ADCP was configured to continuously collect high-resolution water velocity and echo intensity profiles in the Chicago River at Columbus Drive. During the observation period, 28 gravity current events were identified, lasting a total of 77% of the time. Sixteen of these events were generated by underflows from the NB and 12 of these events were generated by overflows from the NB. On average, the duration of the underflow and overflow events was 52.3 and 42.1 h, respectively. A detailed analysis of one underflow event, which started on January 7, 2004, and lasted about 65h, was performed. This is the first time that ADCP technology has been used to continuously monitor gravity currents in a river. ?? 2007 ASCE.

  17. Decontamination processes for low level radioactive waste metal objects

    SciTech Connect

    Longnecker, E.F.; Ichikawa, Sekigo; Kanamori, Osamu

    1996-12-31

    Disposal and safe storage of contaminated nuclear waste is a problem of international scope. Although the greatest volume of such waste is concentrated in the USA and former Soviet Union, Western Europe and Japan have contaminated nuclear waste requiring attention. Japan`s radioactive nuclear waste is principally generated at nuclear power plants since it has no nuclear weapons production. However, their waste reduction, storage and disposal problems may be comparable to that of the USA on an inhabited area basis when consideration is given to population density where Japan`s population, half that of the USA, lives in an area slightly smaller than that of California`s. If everyone`s backyard was in California, the USA might have insoluble radioactive waste reduction, storage and disposal problems. Viewing Japan`s contaminated nuclear waste as a national problem requiring solutions, as well as an economic opportunity, Morikawa began research and development for decontaminating low level radioactive nuclear waste seven years ago. As engineers and manufacturers of special machinery for many years Morikawa brings special electro/mechanical/pneumatic Skills and knowledge to solving these unique problems. Genden Engineering Services and Construction Company (GESC), an affiliate of Japan Atomic Power Company, recently joined with Morikawa in this R&D effort to decontaminate low level radioactive nuclear waste (LLW) and to substantially reduce the volume of such nuclear waste requiring long term storage. This paper will present equipment with both mechanical and chemical processes developed over these several years by Morikawa and most recently in cooperation with GESC.

  18. Costs of mixed low-level waste stabilization options

    SciTech Connect

    Schwinkendorf, W.E.; Cooley, C.R.

    1998-03-01

    Selection of final waste forms to be used for disposal of DOE`s mixed low-level waste (MLLW) depends on the waste form characteristics and total life cycle cost. In this paper the various cost factors associated with production and disposal of the final waste form are discussed and combined to develop life-cycle costs associated with several waste stabilization options. Cost factors used in this paper are based on a series of treatment system studies in which cost and mass balance analyses were performed for several mixed low-level waste treatment systems and various waste stabilization methods including vitrification, grout, phosphate bonded ceramic and polymer. Major cost elements include waste form production, final waste form volume, unit disposal cost, and system availability. Production of grout costs less than the production of a vitrified waste form if each treatment process has equal operating time (availability) each year; however, because of the lower volume of a high temperature slag, certification and handling costs and disposal costs of the final waste form are less. Both the total treatment cost and life cycle costs are higher for a system producing grout than for a system producing high temperature slag, assuming equal system availability. The treatment costs decrease with increasing availability regardless of the waste form produced. If the availability of a system producing grout is sufficiently greater than a system producing slag, then the cost of treatment for the grout system will be less than the cost for the slag system, and the life cycle cost (including disposal) may be less depending on the unit disposal cost. Treatment and disposal costs will determine the return on investment in improved system availability.

  19. Shallow land burial of low-level radioactive waste

    SciTech Connect

    Cannon, J.B.; Jacobs, D.G.; Lee, D.W.; Gilmore, C.C.; Ketelle, R.H.; Kornegay, F.C.; Roop, R.D.; Staub, W.P.; Stratton, L.E.; Thoma, R.E.

    1986-02-01

    The performance objectives included in regulations for disposal of low-level radioactive waste (10 CFR 61 for commercial waste and DOE Order 5820.2 for defense waste) are generic principles that generate technical requirements which must be factored into each phase of the development and operation of a shallow land burial facility. These phases include a determination of the quantity and characteristics of the waste, selection of a site and appropriate facility design, use of sound operating practices, and closure of the facility. The collective experience concerning shallow land burial operations has shown that achievement of the performance objectives (specifically, waste isolation and radionuclide containment) requires a systems approach, factoring into consideration the interrelationships of the phases of facility development and operation and their overall impact on performance. This report presents the technical requirements and procedures for the development and operation of a shallow land burial facility for low-level radioactive waste. The systems approach is embodied in the presentation. The report is not intended to be an instruction manual; rather, emphasis is placed on understanding the technical requirements and knowing what information and analysis are needed for making informed choices to meet them. A framework is developed for using the desired site characteristics to locate potentially suitable sites. The scope of efforts necessary for characterizing a site is then described and the range of techniques available for site characterization is identified. Given the natural features of a site, design options for achieving the performance objectives are discussed, as are the operating practices, which must be compatible with the design. Site closure is presented as functioning to preserve the containment and isolation provided at earlier stages of the development and operation of the facility.

  20. Incineration of Low Level Radioactive Vegetation for Waste Volume Reduction

    SciTech Connect

    Malik, N.P.S.; Rucker, G.G.; Looper, M.G.

    1995-03-01

    The DOE changing mission at Savannah River Site (SRS) are to increase activities for Waste Management and Environmental Restoration. There are a number of Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) locations that are contaminated with radioactivity and support dense vegetation, and are targeted for remediation. Two such locations have been studied for non-time critical removal actions under the National Contingency Plan (NCP). Both of these sites support about 23 plant species. Surveys of the vegetation show that radiation emanates mainly from vines, shrubs, and trees and range from 20,000 to 200,000 d/m beta gamma. Planning for removal and disposal of low-level radioactive vegetation was done with two principal goals: to process contaminated vegetation for optimum volume reduction and waste minimization, and for the protection of human health and environment. Four alternatives were identified as candidates for vegetation removal and disposal: chipping the vegetation and packing in carbon steel boxes (lined with synthetic commercial liners) and disposal at the Solid Waste Disposal Facility at SRS; composting the vegetation; burning the vegetation in the field; and incinerating the vegetation. One alternative `incineration` was considered viable choice for waste minimization, safe handling, and the protection of the environment and human health. Advantages and disadvantages of all four alternatives considered have been evaluated. For waste minimization and ultimate disposal of radioactive vegetation incineration is the preferred option. Advantages of incineration are that volume reduction is achieved and low-level radioactive waste are stabilized. For incineration and final disposal vegetation will be chipped and packed in card board boxes and discharged to the rotary kiln of the incinerator. The slow rotation and longer resident time in the kiln will ensure complete combustion of the vegetative material.

  1. Tethered acoustic doppler current profiler platforms for measuring streamflow

    USGS Publications Warehouse

    Rehmel, Michael S.; Stewart, James A.; Morlock, Scott E.

    2003-01-01

    A tethered-platform design with a trimaran hull and 900-megahertz radio modems is now commercially available. Continued field use has resulted in U.S. Geological Survey procedures for making tethered-platform discharge measurements, including methods for tethered-boat deployment, moving-bed tests, and measurement of edge distances.

  2. Effects of low-level blast exposure on the nervous system: is there really a controversy?

    PubMed

    Elder, Gregory A; Stone, James R; Ahlers, Stephen T

    2014-01-01

    High-pressure blast waves can cause extensive CNS injury in human beings. However, in combat settings, such as Iraq and Afghanistan, lower level exposures associated with mild traumatic brain injury (mTBI) or subclinical exposure have been much more common. Yet controversy exists concerning what traits can be attributed to low-level blast, in large part due to the difficulty of distinguishing blast-related mTBI from post-traumatic stress disorder (PTSD). We describe how TBI is defined in human beings and the problems posed in using current definitions to recognize blast-related mTBI. We next consider the problem of applying definitions of human mTBI to animal models, in particular that TBI severity in human beings is defined in relation to alteration of consciousness at the time of injury, which typically cannot be assessed in animals. However, based on outcome assessments, a condition of "low-level" blast exposure can be defined in animals that likely approximates human mTBI or subclinical exposure. We review blast injury modeling in animals noting that inconsistencies in experimental approach have contributed to uncertainty over the effects of low-level blast. Yet, animal studies show that low-level blast pressure waves are transmitted to the brain. In brain, low-level blast exposures cause behavioral, biochemical, pathological, and physiological effects on the nervous system including the induction of PTSD-related behavioral traits in the absence of a psychological stressor. We review the relationship of blast exposure to chronic neurodegenerative diseases noting the paradoxical lowering of Abeta by blast, which along with other observations suggest that blast-related TBI is pathophysiologically distinct from non-blast TBI. Human neuroimaging studies show that blast-related mTBI is associated with a variety of chronic effects that are unlikely to be explained by co-morbid PTSD. We conclude that abundant evidence supports low-level blast as having long

  3. Measurement of calcium transients and slow calcium current in myotubes

    PubMed Central

    1994-01-01

    The purpose of this study was to characterize excitation-contraction (e- c) coupling in myotubes for comparison with e-c coupling of adult skeletal muscle. The whole cell configuration of the patch clamp technique was used in conjunction with the calcium indicator dye Fluo-3 to study the calcium transients and slow calcium currents elicited by voltage clamp pulses in cultured myotubes obtained from neonatal mice. Cells were held at -80 mV and stimulated with 15-20 ms test depolarizations preceded and followed by voltage steps designed to isolate the slow calcium current. The slow calcium current had a threshold for activation of about 0 mV; the peak amplitude of the current reached a maximum at 30 to 40 mV a and then declined for still stronger depolarizations. The calcium transient had a threshold of about -10 mV, and its amplitude increased as a sigmoidal function of test potential and did not decrease again even for test depolarizations sufficiently strong (> or = 50 mV) that the amplitude of the slow calcium current became very small. Thus, the slow calcium current in myotubes appears to have a negligible role in the process of depolarization-induced release of intracellular calcium and this process in myotubes is essentially like that in adult skeletal muscle. After repolarization, however, the decay of the calcium transient in myotubes was very slow (hundreds of ms) compared to adult muscle, particularly after strong depolarizations that triggered larger calcium transients. Moreover, when cells were repolarized after strong depolarizations, the transient typically continued to increase slowly for up to several tens of ms before the onset of decay. This continued increase after repolarization was abolished by the addition of 5 mM BAPTA to the patch pipette although the rapid depolarization-induced release was not, suggesting that the slow increase might be a regenerative response triggered by the depolarization-induced release of calcium. The addition of

  4. Low-level luminescence as a method of detecting the UV influence on biological systems

    NASA Astrophysics Data System (ADS)

    Mei, Wei-Ping; Popp, Fritz A.

    1995-02-01

    It is well known that low-level luminescence is correlated to many physiological and biological parameters, e.g. cell cycle, temperature, oxidation- and UV-stress. We report some new approaches on low-level luminescence measurements and UV influence on different biological systems. One example concerns yeast cultures, which show an increasing intensity of luminescence after UV-treatment with a maximum after 1.5 h. Investigations on normal human fibroblasts and keratinocytes display different longtime kinetics: The former show no changes of the luminescence in time, the latter an increase that reaches the maximum after 9 h. The time-dependent spectral measurement on xeroderma pigmentosum after UV-treatment displays a time-shift of the action-spectra shifting the maximum from 400 nm to 420 nm in 12 h. Some results on neutrophils reveals spectral UV influence on respiratory burst and the cellular repair system. The results on human skin display spectral changes of low-level luminescence after UV-treatment. These results provide a useful tool of analyzing UV influence on human skin.

  5. Solidification of ash from incineration of low-level radioactive waste

    SciTech Connect

    Roberson, W A; Albenesius, E L; Becker, G W

    1983-01-01

    The safe disposal of both high-level and low-level radioactive waste is a problem of increasing national attention. A full-scale incineration and solidification process to dispose of suspect-level and low-level beta-gamma contaminated combustible waste is being demonstrated at the Savannah River Plant (SRP) and Savannah River Laboratory (SRL). The stabilized wasteform generated by the process will meet or exceed all future anticipated requirements for improved disposal of low-level waste. The incineration process has been evaluated at SRL using nonradioactive wastes, and is presently being started up in SRP to process suspect-level radioactive wastes. A cement solidification process for incineration products is currently being evaluated by SRL, and will be included with the incineration process in SRP during the winter of 1984. The GEM alumnus author conducted research in a related disposal solidification program during the GEM-sponsored summer internship, and upon completion of the Masters program, received full-time responsibility for developing the incineration products solidification process.

  6. Removal of Historic Low-Level Radioactive Sediment from the Port Hope Harbour - 13314

    SciTech Connect

    Kolberg, Mark; Case, Glenn; Ferguson Jones, Andrea

    2013-07-01

    At the Port Hope Harbour, located on the north shore of Lake Ontario, the presence of low-level radioactive sediment, resulting from a former radium and uranium refinery that operated alongside the Harbour, currently limits redevelopment and revitalization opportunities. These waste materials contain radium-226, uranium, arsenic and other contaminants. Several other on-land locations within the community of Port Hope are also affected by the low-level radioactive waste management practices of the past. The Port Hope Project is a community initiated undertaking that will result in the consolidation of an estimated 1.2 million cubic metres of the low-level radioactive waste from the various sites in Port Hope into a new engineered above ground long-term waste management facility. The remediation of the estimated 120,000 m{sup 3} of contaminated sediments from the Port Hope Harbour is one of the more challenging components of the Port Hope Project. Following a thorough review of various options, the proposed method of contaminated sediment removal is by dredging. The sediment from the dredge will then be pumped as a sediment-water slurry mixture into geo-synthetic containment tubes for dewatering. Due to the hard substrate below the contaminated sediment, the challenge has been to set performance standards in terms of low residual surface concentrations that are attainable in an operationally efficient manner. (authors)

  7. Disposal of low-level radioactive waste at the Savannah River Site

    SciTech Connect

    Sauls, V.W.

    1993-03-01

    An important objective of the Savannah River Site`s low-level radioactive waste management program is to isolate the waste from the environment both now and well into the future. A key element in achieving this is the disposal of low-level radioactive waste in sealed concrete vaults. Historically the Site has disposed of low-level radioactive waste via shallow land burial. In 1987, it was decided that better isolation from the environment was required. At that time several options for achieving this isolation were studied and below grade concrete vaults were chosen as the best method. This paper discusses the performance objectives for the vaults, the current design of the vaults and plans for the design of future vaults, the cost to construct the vaults, and the performance assessment on the vaults. Construction of the first set of vaults is essentially complete and readiness reviews before the start of waste receipt are being performed. Startup is to begin late in calendar year 1992 and continue through early CY 1993. The performance assessment is under way and the first draft is to be completed in early 1993.

  8. Identification of technical problems encountered in the shallow land burial of low-level radioactive wastes

    SciTech Connect

    Jacobs, D.G.; Epler, J.S.; Rose, R.R.

    1980-03-01

    A review of problems encountered in the shallow land burial of low-level radioactive wastes has been made in support of the technical aspects of the National Low-Level Waste (LLW) Management Research and Development Program being administered by the Low-Level Waste Management Program Office, Oak Ridge National Laboratory. The operating histories of burial sites at six major DOE and five commercial facilities in the US have been examined and several major problems identified. The problems experienced st the sites have been grouped into general categories dealing with site development, waste characterization, operation, and performance evaluation. Based on this grouping of the problem, a number of major technical issues have been identified which should be incorporated into program plans for further research and development. For each technical issue a discussion is presented relating the issue to a particular problem, identifying some recent or current related research, and suggesting further work necessary for resolving the issue. Major technical issues which have been identified include the need for improved water management, further understanding of the effect of chemical and physical parameters on radionuclide migration, more comprehensive waste records, improved programs for performance monitoring and evaluation, development of better predictive capabilities, evaluation of space utilization, and improved management control.

  9. The plasma torch for the vitrification of low-level radioactive waste

    SciTech Connect

    Peratt, A.L.

    1995-12-31

    Plasma torch technology provides a possible solution for radioactive material storage. During the past decade, plasma torches have been developed that produce temperatures as high as 25,000 F. Currently, the plasma torch finds application in solid waste vitrification and pyrolysis plants. Low-level radioactive waste is a topic of considerable interest for baseline technologies development, generally by means of low-temperature arc heating to characterize surrogate or low-level waste streams. High temperature plasma torches, the hottest members belonging to the family of plasma arc heaters, are efficient devices for reducing matter to its constituent elements but also the most complex in theory and operation. Characterization of the high energy density plasma instability that produces the intense heat, ranges from MHD computer modeling to stimulated Raman scattering by laser diagnostics. This paper describes the history of the plasma torch and the possible use of a 1-megawatt reverse polarity torch in a low-level radioactive waste testbed. Issues such as torch diagnostics, control, and the monitoring of radioactive gaseous, aqueous, solid, and plasma effluent streams are discussed.

  10. Measuring Agulhas Current strength and leakage from satellite altimetry

    NASA Astrophysics Data System (ADS)

    Le Bars, Dewi; De Ruijter, Wilhelmus P. M.; Dijkstra, Henk A.

    2013-04-01

    The Agulhas leakage is a flux of relatively warm and salty water from the Indian Ocean to the South Atlantic Ocean. It occurs south of the African continent where the Agulhas Current retroflects and sheds large anticyclonic eddies that quickly break up and mix with the surrounding water. This is one of the most energetic regions of the world ocean and the Agulhas leakage is therefore very difficult to quantify. In recent years two independent studies (Biastoch et al. 2009, Rouault et al. 2009) using different ocean models pointed out the possibility that the strength of the Agulhas leakage could have increased over the last decades. Unfortunately several discrepancies exist between these two studies on the magnitude and the causes of this increase showing the limitations of numerical modelling in this area. In this work we use a combination of along-track and mapped satellite geostrophic velocities to compute the strength of the Agulhas Current and to follow Lagrangian particles released in its core. The results confirm a positive trend of the volume of Agulhas leakage over the last two decades. This allows us to investigate the dependence of the leakage to upstream conditions like the Agulhas Current transport, the pattern and strength of the westerly winds and to test previous theories on the relations between these factors. Biastoch, A., Böning, C. W., Schwarzkopf, F. U. and Lutjeharms, J. R. E.: Increase in Agulhas leakage due to poleward shift of Southern Hemisphere westerlies, Nature, 462(7272), 495-498, doi:10.1038/nature08519, 2009. Rouault, M., Penven, P. and Pohl, B.: Warming in the Agulhas Current system since the 1980's, Geophys. Res. Lett, 36(L12602), doi:10.1029/2009GL037987, 2009.

  11. Occupational radiation exposures associated with alternative methods of low-level waste disposal

    SciTech Connect

    Herrington, W.N.; Harty, R.; Merwin, S.E.

