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Sample records for 36cl production rate

  1. Atmospheric production rate of {sup 36}Cl

    Parrat, Y.; Hajdas, W.; Baltensperger, U.; Synal, H.A.; Kubik, P.W.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Using experimental cross sections, a new calculation of the atmospheric production rate of {sup 36}Cl was carried out. A mean production rate of 20 atoms m{sup -2}s{sup -1} was obtained, which is lower than mean {sup 36}Cl deposition rates. (author) 2 figs., 7 refs.

  2. Determination of 36Cl Production Rates Derived from the Well-Dated Deglaciation Surfaces of Whidbey and Fidalgo Islands, Washington

    Swanson, Terry W.; Caffee, Marc L.

    2001-11-01

    The 36Cl dating method is increasingly being used to determine the surface-exposure history of Quaternary landforms. Production rates for the 36Cl isotopic system, a critical component of the dating method, have now been refined using the well-constrained radiocarbon-based deglaciation history of Whidbey and Fidalgo Islands, Washington. The calculated total production rates due to calcium and potassium are 91±5 atoms 36Cl (g Ca) -1 yr -1 and are 228±18 atoms 36Cl (g K) -1 yr -1, respectively. The calculated ground-level secondary neutron production rate in air, P f(0), inferred from thermal neutron absorption by 35Cl is 762±28 neutrons (g air) -1 yr -1 for samples with low water content (1-2 wt.%). Neutron absorption by serpentinized harzburgite samples of the same exposure age, having higher water content (8-12 wt.%), is ˜40% greater relative to that for dry samples. These data suggest that existing models do not adequately describe thermalization and capture of neutrons for hydrous rock samples. Calculated 36Cl ages of samples collected from the surfaces of a well-dated dacite flow (10,600-12,800 cal yr B.P.) and three disparate deglaciated localities are consistent with close limiting calibrated 14C ages, thereby supporting the validity of our 36Cl production rates integrated over the last ˜15,500 cal yr between latitudes of 46.5° and 51°N. Although our production rates are internally consistent and yield reasonable exposure ages for other localities, there nevertheless are significant differences between these production rates and those of other investigators.

  3. Measurements of 36Cl production rates from Cl, K, and Ca in concrete at the 500-MeV neutron irradiation facility of KENS

    In high-energy accelerator facilities, concrete components around beam lines are exposed to secondary neutrons having various energies during machine operation. The neutrons produce the various long half-life radionuclides, such as 3H, 36Cl, 60Co, and 152Eu, in the concrete. Most of the nuclides mainly produced by thermal neutron-capture reactions and their specific activities are important from the viewpoint of accelerator clearance. In previous work, the specific activities of the 36Cl in the concretes at the various accelerator facilities have been measured and it was suggested that the 36Cl in the concrete is useful as an indicator for thermal neutron fluence because of a characteristic of very long half life (301 kyr). However, in the concretes of the accelerator facilities over several hundreds of MeV, the 36Cl are considerably produced by spallation from other concrete components, such as K and Ca, in addition to the thermal neutron capture of 35Cl. The contribution of the 36Cl productions from the spallation is unclear due to the lack of the cross sections for the neutron-induced reactions. In this work, therefore, we measured the 36Cl production rates in concrete from Cl, K, and Ca targets in irradiation with secondary neutrons, which were produced by a bombardment of primary 500-MeV protons with W targets, at high-energy neutron-irradiation course of KENS. Samples of NaCl, K2CO3, and CaCO3 were set into 7. irradiation spaces located on the depth raging from O to 320 cm from the concrete surface and irradiated for approximately one week. After the irradiation, separations of Cl from the samples were carried out radiochemically and the production rates of 36Cl were determined by the AMS. The production rates from Cl, K, and Ca exponentially decreased with an increase of the depth from the concrete surface, and the profiles were very similar each other. Although the production rates from Cl were two orders higher than those from Ca in the same depth, it is

  4. Calibration of cosmogenic noble gas production in ordinary chondrites based on 36Cl-36Ar ages. Part 1: Refined produced rates for cosmogenic 21Ne and 38Ar

    Dalcher, N.; Caffee, M. W.; Nishiizumi, K.; Welten, K. C.; Vogel, N.; Wieler, R.; Leya, I.

    2013-10-01

    We measured the concentrations and isotopic compositions of He, Ne, and Ar in bulk samples and metal separates of 14 ordinary chondrite falls with long exposure ages and high metamorphic grades. In addition, we measured concentrations of the cosmogenic radionuclides 10Be, 26Al, and 36Cl in metal separates and in the nonmagnetic fractions of the selected meteorites. Using cosmogenic 36Cl and 36Ar measured in the metal separates, we determined 36Cl-36Ar cosmic-ray exposure (CRE) ages, which are shielding-independent and therefore particularly reliable. Using the cosmogenic noble gases and radionuclides, we are able to decipher the CRE history for the studied objects. Based on the correlation 3He/21Ne versus 22Ne/21Ne, we demonstrate that, among the meteorites studied, only one suffered significant diffusive losses (about 35%). The data confirm that the linear correlation 3He/21Ne versus 22Ne/21Ne breaks down at high shielding. Using 36Cl-36Ar exposure ages and measured noble gas concentrations, we determine 21Ne and 38Ar production rates as a function of 22Ne/21Ne. The new data agree with recent model calculations for the relationship between 21Ne and 38Ar production rates and the 22Ne/21Ne ratio, which does not always provide unique shielding information. Based on the model calculations, we determine a new correlation line for 21Ne and 38Ar production rates as a function of the shielding indicator 22Ne/21Ne for H, L, and LL chondrites with preatmospheric radii less than about 65 cm. We also calculated the 10Be/21Ne and 26Al/21Ne production rate ratios for the investigated samples, which show good agreement with recent model calculations.

  5. 36Cl deposition rate reconstruction from bomb pulse until present: A study based on groundwater records

    classically attributed to biological and atmospherical recycling processes or underestimation of the natural atmospheric production of the 36Cl. Additional source of 36Cl production has been envisaged through the activation of chlorine radicals from stratospherical CFCs, leading to a 36Cl production rate comparable with that of Ar spallation from the first approximation. Lastly, the latitudinal factor of the attenuation of the fallout rate is discussed and the impact of the jet streams is proposed as an explanation for the discrepancies in the attenuation rate

  6. Importance of the in situ production of 36Cl, 36Ar and 14C in hydrology and hydrogeochemistry

    The paper critically discusses the conditions for the in situ production of 36Cl, 36Ar and 14C. For several confined aquifers in Australia, Canada and North Africa, the 36Cl content (in atoms/L) close to recharge is about one hundred times greater than can be accounted for by reasonable evapotranspiration values. Possible additional sources of 36Cl include cosmic ray irradiation in the shallow unsaturated zone and solutions of rock chloride in environments where the in situ production of 36Cl is large. Dating of old groundwaters with 36Cl should be limited to cases where chlorinity is constant. The age of Cl-, and hence of groundwater, may then be deduced from the decay of the cosmic 36Cl input, or where the groundwater migrates into a U/Th rich environment, from the subsequent ingrowth of 36Cl because of irradiation by the high in situ neutron flux. In the case of 36Ar, after about 1.5 Ma, the accumulation rate of 36Cl is equal to the 36Cl production rate. In the uppermost few metres of continental crust and of the ocean, cosmic ray interactions enhance production by up to several orders of magnitude. Oceanic production amounts to about one-half of the total production. For Cl- rich fluid inclusions in minerals which remained exposed for a long time close to the surface, values of the 36Ar/40Ar ratio may become much higher than the atmospheric value (3.385x10-3). For 14C, in situ production reactions in both the fluid and the rock matrix and the extent to which they may interfere with the use of 14C for groundwater dating have been assessed. The reactions considered include neutron interactions, the exotic decay of radium and α particle reactions. Groundwater of very low alkalinity in high neutron flux environments (e.g. Stripa granite in central Sweden) may gain in situ produced 14C which is equivalent to a few per cent modern carbon. (author). 57 refs, 4 figs, 3 tabs

  7. Determination and systematics of excitation functions for the production of {sup 36}Cl by means of AMS

    Sudbrock, F.; Herpers, U. [Koeln Univ. (Germany); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Gloris, M.; Michel, R. [Hannover Univ. (Germany)

    1997-09-01

    Studies concerning the production of the long-lived radionuclides {sup 10}Be, {sup 26}Al and {sup 36}Cl measured via accelerator mass spectrometry have been continued. Recently measured data on the production of {sup 36}Cl by medium and high energy protons are discussed. (author) 1 figs., 4 refs.

  8. Estimation of thermal neutron fluences in the concrete of proton accelerator facilities from 36Cl production

    Bessho, K.; Matsumura, H.; Miura, T.; Wang, Q.; Masumoto, K.; Hagura, H.; Nagashima, Y.; Seki, R.; Takahashi, T.; Sasa, K.; Sueki, K.; Matsuhiro, T.; Tosaki, Y.

    2007-06-01

    The thermal neutron fluence that poured into the shielding concrete of proton accelerator facilities was estimated from the in situ production of 36Cl. The thermal neutron fluences at concrete surfaces during 10-30 years of operation were in the range of 1012-1014 n/cm2. The maxima in thermal neutron fluences were observed at ≈5-15 cm in the depths analyzed for 36Cl/35Cl by AMS. These characteristics imply that thermalization of neutrons occurred inside the concrete. Compared to the several tens of MeV cyclotrons, secondary neutrons penetrate deeper into the concrete at the high-energy accelerators possessing acceleration energies of 400 MeV and 12 GeV. The attenuation length of neutrons reflects the energy spectra of secondary neutrons emitted by the nuclear reaction at the beam-loss points. Increasing the energy of secondary neutrons shifts the maximum in the thermal neutron fluences to deeper positions. The data obtained in this study will be useful for the radioactive waste management at accelerator facilities.

  9. Estimation of thermal neutron fluences in the concrete of proton accelerator facilities from 36Cl production

    The thermal neutron fluence that poured into the shielding concrete of proton accelerator facilities was estimated from the in situ production of 36Cl. The thermal neutron fluences at concrete surfaces during 10-30 years of operation were in the range of 1012-1014 n/cm2. The maxima in thermal neutron fluences were observed at ∼5-15 cm in the depths analyzed for 36Cl/35Cl by AMS. These characteristics imply that thermalization of neutrons occurred inside the concrete. Compared to the several tens of MeV cyclotrons, secondary neutrons penetrate deeper into the concrete at the high-energy accelerators possessing acceleration energies of 400 MeV and 12 GeV. The attenuation length of neutrons reflects the energy spectra of secondary neutrons emitted by the nuclear reaction at the beam-loss points. Increasing the energy of secondary neutrons shifts the maximum in the thermal neutron fluences to deeper positions. The data obtained in this study will be useful for the radioactive waste management at accelerator facilities

  10. The Hiroshima thermal-neutron discrepancy for (36)Cl at large distances. Part II: Natural in situ production as a source.

    Nolte, Eckehart; Huber, Thomas; Rühm, Werner; Kato, Kazuo; Lazarev, Vitali; Schultz, Ludolf

    2005-10-01

    For Hiroshima, a large discrepancy between calculated and measured thermal-neutron fluences had been reported in the past, for distances to the epicenter larger than about 1,000 m. To be more specific, measured (36)Cl concentrations in environmental samples from Hiroshima were too large at these distances, and the ratio of measured to calculated values reached about 70, at a distance of 1,800 m. In an attempt to identify other sources that might also produce (36)Cl in Hiroshima samples, the role of cosmic rays and of neutrons from natural terrestrial sources was investigated. Four reaction mechanisms were taken into account: spallation reactions of the nucleonic (hadronic) component of the cosmic rays on potassium (K) and calcium (Ca) in the sample material, particle emission after nuclear capture of negative muons by K and Ca, reactions of fast-muon induced electromagnetic, and hadronic showers with K and Ca, and neutron capture reactions with (35)Cl in the sample where the neutrons originate from the above three reaction mechanisms and from uranium and thorium decay. These mechanisms are physically described and mathematically quantified. It is shown that among those parameters important for the production of (36)Cl in granite, the chemical composition of the sample, the depth in the quarry where the sample had initially been taken, and the erosion rate at the site of the quarry are most important. Based on these physical, chemical, and geological parameters, (36)Cl concentrations were calculated for different types of granite that are typical for the Hiroshima area. In samples that were of these granite types and that had not been exposed to atomic bomb(A-bomb) neutrons, the (36)Cl concentration was also determined experimentally by means of accelerator mass spectrometry, and good agreement was found with the calculated values. The (36)Cl signal due to natural in situ production was also calculated in granite samples that had been exposed to A-bomb neutrons at

  11. Measurement of the 36Cl deposition flux in central Japan: natural background levels and seasonal variability

    Essential parameters for the applications of 36Cl as a tracer in groundwater studies include the initial 36Cl/Cl ratio, at the time of recharge, and/or the natural background deposition flux of 36Cl in the recharge area. To facilitate the hydrological use of 36Cl in central Japan, this study aimed to obtain a precise estimate of the long-term average local 36Cl flux and to characterize its seasonal variability. The 36Cl in precipitation was continuously monitored in Tsukuba, central Japan over a period of >5 years. The 36Cl flux showed a clear seasonal variation with an annual peak during the spring, which was attributed to the seasonal variability of tropopause height. The long-term average 36Cl flux (32 ± 2 atoms m−2 s−1), estimated from the measured data, was consistent with the prediction from the 36Cl latitudinal fallout model scaled using the global mean production rate of 20 atoms m−2 s−1. The initial 36Cl/Cl ratio was estimated to be (41 ± 6) × 10−15, which is similar to that of pre-bomb groundwater in the Tsukuba Upland. An observation period covering an 11-year solar cycle would yield more accurate estimates of the values, given the increased 36Cl flux during the solar minimum. - Highlights: ► We monitored 36Cl in precipitation in central Japan over a period of >5 years. ► The 36Cl flux varied seasonally, with a peak in spring. ► The long-term average 36Cl flux and the initial 36Cl/Cl ratio were 32 ± 2 atoms m−2 s−1 and (41 ± 6) × 10−15, respectively. ► An observation period covering an 11-year solar cycle would yield more accurate estimates of the values, given the increased 36Cl flux during the solar minimum.

  12. Estimation of precipitation rates by measurements of {sup 36}Cl in the GRIP ice core with the PSI/ETH tandem accelerator

    Wagner, G.; Baumgartner, S.; Beer, J. [EAWAG, Duebendorf (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Within the European Greenland ice core project (GRIP) {sup 36}Cl AMS measurements have been performed on ice core samples from Summit (Greenland, 73{sup o}N, 37{sup o}W). Most data analysed so far are from the lower part of the ice core. The {sup 36}Cl concentration is well correlated with {delta}{sup 18}O, which is considered as a proxy for paleotemperatures. Assuming that the deposition rate of radionuclides is independent of {delta}{sup 18}O, {sup 36}Cl is used to estimate the relationship between accumulation and {delta}{sup 18}O. The results confirm that the rapid changes of {delta}{sup 18}O, the so-called Dansgaard-Oeschger events, are also reflected in the precipitation rate. (author) 1 fig., 3 refs.

  13. Cosmogenic radionuclides in the environment: 32Si in precipitation samples from the Jungfraujoch, production cross sections of 36Cl in Argon and modeling of the atmospheric 36Cl production

    The concentrations of the cosmogenic radionuclide 32Si were measured in four fresh snow samples from the Jungfraujoch in the Swiss Alps (3450 m asl.) to study the feasibility of measuring this potential dating nuclide with Accelerator Mass Spectrometry. This technique could reduce drastically the amount of material needed for measurements of 32Si concentrations in environmental samples in contrast to conventional radiometric detection. The measured 32Si concentrations in the snow samples were between 1.84 and 6.28 μBql-1. These values agree with other measurements of precipitation samples. The measured 32Si/Sitot ratios ranged from 2.5.10-17 to 2.3.10-15 and were thus below the present detection limit of about 10-14, showing that at present it is not possible to carry out AMS measurements of 32Si in precipitation samples. For the first time, experimental cross sections of the reaction 40Ar(p,X)36Cl have been determined for the proton energy range 16-590 MeV. These cross sections were measured using a gas target, a novel method which was tested successfully by irradiating nitrogen targets to confirm literature values of the N(p,X)7Be and N(p,X)10Be cross sections. In fact, good agreement was found between the obtained cross sections with those using solid targets. Production of several radionuclides in the reaction of proton with nickel were also measured. Comparison of these cross sections with literature data proved that the proton flux measurements carried out with ionization chambers were very accurate. The excitation function of the reaction 40Ar(p,X)36Cl exhibits two maxima at proton energies of 20 MeV for the (p,αn)reaction and 95 MeV for the (p,2p3n) reaction, with maximum cross sections of 105 mb and 53 mb, respectively. (author) figs., tabs., refs

  14. First experimental results of the 33S(α,p)36Cl cross section for production in the Early Solar System

    Short-lived radionuclides (SLRs), with t1/2 36Cl (t1/2 = 3.01 × 105 a) has been determined from correlation between isotopic enrichment of its daughter isotope, 36S, and Cl abundance in meteorites. The relatively high inferred initial Solar System 36Cl/Cl ratio strongly suggests that 36Cl was produced in the ESS by bombardment of solar energetic particles on gas and dust in the protoplanetary disc. A major uncertainty in the irradiation models is the absence of experimental data. Experimental data on key 36Cl production reactions will help constrain the calculated yields. Of the reactions considered in the ESS models, the 33S(α,p)36Cl reaction is one of the most important. Here we report first results of a measurement of the averaged reaction cross section in the energy range 1.84–2.04 MeV/A. Our result, 192 ± 33 mb (1σ), is significantly higher than results of previous calculations, 102 and 34 mb.

  15. APMP comparison of measurement of surface emission rate of 36Cl large area source (APMP.RI(II)-K2.Cl-36)

    An international comparison of measurement of beta particle surface emission rate from a 36Cl large area source (APMP.RI(II)–S1.Cl-36) was carried out within the framework of the Asia-Pacific Metrology Program (APMP). Participants from APMP were NMIJ (Japan), KRISS (Korea) and INER (Chinese Taipei). Participants from the other RMOs were NIST (United States), PTB (Germany), NMISA (South Africa) and VNIIM (Russia). All the results of the participants agreed within ±1%. This was the first international comparison of measurement of surface emission rate of beta particle from a large area source. - Highlights: ► APMP comparison of measurement of beta particle surface emission rate was reported. ► Participants were NMIJ, KRISS, INER, NIST, PTB, NMISA and VNIIM. ► A 36Cl large area source was used in the comparison. ► All the results of the participants agreed within ±1%.