    1987-05-01

    The Low-Level Radioactive Waste Policy Amendments (LLRWPA) Act of 1985 assigns the responsibility for disposal of low-level radioactive wastes to individual states. The Act also mandates that the US Nuclear Regulatory Commission (NRC), in consultation with states and other interested parties, identify disposal methods other than shallow land burial (SLB), the method currently used at the three low-level waste (LLW) disposal sites operating in the United States. The NRC contracted with Pacific Northwest Laboratory (PNL) to compare projected occupational exposures associated with the SLB method and five alternative disposal methods, including below ground vaults (BGV), above ground vaults (AGV), earth mounded concrete bunkers (EMCB), augured holes (AH) and minded cavities (MC). This report is intended to inform state and local governments about these projected exposures in anticipation of their participation in siting new low-level waste disposal facilities. The results of this study suggest that, with the design and operation assumptions made in this study, occupational dose equivalents for the five methods examined in detail would be highest for the EMCB method (1.81 person-mrem/m/sup 3/ of waste disposed). The lowest occupational dose equivalents would occur for the AH method (1.29 person-mrem/m/sup 3/). Projected occupational dose equivalents for SLB, BGV, and AGV disposal methods are 1.38, 1.47, and 1.61 person-mrem/m/sup 3/, respectively. Based on simularities between the reference BGV and MC facilities, it was projected that the occupational dose equivalents for a MC facility would be 40% higher than for the reference BGV facility. 17 refs., 15 figs., 13 tabs.

  12. Wall current probe: A non-invasive in situ plasma diagnostic for space and time resolved current density distribution measurement

    SciTech Connect

    Baude, R.; Gaboriau, F.; Hagelaar, G. J. M.

    2013-08-15

    In the context of low temperature plasma research, we propose a wall current probe to determine the local charged particle fluxes flowing to the chamber walls. This non-intrusive planar probe consists of an array of electrode elements which can be individually biased and for which the current can be measured separately. We detail the probe properties and present the ability of the diagnostic to be used as a space and time resolved measurement of the ion and electron current density at the chamber walls. This diagnostic will be relevant to study the electron transport in magnetized low-pressure plasmas.

  13. Wall current probe: a non-invasive in situ plasma diagnostic for space and time resolved current density distribution measurement.

    PubMed

    Baude, R; Gaboriau, F; Hagelaar, G J M

    2013-08-01

    In the context of low temperature plasma research, we propose a wall current probe to determine the local charged particle fluxes flowing to the chamber walls. This non-intrusive planar probe consists of an array of electrode elements which can be individually biased and for which the current can be measured separately. We detail the probe properties and present the ability of the diagnostic to be used as a space and time resolved measurement of the ion and electron current density at the chamber walls. This diagnostic will be relevant to study the electron transport in magnetized low-pressure plasmas.

  14. Alternatives generation and analysis report for immobilized low-level waste interim storage architecture

    SciTech Connect

    Burbank, D.A., Westinghouse Hanford

    1996-09-01

    The Immobilized Low-Level Waste Interim Storage subproject will provide storage capacity for immobilized low-level waste product sold to the U.S. Department of Energy by the privatization contractor. This report describes alternative Immobilized Low-Level Waste storage system architectures, evaluation criteria, and evaluation results to support the Immobilized Low-Level Waste storage system architecture selection decision process.

  15. Advances in low level uranium and plutonium isotope mass spectrometry using multiple ion counting and filament carburization

    NASA Astrophysics Data System (ADS)

    Richter, S.; Jakopic, R.; Kuehn, H.; Alonso, A.; Aregbe, Y.

    2008-12-01

    After upgrading IRMM's mass spectrometric capabilities for certification measurements for uranium and plutonium using large sample sizes during the previous years, in 2006-2007 we focused on necessary improvements in the area of low-level isotopic analyses for uranium and plutonium. This project was driven firstly by the need for reliable verification measurements for the Nuclear Signatures Measurement Evaluation Programme (NUSIMEP) samples at IRMM, secondly by the need for verification measurements on single uranium oxide reference particles and thirdly by the request from the IAEA's Safeguards Analytical Laboratory (SAL) to provide assistance for this type of analyses through the EC support programme. Improving low-level isotope mass spectrometry for uranium and plutonium at IRMM consisted of three steps. First a new thermal ionization mass spectrometer was acquired in order to have an instrument which can be used for peak-jumping measurements in ion counting mode, and which can be subsequently upgraded with a "Multiple Ion Counting" (MIC) system. This detector system allows the simultaneous detection of up to seven small ion beams with currents of 10-19 - 10-14 Ampere in ion counting mode, corresponding to count rates of 1-60.000 counts per second. As a result of test measurements with the MIC system it turned out that static measurements using the MIC system with a sample-versus-standard type external calibration can be associated with uncertainties even higher than in peak-jumping mode. The second step of improvement to tackle this situation was to implement the principle of "multi-dynamic" measurements for both uranium and plutonium measurements. This "multi- dynamic" measurement procedure provides an internal calibration of the MIC system and therefore circumvents the need for complicated inter-calibration routines. As a third step, a filament carburization procedure was implemented by which the ionization efficiencies for uranium and plutonium were improved

  16. Performance Assessment Monitoring Plan for the Hanford Site Low Level Waste Burial Grounds

    SciTech Connect

    SONNICHSEN, J.C.

    2000-11-15

    As directed by the U.S. Department of Energy (DOE), Richland Operations Office (DOE-RL), Fluor Hanford, Inc. will implement the requirements of DOE Order 435.1, Radioactive Waste Management, as the requirements relate to the continued operation of the low-level waste disposal facilities on the Hanford Site. DOE Order 435.1 requires a disposal authorization statement authorizing operation (or continued operation) of a low-level waste disposal facility. The objective of this Order is to ensure that all DOE radioactive waste is managed in a manner that protects the environment and personnel and public health and safety. The manual (DOE Order 435.1 Manual) implementing the Order states that a disposal authorization statement shall be issued based on a review of the facility's performance assessment and composite analysis or appropriate Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980 documentation. The disposal authorization shall specify the limits and conditions on construction, design, operations, and closure of the low-level waste facility. Failure to obtain a disposal authorization statement shall result in shutdown of an operational disposal facility. In fulfillment of the requirements of DOE Order 435.1, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area and the 200 West Area Low-Level Burial Grounds. The disposal authorization statement constitutes approval of the performance assessment and composite analysis, authorizes operation of the facility, and includes conditions that the disposal facility must meet. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area Low-Level Burial Grounds be written and approved by the DOE-RL. The monitoring plan is to be updated and implemented within 1 year following issuance of the disposal authorization statement to

  17. Comparison of buoy-mounted 74-kHz acoustic Doppler current profilers with vector-measuring current meters

    NASA Technical Reports Server (NTRS)

    Winant, Clinton; Mettlach, Theodore; Larson, Sigurd

    1994-01-01

    In December 1991, the National Data Buoy Center (NDBC) deployed two meteorological buoys in the Southern California Bight on a transect between San Diego and San Clemente Island. Each buoy consisted of a 10-m discus hull instrumented to measure a suite of meteorological parameters, and, for the first time in the NDBC buoy program, acoustic Doppler current profilers (ADCPs) were included to gather hourly current profiles beneath the two buoys. Moorings instrumented with seven vector-measuring current meters (VMCMs) were deployed adjacent to the NDBC buoys for several months and provided current observations for comparison with the ADCP measurements. When wave-induced buoy motion is not overly large, the observations of horizontal current made by the ADCP and the VMCM are highly correlated. Time series of differences between ADCP and VMCM measurements are characterized by a mean difference (bias error) of about 0.01 m/s and standard deviation of about 0.035 m/s for 1-h observations. Estimates of current spectra from ADCP and VMCM records suggest that the ADCP system can be characterized by a white noise level of 2 x 10(exp -3) sq m/sq s/cph. However, when the in situ environment is such that large surface waves are present (including breaking waves and whitecaps), erroneous current values are usually reported by the ADCP. Mean values of vertical velocities reported by the ADCP appear to be much larger than what could be physically expected and are therefore deemed unreliable.

  18. Cloud droplet size distributions in low-level stratiform clouds

    SciTech Connect

    Miles, N.L.; Verlinde, J.; Clothiaux, E.E.

    2000-01-15

    A database of stratus cloud droplet size distribution parameters, derived from in situ data reported in the existing literature, was created, facilitating intercomparison among datasets and quantifying typical values and their variability. From the datasets, which were divided into marine and continental groups, several parameters are presented, including the total number concentration, effective diameter, mean diameter, standard deviation of the droplet diameters about the mean diameter, and liquid water content, as well as the parameters of modified gamma and lognormal distributions. In light of these results, the appropriateness of common assumptions used in remote sensing of cloud droplet size distributions is discussed. For example, vertical profiles of mean diameter, effective diameter, and liquid water content agreed qualitatively with expectations based on the current paradigm of cloud formation. Whereas parcel theory predicts that the standard deviation about the mean diameter should decrease with height, the results illustrated that the standard deviation generally increases with height. A feature common to all marine clouds was their approximately constant total number concentration profiles; however, the total number concentration profiles of continental clouds were highly variable. Without cloud condensation nuclei spectra, classification of clouds into marine and continental groups is based on indirect methods. After reclassification of four sets of measurements in the database, there was a fairly clear dichotomy between marine and continental clouds, but a great deal of variability within each classification. The relevant applications of this study lie in radiative transfer and climate issues, rather than in cloud formation and dynamics. Techniques that invert remotely sensed measurements into cloud droplet size distributions frequently rely on a priori assumptions, such as constant number concentration profiles and constant spectral width. The

  19. Measuring the Burden—Current and Future Research Trends

    PubMed Central

    Breslow, Rosalind A.; Mukamal, Kenneth J.

    2014-01-01

    Alcohol has a significant impact on health and well-being, from the beneficial aspects of moderate drinking to the detrimental effects of alcoholism. The broad implications of alcohol use on public health have been addressed through a wide range of epidemiological and clinical studies, many of which are described in this issue of Alcohol Research: Current Reviews. Where chronic disease is involved, alcohol use can be a risk factor that not only affects the onset of various chronic diseases but also exacerbates the ongoing extent and severity of those diseases. Lifestyle choices and genetic influences also contribute to, or help to alleviate, that risk. PMID:24881334

  20. Greater-than-Class C low-level waste characterization. Appendix I: Impact of concentration averaging low-level radioactive waste volume projections

    SciTech Connect

    Tuite, P.; Tuite, K.; O`Kelley, M.; Ely, P.

    1991-08-01

    This study provides a quantitative framework for bounding unpackaged greater-than-Class C low-level radioactive waste types as a function of concentration averaging. The study defines the three concentration averaging scenarios that lead to base, high, and low volumetric projections; identifies those waste types that could be greater-than-Class C under the high volume, or worst case, concentration averaging scenario; and quantifies the impact of these scenarios on identified waste types relative to the base case scenario. The base volume scenario was assumed to reflect current requirements at the disposal sites as well as the regulatory views. The high volume scenario was assumed to reflect the most conservative criteria as incorporated in some compact host state requirements. The low volume scenario was assumed to reflect the 10 CFR Part 61 criteria as applicable to both shallow land burial facilities and to practices that could be employed to reduce the generation of Class C waste types.

  1. Role of Low-Level Laser Therapy in Neurorehabilitation

    PubMed Central

    Hashmi, Javad T.; Huang, Ying-Ying; Osmani, Bushra Z.; Sharma, Sulbha K.; Naeser, Margaret A.; Hamblin, Michael R.

    2011-01-01

    This year marks the 50th anniversary of the discovery of the laser. The development of lasers for medical use, which became known as low-level laser therapy (LLLT) or photobiomodulation, followed in 1967. In recent years, LLLT has become an increasingly mainstream modality, especially in the areas of physical medicine and rehabilitation. At first used mainly for wound healing and pain relief, the medical applications of LLLT have broadened to include diseases such as stroke, myocardial infarction, and degenerative or traumatic brain disorders. This review will cover the mechanisms of LLLT that operate both on a cellular and a tissue level. Mitochondria are thought to be the principal photoreceptors, and increased adenosine triphosphate, reactive oxygen species, intracellular calcium, and release of nitric oxide are the initial events. Activation of transcription factors then leads to expression of many protective, anti-apoptotic, anti-oxidant, and pro-proliferation gene products. Animal studies and human clinical trials of LLLT for indications with relevance to neurology, such as stroke, traumatic brain injury, degenerative brain disease, spinal cord injury, and peripheral nerve regeneration, will be covered. PMID:21172691

  2. Recent international developments in low-level waste disposal

    SciTech Connect

    Mitchell, S.J.; Lakey, L.T.; Harmon, K.M.

    1986-11-01

    Recent international developments in low-level waste (LLW) disposal have included a move away from ocean dumping and a trend towards engineered and deeper dispoosal. Siting efforts have accelerated as interim storage facilities and existing sites reach capacity. The suspension of ocean dumping by the London Dumping Conventions of 1983 and 1985 has affected the LLW disposal practices of several countries, including the United Kingdom, Belgium, the Netherlands, Switzerland, and Japan. Their plans now include disposal in trenches, shallow concrete pits, deep mines, sub-seabed caverns, horizontal mountain tunnels, and long-term storage facilities. Other recent developments include selection of the semi-desert Vaalputs site in South Africa, licensing activities for the Konrad mine site in the Federal Republic of Germany, design of at-reactor sites in Finland, and construction of a Baltic Sea site in Sweden. Also, the French have recently selected the Aube site for engineered disposal in monoliths and tumuli, now used at the La Manche site.

  3. Molten salt oxidation for treating low-level mixed wastes

    SciTech Connect

    Adamson, M G; Ford, T D; Foster, K G; Hipple, D L; Hopper, R W; Hsu, P C

    1998-12-10

    MS0 is a promising alternative to incineration for the treatment of a variety of organic wastes. Lawrence Livermore National Laboratory (LLNL) has prepared a facility (please see the photo attached) in which an integrated pilot-scale MS0 treatment system is being tested and demonstrated. The system consists of a MS0 vessel with a dedicated off-gas treatment system, a salt recycle system, feed preparation equipment, and a ceramic final waste forms immobilization system. The MSO/off-gas system has been operational since December 1997. The salt recycle system and the ceramic final forms immobilization became operational in May and August 1998, respectively. We have tested the MS0 facility with various organic feeds, including chlorinated solvents; tributyl phosphate/kerosene, PCB-contaminated waste oils & solvents, booties, plastic pellets, ion exchange resins, activated carbon, radioactive-spiked organics, and well-characterized low- level liquid mixed wastes. MS0 is a versatile technology for hazardous waste treatment and may be a solution to many waste disposal problems. In this paper we will present our operational experience with MS0 and also discuss its process capabilities as well as performance data with different feeds.

  4. Effect of Pulsing in Low-Level Light Therapy

    PubMed Central

    Hashmi, Javad T.; Huang, Ying-Ying; Sharma, Sulbha K.; Kurup, Divya Balachandran; De Taboada, Luis; Carroll, James D.; Hamblin, Michael R.

    2010-01-01

    Background and Objective Low level light (or laser) therapy (LLLT) is a rapidly growing modality used in physical therapy, chiropractic, sports medicine and increasingly in mainstream medicine. LLLT is used to increase wound healing and tissue regeneration, to relieve pain and inflammation, to prevent tissue death, to mitigate degeneration in many neurological indications. While some agreement has emerged on the best wavelengths of light and a range of acceptable dosages to be used (irradiance and fluence), there is no agreement on whether continuous wave or pulsed light is best and on what factors govern the pulse parameters to be chosen. Study Design/Materials and Methods The published peer-reviewed literature was reviewed between 1970 and 2010. Results The basic molecular and cellular mechanisms of LLLT are discussed. The type of pulsed light sources available and the parameters that govern their pulse structure are outlined. Studies that have compared continuous wave and pulsed light in both animals and patients are reviewed. Frequencies used in other pulsed modalities used in physical therapy and biomedicine are compared to those used in LLLT. Conclusion There is some evidence that pulsed light does have effects that are different from those of continuous wave light. However further work is needed to define these effects for different disease conditions and pulse structures. PMID:20662021

  5. Steam reforming of low-level mixed waste. Final report

    SciTech Connect

    1998-06-01

    ThermoChem has successfully designed, fabricated and operated a nominal 90 pound per hour Process Development Unit (PDU) on various low-level mixed waste surrogates. The design, construction, and testing of the PDU as well as performance and economic projections for a 300-lb/hr demonstration and commercial system are described. The overall system offers an environmentally safe, non-incinerating, cost-effective, and publicly acceptable method of processing LLMW. The steam-reforming technology was ranked the No. 1 non-incineration technology for destruction of hazardous organic wastes in a study commissioned by the Mixed Waste Focus Area and published in April 1997. The ThermoChem steam-reforming system has been developed over the last 13 years culminating in this successful test campaign on LLMW surrogates. Six surrogates were successfully tested including a 750-hour test on material simulating a PCB- and Uranium-contaminated solid waste found at the Portsmouth Gaseous Diffusion Plant. The test results indicated essentially total (> 99.9999%) destruction of RCRA and TSCA hazardous halogenated organics, significant levels of volume reduction (> 400 to 1), and retention of radionuclides in the volume-reduced solids. Economic evaluations have shown the steam-reforming system to be very cost competitive with more conventional and other emerging technologies.

  6. Technical issues in licensing low-level radioactive waste facilities

    SciTech Connect

    Junkert, R.

    1993-03-01

    The California Department of Health Service spent two years in the review of an application for a low-level radioactive waste disposal facility in California. During this review period a variety of technical issues had to be evaluated and resolved. One of the first issues was the applicability and use of NRC guidance documents for the development of LLW disposal facilities. Other technical issues that required intensive evaluations included surface water hydrology, seismic investigation, field and numerical analysis of the unsaturated zone, including a water infiltration test. Source term verification became an issue because of one specific isotope that comprised more than 90% of the curies projected for disposal during the operational period. The use of trench liners and the proposed monitoring of the unsaturated zone were reviewed by a highly select panel of experts to provide guidance on the need for liners and to ensure that the monitoring system was capable of monitoring sufficient representative areas for radionuclides in the soil, soil gas, and soil moisture. Finally, concerns about the quality of the preoperational environmental monitoring program, including data, sample collection procedures, laboratory analysis, data review and interpretation and duration of monitoring caused a significant delay in completing the licensing review.

  7. Low-level waste minimization at the Y-12 Plant

    SciTech Connect

    Koger, J.

    1993-03-01

    The Y-12 Development Waste Minimization Program is used as a basis for defining new technologies and processes that produce minimum low-level wastes (hazardous, mixed, radioactive, and industrial) for the Y-12 Plant in the future and for Complex-21 and that aid in decontamination and decommissioning (D and D) efforts throughout the complex. In the past, the strategy at the Y-12 Plant was to treat the residues from the production processes using chemical treatment, incineration, compaction, and other technologies, which often generated copious quantities of additional wastes and, with the exception of highly valuable materials such as enriched uranium, incorporated very little recycle in the process. Recycle, in this context, is defined as material that is put back into the process before it enters a waste stream. Additionally, there are several new technology drivers that have recently emerged with the changing climate in the Nuclear Weapons Complex such as Complex 21 and D and D technologies and an increasing number of disassemblies. The hierarchies of concern in the waste minimization effort are source reduction, recycle capability, treatment simplicity, and final disposal difficulty with regard to Complex 21, disassembly efforts, D and D, and, to a lesser extent, weapons production. Source reduction can be achieved through substitution of hazardous substances for nonhazardous materials, and process changes that result in less generated waste.