  16. Production of cosmogenic isotopes 7Be, 10Be, 14C, 22Na and 36Cl in the atmosphere: Altitudinal profiles of yield functions

    Poluianov, Stepan; Mishev, Alexander L; Usoskin, Ilya G

    2016-01-01

    New consistent and precise computations of the production of five cosmogenic radio-isotopes, 7Be, 10Be, 14C, 22Na and 36Cl, in the Earth's atmosphere by cosmic rays are presented in the form of tabulated yield functions. For the first time, a detailed set of the the altitude profiles of the production functions is provided which makes it possible to apply the results directly as input for atmospheric transport models. Good agreement with most of the earlier published works for columnar and global isotopic production rates is shown. Altitude profiles of the production are important, in particular for such tasks as studies of strong solar particle events in the past, precise reconstructions of solar activity on long-term scale, tracing air-mass dynamics using cosmogenic radio-isotopes, etc. As an example, computations of the $^{10}$Be deposition flux in the polar region are shown for the last decades and also for a period around 780 AD and confronted with the actual measurements in Greenland and Antarctic ice c...

  17. Slip rate variability over the Holocene period in the middle Aterno fault system (Italy), retrieved from in situ 36Cl cosmogenic nuclide dating of exhumed fault-plane.

    Tesson, Jim; Benedetti, Lucilla; Pucci, Stefano; Villani, Fabio; Bourles, Didier; Keddadouche, Karim; Aumaitre, Georges

    2016-04-01

    Numerous numerical modeling studies have described and quantified non-stochastic spatio-temporal variations of earthquake occurrences within fault-networks, such as temporal clustered earthquakes or fault synchronization. However, very few long-enough paleoseismological and geological records are available to test those models against well-constrained dataset and thus account for such variability in the fault behavior. The prerequisites for improving our understanding of fault-rupture processes and thus our capacity to better assess seismic hazard are to acquire paleoseismological records that enable to derive both long-term slip-rate and short-term variability, on a large population of faults and/or within a fault system. These conditions met in Central Apennines, an extensional province where substantial paleoseismological dataset accurately described the Holocene seismic history of a dense network of normal faults. In this study we use 36Cl in situ cosmogenic nuclide to retrieve the seismic history of 3 faults belonging to the Middle Aterno fault system, from north to south: the Bazzano fault, the Roccapreturo fault and the Sulmona fault, a portion of which ruptured during the 2009 L'Aquila earthquake in Italy. We use a new modeling approach to determine the age and slip of past seismic events from the 36Cl concentration profiles. This model is based on an inverse approach and uses an optimization algorithm enabling all the parameter space (number of events, age and slip of events, pre-exposure) to be explored without a priori constraints (see Tesson et al. in session TS4.2/NH4.16/SM3.8). Using this new approach, we precisely determine the slip events occurrences over the Holocene period of those three faults. The results indicate that the three studied faults have ruptured between 4.5 and 5.5 ka, while the southernmost part of the system has also ruptured between at 1.5-3 ka (Sulmona fault and southern segment of Roccapreturo). Those results are in agreement

  18. 36Cl bomb peak: comparison of modeled and measured data

    A. Eichler

    2009-06-01

    Full Text Available The extensive nuclear bomb testing of the fifties and sixties and the final tests in the seventies caused a strong 36Cl peak that has been observed in ice cores world-wide. The measured 36Cl deposition fluxes in eight ice cores (Dye3, Fiescherhorn, Grenzgletscher, Guliya, Huascarán, North GRIP, Inylchek (Tien Shan and Berkner Island were compared with an ECHAM5-HAM general circulation model simulation (1952–1972. We find a good agreement between the measured and the modeled 36Cl fluxes assuming that the bomb test produced global 36Cl input was ~80 kg. The model simulation indicates that the fallout of the bomb test produced 36Cl is largest in the subtropics and mid-latitudes due to the strong stratosphere-troposphere exchange. In Greenland the 36Cl bomb signal is quite large due to the relatively high precipitation rate. In Antarctica the 36Cl bomb peak is small but is visible even in the driest areas. The model suggests that the large bomb tests in the Northern Hemisphere are visible around the globe but the later (end of sixties and early seventies smaller tests in the Southern Hemisphere are much less visible in the Northern Hemisphere. The question of how rapidly and to what extent the bomb produced 36Cl is mixed between the hemispheres depends on the season of the bomb test. The model results give an estimate of the amplitude of the bomb peak around the globe.

  19. 36Cl bomb peak: comparison of modeled and measured data

    A. Eichler

    2009-01-01

    Full Text Available The extensive nuclear bomb testing of the fifties and sixties and the final tests in the seventies caused a strong 36Cl peak that has been observed in ice cores world-wide. The measured 36Cl deposition fluxes in eight ice cores (Dye3, Fiescherhorn, Grenzgletscher, Guliya, Huascarán, North GRIP, Inylchek (Tien Shan and Berkner Island were compared with an ECHAM5-HAM general circulation model simulation (1952–1972. We find a good agreement between the measured and the modeled 36Cl fluxes assuming that the bomb test produced global 36Cl input was ~80 kg. The model simulation indicates that the fallout of the bomb test produced 36Cl is largest in the subtropics and mid-latitudes due to the strong stratosphere-troposphere exchange. In Greenland the 36Cl bomb signal is quite large due to the relatively high precipitation rate. In Antarctica the 36Cl bomb peak is small but is visible even in the driest areas. The model suggests that the large bomb tests in the Northern Hemisphere are visible around the globe but the later (end of sixties and early seventies smaller tests in the Southern Hemisphere are much less visible in the Northern Hemisphere. The question of how rapidly and to what extent the bomb produced 36Cl is mixed between the hemispheres depends on the season of the bomb test. The model results give an estimate of the amplitude of the bomb peak around the globe.

  20. EFFECT OF DOSE ON RESIDUES AND DISPOSITION OF AN EXPERIMENTAL 36CL-CHLORATE PRODUCT IN BROILERS.

    Because pathogenic Salmonella species and E. coli O157:H7 have significant impacts on human health and on the food animal industry, pre-harvest intervention techniques are being pursued to control these bacteria in food animals. An experimental sodium chlorate product (ECP) consistently reduces or e...

  1. Influence of ground level enhancements on the terrestrial production of {sup 10}Be, {sup 14}C and {sup 36}Cl

    Herbst, Konstantin; Heber, Bernd [IEAP, Christian-Albrechts-Universitaet zu Kiel, Kiel (Germany); Beer, Juerg [Swiss Federal Institute of Aquatic Science and Technology, EAWAG (Switzerland); Tylka, Allan J. [Space Science Division, Naval Research Laboratory, Washington, DC (United States); Dietrich, William F. [Praxis, Inc., Alexandria, VA (United States)

    2014-07-01

    Cosmogenic radionuclides are a product of the interaction of primary cosmic rays, in particular galactic cosmic rays (GCRs), with the Earth's atmosphere. But only primary particles with energies above several 100 MeV can trigger the necessary reaction chains. Because GCRs are modulated by the solar activity on their way through the interplanetary medium the GCR-induced cosmogenic radionuclide production is anti-correlated to the solar cycle. During phases of strong solar activity also solar energetic particle (SEP) events occur frequently. In particular SEP events which can be detected by ground-based instruments, so-called ground level enhancements (GLEs), may strongly contribute to the cosmogenic radionuclide production. Beside the variation due to the modulation of GCRs we investigate the influence of 58 GLEs, which occurred within the past five solar cycles and discuss the possibility to detect such events in present ice-core and tree-ring records. In addition, an estimate for the probability to find such events over the past 10'000 years, also known as Holocene, during different modulation conditions are given.

  2. Cosmogenic 36Cl in karst waters from Bunker Cave North Western Germany - A tool to derive local evapotranspiration?

    Münsterer, C.; Fohlmeister, J.; Christl, M.; Schröder-Ritzrau, A.; Alfimov, V.; Ivy-Ochs, S.; Wackerbarth, A.; Mangini, A.

    2012-06-01

    Monthly rain and drip waters were collected over a period of 10 months at Bunker Cave, Germany. The concentration of 36Cl and the 36Cl/Cl-ratios were determined by accelerator mass spectrometry (AMS), while stable (35+37)Cl concentrations were measured with both, ion chromatography (IC) and AMS. The measured 36Cl-fluxes of (0.97 ± 0.57) × 104 atoms cm-2 month-1 (0.97 atoms m-2 month-1) in precipitation were on average twice as high as the global mean atmospheric production rate. This observation is consistent with the local fallout pattern, which is characterized by a maximum at mid-latitudes. The stable chloride concentration in drip waters (ranging from 13.2 to 20.9 mg/l) and the 36Cl-concentrations (ranging from 16.9 × 106 to 35.3 × 106 atoms/l) are a factor of 7 and 10 above the values expected from empirical evapotranspiration formulas and the rain water concentrations, respectively. Most likely the additional stable Cl is due to human impact from a nearby urban conglomeration. The large 36Cl-enrichment is attributed to the local evapotranspiration effect, which appears to be higher than the calculated values and to additional bomb-derived 36Cl from nuclear weapons tests in the 1950s and 60s stored in the soil above the cave. In the densely vegetated soil above Bunker Cave, 36Cl seems not to behave as a completely conservative tracer. The bomb derived 36Cl might be retained in the soil due to uptake by minerals and organic material and is still being released now. Based on our data, the residence time of 36Cl in the soil is estimated to be about 75-85 years.

  3. Temporal evolution of 36Cl abundances in the Great Lakes

    The observed 36Cl isotopic abundance in Great Lakes water decreases from west to east, with the highest 36Cl/Cl ratio of 1332 × 10−15 in Lake Superior and the lowest 36Cl/Cl ratio of 151 × 10−15 in Lake Erie, whereas the 36Cl concentration (36Cl atoms/L) is lowest in Lake Superior and higher in the other Great Lakes. The 36Cl concentration in Lake Superior is much higher than expected from normal atmospheric deposition over the basin, consistent with deposition of nuclear bomb-produced 36Cl during 1952–1964. A conservative mass-balance model constrained by hydrological parameters and available 36Cl fluence measurements predicts the 36Cl abundances in the Great Lakes from 1945 to 2015, in excellent agreement with available data for Lakes Superior, Michigan, and Huron, but the model underestimates 36Cl abundances for Lakes Erie and Ontario. However, assuming that 36Cl demonstrates non-conservative behavior and is significantly retained in the drainage basins, a model incorporating a delayed input parameter successfully predicts observed 36Cl concentrations in all of the Great Lakes. - Highlights: • 36Cl/Cl ratios are the highest in Lake Superior and the lowest in Lake Erie. • 36Cl concentrations in the Great Lakes are much higher than expected natural values. • Conservative 36Cl model underestimates observed values in Lakes Erie and Ontario. • Large fraction of 36Cl atoms deposited on the watersheds are retained for decades

  4. Studies on methods of measurement of radioactivities of 36Cl and 3H in dual labelled samples

    In order to clarify how chloride molecules are transported into nervous tissue cells, we simultaneously used [36Cl] -NaCl and [3H] -inulin, and added AgNO3 to the extract from the nervous tissue, obtaining 36Cl-samples from the AgCl-precipitate and 3H-samples from the supernatant. As for radioactivity of 36Cl or 3H in the dual-labelled samples, the recovery rates by our separation method were about 100%. Using cultured astrocytoma cells, 36Cl-uptake into the cells, which was calculated by inulin assumption, was investigated. Intracellular 36Cl-radioactivity changed vis-a-vis with that in the extracellular space. The volume of intracellular water, which was calculated by 3H-inulin assumption, remained unchanged, even though a few variations in 36Cl-radioactivity in cells were determined by both our separation method and spill-over method. (author)

  5. A hydrochemical investigation using 36Cl/Cl in groundwaters

    Metcalfe, R.

    2003-01-01

    This report describes 36Cl studies which were undertaken during the H14 financial year. 6 groundwater samples were collected for 36Cl analysis. The results of this study suggest that 36Cl data could potentially be useful for interpreting groundwater origins and flow paths.

  6. 36Cl measurement program at Zuerich 6 MV tandem accelerator

    Routine measurements of 36Cl at Zuerich 6MV tandem accelerator cover a time span of 20 years. In the present contribution, we summarize our practical experience of 36Cl measurements with a special emphasis on the detection procedure and data reduction. We also outline a synopsis of our ongoing and past 36Cl projects

  7. Infiltration at yucca mountain, nevada, traced by 36Cl

    Norris, A. E.; Wolfsberg, K.; Gifford, S. K.; Bentley, H. W.; Elmore, D.

    1987-11-01

    Measurements of chloride and 36Cl in soils from two locations near Yucca Mountain, Nevada, have been used to trace the infiltration of precipitation in this arid region. The results show that the 36Cl fallout from nuclear-weapons testing formed a well-defined peak at one location, with a maximum 36Cl/Cl ratio 0.5 m below the surface. The structure of the 36Cl bomb pulse at the other location was much more complex, and the quantity of 36Cl in the bomb pulse was < 1% of the 6 × 10 12 atoms {36Cl }/{m 2} in the bomb pulse at the first location. The data indicate hydrologic activity subsequent to the 36Cl bomb-pulse fallout at one location, but none at the other location.

  8. AMS measurement of the reaction 35Cl(n,γ)36Cl

    36Cl is a long-lived radionuclide (t1/2=301000 a), which is dominantly produced via the reaction 35Cl(n,γ)36Cl. In the present work we focused on: First, the production of an independent 36Cl/35Cl reference material for AMS and second, the determination of the Maxwellian averaged cross section (MACS) of 35Cl(n,γ)36Cl at 25 keV neutron energy, i.e. the energy range which is important for astrophysical network calculations. Approaching the first goal, NaCl pellets were irradiated with thermal neutrons in Vienna and Budapest. The neutron fluence, used for the calculation of the 36Cl/35Cl ratio of the irradiated samples, was determined via gold fluence monitors. For the determination of the neutron capture cross section of 35Cl at stellar energies, AMS measurements were performed on two samples, which were irradiated with neutrons of a Maxwell-Boltzmann energy distribution of 25 keV. Combining the AMS- and the neutron-fluence data, the MACS for 35Cl at 25 keV was calculated. The neutron irradiations, the measuring procedure of 36Cl at VERA and our new results are presented.

  9. Determination of paleoseismic activity over a large time-scale: Fault scarp dating with 36Cl

    Mozafari Amiri, Nasim; Tikhomirov, Dmitry; Sümer, Ökmen; Özkaymak, Çaǧlar; Uzel, Bora; Ivy-Ochs, Susan; Vockenhuber, Christof; Sözbilir, Hasan; Akçar, Naki

    2016-04-01

    Bedrock fault scarps are the most direct evidence of past earthquakes to reconstruct seismic activity in a large time-scale using cosmogenic 36Cl dating if built in carbonates. For this method, a surface along the fault scarp with a minimum amount of erosion is required to be chosen as an ideal target point. The section of the fault selected for sampling should cover at least two meters of the fault surface from the lower part of the scarp, where intersects with colluvium wedge. Ideally, sampling should be performed on a continuous strip along the direction of the fault slip direction. First, samples of 10 cm high and 15 cm wide are marked on the fault surface. Then, they are collected using cutters, hammer and chisel in a thickness of 3 cm. The main geometrical factors of scarp dip, scarp height, top surface dip and colluvium dip are also measured. Topographic shielding in the sampling spot is important to be estimated as well. Moreover, density of the fault scarp and colluvium are calculated. The physical and chemical preparations are carried in laboratory for AMS and chemical analysis of the samples. A Matlab® code is used for modelling of seismically active periods based on increasing production rate of 36Cl following each rupture, when a buried section of a fault is exposed. Therefore, by measuring the amount of cosmogenic 36Cl versus height, the timing of major ruptures and their offsets are determined. In our study, Manastır, Mugırtepe and Rahmiye faults in Gediz graben, Priene-Sazlı, Kalafat and Yavansu faults in Büyük Menderes graben and Ören fault in Gökava half-graben have been examined in the seismically active region of Western Turkey. Our results reconstruct at least five periods of high seismic activity during the Holocene time, three of which reveal seismic ruptures beyond the historical pre-existing data.

  10. 36Cl studies of water movements deep within unsaturated tuffs

    Measurements of 36Cl in cuttings from a borehole that was drilled 387 m into unsaturated tuffs indicate the possible detection of significant radioactive decay of cosmogenic 36Cl in two of the samples. However, the 36Cl/Cl ratio was found to vary with the amount of pulverization of the cuttings. Work is in progress to separate the 36Cl/Cl data into cosmogenic and in situ components. The cosmogenic component will be used to trace very slow water movements through the unsaturated zone. Bomb pulse 36Cl was observed as deep as 153 m, and this identification is not constrained by the problem with pulverization. This work shows the efficacy of 36Cl measurements for detecting modern water movements deep in the unsaturated zone. 9 refs., 3 tabs

  11. Study of nuclear reactions producing 36Cl by micro-AMS

    Luís, H.; Jesus, A. P.; Fonseca, M.; Cruz, J.; Galaviz, D.; Franco, N.; Alves, E.

    2016-01-01

    36Cl is one of several short to medium lived isotopes (as compared to the earth age) whose abundances at the earlier solar system may help to clarify its formation process. There are two generally accepted possible models for the production of this radionuclide: it originated from the ejecta of a nearby supernova (where 36Cl was most probably produced in the s-process by neutron irradiation of 35Cl) and/or it was produced by in-situ irradiation of nebular dust by energetic particles (mostly, p, a, 3He -X-wind irradiation model). The objective of the present work is to measure the cross section of the 37Cl(p,d)36Cl and 35Cl(d,p)36Cl nuclear reactions, by measuring the 36Cl content of AgCl samples (previously bombarded with high energy protons and deuterons) with AMS, taking advantage of the very low detection limits of this technique for chlorine measurements. For that, the micro-AMS system of the LF1/ITN laboratory had to be optimized for chlorine measurements, as to our knowledge this type of measurements had never been performed in such a system (AMS with micro-beam). Here are presented the first results of these developments, namely the tests in terms of precision and reproducibility that were done by comparing AgCl blanks irradiated at the Portuguese National Reactor with standards produced by the dilution of the NIST SRM 4943 standard material.