  8. Remediation alternatives for low-level herbicide contaminated groundwater

    SciTech Connect

    Conger, R.M.

    1995-10-01

    In early 1995, an evaluation of alternatives for remediation of a shallow groundwater plume containing low-levels of an organic herbicide was conducted at BASF Corporation, a petrochemical facility located in Ascension Parish, Louisiana. The contaminated site is located on an undeveloped portion of property within 1/4 mile of the east bank of the Mississippi River near the community of Geismar. Environmental assessment data indicated that about two acres of the thirty acre site had been contaminated from past waste management practices with the herbicide bentazon. Shallow soils and groundwater between 5 to 15 feet in depth were affected. Maximum concentrations of bentazon in groundwater were less than seven parts per million. To identify potentially feasible remediation alternatives, the environmental assessment data, available research, and cost effectiveness were reviewed. After consideration of a preliminary list of alternatives, only two potentially feasible alternatives could be identified. Groundwater pumping, the most commonly used remediation alternative, followed by carbon adsorption treatment was identified as was a new innovative alternative known as vegetative transpiration. This alternative relies on the natural transpiration processes of vegetation to bioremediate organic contaminants. Advantages identified during screening suggest that the transpiration method could be the best remediation alternative to address both economic and environmental factors. An experiment to test critical factors of the vegetatived transpiration alternative with bentazon was recommended before a final decision on feasibility can be made.

  9. Aerobic Denitrifying Bacteria That Produce Low Levels of Nitrous Oxide

    PubMed Central

    Takaya, Naoki; Catalan-Sakairi, Maria Antonina B.; Sakaguchi, Yasushi; Kato, Isao; Zhou, Zhemin; Shoun, Hirofumi

    2003-01-01

    Most denitrifiers produce nitrous oxide (N2O) instead of dinitrogen (N2) under aerobic conditions. We isolated and characterized novel aerobic denitrifiers that produce low levels of N2O under aerobic conditions. We monitored the denitrification activities of two of the isolates, strains TR2 and K50, in batch and continuous cultures. Both strains reduced nitrate (NO3−) to N2 at rates of 0.9 and 0.03 μmol min−1 unit of optical density at 540 nm−1 at dissolved oxygen (O2) (DO) concentrations of 39 and 38 μmol liter−1, respectively. At the same DO level, the typical denitrifier Pseudomonas stutzeri and the previously described aerobic denitrifier Paracoccus denitrificans did not produce N2 but evolved more than 10-fold more N2O than strains TR2 and K50 evolved. The isolates denitrified NO3− with concomitant consumption of O2. These results indicated that strains TR2 and K50 are aerobic denitrifiers. These two isolates were taxonomically placed in the β subclass of the class Proteobacteria and were identified as P. stutzeri TR2 and Pseudomonas sp. strain K50. These strains should be useful for future investigations of the mechanisms of denitrifying bacteria that regulate N2O emission, the single-stage process for nitrogen removal, and microbial N2O emission into the ecosystem. PMID:12788710

  10. Evaluation of Low-Level Laser Therapy in TMD Patients.

    PubMed

    Ayyildiz, Simel; Emir, Faruk; Sahin, Cem

    2015-01-01

    Light amplification by stimulated emission of radiation (laser) is one of the most recent treatment modalities in dentistry. Low-level laser therapy (LLLT) is suggested to have biostimulating and analgesic effects through direct irradiation without causing thermal response. There are few studies that have investigated the efficacy of laser therapy in temporomandibular disorders (TMD), especially in reduced mouth opening. The case report here evaluates performance of LLLT with a diode laser for temporomandibular clicking and postoperative findings were evaluated in two cases of TMD patients. First patient had a history of limited mouth opening and pain in temporomandibular joint (TMJ) region since nine months. Second patient's main complaint was his restricted mouth opening, which was progressed in one year. LLLT was performed with a 685 nm red probed diode laser that has an energy density of 6.2 J/cm(2), three times a week for one month, and application time was 30 seconds (685 nm, 25 mW, 30 s, 0.02 Hz, and 6.2 J/cm(2)) (BTL-2000, Portative Laser Therapy Device). The treatment protocol was decided according to the literature. One year later patients were evaluated and there were no changes. This application suggested that LLLT is an appropriate treatment for TMD related pain and limited mouth opening and should be considered as an alternative to other methods. PMID:26587294

  11. Low-level microwave irradiation and central cholinergic systems

    SciTech Connect

    Lai, H.; Carino, M.A.; Horita, A.; Guy, A.W. )

    1989-05-01

    Our previous research showed that 45 min of exposure to low-level, pulsed microwaves (2450-MHz, 2-microseconds pulses, 500 pps, whole-body average specific absorption rate 0.6 W/kg) decreased sodium-dependent high-affinity choline uptake in the frontal cortex and hippocampus of the rat. The effects of microwaves on central cholinergic systems were further investigated in this study. Increases in choline uptake activity in the frontal cortex, hippocampus, and hypothalamus were observed after 20 min of acute microwave exposure, and tolerance to the effect of microwaves developed in the hypothalamus, but not in the frontal cortex and hippocampus, of rats subjected to ten daily 20-min exposure sessions. Furthermore, the effects of acute microwave irradiation on central choline uptake could be blocked by pretreating the animals before exposure with the narcotic antagonist naltrexone. In another series of experiments, rats were exposed to microwaves in ten daily sessions of either 20 or 45 min, and muscarinic cholinergic receptors in different regions of the brain were studied by 3H-QNB binding assay. Decreases in concentration of receptors occurred in the frontal cortex and hippocampus of rats subjected to ten 20-min microwave exposure sessions, whereas increase in receptor concentration occurred in the hippocampus of animals exposed to ten 45-min sessions. This study also investigated the effects of microwave exposure on learning in the radial-arm maze. Rats were trained in the maze to obtain food reinforcements immediately after 20 or 45 min of microwave exposure.

  12. Oxidation Kinetics of Spent Low-Level Radioactive Resins

    SciTech Connect

    Huang, Y.-J.; Wang, H. Paul; Chao, Chih C.; Liu, H.H.; Hsiao, M.C.; Liu, S.H.

    2005-11-15

    Experimentally, two-stage oxidation of spent low-level radioactive resin was found by thermo- gravimetric analysis (TGA). About 24% of the spent resins was oxidized at 600 to 900 K. Online Fourier transform infrared spectra showed that the decomposition of the -SO{sub 3}H species in the resin to SO{sub 2} occurred at 670 and 1020 K. The numerical calculation from TGA weight loss data at different heating rates showed that the global activation energies for oxidation of the spent resins were 108 to 138 kJ.mol{sup -1}. The reaction orders for resin and oxygen were about 1.0 and 3.5, respectively. The global rate equations for oxidation of the resin in the first and second stages can be expressed as dx{sub 1}/dt (s{sup -1}) = 2.3 x 10{sup 7} (s{sup -1})exp[-117 900(J.mol{sup -1})/T(K)][1 - x (%)]{sup 0.82} [O{sub 2} (vt%)]{sup 3.5} (x denotes the reaction conversion) and dx{sub 2}/dt = 8.4 x 10{sup 17} exp(-239 500/RT) (1 - x){sup 0.9}[O{sub 2}]{sup 4.5}, respectively.

  13. WRAP low level waste (LLW) glovebox operational test report

    SciTech Connect

    Kersten, J.K.

    1998-02-19

    The Low Level Waste (LLW) Process Gloveboxes are designed to: receive a 55 gallon drum in an 85 gallon overpack in the Entry glovebox (GBIOI); and open and sort the waste from the 55 gallon drum, place the waste back into drum and relid in the Sorting glovebox (GB 102). In addition, waste which requires further examination is transferred to the LLW RWM Glovebox via the Drath and Schraeder Bagiess Transfer Port (DO-07-201) or sent to the Sample Transfer Port (STC); crush the drum in the Supercompactor glovebox (GB 104); place the resulting puck (along with other pucks) into another 85 gallon overpack in the Exit glovebox (GB 105). The status of the waste items is tracked by the Data Management System (DMS) via the Plant Control System (PCS) barcode interface. As an item is moved from the entry glovebox to the exit glovebox, the Operator will track an items location using a barcode reader and enter any required data on the DMS console. The Operational Test Procedure (OTP) will perform evolution`s (described below) using the Plant Operating Procedures (POP) in order to verify that they are sufficient and accurate for controlled glovebox operation.

  14. Towards Smart Homes Using Low Level Sensory Data

    PubMed Central

    Khattak, Asad Masood; Truc, Phan Tran Ho; Hung, Le Xuan; Vinh, La The; Dang, Viet-Hung; Guan, Donghai; Pervez, Zeeshan; Han, Manhyung; Lee, Sungyoung; Lee, Young-Koo

    2011-01-01

    Ubiquitous Life Care (u-Life care) is receiving attention because it provides high quality and low cost care services. To provide spontaneous and robust healthcare services, knowledge of a patient’s real-time daily life activities is required. Context information with real-time daily life activities can help to provide better services and to improve healthcare delivery. The performance and accuracy of existing life care systems is not reliable, even with a limited number of services. This paper presents a Human Activity Recognition Engine (HARE) that monitors human health as well as activities using heterogeneous sensor technology and processes these activities intelligently on a Cloud platform for providing improved care at low cost. We focus on activity recognition using video-based, wearable sensor-based, and location-based activity recognition engines and then use intelligent processing to analyze the context of the activities performed. The experimental results of all the components showed good accuracy against existing techniques. The system is deployed on Cloud for Alzheimer’s disease patients (as a case study) with four activity recognition engines to identify low level activity from the raw data captured by sensors. These are then manipulated using ontology to infer higher level activities and make decisions about a patient’s activity using patient profile information and customized rules. PMID:22247682

  15. Engineered sorbent barriers for improved low-level waste disposal

    SciTech Connect

    Mitchell, S.J.; Freeman, H.D.

    1987-01-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Lab., supported by the US Dept. of Energy's Low-Level Waste (LLW) Management Program, is developing sorbent materials to prevent the migration of radionuclides from LLW sites. Unlike impermeable barriers, sorbent barriers allow moisture to pass while selectively sorbing contaminants. This would prevent filling the waste site with water at humid sites, referred to as the bathtub effect. The sorptive behavior of these barriers is similar to the ion-exchange properties that many soils possess for certain radionuclides. However, the degree of sorption of radionuclides is dependent on the type of soil, the specific radionuclide, and the presence of competing ions and organic complexants. Therefore, the use of sorptive additives as radionuclide barriers is recommended to prevent radionuclide migration from the waste site. The experimental work discussed in this paper was directed toward identifying and evaluating sorbent materials for three radionuclides of major concern in defense LLW: /sup 137/Cs, /sup 60/Co, and /sup 90/Sr. No single material was found to be effective for sorbing all three radionuclides of interest. Therefore, formulations were developed containing A-51 zeolite or clinoptilolite for sorbing strontium, greensand or red pottery clay for sorbing cesium, and activated charcoal for sorbing cobalt.

  16. Engineered sorbent barriers for low-level waste disposal.

    SciTech Connect

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs.

  17. Credit WCT. Photographic copy of photograph, low level aerial view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit WCT. Photographic copy of photograph, low level aerial view of Test Stand "D," looking due south, after completion of Dd station installation in 1961. Note Test Stand "D" "neutralization pond" to immediate southeast of tower. A steel barrier north of and parallel to the Dd station separates fuel run tanks (on south side obscured from view) from oxidizer run tanks (on north side). Small Dj injector test stand is visible to the immediate left of oxidizer run tanks; it is oriented on a northeast/southwest diagonal to the Dd test station. The large tank to the north of the oxidizer run tanks (near center bottom of view) is an oxidizer storage tank for nitrogen tetroxide. Slender tanks to the northwest of the tower (lower right of view) contain high pressure nitrogen gas. A large vertical tank at the base of the tower contains distilled water for flushing propellant lines. (JPL negative no. 384-2997-B, 12 December 1961) - Jet Propulsion Laboratory Edwards Facility, Test Stand D, Edwards Air Force Base, Boron, Kern County, CA

  18. Honeybees as monitors of low levels of radioactivity

    SciTech Connect

    Simmons, M.A. ); Bromenshenk, J.J.; Gudatis, J.L. . Dept. of Zoology)

    1990-07-01

    Large-scale environmental monitoring programs rely on sampling many media -- air, water, food, et cetera -- from a large network of sampling stations. For describing the total region possibly impacted by contaminants, the most efficient sampler would be one that covered a large region and simultaneously sampled many different media, such as water, air, soil, and vegetation. Honeybees have been shown to be useful monitors of the environment in this context for detecting both radionuclides and heavy metals. This study sought to determine the effectiveness of honeybees as monitors of low levels of radioactivity in the form of tritium and gamma-emitting radionuclides. For the study, approximately 50 honeybee colonies were placed on the Hanford Site and along the Columbia River in areas downwind of the site. The mini-hive colonies were sampled after 1 month and tested for tritium and for gamma-emitting radionuclides. From this and other studies, it is known that honeybees can be used to detect radionuclides present in the environment. Their mobility and their ability to integrate all exposure pathways could expand and add another level of confidence to the present monitoring program. 6 refs., 1 fig., 2 tabs.

  19. Versatile Low Level RF System For Linear Accelerators

    SciTech Connect

    Potter, James M.

    2011-06-01

    The Low Level RF (LLRF) system is the source of all of the rf signals required for an rf linear accelerator. These signals are amplified to drive accelerator and buncher cavities. It can even provide the synchronizing signal for the rf power for a synchrotron. The use of Direct Digital Synthesis (DDS) techniques results in a versatile system that can provide multiple coherent signals at the same or different frequencies with adjustable amplitudes and phase relations. Pulsing the DDS allows rf switching with an essentially infinite on/off ratio. The LLRF system includes a versatile phase detector that allows phase-locking the rf frequency to a cavity at any phase angle over the full 360 deg. range. With the use of stepper motor driven slug tuners multiple cavity resonant frequencies can be phase locked to the rf source frequency. No external phase shifters are required and there is no feedback loop phase setup required. All that is needed is to turn the frequency feedback on. The use of Digital Signal Processing (DSP) allows amplitude and phase control over the entire rf pulse. This paper describes the basic principles of a LLRF system that has been used for both proton accelerators and electron accelerators, including multiple tank accelerators, sub-harmonic and fundamental bunchers, and synchrotrons.

  20. Selected radionuclides important to low-level radioactive waste management

    SciTech Connect

    1996-11-01

    The purpose of this document is to provide information to state representatives and developers of low level radioactive waste (LLW) management facilities about the radiological, chemical, and physical characteristics of selected radionuclides and their behavior in the environment. Extensive surveys of available literature provided information for this report. Certain radionuclides may contribute significantly to the dose estimated during a radiological performance assessment analysis of an LLW disposal facility. Among these are the radionuclides listed in Title 10 of the Code of Federal Regulations Part 61.55, Tables 1 and 2 (including alpha emitting transuranics with half-lives greater than 5 years). This report discusses these radionuclides and other radionuclides that may be significant during a radiological performance assessment analysis of an LLW disposal facility. This report not only includes essential information on each radionuclide, but also incorporates waste and disposal information on the radionuclide, and behavior of the radionuclide in the environment and in the human body. Radionuclides addressed in this document include technetium-99, carbon-14, iodine-129, tritium, cesium-137, strontium-90, nickel-59, plutonium-241, nickel-63, niobium-94, cobalt-60, curium -42, americium-241, uranium-238, and neptunium-237.

  1. Investigation of the low-level modulated light action

    NASA Astrophysics Data System (ADS)

    Antonov, Sergei N.; Sotnikov, V. N.; Koreneva, L. G.

    1994-07-01

    Now there exists no clear complete knowledge about mechanisms and pathways by which low level laser bioactivation works. Modulated laser light action has been investigated two new ways: dynamical infrared thermography and computing image of living brain. These ways permit observation in real time laser action on peripheral blood flow, reflex reactions to functional probes, thermoregulation mechanisms as well as brain electrical activity changes of humans. We have designed a universal apparatus which produced all regimes of the output laser light. It has a built-in He-Ne laser with an acousto-optic modulator and an infrared GaAs laser. The device provided spatial combination of both the light beams and permitted us to irradiate an object both separately and simultaneously. This research shows that the most effective frequencies range from several to dozens of hertz. The duty factor and frequency scanning are also important. On the basis of these results in Russian clinics new treatment methods using modulated light are applied in practical neurology, gynecology, etc.

  2. Versatile Low Level RF System For Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Potter, James M.

    2011-06-01

    The Low Level RF (LLRF) system is the source of all of the rf signals required for an rf linear accelerator. These signals are amplified to drive accelerator and buncher cavities. It can even provide the synchronizing signal for the rf power for a synchrotron. The use of Direct Digital Synthesis (DDS) techniques results in a versatile system that can provide multiple coherent signals at the same or different frequencies with adjustable amplitudes and phase relations. Pulsing the DDS allows rf switching with an essentially infinite on/off ratio. The LLRF system includes a versatile phase detector that allows phase-locking the rf frequency to a cavity at any phase angle over the full 360° range. With the use of stepper motor driven slug tuners multiple cavity resonant frequencies can be phase locked to the rf source frequency. No external phase shifters are required and there is no feedback loop phase setup required. All that is needed is to turn the frequency feedback on. The use of Digital Signal Processing (DSP) allows amplitude and phase control over the entire rf pulse. This paper describes the basic principles of a LLRF system that has been used for both proton accelerators and electron accelerators, including multiple tank accelerators, sub-harmonic and fundamental bunchers, and synchrotrons.

  3. Hanford low-level waste process chemistry testing data package

    SciTech Connect

    Smith, H.D.; Tracey, E.M.; Darab, J.G.; Smith, P.A.

    1996-03-01

    Recently, the Tri-Party Agreement (TPA) among the State of Washington Department of Ecology, U.S. Department of Energy (DOE) and the US Environmental Protection Agency (EPA) for the cleanup of the Hanford Site was renegotiated. The revised agreement specifies vitrification as the encapsulation technology for low level waste (LLW). A demonstration, testing, and evaluation program underway at Westinghouse Hanford Company to identify the best overall melter-system technology available for vitrification of Hanford Site LLW to meet the TPA milestones. Phase I is a {open_quotes}proof of principle{close_quotes} test to demonstrate that a melter system can process a simulated highly alkaline, high nitrate/nitrite content aqueous LLW feed into a glass product of consistent quality. Seven melter vendors were selected for the Phase I evaluation: joule-heated melters from GTS Duratek, Incorporated (GDI); Envitco, Incorporated (EVI); Penberthy Electomelt, Incorporated (PEI); and Vectra Technologies, Incorporated (VTI); a gas-fired cyclone burner from Babcock & Wilcox (BCW); a plasma torch-fired, cupola furnace from Westinghouse Science and Technology Center (WSTC); and an electric arc furnace with top-entering vertical carbon electrodes from the U.S. Bureau of Mines (USBM).