  12. 36Cl-AMS measurements with 3-MV tandem accelerator

    36C- is one of the most interesting nuclides in accelerator mass spectrometry (AMS) measurements. The application of 36Cl has been widely applied in various fields. All most all of 36Cl AMS measurements at natural isotopic concentrations have yet been performed at tandem accelerator with 5 MV or higher terminal voltage. The measure improvement of 36Cl and other medium heavy isotopes performed at 3 MV in AMS facilities is one of the hottest topics in AMS measurements. In order to increase the suppression factor of 36S, the energy loss straggling and angular straggling of 36Cl and 36S ions in various counter gases (P10, isobutane and propane) were investigated. Some groundwater samples were measured with energy of 32 MeV, and the results were in good agreement with the result obtained with ion energy of 72 MeV. The results indicate that the approximate detection limit of 36Cl in 3 MV AMS facility is 36Cl/Cl=1 × 10-14, and the uncertainty is 30% when the sample with isotopic ration 36Cl/Cl≈10-13. (authors)

  13. High (36)Cl/Cl ratios in Chernobyl groundwater.

    Roux, Céline; Le Gal La Salle, Corinne; Simonucci, Caroline; Van Meir, Nathalie; Fifield, L Keith; Diez, Olivier; Bassot, Sylvain; Simler, Roland; Bugai, Dmitri; Kashparov, Valery; Lancelot, Joël

    2014-12-01

    After the explosion of the Chernobyl Nuclear Power Plant in April 1986, contaminated material was buried in shallow trenches within the exclusion zone. A (90)Sr plume was evidenced downgradient of one of these trenches, trench T22. Due to its conservative properties, (36)Cl is investigated here as a potential tracer to determine the maximal extent of the contamination plume from the trench in groundwater. (36)Cl/Cl ratios measured in groundwater, trench soil water and leaf leachates are 1-5 orders of magnitude higher than the theoretical natural (36)Cl/Cl ratio. This contamination occurred after the Chernobyl explosion and currently persists. Trench T22 acts as an obvious modern point source of (36)Cl, however other sources have to be involved to explain such contamination. (36)Cl contamination of groundwater can be explained by dilution of trench soil water by uncontaminated water (rainwater or deep groundwater). With a plume extending further than that of (90)Sr, radionuclide which is impacted by retention and decay processes, (36)Cl can be considered as a suitable tracer of contamination from the trench in groundwater provided that modern release processes of (36)Cl from trench soil are better characterized. PMID:25128774

  14. High 36Cl/Cl ratios in Chernobyl groundwater

    After the explosion of the Chernobyl Nuclear Power Plant in April 1986, contaminated material was buried in shallow trenches within the exclusion zone. A 90Sr plume was evidenced downgradient of one of these trenches, trench T22. Due to its conservative properties, 36Cl is investigated here as a potential tracer to determine the maximal extent of the contamination plume from the trench in groundwater. 36Cl/Cl ratios measured in groundwater, trench soil water and leaf leachates are 1–5 orders of magnitude higher than the theoretical natural 36Cl/Cl ratio. This contamination occurred after the Chernobyl explosion and currently persists. Trench T22 acts as an obvious modern point source of 36Cl, however other sources have to be involved to explain such contamination. 36Cl contamination of groundwater can be explained by dilution of trench soil water by uncontaminated water (rainwater or deep groundwater). With a plume extending further than that of 90Sr, radionuclide which is impacted by retention and decay processes, 36Cl can be considered as a suitable tracer of contamination from the trench in groundwater provided that modern release processes of 36Cl from trench soil are better characterized. - Highlights: • High 36Cl/Cl ratios measured in the Chernobyl Pilot Site groundwater. • Trench T22 acts as a modern source of groundwater contamination by 36Cl but other sources are involved. • Contamination results from dilution of a contaminated “T22” soil water with rainwater. • Processes involved in the modern release need to be investigated

  15. Cosmogenic 10Be, 21Ne and 36Cl in sanidine and quartz from Chilean ignimbrites

    Our initial results indicate that three cosmogenic nuclides: 10Be, 21Ne and 36Cl can be analyzed in sanidine. To uncover complex exposure histories or marked changes in denudation rates over time several nuclides with different half-lives (or stable) must be measured. Because of its shorter half-life, the combination of 36Cl and a long-lived nuclide 10Be or stable nuclide 21Ne will provide more information than the pairs 10Be and 26Al or 10Be and 21Ne (in quartz). Sanidine (alkali feldspar) is a common high temperature mineral and often dominates the phenocryst assemblage in silicic to intermediate volcanic rocks. Bedrock surfaces studied come from the Oxaya (erupted 19-23 Ma) and Lauca (erupted 2.7 Ma) ignimbrites of northern Chile. Quartz and sanidine phenocrysts coexist; therefore, we can check the viability of sanidine through direct comparison with nuclide concentrations in quartz. In addition, as quartz has no target for 36Cl in significant abundance we show that the unique power of sanidine is that 36Cl can be measured. We have obtained very good agreement between 10Be and 21Ne concentrations measured in sanidine and coexisting quartz. No meteoric 10Be was apparent in these sanidines. Concentrations of all three nuclides in mineral separates from rock sample CN309 from the Lauca ignimbrite in the Western Cordillera agree well and correspond to minimum exposure ages of 30-50 ka. 10Be and 21Ne measured in both sanidine and quartz from three rock samples from the Oxaya ignimbrite (CN19, CN23, CN104a) in the Western Escarpment record low average landscape modification rates (36Cl data from sanidine in CN23 seem to indicate shorter minimum exposures and more rapid maximum erosion rates

  16. Alligator Rivers Analogue project. Geochemistry of 239Pu, 129I, 99Tc and 36Cl

    One objective of this research programme has been to evaluate the applicability of uranium orebodies as natural analogues for testing radionuclide release-rate models used in performance assessment activities. The investigated nuclides included three of the most persistent radioactive constituents of high-level wastes from nuclear fission power reactors: plutonium-239, iodine-129, and technetium-99. The feasibility of uranium minerals as analogues for the behavior of these nuclear reaction products (NRP) in spent fuel relies upon a capability to characterise NRP concentrations in the source minerals. Measured abundances of natural 239Pu, 99Tc and 129I in uranium ores are compared to calculated abundances in order to evaluate the degree to retention of these radionuclides by the ore. This modelling study also shows the extent to which various NRP are correlated, such that one provides a constraint on the production rates of others. Under most conditions, 36Cl, another long-lived neutron-capture product found in uranium ores, is shown to be an ideal in-situ monitor of the 235U fission rate, which is the dominant source term for 129I and possibly a significant one for 99Tc. Similarly, 239Pu/U ratios can be used to establish limits on the 238U neutron-induced fission rate; the ratios measured in this study suggest that 238U induced fission comprises 129I and 99Tc. 79 refs., 21 tabs., 18 figs

  17. Accelerator-mass spectroscopy with fully stripped 36Cl

    The Garching MP tandem-post accelerator-achromator accelerator facility was extended in such way that by it a very backgroundless accelerator mass spectroscopy with fully stripped medium heavy ions was possible. As first applications microscopical amounts of 36Cl (Tsub(1/2)= 301 000 years) were detected. The detection limit lies at 36Cl/CL=4x10-15. In first measurements the method was applied to the age determination of palaeontological samples and to the study of cosmic-radiation induced reactions in the earth crust. (orig.)

  18. Comparison of 36Cl and 3He measurements in glacial surfaces on the tropical Altiplano (Cerro Tunupa volcano, 20°S)

    Schimmelpfennig, Irene; Blard, Pierre-Henri; Lavé, Jérôme; Benedetti, Lucilla; Aster Team

    2016-04-01

    The combination of two or more cosmogenic nuclides measured in the same rock samples allow complex landscape exposure histories to be quantified, due to the nuclide-specific production and decay rates. In supposedly simple exposure scenarios, such as moraine chronologies, the use of more than one nuclide can also help identify outliers caused by geomorphological bias (e.g. "inheritance") or analytical problems (e.g. nuclide loss or contamination during chemical extraction). The two cosmogenic in situ nuclides 3He and 36Cl are potentially very useful to be simultaneously measured in quartz-lacking lithologies, but their application is more challenging than that of combined 10Be and 26Al measurements, which are routinely employed in quartz-bearing rocks. This is, amongst other things, because the production of 3He and 36Cl depend on various compositional factors. Therefore, 3He and 36Cl have rarely been measured in the same samples so far. Here, we present 36Cl measurements in plagioclases extracted from four moraine boulders and one roche moutonnée on the southern flank of Cerro Tunupa volcano, located in the tropical Bolivian Andes (3800-4500 m, 20°S). In pyroxenes of these samples, 3He has previously been measured to gain insights into the local deglaciation history and climate conditions about 15 kyr ago during the Lake Tauca highstand (Blard et al., 2009, 2013). The ages calculated from the measured 3He and 36Cl concentrations of the 5 samples range from 12 kyr to 180 kyr and are generally in good agreement. The good age agreement of a boulder surface (TU-1C) that is significantly older than the other boulder ages from this moraine confirm the suspicion, that it was exposed to cosmic radiation previous to its last deposition (Blard et al., 2009, 2013). In contrast, the 36Cl age of the roche moutonnée surface (TU2) is significantly younger than the corresponding 3He age, but fits well with the adjacent moraine mean age. It thus arises the question if the 3He

  19. 36Cl and 53Mn in Antarctic meteorites and 10Be-36Cl dating of Antarctic ice

    Cosmic-ray-produced 53Mn (tsub(1/2)=3.7x106 years) has been measured in twenty Antarctic meteorites by neutron activation analysis. 36Cl (tsub(1/2)=3.0x105 years) has been measured in fourteen of these objects by tandem accelerator mass spectrometry. Cosmic ray exposure ages and terrestrial ages of the meteorites are calculated from these results and from gases. 14C (tsub(1/2)=5740 years) and 26Al(tsub(1/2)=7.2x105 years) data. The terrestrial ages range from 3x104 to 5x105 years. Many of the L3-Allan Hills chrondrites seem to be a single fall based on these results. In addition, 10Be (tsub(1/2)=1.6x106 years) and 36Cl have been measured in six Antarctic ice samples. The first measurements of 10Be/36Cl ratios in the ice core samples demonstrate a new dating method for ice. (orig.)

  20. Surface exposure dating with 10Be, 26Al and 36Cl in the dry valleys, Antarctica and in the Swiss Alps

    By measuring the concentration of a cosmogenic isotope (e.g. 10Be, 26Al, 36Cl), the length of time since formation or uncovering of a rock surface can be determined rather precisely. The useful time range of these isotopes is dependent upon the production rates, the half-lives as well as on sample analysis limitations. The interplay of the various factors is shown by two examples; the dating of very old surfaces in Antarctica and the dating of a Younger Dryas moraine in the Swiss Alps. (author) 1 fig., 3 refs

  1. Inventory of site-derived 36Cl in the Snake River plain aquifier, Idaho National Engineering Laboratory, Idaho

    Radioactive waste management practices at the U.S. Department of Energy's Idaho National Engineering Laboratory (INEL) in Idaho have introduced 36Cl (T1/2 = 301,000 yr) into the Snake River Plain aquifer underlying the site. The 36Cl is believed to originate from neutron activation of stable 35Cl in nuclear fuels (principally) and in reactor cooling/process water. Wastewater releases of 3H at the INEL have been documented by the site operators for the period 1952 to 1988. During this time, approximately 1.2 PBq of 3H (30,000 Ci) were introduced to the subsurface through disposal wells and seepage ponds. By sampling a number of monitoring and production wells downgradient from points of introduction, 3H movement and dispersion in the groundwater have been documented by the U.S. Geological Survey. The present report uses these historical 3H release and monitoring data to choose hydrologic parameters (matrix porosity and plume penetration depth) that produce concordance between the 3H release estimates and the inventory calculated from measurements of 3H in the subsurface. These parameters are then applied to 36Cl isopleths to generate an estimated 36Cl inventory in the subsurface. Using assumptions about irradiation times, neutron fluxes, and total fuel processed, as little as 23 g of stable chloride impurity in fuel elements would be adequate to produce the amount of 36Cl estimated to be in the groundwaters underlying the site. The highest atom concentration of 36Cl measured onsite (222x1010 atoms 1-1) corresponds to an activity level of ∼4 pCi 1-1 and represents 0.2 percent of the U.S. Environmental Protection Agency's (EPA) drinking water standard for this radionuclide (2000 pCi 1-1)

  2. Radiochemical analysis of 90Sr, 41Ca, 129I and 36Cl in waste samples

    Full text: The decommissioning of a nuclear facility requires estimating the total inventory of radioactivity in various materials and its variation with time, which has to be carried out by the determination of the radioactivity of various radionuclides presented in the materials. Of all materials in the nuclear facilities, graphite, concrete, and steel are the main low-medium radioactive waste due to their large volume. Besides the neutron activation products of components and impurity in the materials including 36Cl and 41Ca, some fission products, such as 90Sr, 99Tc, 129I, and 137Cs also exist in the materials due to the contamination of the leaked nuclear fuel. Of these radionuclides, the determination of gamma emitters is easier and can be directly carried out by gamma spectroscopy without any radiochemical separation. But the beta and alpha emitters including 3H, 14C, 36Cl, 41Ca, 55Fe, 63Ni, 90Sr, 9 and 129I and some transuranics, have to be determined by radiochemical analysis including a completely separation of individual radionuclides from matrix and other radionuclides before measurement by beta counting, alpha spectrometry or mass spectrometry. This work presents radiochemical analytical methods developed in our laboratory in the recent years for the determination of 36Cl, 41Ca, 90Sr and 129I in bio-shielding concrete, graphite and metals. for the decommissioning of nuclear facilities. Besides individual procedure for the purification of various radionuclides, a combined procedure is also developed and presented for the simultaneous determination of all four radionuclides from one sample. (author)

  3. Performance of the Chalk River 36Cl AMS system

    The MP Tandem Injector of the Chalk River TASCC (Tandem Accelerator Superconducting Cyclotron) Facility is being used for 36Cl determinations in studies relating to hydrology and low and high level nuclear waste management. In addition to the accelerator, the computer controlled system comprises a multiple-sample, medium-current ion source, a high resolution injector, a low resolution velocity filter, a gas filled magnet and a Bragg-type particle detection/identification system. Accuracies of 5--10% have been achieved with good suppression of 36S and background levels as low as 5x10-1536Cl/Cl. Following a brief overview of the system, detailed results are presented for the performance of the gas-filled magnet and particle detector as well as for sources of background including ion source memory effects

  4. Reconstruction of late glacial climates from the groundwater archive: Cl- and 36Cl in the Carrizo aquifer, Texas

    The climate history (temperature and precipitation minus evapotranspiration) of southern Texas was reconstructed for the past 35 ka, on the basis of groundwater data from the Carrizo aquifer. Palaeotemperatures derived from noble gases dissolved in groundwater indicate a mean annual temperature 5 deg. C lower than today for the last glacial maximum. Recharge rates (a measure of precipitation minus evapotranspiration) were estimated from Cl- and from 36Cl concentrations after performing corrections for variations of atmospheric Cl- and 36Cl deposition rates. The two lines of evidence are consistent and indicate that the recharge rate between 16 and 20 ka was up to to 100% higher than today. The occurrence of high lake levels in the Great Basin during that period suggests that the shift to a better climate during the late glacial was a common feature of the southwestern and southern United States of America. (author). 22 refs, 3 figs, 1 tab

  5. Inter-comparison of cosmogenic in-situ 3He, 21Ne and 36Cl at low latitude along an altitude transect on the SE slope of the Kilimanjaro volcano (3°S, Tanzania)

    Schimmelpfennig, I.; Williams, A.; Pik, R.; Burnard, P.; Niedermann, S.; Finkel, R. C.; Benedetti, L.; Schneider, B.

    2010-12-01

    Because the intensity and energy spectrum of the cosmic ray flux is affected by atmospheric depth and geomagnetic-field strength, cosmogenic nuclide production rates increase considerably with altitude and to a lesser degree with latitude. The scaling methods used to account for spatial variability in production rates assume that all cosmogenic nuclides have the same altitude dependence. In this study we evaluate whether the production rates of cosmogenic 36Cl, 3He and 21Ne change differently with altitude, which is plausible due to the different energy-thresholds of their production reactions. If so, nuclide-specific scaling factors would be required. Concentrations of the three cosmogenic nuclides were determined in mafic phenocrysts over an altitude transect between 1000 and 4300 m at Kilimanjaro volcano (3° S). Altitude-dependence of relative production rates was assessed in two ways: by determination of concentration ratios and by calculation of apparent exposure age ratios for all nuclide pairs. The latter accounts for characteristics of 36Cl that the stable nuclides 3He and 21Ne do not possess (radioactive decay, high sensitivity to mineral composition and significant contributions from production reactions other than spallation). All ratios overlap within error over the entire transect, and altitudinal variation in relative production rates is not therefore evident. This suggests that nuclide-specific scaling factors are not required for the studied nuclides at this low latitude location. However, because previous studies [1,2] documented anomalous altitude-dependent variations of 3He production at mid-latitude sites, the effect of latitude on cross-calibrations should be further evaluated. We determined cosmogenic 21Ne/3He concentration ratios of 0.187 ± 0.010 in pyroxenes and 0.375 ± 0.015 in olivines, agreeing with those reported in previous studies. Despite the absence of independently determined ages for the studied lava surfaces, the consistency in

  6. Activation Measurements for Thermal Neutrons, Part D. U.S. Measurements of 36Cl in Mineral Samples from Hiroshima and Nagasaki

    The present paper presents the 36Cl measurement effort in the US. A large number of 36Cl measurements have been made in both granite and concrete samples obtained from various locations and distances in Hiroshima and Nagasaki. These measurements employed accelerator mass spectrometry (AMS) to quantify the number of atoms of 36Cl per atom of total Cl in the sample. Results from these measurements are presented here and discussed in the context of the DS02 dosimetry reevaluation effort for Hiroshima and Nagasaki atomic-bomb survivors. The production of 36Cl by bomb neutrons in mineral samples from Hiroshima and Nagasaki was primarily via the reaction 35Cl(n,γ)36Cl. This reaction has a substantial thermal neutron cross-section (43.6 b at 0.025 eV) and the product has a long half-life (301,000 y). hence, it is well suited for neutron-activation detection in Hiroshima and Nagasaki using AMS more than 50 years after the bombings. A less important reaction for bomb neutrons, 39K(n,α)36Cl, typically produces less than 10% of the 36Cl in mineral samples such as granite and concrete, which contain ∼ 2% potassium. In 1988, only a year after the publication of the DS86 final report (Roesch 1987), it was demonstrated experimentally that 36Cl measured using AMS should be able to detect the thermal neutron fluences at the large distances most relevant to the A-bomb survivor dosimetry. Subsequent measurements in mineral samples from both Hiroshima and Nagasaki validated the experimental findings. The potential utility of 36Cl as a thermal neutron detector in Hiroshima was first presented by Haberstock et al. who employed the Munich AMS facility to measure 36Cl/Cl ratios in a gravestone from near the hypocenter. That work subsequently resulted in an expanded 36Cl effort in Germany that paralleled the US work. More recently, there have also been 36Cl measurements made by a Japanese group. The impetus for the extensive 36Cl and other neutron activation measurements was the

  7. Accelerator mass spectrometry of 36Cl produced by neutrons from the Hiroshima bomb

    Accelerator mass spectrometry was performed at the Munich tandem laboratory to determine 36Cl/Cl ratios of samples from a tombstone exposed to neutrons from the Hiroshima bomb. The ratios were determined from the surface to deeper positions. The depth profile of 36Cl/Cl can be used for estimating the neutron energy distribution and intensity near the hypocentre in Hiroshima. (author)