  4. Factors associated with low levels of aerobic fitness among adolescents

    PubMed Central

    Gonçalves, Eliane Cristina de Andrade; Silva, Diego Augusto Santos

    2016-01-01

    Abstract Objective: To evaluate the prevalence of low aerobic fitness levels and to analyze the association with sociodemographic factors, lifestyle and excess body fatness among adolescents of southern Brazil. Methods: The study included 879 adolescents aged 14-19 years the city of São José/SC, Brazil. The aerobic fitness was assessed by Canadian modified test of aerobic fitness. Sociodemographic variables (skin color, age, sex, study turn, economic level), sexual maturation and lifestyle (eating habits, screen time, physical activity, consumption of alcohol and tobacco) were assessed by a self-administered questionnaire. Excess body fatness was evaluated by sum of skinfolds triceps and subscapular. We used logistic regression to estimate odds ratios and 95% confidence intervals. Results: Prevalence of low aerobic fitness level was 87.5%. The girls who spent two hours or more in front screen, consumed less than one glass of milk by day, did not smoke and had an excess of body fatness had a higher chance of having lower levels of aerobic fitness. White boys with low physical activity had had a higher chance of having lower levels of aerobic fitness. Conclusions: Eight out of ten adolescents were with low fitness levels aerobic. Modifiable lifestyle factors were associated with low levels of aerobic fitness. Interventions that emphasize behavior change are needed. PMID:26743851

  5. Low-level laser therapy for Peyronie's disease

    NASA Astrophysics Data System (ADS)

    Johnson, Douglas E.; Bertini, John E. J.; Harris, James M.; Hawkins, Janet H.

    1995-05-01

    We are reporting the preliminary results of a nonrandomized trial using a low-level gallium- aluminum-arsenide (GaAlAs) laser at a wavelength of 830 nm (Microlight 830, Lasermedics, Inc., Stafford, TX) to treat patients with symptomatic Peyronie's disease. All patients entered into the study had disease consisting of a well-defined fibrous plaque causing pain and/or curvature of the penile shaft on erection that interfered with satisfactory sexual intercourse. Treatment has consisted of 30 mW administered over a duty cycle of 100 seconds (3 J) beginning at the base of the penis and extending to the coronal sulcus over the dorsum of the penis at 0.5 cm intervals. An additional duty cycle of 100 seconds was delivered to each 0.5 cm of palpable plaque. The ability of the therapy to reduce the size of the fibrous plaque, the severity of the penile curvature, and the severity of pain associated with penile erection and the treatment's effect on the patient's quality of life were assessed for each patient at completion of therapy and 6 weeks later.

  6. Low level laser therapy for traumatic brain injury

    NASA Astrophysics Data System (ADS)

    Wu, Qiuhe; Huang, Ying-Ying; Dhital, Saphala; Sharma, Sulbha K.; Chen, Aaron C.-H.; Whalen, Michael J.; Hamblin, Michael R.

    2010-02-01

    Low level laser (or light) therapy (LLLT) has been clinically applied for many indications in medicine that require the following processes: protection from cell and tissue death, stimulation of healing and repair of injuries, and reduction of pain, swelling and inflammation. One area that is attracting growing interest is the use of transcranial LLLT to treat stroke and traumatic brain injury (TBI). The fact that near-infrared light can penetrate into the brain would allow non-invasive treatment to be carried out with a low likelihood of treatment-related adverse events. LLLT may have beneficial effects in the acute treatment of brain damage injury by increasing respiration in the mitochondria, causing activation of transcription factors, reducing key inflammatory mediators, and inhibiting apoptosis. We tested LLLT in a mouse model of TBI produced by a controlled weight drop onto the skull. Mice received a single treatment with 660-nm, 810-nm or 980-nm laser (36 J/cm2) four hours post-injury and were followed up by neurological performance testing for 4 weeks. Mice with moderate to severe TBI treated with 660- nm and 810-nm laser had a significant improvement in neurological score over the course of the follow-up and histological examination of the brains at sacrifice revealed less lesion area compared to untreated controls. Further studies are underway.

  7. Evaluation of Low-Level Laser Therapy in TMD Patients

    PubMed Central

    Ayyildiz, Simel; Emir, Faruk; Sahin, Cem

    2015-01-01

    Light amplification by stimulated emission of radiation (laser) is one of the most recent treatment modalities in dentistry. Low-level laser therapy (LLLT) is suggested to have biostimulating and analgesic effects through direct irradiation without causing thermal response. There are few studies that have investigated the efficacy of laser therapy in temporomandibular disorders (TMD), especially in reduced mouth opening. The case report here evaluates performance of LLLT with a diode laser for temporomandibular clicking and postoperative findings were evaluated in two cases of TMD patients. First patient had a history of limited mouth opening and pain in temporomandibular joint (TMJ) region since nine months. Second patient's main complaint was his restricted mouth opening, which was progressed in one year. LLLT was performed with a 685 nm red probed diode laser that has an energy density of 6.2 J/cm2, three times a week for one month, and application time was 30 seconds (685 nm, 25 mW, 30 s, 0.02 Hz, and 6.2 J/cm2) (BTL-2000, Portative Laser Therapy Device). The treatment protocol was decided according to the literature. One year later patients were evaluated and there were no changes. This application suggested that LLLT is an appropriate treatment for TMD related pain and limited mouth opening and should be considered as an alternative to other methods. PMID:26587294

  8. Mixed low-level waste minimization at Los Alamos

    SciTech Connect

    Starke, T.P.

    1998-12-01

    During the first six months of University of California 98 Fiscal Year (July--December) Los Alamos National Laboratory has achieved a 57% reduction in mixed low-level waste generation. This has been accomplished through a systems approach that identified and minimized the largest MLLW streams. These included surface-contaminated lead, lead-lined gloveboxes, printed circuit boards, and activated fluorescent lamps. Specific waste minimization projects have been initiated to address these streams. In addition, several chemical processing equipment upgrades are being implemented. Use of contaminated lead is planned for several high energy proton beam stop applications and stainless steel encapsulated lead is being evaluated for other radiological control area applications. INEEL is assisting Los Alamos with a complete systems analysis of analytical chemistry derived mixed wastes at the CMR building and with a minimum life-cycle cost standard glovebox design. Funding for waste minimization upgrades has come from several sources: generator programs, waste management, the generator set-aside program, and Defense Programs funding to INEEL.

  9. Low-level laser therapy and invisible removal aligners.

    PubMed

    Caccianiga, G; Crestale, C; Cozzani, M; Piras, A; Mutinelli, S; Lo Giudice, A; Cordasco, G

    2016-01-01

    It seems that Low Level Laser Therapy (LLLT) stimulates orthodontic tooth movements, increasing the alveolar bone turnover. The aim of this study is to evaluate how LLLT can influence the orthodontic treatment with invisible removal aligner. A sample of 21 subjects was divided into two groups, a laser group (10 patients) and a control group (11 patients). All subjects were instructed to wear each aligner 12 hours a day for 2 weeks. Laser external bio-stimulation was given in the laser group every second week. The laser group successfully finished the treatment, while at 3rd – 5th aligner the control group did not finish the treatment. Laser treatment seemed to be better than treatment without laser. LLLT combined with aligners is able to favour, in 12 hours, the same tooth movement obtained by wearing the aligner 22 hours a day, according to the traditional protocol. This aspect could be useful for those patients who prefer not to use the aligners during the day. LLLT makes invisible removal aligner treatment more comfortable also because during the day the patients have to wear the aligners less hours than the treatment without laser. PMID:27469556

  10. Integrated software system for low level waste management

    SciTech Connect

    Worku, G.

    1995-12-31

    In the continually changing and uncertain world of low level waste management, many generators in the US are faced with the prospect of having to store their waste on site for the indefinite future. This consequently increases the set of tasks performed by the generators in the areas of packaging, characterizing, classifying, screening (if a set of acceptance criteria applies), and managing the inventory for the duration of onsite storage. When disposal sites become available, it is expected that the work will require re-evaluating the waste packages, including possible re-processing, re-packaging, or re-classifying in preparation for shipment for disposal under the regulatory requirements of the time. In this day and age, when there is wide use of computers and computer literacy is at high levels, an important waste management tool would be an integrated software system that aids waste management personnel in conducting these tasks quickly and accurately. It has become evident that such an integrated radwaste management software system offers great benefits to radwaste generators both in the US and other countries. This paper discusses one such approach to integrated radwaste management utilizing some globally accepted radiological assessment software applications.

  11. Depletion region surface effects in electron beam induced current measurements

    NASA Astrophysics Data System (ADS)

    Haney, Paul M.; Yoon, Heayoung P.; Gaury, Benoit; Zhitenev, Nikolai B.

    2016-09-01

    Electron beam induced current (EBIC) is a powerful characterization technique which offers the high spatial resolution needed to study polycrystalline solar cells. Current models of EBIC assume that excitations in the p-n junction depletion region result in perfect charge collection efficiency. However, we find that in CdTe and Si samples prepared by focused ion beam (FIB) milling, there is a reduced and nonuniform EBIC lineshape for excitations in the depletion region. Motivated by this, we present a model of the EBIC response for excitations in the depletion region which includes the effects of surface recombination from both charge-neutral and charged surfaces. For neutral surfaces, we present a simple analytical formula which describes the numerical data well, while the charged surface response depends qualitatively on the location of the surface Fermi level relative to the bulk Fermi level. We find that the experimental data on FIB-prepared Si solar cells are most consistent with a charged surface and discuss the implications for EBIC experiments on polycrystalline materials.

  12. Low-level lasers affect Escherichia coli cultures in hyperosmotic stress

    NASA Astrophysics Data System (ADS)

    Pinheiro, C. C.; Barboza, L. L.; Paoli, F.; Fonseca, A. S.

    2015-08-01

    Physical characteristics and practical properties have made lasers of interest for biomedical applications. Effects of low-level lasers on biological tissues could occur or be measurable depending on cell type, presence of a pathologic process or whether the cells are in an adverse environment. The objective of this work was to evaluate the survival, morphology and filamentation of E. coli cells proficient and deficient in the repair of oxidative DNA lesions exposed low-level red and infrared lasers submitted to hyperosmotic stress. Wild type and endonuclease VIII deficient E. coli cells in exponential and stationary growth phase were exposed to red and infrared lasers and submitted to hyperosmotic stress. Cell viability, filamentation phenotype and cell morphology were evaluated. Cell viability was not significantly altered but previous laser exposure induced filamentation and an altered area of stressed cells depending on physiologic condition and presence of the DNA repair. Results suggest that previous exposure to low-level red and infrared lasers could not affect viability but induced morphologic changes in cells submitted to hyperosmotic stress depending on physiologic conditions and repair of oxidative DNA lesions.

  13. Current noise measurements of surface defect states in amorphous silicon

    SciTech Connect

    West, P.W.; Kakalios, J.

    1999-07-01

    Measurements of conductance fluctuations in coplanar hydrogenated amorphous silicon (a-Si:H) are reported as a function of surface etching treatments. The noise power spectrum displays a broadened Lorentzian peak, associated with surface damage by CF{sub 4} reactive ion etching (RIE), whereas surface etches using ion milling or wet chemicals remove the Lorentzian spectral feature and only a 1/f spectral form for frequency f is observed. The Lorentzian spectral feature can be explained by trapping-detrapping from surface states induced by the RIE etch, which cause fluctuations in the depletion width of the space charge region near the film surface. The thermally activated Lorentzian corner frequency is a measure of the degree of band bending and the Fermi energy at the thin film surface.

  14. Bio-optical Measurement in the California Current

    NASA Technical Reports Server (NTRS)

    Mitchell, B. Greg

    2005-01-01

    We measured the optical and bio-geochemical properties during the autumn 2004 CalCOFI cruise. Calibration of in situ radiometry instruments We maintain NIST-traceable calibration of our PRR-800/8 10 radiometers. SIRREX-linked calibrations for our PRR-800/8 10 have been accomplished by Biospherical Instruments, Inc. (BSI) and SDSU Center for Hydro Optics and Remote Sensing (CHORS) since May 1993.

  15. Current methods for the measurement of growth hormone in urine.

    PubMed

    Hourd, P; Edwards, R

    1994-02-01

    Since the development of sensitive immunoassay procedures for the measurement of GH in urine, a urinary GH determination has been proposed as an alternative way of assessing pituitary GH secretion. Whilst studies on the clinical application of these assays have been difficult to correlate, for the reasons described, it is clear that an estimation of urinary GH has a useful role in clinical and physiological studies in both children and adults. PMID:8137512

  16. The current research of planetary nebulae distance measurement

    NASA Astrophysics Data System (ADS)

    Yang, Yuan-yuan; Zhu, Hui; Tian, Wen-wu; Wu, Dan

    2015-08-01

    Planetary Nebula is an important tracer of Galactic chemical history and evolution, star and interstellar evolution. Distance as a basic physical parameter of planetary nebula, is crucial to study its size, luminosity, ionized mass, formation rate, space density and Galactic distribution. Distance of planetary nebula has been studied for several decades, but most of their distances are not well determined, e.g. only thirty-one planetary nebulae have distance measurement with uncertainty within 20%. We summarize major distance measurement methods of planetary nebulae, i.e., trigonometric parallax, cluster member, expansion parallax, spectroscopic parallax, reddening, Na D absorption, determinations of central star gravities, Shklovsky method, kinematics method, and then discuss the limitations and applications scope of each method in detail. Actually, applying different methods to the same planetary nebulae can have a huge difference in distance, and even the same method can lead to great difference for the same planetary nebula. We focus on the kinematics method applied to planetary nebulae either seriously effected by Galactic extinction or having no observable centra star but being radio bright. The kinematics distance has been used in our on-going project of radio planetary nebulae distance measurement.

  17. Highly sensitive vacuum ion pump current measurement system

    DOEpatents

    Hansknecht, John Christopher

    2006-02-21

    A vacuum system comprising: 1) an ion pump; 2) power supply; 3) a high voltage DC--DC converter drawing power from the power supply and powering the vacuum pump; 4) a feedback network comprising an ammeter circuit including an operational amplifier and a series of relay controlled scaling resistors of different resistance for detecting circuit feedback; 5) an optional power block section intermediate the power supply and the high voltage DC--DC converter; and 6) a microprocessor receiving feedback information from the feedback network, controlling which of the scaling resistors should be in the circuit and manipulating data from the feedback network to provide accurate vacuum measurement to an operator.

  18. Performance Assessment Monitoring Plan for the Hanford Site Low-Level Burial Grounds

    SciTech Connect

    2006-03-30

    The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy reactor-compartment trench only. Hence, as of July 2004, only the two lined trenches in burial ground 218-W-5 (trenches 31 and 34, see Appendix A) and the Navy reactor-compartment trench in burial ground 218 E 12B (trench 94) are allowed to receive waste. When the two lined trenches are filled, the LLBG will cease to operate except for reactor compartment disposal at trench 94. Remaining operational lifetime of the LLBG is dependent on waste volume disposal rates. Existing programs for air sampling and analyses and subsidence monitoring are currently adequate for performance assessment at the LLBG. The waste disposal authorization for the Hanford Site is based (in part) on the post-closure performance assessments for the LLBG. In order to maintain a useful link between operational monitoring (e.g., Resource Conservation and Recovery Act [RCRA], Comprehensive Environmental Response, Compensation, and Liability Act, and State Waste Discharge Permits), constituents, monitoring frequencies, and boundaries require

  19. Microbial contamination detection at low levels by [125]I radiolabeling

    NASA Astrophysics Data System (ADS)

    Summers, David; Karouia, Fathi

    Contamination of mission spacecraft is an ongoing issue. A broad diversity of microorganisms have been detected in clean rooms where spacecraft are assembled. Some of which, depicted as oligotroph, are of special regard, as they are capable of colonizing inorganic surfaces like metal, and have been shown to be a concern for forward contamination of pristine celestial bodies. Currently, the NASA standard assay is the only approved assay intended for the enumeration of spores and heterotrophic microbial populations. However, culture-based microbial detection methods underestimate the viable microbial population. More recently, adenosine triphosphate (ATP) bioluminescence and limulus amebocyte lysate (LAL) assays, which employ measure-ments of selected metabolic products as a proxy of biomass, have been used successfully to circumvent the necessity of the growth of microorganisms in order to estimate the biodurdens associated with spacecraft assembly facility. However, these methods have limitation in the amount of cells that can be detected, i.e., 103 cells, and the type of microorganisms respec-tively. This work seeks to develop a new highly sensitive method for the determination of bioburdens (and the detection of microorganisms and life) that is independant of the type of organism while preserving a good turn-around time for analysis for planetary protection purposes. The assay is based on the detection of the organism's protein by labeling them by radioiodination, 125 I, of aromatic rings on tyrosine amino acids residues. Radiolabeling techniques are inherently sensitive and 125 I, in particular, benefits from a 60 day half-life, providing greater activity and signal per unit number of labels. Furthermore, microorganisms can contain over 50% of protein by dry weight. Thus, just one label per protein increases the sensitivity, compared to the ATP and LAL assays, by one and three orders of magnitude by using standard detection methods and the use of multiphoton

  20. Measuring bi-directional current through a field-effect transistor by virtue of drain-to-source voltage measurement

    DOEpatents

    Turner, Steven Richard

    2006-12-26

    A method and apparatus for measuring current, and particularly bi-directional current, in a field-effect transistor (FET) using drain-to-source voltage measurements. The drain-to-source voltage of the FET is measured and amplified. This signal is then compensated for variations in the temperature of the FET, which affects the impedance of the FET when it is switched on. The output is a signal representative of the direction of the flow of current through the field-effect transistor and the level of the current through the field-effect transistor. Preferably, the measurement only occurs when the FET is switched on.