  8. Radiological assessment of 36Cl in the disposal of used CANDU fuel

    An assessment of the potential radiological impact of 36Cl in the disposal of used CANDU fuel has been performed. The assessment was based on new data on chlorine impurity levels in used fuel. Data bases for the vault, geosphere, and biosphere models used in the EIS postclosure assessment case study (Goodwin et al. 1994) were modified to include the necessary 36Cl data. The resulting safety analysis shows that estimated radiological risks from 36Cl are forty times lower than from 129I at 104 a; this, incorporation of 36Cl into the models does not change the overall conclusions of the study of Goodwin et al. (1994a). For human intrusion scenarios, an analysis using the methodology of Wuschke (1992) showed that the maximum risk is unaffected by the inclusion of 36Cl. (author). 51 refs., 5 tabs., 15 figs

  9. Determination of 36Cl in biological shield concrete using pyrohydrolysis and liquid scintillation counting.

    Itoh, Mitsuo; Watanabe, Kazuo; Hatakeyama, Mutsuo; Tachibana, Mitsuo

    2002-07-01

    A method for the determination of 36Cl in biological shield concrete of nuclear reactors was developed. Cl in the concrete sample was extracted quantitatively by pyrohydrolysis at 900 degrees C and recovered in Na2CO3 solution for subsequent measurement of 36Cl by liquid scintillation counting. WO3 was used as an accelerator in the pyrohydrolysis. The Cl extraction procedure was optimized by investigating experimental conditions with the use of ion chromatography and its recovery was evaluated by the analysis of the geochemical reference samples. The detection limit of 36Cl was 0.02 Bq g(-1) for a sample weight of 2 g. The relative standard deviation was 3-7% for the samples containing 0.5 Bq g(-1) levels of 36Cl. The method was applied to determine 36Cl in biological shield concrete of the Japan Power Demonstration Reactor. PMID:12173658

  10. The Hiroshima thermal-neutron discrepancy for (36)Cl at large distances. Part I: New (36)Cl measurements in granite samples exposed to A-bomb neutrons.

    Huber, Thomas; Rühm, Werner; Kato, Kazuo; Egbert, Stephen D; Kubo, Florian; Lazarev, Vitali; Nolte, Eckehart

    2005-10-01

    The long-lived radioisotope (36)Cl (half-life: 301,000 years) was measured in granite samples exposed to A-bomb neutrons at distances from 94 to 1,591 m from the hypocenter in Hiroshima, by means of accelerator mass spectrometry (AMS). Measured (36)Cl/Cl ratios decrease from 1.6 x 10(-10) close to the hypocenter to about 1-2 x 10(-13), at a distance of 1,300 m from the hypocenter. At this distance and beyond the measured (36)Cl/Cl ratios do not change significantly and scatter around values of 1-2 x 10(-13). These findings suggest that the (36)Cl had been predominantly produced by thermalized neutrons from the A-bomb via neutron capture on stable (35)Cl, at distances from the hypocenter smaller than about 1,200 m. At larger distances, however, confounding processes induced by cosmic rays or neutrons from the decay of uranium and thorium become important. This hypothesis is theoretically and experimentally supported in a consecutive paper. The results are compared to calculations that are based on the most recent dosimetry system DS02. Close to the hypocenter, measured (36)Cl/Cl ratios are lower than those calculated, while they are significantly higher at large distances from the hypocenter. If the contribution of the cosmic rays and of the neutrons from the decay of uranium and thorium in the sample was subtracted, however, no significant deviation from the DS02 calculations was observed, at those distances. Thus, the Hiroshima neutron discrepancy reported in the literature for (36)Cl for samples from large distances from the hypocenter, i.e., higher measured (36)Cl/Cl ratios than predicted by the previous dosimetry system DS86, was not confirmed. PMID:16177928

  11. 36Cl and 14C behaviour in UNGG graphite during leaching experiments

    Graphite has been used as a moderator in Natural Uranium Graphite Gas reactors. Among the radionuclides, the long-lived activation product 36Cl and 14C, which are abundant in graphite after irradiation can be the main contributors to the dose during disposal. This paper deals with the first results obtained on irradiated graphite from French G2 reactor. Both leaching and diffusion experiments have been performed in order to understand and quantify the radionuclides behaviour. Chlorine leaching seems to be controlled by diffusion transport through graphite matrix. On the contrary 14C leaching is very low, probably because after irradiation, the remaining 14C was produced from 13C activation in the crystalline structure of graphite. (authors)

  12. Groundwater dilution and residence times, and constraints on chloride source, in the Mokai geothermal system, New Zealand, from chemical, stable isotope, tritium, and 36Cl data

    The maximum measured temperature of the production wells is near 323C at 2500 m depth, whereas temperatures in two wells on the northern margin of the upflow are 36Cl/Cl ratio of 2.6 x 10-15 and a 36Cl concentration of 106 atoms per 10-6 kg. This fluid has a lower ration (by a factor of 90) and a higher absolute concentration (by a factor of 7) than present-day stream water. However, the marginal wells have been diluted by groundwater with at least 500 36Cl atoms per 10-6 kg, 30 times richer in 36Cl than present-day stream waters. This spike is most likely due to circulation of precipitation formed during thermonuclear testing to depths of 1,000 m. The amount of 36Cl in the deep fluid at Mokai is 5-10 times less than that predicted from a calculation of the neutron fluxes in the silicic reservoir and underlying greywacke basement rocks. This indicates that the fluids have interacted with more primitive rocks below the drilled depths of the Taupo Volcanic Zone, with the chloride possibly derived from a magmatic brine

  13. New approaches investigating production rates of in-situ produced terrestrial cosmogenic nuclides

    Merchel, Silke [CEREGE, CNRS-IRD-Universite Aix-Marseille, Aix-en-Provence (France); FZD, Dresden (Germany); Braucher, Regis; Benedetti, Lucilla; Bourles, Didier [CEREGE, CNRS-IRD-Universite Aix-Marseille, Aix-en-Provence (France)

    2010-07-01

    In-situ produced cosmogenic nuclides have proved to be valuable tools for environmental and Earth sciences. However, accurate application of this method is only possible, if terrestrial production rates in a certain environment over a certain time period and their depth-dependence within the exposed material are exactly known. Unfortunately, the existing data and models differ up to several tens of percent. Thus, one of the European project CRONUS-EU goals is the high quality calibration of the {sup 36}Cl production rate by spallation at independently dated surfaces. As part of fulfilling this task we have investigated calcite-rich samples from four medieval landslide areas in the Alps: Mont Granier, Le Claps, Dobratsch, and Veliki Vrh (330-1620 m, 1248-1442 AD). For investigating the depth-dependence of the different nuclear reactions, especially, the muon- and thermal neutron-induced contributions, we have analysed mixtures of carbonates and siliceous conglomerate samples - for {sup 10}Be, {sup 26}Al, and {sup 36}Cl - exposed at different shielding depths and taken from a core drilled in 2005 at La Ciotat, France (from surface to 11 m shielding). AMS of {sup 36}Cl was performed at LLNL and ETH, {sup 10}Be and {sup 26}Al at ASTER.

  14. Radiochemical determination of 129I and 36Cl in MEGAPIE, a proton irradiated lead-bismuth eutectic spallation target

    The concentrations of the long-lived nuclear reaction products 129I and 36Cl have been measured in samples from the MEGAPIE liquid metal spallation target. Samples from the bulk target material (lead-bismuth eutectic, LBE), from the interface of the metal free surface with the cover gas, from LBE/steel interfaces and from noble metal absorber foils installed in the cover gas system were analysed using Accelerator Mass Spectrometry at the Laboratory of Ion beam Physics at ETH Zuerich. The major part of 129I and 36Cl was found accumulated on the interfaces, particularly at the interface of LBE and the steel walls of the target container, while bulk LBE samples contain only a minor fraction of these nuclides. Both nuclides were also detected on the absorber foils to a certain extent (<< 1% of the total amount). The latter number is negligible concerning the radio-hazard of the irradiated target material; however it indicates a certain affinity of the absorber foils for halogens, thus proving the principle of using noble metal foils for catching these volatile radionuclides. The total amounts of 129I and 36Cl in the target were estimated from the analytical data by averaging within the different groups of samples and summing up these averages over the total target. This estimation could account for about half of the amount of 129I and 36Cl predicted to be produced using nuclear physics modelling codes for both nuclides. The significance of the results and the associated uncertainties are discussed.