  1. Determination of low levels of amorphous content in inhalation grade lactose by moisture sorption isotherms.

    PubMed

    Vollenbroek, Jasper; Hebbink, Gerald A; Ziffels, Susanne; Steckel, Hartwig

    2010-08-16

    Alpha-lactose monohydrate is widely used as an excipient in dry powder inhalers, and plays a very important role in the efficiency of the drug delivery. Due to the processing, low levels of amorphous lactose could be present in the blends. Varying amounts could have a strong effect on the efficiency of drug delivery of the powder blends. Therefore, the accurate measurement of low levels of amorphous lactose content is very important. A new method was developed to measure the amorphous content, based on dynamic vapour sorption (DVS). In contrast to the traditional re-crystallization approach of amorphous lactose, the new method is based on moisture sorption isotherms. Moisture sorption isotherms of blends of crystalline alpha-lactose and freeze-dried or spray-dried amorphous lactose were measured. By fitting the data with a Brunauer, Emmett, and Teller (BET) isotherm, a linear correlation was found between measured and actual amorphous content for the whole range of 0.1-100%. Differences between freeze-dried and spray-dried lactose, due to different molecular arrangements, could be removed by a preconditioning the samples at 35% RH prior to the isotherm measurement. It was shown that accurate determination of very low concentrations of amorphous lactose content is possible using moisture sorption isotherm analyses. PMID:20493937

  2. THE ELECTRICAL CAPACITY OF VALONIA : DIRECT CURRENT MEASUREMENTS.

    PubMed

    Blinks, L R; Skow, R K

    1940-11-20

    Impaled cells of Valonia were balanced in a Wheatstone bridge against a simple series-parallel circuit of two resistances and a capacity, the transient charge and discharge curves at make and break of direct current being recorded with a string galvanometer. With the resistances properly balanced, a series of characteristic deflections resulted when the balancing capacity was varied. With many cells, no complete capacity balance was ever attained over the entire transient time course; but instead either a monophasic or diphasic residual deflection always remained. This behavior is comparable to that of a polarizing electrode in D.C., although not so clearly marked; and it is concluded that Valonia usually has an appreciable polarization component, probably in parallel with a static capacity. However, some cells can be balanced almost completely against a mica condenser of proper value, which indicates that they display a nearly pure static capacity under some conditions. This static state could be produced experimentally by exposure to weak acids (acetic, carbonic, etc.) and by metabolic agents probably inducing internal acidity (low oxygen tension, long exposure to cold, narcotics, etc.). Conversely, penetrating weak bases, such as ammonia, abolished the static capacity, or even any regular polarization. Light acts something like ammonia, after an initial "acid gush" anomaly. Most of these agents likewise affect the P.D. and its response to external ionic alterations, and it seems likely that the change in capacity type reflects altered ionic permeabilities and relative mobilities. PMID:19873211

  3. Effects of Low-Level Blast Exposure on the Nervous System: Is There Really a Controversy?

    PubMed Central

    Elder, Gregory A.; Stone, James R.; Ahlers, Stephen T.

    2014-01-01

    High-pressure blast waves can cause extensive CNS injury in human beings. However, in combat settings, such as Iraq and Afghanistan, lower level exposures associated with mild traumatic brain injury (mTBI) or subclinical exposure have been much more common. Yet controversy exists concerning what traits can be attributed to low-level blast, in large part due to the difficulty of distinguishing blast-related mTBI from post-traumatic stress disorder (PTSD). We describe how TBI is defined in human beings and the problems posed in using current definitions to recognize blast-related mTBI. We next consider the problem of applying definitions of human mTBI to animal models, in particular that TBI severity in human beings is defined in relation to alteration of consciousness at the time of injury, which typically cannot be assessed in animals. However, based on outcome assessments, a condition of “low-level” blast exposure can be defined in animals that likely approximates human mTBI or subclinical exposure. We review blast injury modeling in animals noting that inconsistencies in experimental approach have contributed to uncertainty over the effects of low-level blast. Yet, animal studies show that low-level blast pressure waves are transmitted to the brain. In brain, low-level blast exposures cause behavioral, biochemical, pathological, and physiological effects on the nervous system including the induction of PTSD-related behavioral traits in the absence of a psychological stressor. We review the relationship of blast exposure to chronic neurodegenerative diseases noting the paradoxical lowering of Abeta by blast, which along with other observations suggest that blast-related TBI is pathophysiologically distinct from non-blast TBI. Human neuroimaging studies show that blast-related mTBI is associated with a variety of chronic effects that are unlikely to be explained by co-morbid PTSD. We conclude that abundant evidence supports low-level blast as having long

  4. Low Level Waste Conceptual Design Adaption to Poor Geological Conditions

    SciTech Connect

    Bell, J.; Drimmer, D.; Giovannini, A.; Manfroy, P.; Maquet, F.; Schittekat, J.; Van Cotthem, A.; Van Echelpoel, E.

    2002-02-26

    Since the early eighties, several studies have been carried out in Belgium with respect to a repository for the final disposal of low-level radioactive waste (LLW). In 1998, the Belgian Government decided to restrict future investigations to the four existing nuclear sites in Belgium or sites that might show interest. So far, only two existing nuclear sites have been thoroughly investigated from a geological and hydrogeological point of view. These sites are located in the North-East (Mol-Dessel) and in the mid part (Fleurus-Farciennes) of the country. Both sites have the disadvantage of presenting poor geological and hydrogeological conditions, which are rather unfavorable to accommodate a surface disposal facility for LLW. The underground of the Mol-Dessel site consists of neogene sand layers of about 180 m thick which cover a 100 meters thick clay layer. These neogene sands contain, at 20 m depth, a thin clayey layer. The groundwater level is quite close to the surface (0-2m) and finally, the topography is almost totally flat. The upper layer of the Fleurus-Farciennes site consists of 10 m silt with poor geomechanical characteristics, overlying sands (only a few meters thick) and Westphalian shales between 15 and 20 m depth. The Westphalian shales are tectonized and strongly weathered. In the past, coal seams were mined out. This activity induced locally important surface subsidence. For both nuclear sites that were investigated, a conceptual design was made that could allow any unfavorable geological or hydrogeological conditions of the site to be overcome. In Fleurus-Farciennes, for instance, the proposed conceptual design of the repository is quite original. It is composed of a shallow, buried concrete cylinder, surrounded by an accessible concrete ring, which allows permanent inspection and control during the whole lifetime of the repository. Stability and drainage systems should be independent of potential differential settlements an d subsidences

  5. Wound healing stimulation in mice by low-level light

    NASA Astrophysics Data System (ADS)

    Demidova, Tatiana N.; Herman, Ira M.; Salomatina, Elena V.; Yaroslavsky, Anna N.; Hamblin, Michael R.

    2006-02-01

    It has been known for many years that low levels of laser or non-coherent light (LLLT) accelerate some phases of wound healing. LLLT can stimulate fibroblast and keratinocyte proliferation and migration. It is thought to work via light absorption by mitochondrial chromophores leading to an increase in ATP, reactive oxygen species and consequent gene transcription. However, despite many reports about the positive effects of LLLT on wound healing, its use remains controversial. Our laboratory has developed a model of a full thickness excisional wound in mice that allows quantitative and reproducible light dose healing response curves to be generated. We have found a biphasic dose response curve with a maximum positive effect at 2 J/cm2 of 635-nm light and successively lower beneficial effects from 3-25 J/cm2, the effect is diminished at doses below 2J/cm2 and gradually reaches control healing levels. At light doses above 25 J/cm2 healing is actually worse than controls. The two most effective wavelengths of light were found to be 635 and 820-nm. We found no difference between filtered 635+/-15-nm light from a lamp and 633-nm light from a HeNe laser. The strain and age of the mouse affected the magnitude of the effect. Light treated wounds start to contract after illumination while control wounds initially expand for the first 24 hours. Our hypothesis is that a single brief light exposure soon after wounding affects fibroblast cells in the margins of the wound. Cells may be induced to proliferate, migrate and assume a myofibroblast phenotype. Our future work will be focused on understanding the mechanisms underlying effects of light on wound healing processes.

  6. Asthma and low level air pollution in Helsinki

    SciTech Connect

    Poenkae A5 )

    1991-09-01

    The effects of relatively low levels of air pollution and weather conditions on the number of patients who had asthma attacks and who were admitted to a hospital were studied in Helsinki during a 3-y period. The number of admissions increased during cold weather (n = 4,209), especially among persons who were of working age but not among children. Even after standardization for temperature, all admissions, including emergency ward admissions, were significantly correlated with ambient air concentrations of nitrogen dioxide (NO2), nitric oxide (NO), sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), and total suspended particulates (TSP). Regression analysis revealed that NO and O3 were most strongly associated with asthma problems. Effects of air pollutants and cold were maximal if they occurred on the same day, except for O3, which had a more pronounced effect after a 1-d lag. The associations between pollutants, low temperature, and admissions were most significant among adults of working age, followed by the elderly. Among children, only O3 and NO were significantly correlated with admissions. Levels of pollutants were fairly low, the long-term mean being 19.2 micrograms/m3 for SO2, 38.6 micrograms/m3 for NO2, 22.0 micrograms/m3 or O3, and 1.3 mg/m3 for CO. In contrast, the mean concentration of TSP was high (76.3 micrograms/m3), and the mean temperature was low (+ 4.7 degrees C). These results suggest that concentrations of pollutants lower than those given as guidelines in many countries may increase the incidence of asthma attacks.

  7. Microbial degradation of low-level radioactive waste. Final report

    SciTech Connect

    Rogers, R.D.; Hamilton, M.A.; Veeh, R.H.; McConnell, J.W. Jr

    1996-06-01

    The Nuclear Regulatory Commission stipulates in 10 CFR 61 that disposed low-level radioactive waste (LLW) be stabilized. To provide guidance to disposal vendors and nuclear station waste generators for implementing those requirements, the NRC developed the Technical Position on Waste Form, Revision 1. That document details a specified set of recommended testing procedures and criteria, including several tests for determining the biodegradation properties of waste forms. Information has been presented by a number of researchers, which indicated that those tests may be inappropriate for examining microbial degradation of cement-solidified LLW. Cement has been widely used to solidify LLW; however, the resulting waste forms are sometimes susceptible to failure due to the actions of waste constituents, stress, and environment. The purpose of this research program was to develop modified microbial degradation test procedures that would be more appropriate than the existing procedures for evaluation of the effects of microbiologically influenced chemical attack on cement-solidified LLW. The procedures that have been developed in this work are presented and discussed. Groups of microorganisms indigenous to LLW disposal sites were employed that can metabolically convert organic and inorganic substrates into organic and mineral acids. Such acids aggressively react with cement and can ultimately lead to structural failure. Results on the application of mechanisms inherent in microbially influenced degradation of cement-based material are the focus of this final report. Data-validated evidence of the potential for microbially influenced deterioration of cement-solidified LLW and subsequent release of radionuclides developed during this study are presented.

  8. In vitro transdentinal effect of low-level laser therapy

    NASA Astrophysics Data System (ADS)

    Oliveira, C. F.; Basso, F. G.; dos Reis, R. I.; Parreiras-e-Silva, L. T.; Lins, E. C.; Kurachi, C.; Hebling, J.; Bagnato, V. S.; de Souza Costa, C. A.

    2013-05-01

    Low-level laser therapy (LLLT) has been used for the treatment of dentinal hypersensitivity. However, the specific LLL dose and the response mechanisms of these cells to transdentinal irradiation have not yet been demonstrated. Therefore, this study evaluated the transdentinal effects of different LLL doses on stressed odontoblast-like pulp cells MDPC-23 seeded onto the pulpal side of dentin discs obtained from human third molars. The discs were placed in devices simulating in vitro pulp chambers and the whole set was placed in 24-well plates containing plain culture medium (DMEM). After 24 h incubation, the culture medium was replaced by fresh DMEM supplemented with either 5% (simulating a nutritional stress condition) or 10% fetal bovine serum (FBS). The cells were irradiated with doses of 15 and 25 J cm-2 every 24 h, totaling three applications over three consecutive days. The cells in the control groups were removed from the incubator for the same times as used in their respective experimental groups for irradiation, though without activating the laser source (sham irradiation). After 72 h of the last active or sham irradiation, the cells were evaluated with respect to succinic dehydrogenase (SDH) enzyme production (MTT assay), total protein (TP) expression, alkaline phosphatase (ALP) synthesis, reverse transcriptase polymerase chain reaction (RT-PCR) for collagen type 1 (Col-I) and ALP, and morphology (SEM). For both tests, significantly higher values were obtained for the 25 J cm-2 dose. Regarding SDH production, supplementation of the culture medium with 5% FBS provided better results. For TP and ALP expression, the 25 J cm-2 presented higher values, especially for the 5% FBS concentration (Mann-Whitney p < 0.05). Under the tested conditions, near infrared laser irradiation at 25 J cm-2 caused transdentinal biostimulation of odontoblast-like MDPC-23 cells.

  9. The effect of low level laser on anaplastic thyroid cancer

    NASA Astrophysics Data System (ADS)

    Rhee, Yun-Hee; Moon, Jeon-Hwan; Ahn, Jin-Chul; Chung, Phil-Sang

    2015-02-01

    Low-level laser therapy (LLLT) is a non-thermal phototherapy used in several medical applications, including wound healing, reduction of pain and amelioration of oral mucositis. Nevertheless, the effects of LLLT upon cancer or dysplastic cells have been so far poorly studied. Here we report that the effects of laser irradiation on anaplastic thyroid cancer cells leads to hyperplasia. 650nm of laser diode was performed with a different time interval (0, 15, 30, 60J/cm2 , 25mW) on anaplastic thyroid cancer cell line FRO in vivo. FRO was orthotopically injected into the thyroid gland of nude mice and the irradiation was performed with the same method described previously. After irradiation, the xenograft evaluation was followed for one month. The thyroid tissues from sacrificed mice were undergone to H&E staining and immunohistochemical staining with HIF-1α, Akt, TGF-β1. We found the aggressive proliferation of FRO on thyroid gland with dose dependent. In case of 60 J/ cm2 of energy density, the necrotic bodies were found in a center of the thyroid. The phosphorylation of HIF-1α and Akt was detected in the thyroid gland, which explained the survival signaling of anaplastic cancer cell was turned on the thyroid gland. Furthermore, TGF-β1 expression was decreased after irradiation. In this study, we demonstrated that insufficient energy density irradiation occurred the decreasing of TGF-β1 which corresponding to the phosphorylation of Akt/ HIF-1α. This aggressive proliferation resulted to the hypoxic condition of tissue for angiogenesis. We suggest that LLLT may influence to cancer aggressiveness associated with a decrease in TGF-β1 and increase in Akt/HIF-1α.

  10. The impact of NRC guidance on concentration averaging on low level waste sealed source disposal - 11424

    SciTech Connect

    Whitworth, Julia; Stewart, Bill; Cuthbertson, Abigail

    2011-01-20

    As part of its ongoing efforts to revise the Nuclear Regulatory Commission's (NRC) current position on blending to be risk-informed and performance based and its current review of the low-level waste classification codified in 10 CFR 61.55, the Nuclear Regulatory Commission (NRC) has stated that it may review the 1995 'Branch Technical Position on Concentration Averaging and Encapsulation' (BTP), which is still commonly used today. Such a review will have timely advantages, given the lack of commercial disposal availability within the United States for radioactive sealed sources that are in wide beneficial use across the country. The current application of the BTP guidance has resulted in an effective cap on commercial disposal for sources larger than 1.1 TBq (30 Ci). This paper will analyze how the BTP has been implemented with respect to sealed sources, what the implications have been for commercial disposal availability, and whether alternative packaging configurations could be considered for disposal.

  11. Magnetopause Current Measurements Using the Magnetospheric Multiscale Mission: A Dynamic Current-Strength in Regions of Opposing Magnetic Forces

    NASA Astrophysics Data System (ADS)

    Russell, Christopher T.; Strangeway, Robert J.; Zhao, Cong; Anderson, Brian J.; Baumjohann, Wolfgang; Bromund, Kenneth R.; Fischer, David; Kepko, Larry; Le, Guan; Leinweber, Hannes K.; Magnes, Werner; Nakamura, Rumi; Torbert, Roy B.; Burch, James L.

    2016-04-01

    The fluxgate magnetometers on the MMS mission with the aid of the electron drift instruments have been turned into an extremely precise curlometer, probing the currents in volumes down to about 10 km across. These measurements have revealed that the magnetopause is a dynamic boundary in more than just its location, but also in its thickness, current strength and force balance. We examine sample magnetopause crossings and illustrate this unexpected behavior of the boundary.

  12. High frequency radar measurements of tidal currents flowing through San Pablo Strait, San Francisco Bay

    USGS Publications Warehouse

    Maresca, Joseph W., Jr.; Padden, Robin R.; Cheng, Ralph T.; Seibel, Erwin

    1980-01-01

    High frequency (HF) radar measurements of the surface current averaged over the upper 0.5 m in San Pablo Strait were compared with current meter measurements of the subsurface current made at 9.4 m below mean lower low water (MLLW) over two 12.4-h tidal cycles. After averaging the radar and current meter data over two tidal cycles, a southerly (ebbing direction) surface current of 32 cm·s−1 was deduced from the radar measurements and a northerly (flooding direction) subsurface current of 7 cm·s−1 from the current meter measurements. This nontidal flow is maintained by freshwater discharge from the Sacramento–San Joaquin Rivers into Suisun and San Pablo Bays. The radar measurement technique provides quantitative estimates of the surface currents that previously were determined only from surface drifter studies.

  13. Field-aligned electric currents and their measurement by the incoherent backscatter technique

    NASA Technical Reports Server (NTRS)

    Bauer, P.; Cole, K. D.; Lejeume, G.

    1975-01-01

    Field aligned electric currents flow in the magnetosphere in many situations of fundamental geophysical interest. It is shown here that the incoherent backscatter technique can be used to measure these currents when the plasma line can be observed. The technique provides a ground based means of measuring these currents which complements the rocket and satellite ones.

  14. International low level waste disposal practices and facilities

    SciTech Connect

    Nutt, W.M.

    2011-12-19

    The safe management of nuclear waste arising from nuclear activities is an issue of great importance for the protection of human health and the environment now and in the future. The primary goal of this report is to identify the current situation and practices being utilized across the globe to manage and store low and intermediate level radioactive waste. The countries included in this report were selected based on their nuclear power capabilities and involvement in the nuclear fuel cycle. This report highlights the nuclear waste management laws and regulations, current disposal practices, and future plans for facilities of the selected international nuclear countries. For each country presented, background information and the history of nuclear facilities are also summarized to frame the country's nuclear activities and set stage for the management practices employed. The production of nuclear energy, including all the steps in the nuclear fuel cycle, results in the generation of radioactive waste. However, radioactive waste may also be generated by other activities such as medical, laboratory, research institution, or industrial use of radioisotopes and sealed radiation sources, defense and weapons programs, and processing (mostly large scale) of mineral ores or other materials containing naturally occurring radionuclides. Radioactive waste also arises from intervention activities, which are necessary after accidents or to remediate areas affected by past practices. The radioactive waste generated arises in a wide range of physical, chemical, and radiological forms. It may be solid, liquid, or gaseous. Levels of activity concentration can vary from extremely high, such as levels associated with spent fuel and residues from fuel reprocessing, to very low, for instance those associated with radioisotope applications. Equally broad is the spectrum of half-lives of the radionuclides contained in the waste. These differences result in an equally wide variety of

  15. Current Status of Japanese Global Precipitation Measurement (GPM) Research Project

    NASA Astrophysics Data System (ADS)

    Kachi, Misako; Oki, Riko; Kubota, Takuji; Masaki, Takeshi; Kida, Satoshi; Iguchi, Toshio; Nakamura, Kenji; Takayabu, Yukari N.

    2013-04-01

    The Global Precipitation Measurement (GPM) mission is a mission led by the Japan Aerospace Exploration Agency (JAXA) and the National Aeronautics and Space Administration (NASA) under collaboration with many international partners, who will provide constellation of satellites carrying microwave radiometer instruments. The GPM Core Observatory, which carries the Dual-frequency Precipitation Radar (DPR) developed by JAXA and the National Institute of Information and Communications Technology (NICT), and the GPM Microwave Imager (GMI) developed by NASA. The GPM Core Observatory is scheduled to be launched in early 2014. JAXA also provides the Global Change Observation Mission (GCOM) 1st - Water (GCOM-W1) named "SHIZUKU," as one of constellation satellites. The SHIZUKU satellite was launched in 18 May, 2012 from JAXA's Tanegashima Space Center, and public data release of the Advanced Microwave Scanning Radiometer 2 (AMSR2) on board the SHIZUKU satellite was planned that Level 1 products in January 2013, and Level 2 products including precipitation in May 2013. The Japanese GPM research project conducts scientific activities on algorithm development, ground validation, application research including production of research products. In addition, we promote collaboration studies in Japan and Asian countries, and public relations activities to extend potential users of satellite precipitation products. In pre-launch phase, most of our activities are focused on the algorithm development and the ground validation related to the algorithm development. As the GPM standard products, JAXA develops the DPR Level 1 algorithm, and the NASA-JAXA Joint Algorithm Team develops the DPR Level 2 and the DPR-GMI combined Level2 algorithms. JAXA also develops the Global Rainfall Map product as national product to distribute hourly and 0.1-degree horizontal resolution rainfall map. All standard algorithms including Japan-US joint algorithm will be reviewed by the Japan-US Joint

  16. Mission Need Statement for the Idaho National Laboratory Remote-Handled Low-Level Waste Disposal Project

    SciTech Connect

    Lisa Harvego

    2009-06-01

    The Idaho National Laboratory proposes to establish replacement remote-handled low-level waste disposal capability to meet Nuclear Energy and Naval Reactors mission-critical, remote-handled low-level waste disposal needs beyond planned cessation of existing disposal capability at the end of Fiscal Year 2015. Remote-handled low-level waste is generated from nuclear programs conducted at the Idaho National Laboratory, including spent nuclear fuel handling and operations at the Naval Reactors Facility and operations at the Advanced Test Reactor. Remote-handled low-level waste also will be generated by new programs and from segregation and treatment (as necessary) of remote-handled scrap and waste currently stored in the Radioactive Scrap and Waste Facility at the Materials and Fuels Complex. Replacement disposal capability must be in place by Fiscal Year 2016 to support uninterrupted Idaho operations. This mission need statement provides the basis for the laboratory’s recommendation to the Department of Energy to proceed with establishing the replacement remote-handled low-level waste disposal capability, project assumptions and constraints, and preliminary cost and schedule information for developing the proposed capability. Without continued remote-handled low-level waste disposal capability, Department of Energy missions at the Idaho National Laboratory would be jeopardized, including operations at the Naval Reactors Facility that are critical to effective execution of the Naval Nuclear Propulsion Program and national security. Remote-handled low-level waste disposal capability is also critical to the Department of Energy’s ability to meet obligations with the State of Idaho.

  17. Cellular chromophores and signaling in low level light therapy

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.; Demidova-Rice, Tatiana N.

    2007-02-01

    The use of low levels of visible or near infrared light (LLLT) for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage by reducing cellular apoptosis has been known for almost forty years since the invention of lasers. Originally thought to be a peculiar property of laser light (soft or cold lasers), the subject has now broadened to include photobiomodulation and photobiostimulation using non-coherent light. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. This likely is due to two main reasons; firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. In recent years major advances have been made in understanding the mechanisms that operate at the cellular and tissue levels during LLLT. Mitochondria are thought to be the main site for the initial effects of light and specifically cytochrome c oxidase that has absorption peaks in the red and near infrared regions of the electromagnetic spectrum matches the action spectra of LLLT effects. The discovery that cells employ nitric oxide (NO) synthesized in the mitochondria by neuronal nitric oxide synthase, to regulate respiration by competitive binding to the oxygen binding of cytochrome c oxidase, now suggests how LLLT can affect cell metabolism. If LLLT photodissociates inhibitory NO from cytochrome c oxidase, this would explain increased ATP production, modulation of reactive oxygen species, reduction and prevention of apoptosis, stimulation of angiogenesis, increase of blood flow and induction of transcription factors. In

  18. US Army facility for the consolidation of low-level radioactive waste

    SciTech Connect

    Stein, S.L.; Tanner, J.E.; Murphy, B.L.; Gillings, J.C.; Hadley, R.T.; Lyso, O.M.; Gilchrist, R.L.; Murphy, D.W.

    1983-12-01

    A preliminary study of a waste consolidation facility for the Department of the Army's low-level radioactive waste was carried out to determine a possible site and perform a cost-benefit analysis. Four sites were assessed as possible locations for such a facility, using predetermined site selection criteria. To assist in the selection of a site, an evaluation of environmental issues was included as part of each site review. In addition, a preliminary design for a waste consolidation facility was developed, and facilities at each site were reviewed for their availability and suitability for this purpose. Currently available processes for volume reduction, as well as processes still under development, were then investigated, and the support and handling equipment and the staff needed for the safe operation of a waste consolidation facility were studied. Using current costs for the transportation and burial of low-level waste, a cost comparison was then made between waste disposal with and without the utilization of volume reduction. Finally, regulations that could affect the operation of a waste consolidation facility were identified and their impact was assessed. 11 references, 5 figures, 16 tables.

  19. Effect of anthropogenic sulfate aerosols on low-level cloud albedo over oceans

    NASA Technical Reports Server (NTRS)

    Kim, Youngseung; Cess, Robert D.

    1993-01-01

    By reducing cloud droplet size, anthropogenic sulfate aerosols are capable of increasing cloud albedo and thus possibly changing the climate. To test the detectability of this effect, we examined satellite-measured low-level cloud albedo off the east coasts of North America and Asia at midlatitudes where anthropogenic sulfate sources are large and aerosols are transported eastward over the oceans by prevailing westerlies. The satellite data demonstrate enhanced cloud albedo near the coastal boundaries where sulfate concentrations are large. Similar trends are absent over ocean regions of the Southern Hemisphere that are removed from anthropogenic sulfate sources.

  20. Carotid-cardiac baroreflex influence on forearm vascular resistance during low level LBNP

    NASA Technical Reports Server (NTRS)

    Ludwig, David

    1990-01-01

    Twelve healthy males were tested at low levels of lower body negative pressure (LBNP) with and without artificial stimulation of the carotid-cardiac baroreceptors. The carotid-cardiac baroreceptors were stimulated by applying a pressure of 10 mmHg to the carotid artery via a pressurized neck chamber. During the procedure, forearm blood flow (FBF) and forearm vascular resistance (FVR) were measured using a Whitney mercury silastic strain gauge technique. FBF decreased while FVR increased with increased intensity of LBNP. Both FBF and FVR were unaffected by carotid-cardiac baroreceptor stimulation.

  1. Comparison of acoustic doppler current profiler and Price AA mechanical current meter measurements made during the 2011 Mississippi River Flood

    USGS Publications Warehouse

    O'Brien, Patrick; Mueller, David; Pratt, Thad

    2012-01-01

    The Mississippi River and Tributaries project performed as designed during the historic 2011 Mississippi River flood, with many of the operational decisions based on discharge targets as opposed to stage. Measurement of discharge at the Tarbert Landing, Mississippi range provides critical information used in operational decisions for the floodways located in Louisiana. Historically, discharge measurements have been made using a Price AA current meter and the mid-section method, and a long record exists based on these types of measurements, including historical peak discharges. Discharge measurements made using an acoustic Doppler current profiler from a moving boat have been incorporated into the record since the mid 1990's, and are used along with the Price AA mid-section measurements. During the 2011 flood event, both methods were used and appeared to provide different results at times. The apparent differences between the measurement techniques are due to complex hydrodynamics at this location that created large spatial and temporal fluctuations in the flow. The data and analysis presented herein show the difference between the two methods to be within the expected accuracy of the measurements when the measurements are made concurrently. The observed fluctuations prevent valid comparisons of data collected sequentially or even with different observation durations.

  2. The use of low-level laser therapy for controlling the gag reflex in children during intraoral radiography.

    PubMed

    Elbay, Mesut; Tak, Önjen; Şermet Elbay, Ülkü; Kaya, Can; Eryılmaz, Kubilay

    2016-02-01

    The current literature suggests that low-level laser stimulation of the PC 6 acupuncture points may prevent gagging. This study aimed to determine if low-level laser therapy (LLLT) can reduce the gag reflex in children undergoing intraoral maxillary radiography. This randomized, controlled, double-blind clinical trial was conducted with 25 children with moderate-to-very severe gag reflexes who required bilateral periapical radiographic examination of the maxillary molar region. Children's anxiety levels were initially evaluated using Corah's Dental Anxiety Scale (DAS) to identify any possible relationship between gagging and anxiety. A control radiograph was taken of one randomly selected side in each patient after simulated laser application so that the patient was blinded to the experimental conditions (control group). Laser stimulation was then performed for the experimental side. A laser probe was placed on the Pericardium 6 (PC 6) acupuncture point on each wrist, and laser energy was delivered for 14 s (300 mW, energy density 4 J/cm(2)) at a distance of 1 cm from the target tissue. Following laser stimulation, the experimental radiograph was taken (experimental group). Gagging responses were measured using the Gagging Severity Criteria for each group. Data were analyzed using Spearman's rho correlations and Mann-Whitney U tests. Both mean and median gagging scores were higher in the control group than in the experimental group. Patients who were unable to tolerate the intraoral control radiography were able to tolerate the procedure after LLLT. Differences between gagging scores of the control and experimental groups were statistically significant (P = .000). There was no significant correlation between gagging severity and anxiety score (P > .05). A negative correlation was found between age and gagging score in the control group (P ˂ .05). Within the limitations of this study, LLLT of the PC 6 acupuncture points appears to be a useful technique

  3. Biotic transport of radionuclides from a low-level radioactive waste site.

    PubMed

    Kennedy, W E; Cadwell, L L; McKenzie, D H

    1985-07-01

    In the United States, concern for human exposures to radioactivity associated with the disposal of low-level radioactive waste has resulted in a series of regulatory guides, environmental assessments, management practices, and modeling tools. A large number of radionuclide transport processes and mechanisms that may contribute to human exposure have been modeled, using computer programs to make the required calculations. The objective of our work was to evaluate the relevance of potential biological transport processes in the assessment of potential impacts at low-level waste (LLW) disposal sites. As part of this effort, we developed an order-of-magnitude estimate for potential dose to man resulting from biological transport by burrowing animals and by plant translocation at a reference low-level waste site in the arid west. We also made comparative dose-to-man estimates for a more commonly considered human intrusion exposure scenario. Parameter values for defining a reference arid LLW disposal site and biotic transport processes are based on data reported in current literature. Estimates of waste volumes for the western United States are based on information described by the U.S. Nuclear Regulatory Commission in the Draft Environmental Impact Statement in support of 10 CFR Part 61. Our estimates of the dose-to-man resulting from biotic transport are of the same order of magnitude as those resulting from a more commonly evaluated human intrusion scenario. The previously assumed lack of potential importance of biotic transport at LLW sites in earlier assessment studies is not confirmed by our findings. Our results indicate that long-term biological transport processes have the potential to influence LLW site performance, and should be carefully evaluated as part of the impact assessment process. PMID:4008258

  4. Alternatives To The Burial Of Low-Level Radioactive Waste

    SciTech Connect

    Price, J. Mark

    2008-01-15

    have been fully dismantled. Proven techniques and equipment are available to dismantle nuclear facilities safely. Most parts of a nuclear power plants do not become radioactive or are contaminated at very low levels and most metal can be recycled. There are obvious environmental benefits to the decontamination, recycle and reuse of materials. The benefits come primarily from the reduction of waste and eliminating the need to obtain fresh materials for the new product. The benefits of recycling in other industries are well recognized. Not having a waste management option can sometimes delay decommissioning of nuclear facilities. Therefore, the availability of a recycling route for the waste may accelerate decommissioning progress. With improving prospects for building new nuclear power plants, the industry would likely use the option if significant amounts of waste materials could be recycled economically. There is little consistency in national approaches to recycling radioactive waste. Many options for recycling allow for the release of materials into the public domain (after decontamination to allowable levels). There is not uniform endorsement of this practice from country to country and some stakeholders do not agree with this type of material release (often reduced to as unconditional release). There is a large amount of material that can have conditional release within the industry that assures consistent endorsement by stakeholders. This material includes: concrete, lead, carbon and stainless steel, and graphite. More work needs to be done to ensure consistency in regulation from country to country. The IAEA is working to this end.

  5. Preliminary analysis of the ORNL Liquid Low-Level Waste system

    SciTech Connect

    Abraham, T.J.; DePaoli, S.M.; Robinson, S.M.; Walker, A.B.

    1994-08-01

    The objective of this report is to summarize the status of the Liquid Low-Level Waste (LLLW) Systems Analysis project. The focus of this project has been to collect and tabulate data concerning the LLLW system, analyze the current LLLW system operation, and develop the information necessary for the development of long-term treatment options for the LLLW generated at ORNL. The data used in this report were collected through a survey of Oak Ridge National Laboratory (ORNL) literature, various letter reports, and a survey of all current LLLW generators. These data are also being compiled in a user friendly database for ORNL-wide distribution. The database will allow the quick retrieval of all information collected on the ORNL LLLW system and will greatly benefit any LLLW analysis effort. This report summarizes the results for the analyses performed to date on the LLLW system.

  6. Performance of current measurement system in poloidal field power supply for Experimental Advanced Superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Liu, D. M.; Li, J.; Wan, B. N.; Lu, Z.; Wang, L. S.; Jiang, L.; Lu, C. H.; Huang, J.

    2016-11-01

    As one of the core subsystems of the Experimental Advanced Superconducting Tokamak (EAST), the poloidal field power system supplies energy to EAST's superconducting coils. To measure the converter current in the poloidal field power system, a current measurement system has been designed. The proposed measurement system is composed of a Rogowski coil and a newly designed integrator. The results of the resistor-inductor-capacitor discharge test and the converter equal current test show that the current measurement system provides good reliability and stability, and the maximum error of the proposed system is less than 1%.

  7. 1989 Annual report on low-level radioactive waste management progress

    SciTech Connect

    Not Available

    1990-10-01

    This report summarizes the progress during 1989 of states and compacts in establishing new low-level radioactive waste disposal facilities. It also provides summary information on the volume of low-level waste received for disposal in 1989 by commercially operated low-level waste disposal facilities. This report is in response to Section 7(b) of Title I of Public Law 99--240, the Low-Level Radioactive Waste Policy Amendments Act of 1985. 2 figs., 5 tabs.

  8. Commercial low-level radioactive waste transportation liability and radiological risk

    SciTech Connect

    Quinn, G.J.; Brown, O.F. II; Garcia, R.S.

    1992-08-01

    This report was prepared for States, compact regions, and other interested parties to address two subjects related to transporting low-level radioactive waste to disposal facilities. One is the potential liabilities associated with low-level radioactive waste transportation from the perspective of States as hosts to low-level radioactive waste disposal facilities. The other is the radiological risks of low-level radioactive waste transportation for drivers, the public, and disposal facility workers.

  9. E AREA LOW LEVEL WASTE FACILITY DOE 435.1 PERFORMANCE ASSESSMENT

    SciTech Connect

    Wilhite, E

    2008-03-31

    This Performance Assessment for the Savannah River Site E-Area Low-Level Waste Facility was prepared to meet requirements of Chapter IV of the Department of Energy Order 435.1-1. The Order specifies that a Performance Assessment should provide reasonable assurance that a low-level waste disposal facility will comply with the performance objectives of the Order. The Order also requires assessments of impacts to water resources and to hypothetical inadvertent intruders for purposes of establishing limits on radionuclides that may be disposed near-surface. According to the Order, calculations of potential doses and releases from the facility should address a 1,000-year period after facility closure. The point of compliance for the performance measures relevant to the all pathways and air pathway performance objective, as well as to the impact on water resources assessment requirement, must correspond to the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste following the assumed end of active institutional controls 100 years after facility closure. During the operational and institutional control periods, the point of compliance for the all pathways and air pathway performance measures is the SRS boundary. However, for the water resources impact assessment, the point of compliance remains the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste during the operational and institutional control periods. For performance measures relevant to radon and inadvertent intruders, the points of compliance are the disposal facility surface for all time periods and the disposal facility after the assumed loss of active institutional controls 100 years after facility closure, respectively. The E-Area Low-Level Waste Facility is located in the central region of the SRS known as the General Separations Area. It is an elbow-shaped, cleared area, which curves to the northwest

  10. Life-Cycle Cost Study for a Low-Level Radioactive Waste Disposal Facility in Texas

    SciTech Connect

    B. C. Rogers; P. L. Walter; R. D. Baird

    1999-08-01

    This report documents the life-cycle cost estimates for a proposed low-level radioactive waste disposal facility near Sierra Blanca, Texas. The work was requested by the Texas Low-Level Radioactive Waste Disposal Authority and performed by the National Low-Level Waste Management Program with the assistance of Rogers and Associates Engineering Corporation.

  11. Cytomorphological changes in buccal mucosa of patients treated with low-level 1,064-nm laser radiation.

    PubMed

    Sezer, Ufuk; Aras, Mutan Hamdi; Aktan, Ali Murat; Cengiz, Beyhan; Ozkul, Nadide; Ay, Sinan

    2012-01-01

    The aim of this study was to examine the cytomorphological changes occurring in the buccal mucosa in patients treated with low-level 1,064-nm laser radiation. Seventeen individuals (12 males, five females) 18-24 years of age were included in the study. Low-level 1,064-nm laser radiation was applied to the right buccal mucosa near the premolar region; this therapy was repeated for 10 days. Buccal epithelial cells were collected from the right and left premolar regions of the individuals with a brush before and after therapy. The specimens collected from the left side were measured cytomorphometrically and used for the control group. Student's t test was used for statistical comparison of the values of the buccal epithelial cells collected from individuals; a p value < 0.05 was considered statistically significant. None of the patients showed any adverse reactions to the low-level 1,064-nm laser radiation therapy during application. There was no cytogenetic damage to the therapied or non-therapied regions in the buccal mucosa cells, as determined cytomorphologically. The results suggest that low-level 1,064-nm laser radiation therapy has no genotoxic potential. Within the limitations of this study, it can be concluded that low-level 1,064-nm laser radiation therapy may be used safely in dental treatments.

  12. RF low-level control for the Linac4 H{sup −} source

    SciTech Connect

    Butterworth, A. Grudiev, A.; Lettry, J.; Paoluzzi, M.; Schmitzer, C.; Nishida, K.

    2015-04-08

    The H{sup −} source for the Linac4 accelerator at CERN uses an RF driven plasma for the production of H{sup −}. The RF is supplied by a 2 MHz RF tube amplifier with a maximum power output of 100 kW and a pulse duration of up to 2 ms. The low-level RF signal generation and measurement system has been developed using standard CERN controls electronics in the VME form factor. The RF frequency and amplitude reference signals are generated using separate arbitrary waveform generator channels. The frequency and amplitude are both freely programmable over the duration of the RF pulse, which allows fine-tuning of the excitation. Measurements of the forward and reverse RF power signals are performed via directional couplers using high-speed digitizers, and permit the estimation of the plasma impedance and deposited power via an equivalent circuit model. The low-level RF hardware and software implementations are described, and experimental results obtained with the Linac4 ion sources in the test stand are presented.

  13. Depth of penetration of an 850nm wavelength low level laser in human skin.

    PubMed

    Esnouf, Alan; Wright, Philip A; Moore, Joan C; Ahmed, Salim

    2007-01-01

    Low Level Laser Therapy is used for a wide variety of conditions including superficial skin sores, musculoskeletal and joint problems, and dentistry. Knowledge of the penetration depth of laser radiation in human skin is an essential prerequisite to identifying its method of action. Mathematical simulations and estimates from the literature suggest that the depth of penetration of laser radiation using wavelengths from 630nm up to 1100nm may be up to 50mm. The aim of this study is to directly measure the penetration depth of a Low Level Laser in human tissue. Human abdominal skin samples up to 0.784mm thickness were harvested by dermatome following abdominoplasty procedures. These samples were irradiated by a Gallium Aluminium Arsenide Laser (Wavelength 850nm near infra-red invisible light, 100mW, 24kHz, 0.28mm diameter probe) and the transmitted radiation measured with an Ophir Optronics 'Nova' external energy meter. The intensity of laser radiation reduced by 66% after being transmitted through a 0.784mm sample of human abdominal tissue. In this study most laser radiation was absorbed within the first 1mm of skin.

  14. Low-level tank waste simulant data base

    SciTech Connect

    Lokken, R.O.

    1996-04-01

    The majority of defense wastes generated from reprocessing spent N- Reactor fuel at Hanford are stored in underground Double-shell Tanks (DST) and in older Single-Shell Tanks (SST) in the form of liquids, slurries, sludges, and salt cakes. The tank waste remediation System (TWRS) Program has the responsibility of safely managing and immobilizing these tank wastes for disposal. This report discusses three principle topics: the need for and basis for selecting target or reference LLW simulants, tanks waste analyses and simulants that have been defined, developed, and used for the GDP and activities in support of preparing and characterizing simulants for the current LLW vitrification project. The procedures and the data that were generated to characterized the LLW vitrification simulants were reported and are presented in this report. The final section of this report addresses the applicability of the data to the current program and presents recommendations for additional data needs including characterization and simulant compositional variability studies.

  15. Management of Low-Level Radioactive Waste from Research, Hospitals and Nuclear Medical Centers in Egypt - 13469

    SciTech Connect

    Hasan, M.A.; Selim, Y.T.; Lasheen, Y.F.

    2013-07-01

    The application of radioisotopes and radiation sources in medical diagnosis and therapy is an important issue. Physicians can use radioisotopes to diagnose and treat diseases. Methods of treatment, conditioning and management of low level radioactive wastes from the use of radiation sources and radioisotopes in hospitals and nuclear medicine application, are described. Solid Radioactive waste with low-level activity after accumulation, minimization, segregation and measurement, are burned or compressed in a compactor according to the international standards. Conditioned drums are transported to the interim storage site at the Egyptian Atomic Energy Authority (EAEA) represented in Hot Labs and Waste Management Center (HLWMC) for storage and monitoring. (authors)

  16. Los Alamos low-level waste performance assessment status

    SciTech Connect

    Wenzel, W.J.; Purtymun, W.D.; Dewart, J.M.; Rodgers, J.E.

    1986-06-01

    This report reviews the documented Los Alamos studies done to assess the containment of buried hazardous wastes. Five sections logically present the environmental studies, operational source terms, transport pathways, environmental dosimetry, and computer model development and use. This review gives a general picture of the Los Alamos solid waste disposal and liquid effluent sites and is intended for technical readers with waste management and environmental science backgrounds but without a detailed familiarization with Los Alamos. The review begins with a wide perspective on environmental studies at Los Alamos. Hydrology, geology, and meteorology are described for the site and region. The ongoing Laboratory-wide environmental surveillance and waste management environmental studies are presented. The next section describes the waste disposal sites and summarizes the current source terms for these sites. Hazardous chemical wastes and liquid effluents are also addressed by describing the sites and canyons that are impacted. The review then focuses on the transport pathways addressed mainly in reports by Healy and Formerly Utilized Sites Remedial Action Program. Once the source terms and potential transport pathways are described, the dose assessment methods are addressed. Three major studies, the waste alternatives, Hansen and Rogers, and the Pantex Environmental Impact Statement, contributed to the current Los Alamos dose assessment methodology. Finally, the current Los Alamos groundwater, surface water, and environmental assessment models for these mesa top and canyon sites are described.

  17. Quantification of low levels of amorphous content in crystalline celecoxib using dynamic vapor sorption (DVS).

    PubMed

    Sheokand, Sneha; Modi, Sameer R; Bansal, Arvind K

    2016-05-01

    A minor amount of amorphous phase, especially present on the surface of crystalline pharmaceutical actives, can have a significant impact on their processing and performance. Despite the presence of sophisticated analytical tools, detection and quantification of low levels of amorphous content pose significant challenges owing to issues of sensitivity, suitability, limit of detection and limit of quantitation. Current study encompasses the quantification of amorphous content in the crystalline form of celecoxib (CLB) using a dynamic vapor sorption (DVS) based method. Water, used as the solvent probe, achieved equilibration within a very short period of time (i.e. 6h) due to hydrophobic nature of CLB, thus allowing development of a rapid quantification method. The study included optimization of instrument and sample related parameters for the development of an analytical method. The calibration curve for amorphous CLB in crystalline CLB was prepared in the concentration range of 0-10% w/w. The analytical method was validated for linearity, range, accuracy and precision. The method for quantification was found to be linear with R(2) value of 0.999, rapid and sensitive for quantification of low levels of amorphous CLB content. It was able to detect the presence of amorphous phase in a predominantly crystalline phase at concentrations as low as 0.3% w/w. The limit of quantitation was found to be 0.9% w/w. Moreover, the influence of mechanical processing on the amorphous content in crystalline CLB was also investigated. PMID:26948976

  18. FLILO (flying infrared for low-level operations): an enhanced vision system

    NASA Astrophysics Data System (ADS)

    Guell, Jeff J.

    2000-06-01

    FLILO is an Enhanced Vision System (EVS); which enhances Situational Awareness for safe low level/night time and moderate weather flight operations (including: take- off/landing, taxiing, approaches, drop zone identification, Short Austere Air Field operations, etc), by providing electronic/real time vision to the pilots. It consists of a series of imaging sensors, an Image Processor and a wide field-of-view (FOV) see-through Helmet Mounted Display (HMD) integrated with a Head Tracker. The current solution for safe night time/low level military flight operations is the use of the Turret-FLIR (Forward-Looking InfraRed). This system requires an additional operator/crew member (navigator) who controls the Turret's movement and relays the information to the pilots. The image is presented on a Head-Down-Display. FLILO presents the information directly to the pilots on an HMD, therefore each pilot has an independent view controlled by their heads position, while utilizing the same sensors that are static and fixed to the aircraft structure. Since there are no moving parts, the system provides high reliability, while remaining more affordable than the Turret-FLIR solution. FLILO does not require a ball-turret, therefore there is no extra drag or range impact on the aircraft's performance. Furthermore, with future use of real-time multi-band/multi-sensor image fusion, FLILO is the right step towards obtaining safe autonomous landing guidance/0-0 flight operations capability.

  19. Vitrification as a low-level radioactive mixed waste treatment technology at Argonne National Laboratory

    SciTech Connect

    Mazer, J.J.; No, Hyo J.

    1995-08-01

    Argonne National Laboratory-East (ANL-E) is developing plans to use vitrification to treat low-level radioactive mixed wastes (LLMW) generated onsite. The ultimate objective of this project is to install a full-scale vitrification system at ANL-E capable of processing the annual generation and historic stockpiles of selected LLMW streams. This project is currently in the process of identifying a range of processible glass compositions that can be produced from actual mixed wastes and additives, such as boric acid or borax. During the formulation of these glasses, there has been an emphasis on maximizing the waste content in the glass (70 to 90 wt %), reducing the overall final waste volume, and producing a stabilized low-level radioactive waste glass. Crucible glass studies with actual mixed waste streams have produced alkali borosilicate glasses that pass the Toxic Characteristic Leaching Procedure (TCLP) test. These same glass compositions, spiked with toxic metals well above the expected levels in actual wastes, also pass the TCLP test. These results provide compelling evidence that the vitrification system and the glass waste form will be robust enough to accommodate expected variations in the LLMW streams from ANL-E. Approximately 40 crucible melts will be studied to establish a compositional envelope for vitrifying ANL-E mixed wastes. Also being determined is the identity of volatilized metals or off-gases that will be generated.

  20. Scoping evaluation of the technical capabilities of DOE sites for disposal of hazardous metals in mixed low-level waste

    SciTech Connect

    Gruebel, M.M.; Waters, R.D.; Langkopf, B.S.

    1997-05-01

    A team of analysts designed and conducted a scoping evaluation to estimate the technical capabilities of fifteen Department of Energy sites for disposal of the hazardous metals in mixed low-level waste (i.e., waste that contains both low-level radioactive materials and hazardous constituents). Eight hazardous metals were evaluated: arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver. The analysis considered transport only through the groundwater pathway. The results are reported as site-specific estimates of maximum concentrations of each hazardous metal in treated mixed low-level waste that do not exceed the performance measures established for the analysis. Also reported are site-specific estimates of travel times of each hazardous metal to the point of compliance.

  1. Mechanisms and pathophysiology of the low-level blast brain injury in animal models.

    PubMed

    Säljö, Annette; Mayorga, Maria; Bolouri, Hayde; Svensson, Berndt; Hamberger, Anders

    2011-01-01

    The symptoms of primary blast-induced mTBI, posttraumatic stress disorder and depression overlap. Evidence of an organic basis for these entities has been scarce and controversial. We present a review of animal studies demonstrating that low-level blast causes pathophysiological and functional changes in the brain. We monitor a time period from minutes to approximately 1 week after blast exposure from multiple modes (air, underwater, localized and whole body). The most salient findings observed were (1) the peak pressures (P(max)) in the brain, elicited from the blast from the firing of military weapons (P(max) 23-45 kPa), have a similar magnitude as that registered in air close to the head. Corresponding measurements during the detonation pulse from explosives under water show a P(max) in the brain, which is only 10% of that in water outside the head. (2) The rise time of the pressure curve is 10 times longer in the brain as compared with the blast in air outside the head during firing of military weapons. (3) The lower frequencies in the blast wave appear to be transmitted more readily to the brain than the higher frequencies. (4) When animals are exposed to low levels of blast, the blast wave appears mostly transmitted directly to the brain during air exposure, not via the thorax or abdomen. (5) Low levels of blast cause brain edema, as indicated by increased bioelectrical impedance, an increase in the intracranial pressure, small brain hemorrhages and impaired cognitive function. PMID:20580846

  2. An Investigation of Topography Modulated Low Level Moisture Convergence Patterns in the Southern Appalachians Using WRF

    NASA Astrophysics Data System (ADS)

    Wilson, A. M.; Duan, Y.; Barros, A.

    2015-12-01

    The Southern Appalachian Mountains (SAM) region is a biodiversity hot-spot that is vulnerable to land use/land cover changes due to its proximity to the rapidly growing population in the Southeast U.S. Persistent near surface moisture and associated microclimates observed in this region have been documented since the colonization of the area. The landform in this area, in particular in the inner mountain region, is highly complex with nested valleys and ridges. The geometry of the terrain causes distinct diurnal and seasonal local flow patterns that result in highly complex interactions of this low level moisture with meso- and synoptic-scale cyclones passing through the region. The Weather Research and Forecasting model (WRF) was used to conduct high resolution simulations of several case studies of warm season precipitation in the SAM with different synoptic-scale conditions to investigate this interaction between local and larger-scale flow patterns. The aim is to elucidate the microphysical interactions among these shallow orographic clouds and preexisting precipitating cloud systems and identify uncertainties in the model microphysics using in situ measurements. Findings show that ridge-valley precipitation gradients, in particular the "reverse" to the classical orographic effect observed in inner mountain valleys, is linked to horizontal heterogeneity in the vertical structure of low level cloud and precipitation promoted through landform controls on local flow. Moisture convergence patterns follow the peaks and valleys as represented by WRF terrain, and the topography effectively controls their timing and spatial structure. The simulations support the hypothesis that ridge-valley precipitation gradients, and in particular the reverse orographic enhancement effect in inner mountain valleys, is linked to horizontal heterogeneity in the vertical structure of low level clouds and precipitation promoted through landform controls on moisture convergence.

  3. Effect of low-level laser therapy on tooth sensitivity induced by in-office bleaching.

    PubMed

    Moosavi, Horieh; Arjmand, Nooshin; Ahrari, Farzaneh; Zakeri, Majid; Maleknejad, Fatemeh

    2016-05-01

    This study aimed to investigate the effect of low-level laser therapy (LLLT) on tooth sensitivity induced by in-office bleaching. Sixty-six patients enrolled in this randomized clinical trial. Following the in-office procedure with 40% hydrogen peroxide, the participants were randomly divided into three groups. The patients in group 1 received irradiation from a low-level red laser (LLRL; 660 nm, 200 mW, 15 s, 12 J/cm(2)), whereas participants in group 2 were subjected to a low-level infrared laser (LLIL; 810 nm) under similar conditions as in group 1. In group 3 (placebo), the laser treatment was the same as that in groups 1 and 2, but without energy output. The degree of tooth sensitivity was recorded at 1, 24, and 48 h after bleaching using a visual analog scale (VAS). The change in tooth shade was measured 30 days after tooth whitening. The intensity of tooth sensitivity was not significantly different between groups at 1 h after bleaching (p > 0.05). At 24 h after therapy, pain level was significantly lower in the LLIL group compared to the LLRL and placebo groups (p < 0.05). At 48 h after bleaching, VAS scores in the LLIL and LLRL groups were comparable to each other (p > 0.05) and both were significantly lower than that of the placebo group (p < 0.05). There was no significant difference in the efficacy of tooth whitening among groups (p > 0.05). LLLT with an infrared diode laser could be recommended as a suitable strategy to reduce the intensity of tooth sensitivity after in-office bleaching. PMID:26964798

  4. Effect of low-level laser therapy on tooth sensitivity induced by in-office bleaching.

    PubMed

    Moosavi, Horieh; Arjmand, Nooshin; Ahrari, Farzaneh; Zakeri, Majid; Maleknejad, Fatemeh

    2016-05-01

    This study aimed to investigate the effect of low-level laser therapy (LLLT) on tooth sensitivity induced by in-office bleaching. Sixty-six patients enrolled in this randomized clinical trial. Following the in-office procedure with 40% hydrogen peroxide, the participants were randomly divided into three groups. The patients in group 1 received irradiation from a low-level red laser (LLRL; 660 nm, 200 mW, 15 s, 12 J/cm(2)), whereas participants in group 2 were subjected to a low-level infrared laser (LLIL; 810 nm) under similar conditions as in group 1. In group 3 (placebo), the laser treatment was the same as that in groups 1 and 2, but without energy output. The degree of tooth sensitivity was recorded at 1, 24, and 48 h after bleaching using a visual analog scale (VAS). The change in tooth shade was measured 30 days after tooth whitening. The intensity of tooth sensitivity was not significantly different between groups at 1 h after bleaching (p > 0.05). At 24 h after therapy, pain level was significantly lower in the LLIL group compared to the LLRL and placebo groups (p < 0.05). At 48 h after bleaching, VAS scores in the LLIL and LLRL groups were comparable to each other (p > 0.05) and both were significantly lower than that of the placebo group (p < 0.05). There was no significant difference in the efficacy of tooth whitening among groups (p > 0.05). LLLT with an infrared diode laser could be recommended as a suitable strategy to reduce the intensity of tooth sensitivity after in-office bleaching.

  5. Application of Low-Level Laser Therapy Following Coronary Artery Bypass Grafting (CABG) Surgery

    PubMed Central

    Babazadeh, Kamran; Lajevardi, Marjan; Dabaghian, Fataneh Hashem; Mostafavi, Ehsan

    2014-01-01

    Introduction: An attack of acute myocardial infarction (MI) poses the threat of great damage to cardiac tissue. Operative therapeutic modalities such as coronary artery bypass grafting (CABG) may enhance myocardial perfusion in high-grade coronary vasculature occlusions. It has been shown previously that Low-Level Laser Therapy (LLLT) significantly reduces infarct size following induction of myocardial infarction in rats and dogs. The aim of this study was to investigate the effects of LLLT on cardiac tissue healing markers following grafting operations for coronary vessel occlusion. Methods: Thirty-two cases having each two or three coronary vessel occlusions (2VD/3VD) underwent low-level laser therapy post-CABG, and 28 patients who did not undergo laser therapy were studied as a control group. Diode laser (810 nm, 500 mW) was used as LLLT protocol for 3 successive days post-CABG. Repeated measurements of blood cell count (CBC) and cardiac damage markers (CPK, CPK-MB, LDH) attained before CABG and during the 5 days of LLLT post-operatively, taken at one and 12 hours after daily laser irradiation. Results: In a comparison of the mean levels of the control and laser group, the variables were statistically different on 5th day after intervention for WBC, Neutrophil and Lymphocyte counts and WBC and lymphocyte changes. A statistically significant difference was seen in changes of CPK, CPK-mb and LDH over time P<0.001. Conclusion: It is concluded that low-level laser irradiation after CABG surgery could decrease cardiac cellular damage and help accelerate the repair of cardiac tissue post-operatively. This may lower post-operative disability as well as bed rest period in these patients. PMID:25653805

  6. A novel approach for automated shoreline extraction from remote sensing images using low level programming

    NASA Astrophysics Data System (ADS)

    Rigos, Anastasios; Vaiopoulos, Aristidis; Skianis, George; Tsekouras, George; Drakopoulos, Panos

    2015-04-01

    . Although simple, with minimal human interaction and low level programming, this method can provide precise coastlines with just one pixel resolution. Images covering more locations are currently under consideration.

  7. Calibration and characterization of a low level waste assay system

    SciTech Connect

    Giesler, G.C.; Henry, S.A.; Johnson, S.L.; Vehar, D.W.

    1993-12-31

    In today`s rapidly changing regulatory environment, increasingly detailed information is required about the composition of items intended for disposal. We have examined a system that can be used to measure the radioactivity in a container of waste destined for disposal. In order to better understand the capabilities and limitations of the system, we performed a number of measurements to calibrate and characterize this system. The results of this characterization including detectability limits for {sup 235}U and {sub 239}Pu are presented.

  8. Global Climatology of the Coastal Low-Level Wind Jets using different Reanalysis

    NASA Astrophysics Data System (ADS)

    Lima, Daniela C. A.; Soares, Pedro M. M.; Semedo, Alvaro; Cardoso, Rita M.

    2016-04-01

    Coastal Low-Level Jets (henceforth referred to as "coastal jets" or simply as CLLJ) are low-tropospheric mesoscale wind features, with wind speed maxima confined to the marine atmospheric boundary layer (MABL), typically bellow 1km. Coastal jets occur in the eastern flank of the semi-permanent subtropical mid-latitude high pressure systems, along equatorward eastern boundary currents, due to a large-scale synoptic forcing. The large-scale synoptic forcing behind CLLJ occurrences is a high pressure system over the ocean and a thermal low inland. This results in coastal parallel winds that are the consequence of the geostrophic adjustment. CLLJ are found along the California (California-Oregon) and the Canary (Iberia and Northeastern Africa) currents in the Northern Hemisphere, and along the Peru-Humboldt (Peru-Chile), Benguela (Namibia) and Western Australia (West Australia) currents in the Southern Hemisphere. In the Arabian Sea (Oman CLLJ), the interaction between the high pressure over the Indian Ocean in summer (Summer Indian Monsoon) and the Somali (also known as Findlater) Jet forces a coastal jet wind feature off the southeast coast of Oman. Coastal jets play an important role in the regional climates of the mid-latitude western continental regions. The decrease of the sea surface temperatures (SST) along the coast due to upwelling lowers the evaporation over the ocean and the coast parallel winds prevents the advection of marine air inshore. The feedback processes between the CLLJ and upwelling play a crucial role in the regional climate, namely, promoting aridity since the parallel flow prevents the intrusion of moisture inland, and increasing fish stocks through the transport of rich nutrient cold water from the bottom. In this study, the global coastal low-level wind jets are identified and characterized using an ensemble of three reanalysis, the ECMWF Interim Reanalysis (ERA-Interim), the Japanese 55-year Reanalysis (JRA-55) and the NCEP Climate Forecast

  9. Half-year-long measurements with a buoy-mounted acoustic Doppler current profiler in the Somali Current

    NASA Astrophysics Data System (ADS)

    Schott, Friedrich; Johns, William

    1987-05-01

    A self-contained, upward-looking acoustic Doppler current profiler (ADCP), mounted in the top float of a subsurface mooring was deployed in the Somali Current at 2°14'N, 45°55'E from September 17, 1985, to April 25, 1986. The instrument operated at a frequency of 150 kHz, with a vertical beam angle of 20°. Vector-averaged profiles of horizontal and vertical velocity were recorded every 4 hours, using 200 pings per ensemble at a vertical bin length of 8.7 m. The mooring was deployed in very rough topography, settling in a trough at 337 m depth with the ADCP located at 267 m depth. Data retrieval over the entire recording period was complete, with Doppler biasing from side lobe reception of vertically traveling rays affecting only the top 20 m below the surface. Over the 7-month deployment the instrument recorded current profiles encompassing the end of the 1985 summer monsoon and entire winter monsoon and also through the spring transition into the early onset phase of the 1986 summer monsoon. Significant echo amplitude variations of week-to-month-long duration were observed, which were only partially related to horizontal flow variations associated with the monsoons. Projection of the strong horizontal currents (exceeding 150 cm/s at times) into the vertical component was not observed, attesting to fairly exact orientation of the four beams and tilt meters. This indicates that the vertical current measurement from ADCPs can be potentially useful for phenomena with vertical velocities exceeding a few millimeters per second. However, an analysis of echo amplitude and vertical current variations at the diurnal period suggests that the measured vertical velocity is, at least at that period, probably dominated by active vertical migration of biological scatterers through the water column.

  10. Sunlight effects on the 3D polar current system determined from low Earth orbit measurements

    NASA Astrophysics Data System (ADS)

    Laundal, Karl M.; Finlay, Christopher C.; Olsen, Nils

    2016-08-01

    Interaction between the solar wind and the Earth's magnetosphere is associated with large-scale currents in the ionosphere at polar latitudes that flow along magnetic field lines (Birkeland currents) and horizontally. These current systems are tightly linked, but their global behaviors are rarely analyzed together. In this paper, we present estimates of the average global Birkeland currents and horizontal ionospheric currents from the same set of magnetic field measurements. The magnetic field measurements, from the low Earth orbiting Swarm and CHAMP satellites, are used to co-estimate poloidal and toroidal parts of the magnetic disturbance field, represented in magnetic apex coordinates. The use of apex coordinates reduces effects of longitudinal and hemispheric variations in the Earth's main field. We present global currents from both hemispheres during different sunlight conditions. The results show that the Birkeland currents vary with the conductivity, which depends most strongly on solar EUV emissions on the dayside and on particle precipitation at pre-midnight magnetic local times. In sunlight, the horizontal equivalent current flows in two cells, resembling an opposite ionospheric convection pattern, which implies that it is dominated by Hall currents. By combining the Birkeland current maps and the equivalent current, we are able to calculate the total horizontal current, without any assumptions about the conductivity. We show that the total horizontal current is close to zero in the polar cap when it is dark. That implies that the equivalent current, which is sensed by ground magnetometers, is largely canceled by the horizontal closure of the Birkeland currents.

  11. Review of private sector and Department of Energy treatment, storage, and disposal capabilities for low-level and mixed low-level waste

    SciTech Connect

    Willson, R.A.; Ball, L.W.; Mousseau, J.D.; Piper, R.B.

    1996-03-01

    Private sector capacity for treatment, storage, and disposal (TSD) of various categories of radioactive waste has been researched and reviewed for the Idaho National Engineering Laboratory (INEL) by Lockheed Idaho Technologies Company, the primary contractor for the INEL. The purpose of this document is to provide assistance to the INEL and other US Department of Energy (DOE) sites in determining if private sector capabilities exist for those waste streams that currently cannot be handled either on site or within the DOE complex. The survey of private sector vendors was limited to vendors currently capable of, or expected within the next five years to be able to perform one or more of the following services: low-level waste (LLW) volume reduction, storage, or disposal; mixed LLW treatment, storage, or disposal; alpha-contaminated mixed LLW treatment; LLW decontamination for recycling, reclamation, or reuse; laundering of radioactively-contaminated laundry and/or respirators; mixed LLW treatability studies; mixed LLW treatment technology development. Section 2.0 of this report will identify the approach used to modify vendor information from previous revisions of this report. It will also illustrate the methodology used to identify any additional companies. Section 3.0 will identify, by service, specific vendor capabilities and capacities. Because this document will be used to identify private sector vendors that may be able to handle DOE LLW and mixed LLW streams, it was decided that current DOE capabilities should also be identified. This would encourage cooperation between DOE sites and the various states and, in some instances, may result in a more cost-effective alternative to privatization. The DOE complex has approximately 35 sites that generate the majority of both LLW and mixed LLW. Section 4.0 will identify these sites by Operations Office, and their associated LLW and mixed LLW TSD units.

  12. Site characterization and performance assessment for a low level radioactive waste management site in the American Southwest

    SciTech Connect

    Shott, G.J.; Sully, M.J.; Muller, C.J.; Hammermeister, D.P.; Ginanni, J.M.

    1995-12-31

    The Area 5 Radioactive Waste Management Site, located 105 km northwest of the city of Las Vegas in southern Nevada, has been used for the disposal of low level radioactive waste since 1961. Site characterization studies have measured the physical, hydrologic and geochemical properties of core samples collected from 10 shallow boreholes and 3 deep boreholes that extend through the unsaturated zone to the uppermost aquifer. Results indicate that the unsaturated zone consists of 240 m of dry alluvial sediments and is remarkably uniform with respect to most physical parameters. Measurements of saturated hydraulic conductivity with depth showed no evidence of trends, layering or anisotropy. Water potential profiles indicate that water movement in the upper alluvium is upward except immediately following a precipitation event. Below the evaporative zone, the liquid flux was downward and of the same order of magnitude as the upward thermal vapor flux induced by the geothermal gradient. The extreme climatic conditions at the site reduce or eliminate many radionuclide release and transport mechanisms. Downward transport of radionuclides to the uppermost aquifer appears unlikely under current climatic conditions. Important radionuclide transport pathways appear to be limited to upward diffusion and advection of gases and biologically mediated transport. Conceptual models of disposal site performance have been developed based on site characterization studies. The limited transport pathways and limited land use potential of the site provide reasonable assurance that regulatory performance objectives can be meet.

  13. Uranium recovery from low-level aqueous sources. [76 references

    SciTech Connect

    Kelmers, A.D.; Goeller, H.E.

    1981-03-01

    The aqueous sources of soluble uranium were surveyed and evaluated in terms of the uranium geochemical cycle in an effort to identify potential unexploited resources. Freshwater sources appeared to be too low in uranium content to merit consideration, while seawater, although very dilute (approx. 3.3 ppB), contains approx. 4 x 10/sup 9/ metric tons of uranium in all the world's oceans. A literature review of recent publications and patents concerning uranium recovery from seawater was conducted. Considerable experimental work is currently under way in Japan; less is being done in the European countries. An assessment of the current state of technology is presented in this report. Repeated screening programs have identified hydrous titanium oxide as the most promising candidate absorbent. However, some of its properties such as distribution coefficient, selectivity, loading, and possibly stability appear to render its use inadequate in a practical recovery system. Also, various assessments of the energy efficiency of pumped or tidal power schemes for contacting the sorbent and seawater are in major disagreement. Needed future research and development tasks are discussed. A fundamental sorbent development program to greatly improve sorbent properties would be required to permit practical recovery of uranium from seawater. Major unresolved engineering aspects of such recovery systems are also identified and discussed.

  14. Application of spectral summing to indeterminate suspect low-level drums at Los Alamos National Laboratory

    SciTech Connect

    Gruetzmacher, Kathleen M; Veilleux, John M; Lucero, Randy P; Seamans, Jr, J. V.; Clapham, M. J.

    2011-01-27

    The spectral summing technique developed by Pajarito Scientific Corporation (PSC) is a unique modeling technique that is being employed by the Waste Disposition Project - Low Level Waste Disposition (WDP-LLWD) Group at Los Alamos National Laboratory (LANL). This technique has been used to disposition low-level radioactive waste that has dropped out of the transuranic (TRU) category and has no disposal path unless it can be proven to be LLW and not TRU. The TRU program at LANL run by Mobile Characterization Services (MCS) employs High Efficiency Neutron Counters (HENC) with built-in gamma assay systems to assay radioactive waste for shipment and disposal as TRU waste at the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico. As well as being certified for WIPP assays, the HENC systems can also be used for low-level waste assays for disposal at LANL or off-site disposal facilities, such as the Nevada Test Site (NTS). Some of the waste processed through the HENC systems cannot be confirmed TRU due to the absence of detected TRU alpha emitters above the TRU cutoff of 100 nCi/g. This waste becomes suspect low-level waste (SLLW). In many cases, the waste also can't be classified as LLW because the minimum detectable activity (MDA) of TRU radionuclides is above the 100 nCi/g level. These wastes that do not have enough detectable TRU activity to be classified as TRU waste and have TRU MDAs > 100nCi/g enter a radioactive waste characterization indeterminate state that prevents their dispositioning as either TRU waste or LLW. Spectral summing allows an experienced gamma spectroscopy analyst to add the HENC gamma spectra of a number of similar waste items together to form a consolidated (summed) spectrum. This summed spectrum contains the assay results of the group of items rather than the individual item, and gamma peaks that were not discemable in the individual spectra become quantifiable in the summed spectrum and the MDA for the group sum is reduced. The group of

  15. Application of spectral summing to indeterminate suspect low-level drums at Los Alamos National Laboratory

    SciTech Connect

    Gruetzmacher, Kathleen M; Veilleux, John M; Lucero, Randy P; Seamans, Jr., James V; Clapham, Martin J

    2010-11-09

    An analytical technique developed by Pajarito Scientific Corporation (PSC), utilizing spectral summing of spectra from groups of drums of similar waste type, is being employed by the Waste Disposition Project - Low Level Waste Disposal (WDP-LLWD) Group at Los Alamos National Laboratory (LANL). This technique has been used to disposition low-level radioactive waste that has dropped out of the transuranic (TRU) category and has no place to go unless it can be proven to be LLW and not TRU. The TRU program at LANL run by Mobile Characterization Services (MCS) employs two High Efficiency Neutron Counters (HENC) with built-in gamma assay systems to assay radioactive waste for shipment and disposal as TRU waste at the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico. As well as being certified for WIPP assays, the HENC systems can also be used for low-level waste assays for disposal at LANL or off-site disposal facilities, such as the Nevada Test Site (NTS). Some of the waste processed through the HENC systems cannot be confinned TRU due to the absence of detected TRU alpha emitters above the TRU cutoff of 100 nCi/g. This waste becomes suspect low-level waste (SLLW). In many cases, the waste also can't be classified as LLW because the minimum detectable activity (MDA) of TRU radio nuclides is above the 100 nCi/g level. These wastes that do not have enough detectable TRU activity to be classified as TRU waste and have too high a MDA to be classified as LLW enter a radioactive waste characterization indetenninate status that prevents their dispositioning as either TRU waste or LLW. Spectral summing allows an experienced ganuna spectroscopy analyst to add the HENC gamma spectra of a number of similar waste items together to form a consolidated (summed) spectrum. This summed spectrum contains the assay results of the group of items rather than the individual item, and gamma peaks that were not discernable in the individual spectra can become quantifiable in the

  16. Measurement and interpretation of current transmission in a crossed-field diode below cutoff

    SciTech Connect

    Vanderberg, B.H.; Eninger, J.E.

    1997-02-01

    Measurements on the current-voltage-magnetic field characteristics of a space-charge-limited cylindrical cross-field diode below cutoff are presented. The measured current is found to be lower than predicted by simple cold-fluid theory. This reduction combined with observed oscillations in the current can be explained by secondary electron emission from the anode, leading to an increase of space charge in the diode. {copyright} {ital 1997 American Institute of Physics.}

  17. Induced electric currents in the Alaska oil pipeline measured by gradient, fluxgate, and SQUID magnetometers

    NASA Technical Reports Server (NTRS)

    Campbell, W. H.; Zimmerman, J. E.

    1979-01-01

    The field gradient method for observing the electric currents in the Alaska pipeline provided consistent values for both the fluxgate and SQUID method of observation. These currents were linearly related to the regularly measured electric and magnetic field changes. Determinations of pipeline current were consistent with values obtained by a direct connection, current shunt technique at a pipeline site about 9.6 km away. The gradient method has the distinct advantage of portability and buried- pipe capability. Field gradients due to the pipe magnetization, geological features, or ionospheric source currents do not seem to contribute a measurable error to such pipe current determination. The SQUID gradiometer is inherently sensitive enough to detect very small currents in a linear conductor at 10 meters, or conversely, to detect small currents of one amphere or more at relatively great distances. It is fairly straightforward to achieve imbalance less than one part in ten thousand, and with extreme care, one part in one million or better.

  18. Development of a low-level radon reference atmosphere.

    PubMed

    Linzmaier, Diana; Röttger, Annette

    2013-11-01

    In order to calibrate measurement devices for the activity concentration of Rn-222 (radon) in air below 1,000 Bq/m(3), a constant for long time (>5d), homogeneous reference atmosphere is created by a certified activity in a certified volume. The PTB developed this reference atmosphere from 150 Bq/m(3) to 2,000 Bq/m(3) based on the precisely known emanation of Rn-222 from a Ra-226 activity standard. This set-up reduces uncertainties and increases the range of traceability for commercial radon measurement devices. Thus, a gap in radon metrology is closed. The new primary standard for reference atmospheres is realised with a combined relative standard uncertainty of 1.1%.

  19. Current Measures on Radioactive Contamination in Japan: A Policy Situation Analysis

    PubMed Central

    Gilmour, Stuart; Miyagawa, Shoji; Kasuga, Fumiko; Shibuya, Kenji

    2016-01-01

    were released for areas at risk of radioactive contamination. Monitoring of radioactive materials in food products in the prefectures has been mainly conducted before shipment to restrict the distribution of radio-contaminated foods. Between March 2011 and March 2012, 133,832 tests of non-commercial and commercial products were conducted, and 1,204 tests (0.9%) were found to violate the provisional standards. Since April 2012, 278,275 tests were conducted, and 2,372 tests (0.9%) were found to violate the revised standards. MHLW assessment of representative market baskets of foodstuffs at 15 locations throughout Japan between February and March 2014 found very low estimated dietary intake of radioactive cesium (0.0007–0.019 mSv/year), as did assessments of the contents of an average day’s food. Monitoring of fisheries products in coastal areas affected by the nuclear accident found very limited and declining radio-contamination of live fish outside of Fukushima prefecture. Fisheries monitoring is of limited geographical scope and covers only certain fishes. Conclusions Area-specific bans on production and distribution have been effective in preventing radioactive contamination in the Japanese food market. Currently there is no major concern about radioactive cesium concentrations in retail foodstuffs in Japan, and very low levels of contamination at the production and wholesale stage. However, because the residue limits and food safety policies were revised on an ad hoc, emergency basis after the nuclear accident, the monitoring procedure needs to be reviewed based on objective and scientifically rational criteria. A transparent and objective scientific framework is needed for prioritizing foodstuffs for inspection and revising Prefecture-specific restrictions. Monitoring of fishes and other seafood products in the wild should be regularized and the information made more publicly accessible, and monitoring activities expanded to identify foodstuffs that are no

  20. Greater-than-Class C low-level radioactive waste shipping package/container identification and requirements study. National Low-Level Waste Management Program

    SciTech Connect

    Tyacke, M.

    1993-08-01

    This report identifies a variety of shipping packages (also referred to as casks) and waste containers currently available or being developed that could be used for greater-than-Class C (GTCC) low-level waste (LLW). Since GTCC LLW varies greatly in size, shape, and activity levels, the casks and waste containers that could be used range in size from small, to accommodate a single sealed radiation source, to very large-capacity casks/canisters used to transport or dry-store highly radioactive spent fuel. In some cases, the waste containers may serve directly as shipping packages, while in other cases, the containers would need to be placed in a transport cask. For the purpose of this report, it is assumed that the generator is responsible for transporting the waste to a Department of Energy (DOE) storage, treatment, or disposal facility. Unless DOE establishes specific acceptance criteria, the receiving facility would need the capability to accept any of the casks and waste containers identified in this report. In identifying potential casks and waste containers, no consideration was given to their adequacy relative to handling, storage, treatment, and disposal. Those considerations must be addressed separately as the capabilities of the receiving facility and the handling requirements and operations are better understood.