  15. Surface exposure history using in-situ cosmogenic 10Be, 26Al and 36Cl - applications to the Australian environment

    Production of the long-lived cosmogenic radionuclides, 10Be (T1/2=1.5Ma), 26Al (0.7Ma) and 36Cl (0.3Ma), is dominated by the interaction of cosmic-rays with the upper atmosphere. They are also produced in exposed surface rocks and within the first meter or so of the Earth's crust. This is called in-situ production and although only a million atoms or so of 10Be are produced within a ten thousand year exposure period per gram of surface rock, the technique of Accelerator Mass Spectrometry (AMS) can be applied to measure this tell-tale signal. The build-up over time of these radionuclides can be utilised as radiometric clocks to elucidate the exposure history of geomorphic formations and surfaces that have experienced some event or process that delivers previously unexposed material to cosmic-ray irradiation. Hence the reconstruction of glacial chronologies (ie time a bedrock surface was uncovered by ice retreat, or deposition age of glacial moraines), development of raised river terraces and paleo-beach ridges, age of meteorite impact craters and volcanic eruptions have been addressed with the in-situ method. Moreover, geomorphological processes of landscape evolution such as surface erosion rates, continental weathering, sediment transport and deposition, uplift rates can also be studied. The in-situ method is described along with examples of cosmogenic dating projects at ANSTO. It is estimated that it works best over the time period from 5 ka to 5 Ma and can identify erosion rates ranging from 0.1 to 10 mm/ka

  16. Measurements of 36Cl in Antarctic meteorites and Antarctic ice using a Van de Graaff accelerator

    Cosmic-ray produced 36Cl(tsub(1/2) = 3.0 X 105 years) has been measured in four Antarctic meteorites and one sample of Antarctic ice using a tandem Van de Graaff accelerator as an ultrasensitive mass spectrometer with the extremely low background level of 36Cl/Cl -16. Results from this ion counting technique (applied here to extraterrestrial materials for the first time) are used to support a two-stage irradiation model for the Yamato-7301and Allan Hills-76008 meteorites and to show a long terrestrial age (0.7 +- 0.1 m.y.) for Allan Hills-77002. Yamato-7304 has a terrestrial age of less than 0.1 m.y. The 36Cl content of the Antarctic ice sample from the Yamato Mountain area implies that the age of the ice cap at this site is less than one 36Cl half-life. (Auth.)

  17. 36Cl-Messungen zur Erklärung der Neutronen-Diskrepanz von Hiroshima

    Huber, Thomas Christian

    2007-01-01

    Messungen von Radionukliden, die in Hiroshima durch thermische Neutronen produziert wurden, zeigten Unterschiede zu den im Dosimetriesystem DS86 gerechneten Werten. Dies wurde in der Literatur oft als sogenannte Hiroshima Diskrepanz bezeichnet. Im Rahmen dieser Arbeit wurde 36Cl, das durch thermische Neutronen produziert wurde, in Granit-Proben aus Hiroshima gemessen. Durch Korrektur der in dieser Arbeit erhaltenen Messwerte von Proben aus Hiroshima mit gerechneten natürlichen 36Cl-Konzentrat...

  18. AMS analysis of 36Cl induced in concrete of accelerator facilities

    Accelerator mass spectrometry (AMS) was applied to the analysis of 36Cl induced in concrete samples obtained from accelerator facilities. In order to use a small amount of concrete sample and to separate chlorine as pure as possible, an improvement of separation process was developed. Chlorine was extracted from 1-5 g of concrete into 0.01 M nitric acid in a pressurized decomposition vessel. After determining chlorine using ion chromatography, a certain amount of NaCl solution was added to obtain sufficient amounts of AgCl precipitate and to dilute to a suitable isotope ratio of 36Cl to 35Cl (36Cl/35Cl) for the AMS (10-12-10-10). A careful purification procedure was applied to reduce 36S interference in AMS. Good reproducibility and small error throughout the chemical process for sample preparation was attained. Depth profiles of 36Cl/35Cl in concrete of a medium-energy cyclotron were measured by the developed method and compared with the results of γ-emitters induced by thermal neutrons. Since it was confirmed that 36Cl was produced by thermal neutron capture of 35Cl, the thermal neutron fluence irradiated during accelerator operation could be obtained using 36Cl/35Cl. In order to estimate the neutron fluences, the 36Cl/35Cl measurement by AMS is more useful than radioactivity measurements of other isotopes such as γ-emitters because AMS directly provides the isotope ratio and the half-life of 36Cl is very long. (orig.)

  19. Accelerator mass spectrometry of 36Cl produced by neutrons from the Hiroshima bomb.

    Kato, K; Habara, M; Yoshizawa, Y; Biebel, U; Haberstock, G; Heinzl, J; Korschinek, G; Morinaga, H; Nolte, E

    1990-10-01

    Accelerator mass spectrometry was performed at the Munich tandem laboratory to determine 36Cl/Cl ratios of samples from a tombstone exposed to neutrons from the Hiroshima bomb. The ratios were determined from the surface to deeper positions. The depth profile of 36Cl/Cl can be used for estimating the neutron energy distribution and intensity near the hypocentre in Hiroshima. PMID:1976726

  20. Determination of 36Cl/Cl ratio in ground water using the accelerator mass spectrometry technique

    The Accelerator Mass Spectrometry (AMS) programme using the 14 MV Pelletron Accelerator at Mumbai has been initiated with major emphasis on the determination of 36Cl in water samples, of interest to hydrology and environment. In order to carry out the AMS measurement, a beam chopper to cut down beam intensity by a factor of 20 has been developed and commissioned. A multi-anode gas -si detector has been built to separate 36Cl from the interfering 36S. A new TPS system has been procured to operate the machine in the GVM mode. Standard and blank samples from Prime lab, Purdue have been employed in these measurements to standardise the technique for 36Cl/Cl ratio determination. The detector was calibrated using the stable 35,37Cl ions. The background 36Cl in the system has been measured using the blank sample from Purdue and it was estimated that the ratio of 36Cl/Cl was of the order of 10-13 in the present setup. Ground water samples collected from South India were converted to AgCl and put in the SNICS ion source for the AMS measurements. These ground water samples, with 14C content estimated to be in the range of 1 to 4 pMC indicate that the samples may be more than 35,000 years old. Using the AMS technique we have determined the 36Cl/Cl ratio values for these ground water samples. They are found to range between 2 to 5 x 10-12. Additional measurements are planned to determine the age of the water samples and to understand the reasons for the observed high values of 36Cl in these samples. (author)

  1. Hith resolution {beta}-spectroscopy of the isotope {sup 36}Cl using magnetic calorimeters; Entwicklung magnetischer Mikrokalorimeter fuer die hochaufloesende Spektroskopie des {beta}-Emitters {sup 36}Cl

    Rotzinger, H.

    2006-12-13

    This thesis describes the development of a high resolution magnetic calorimeter for the detection of the {beta}-spectrum of the isotope {sup 36}Cl with endpoint energy of 709.6 keV. The temperature rise of a metallic paramagnetic sensor due to an energy deposition is sensed by measuring its magnetization using a sensitive DC-SQUID magnetometer. For a high detection efficiency an 4{pi} gold absorber was used. The heat capacity and the geometry of the absorber is optimally matched by a flat sensor and an optimized meander shaped readout coil. The fabrication of the superconducting structures and the detector setup are described. In addition, the relevant noise sources, the energy resolution and the quantum efficiency are discussed. A measured {sup 36}Cl-spectrum with an energy resolution of {delta}E{sub FWHM}=750 eV is presented and compared with existing experimental and theoretical data. (orig.)

  2. Ethanol enhances GABA-induced 36Cl-influx in primary spinal cord cultured neurons

    Ethanol has a pharmacological profile similar to other centrally acting drugs, which facilitate GABAergic transmission. GABA is known to produce its effects by increasing the conductance to Cl- ions. In this study, we have examined the effect of ethanol on GABA-induced 36Cl-influx in primary spinal cord cultured neurons. GABA produces a concentration-dependent, and saturable effect on 36Cl-influx in these neurons. Ethanol potentiates the effect of GABA on 36Cl-influx in these neurons. GABA (20 microM) increased the 36Cl-influx by 75% over the basal value, and in the presence of 50 mM ethanol, the observed increase was 142%. Eadie-Hoffstee analysis of the saturation curves indicated that ethanol decreases the Km value of GABA (10.6 microM to 4.2 microM), and also increases the Vmax. Besides potentiating the effect of GABA, ethanol also appears to have a direct effect in the absence of added GABA. These results suggest that ethanol enhances GABA-induced 36Cl-influx and indicate a role of GABAergic system in the actions of ethanol. These results also support the behavioral and electrophysiological studies, which have implicated GABA systems in the actions of ethanol. The potential mechanism(s) and the role of direct effect of ethanol is not clear at this time, but is currently being investigated

  3. Measurement of the natural 36Cl and 236U uranium mineral with accelerator mass spectrometry

    The concentration of the natural ultra-trace radionuclides 36Cl and 236U in the uranium depended on the neutron flux. In this article, a method for measuring 36Cl and 236U in the same uranium mineral with accelerator mass spectrometry was developed in China Institute of Atomic Energy, providing a protocol of the potential application of 236U in uranium mining, environmental, and geological research. The two samples were from Guangxi and Shanxi province, China, and their ratios 36Cl/Cl and 236U/238U were measured. More experimental data conduced to understand the natural nuclides in the uranium mineral. We plan to conduct more efforts on the research. (authors)

  4. Attempt to determine the environmental 36Cl concentration in water by liquid scintillation counting

    Florkowski, T.; Schuszler, Ch.

    1986-11-01

    A low-background liquid scintillation spectrometer (ALOKA SL-1) located in the IAEA Isotope Hydrology Laboratory in Vienna was used for 36Cl activity measurement in water samples. The procedure of sample preparation consists of synthesizing of silicon tetrachloride or sodium chloride followed by purification. In both cases the limiting factor in the analysis appeared to be the pure reproducibility of the sample preparation procedure. The conclusion from these experiments is that the liquid scintillation method could be feasible only for the identification of the "bomb chlorine" but is far from being suitable for the accurate determination of 36Cl in groundwater for dating purposes.

  5. Determination of {sup 10}Be, {sup 26}Al, and {sup 36}Cl in meteorites

    Merchel, S.; Herpers [Koeln Univ. (Germany); Neumann, S.; Michel, R. [Hannover Univ. (Germany); Kubik, P.W.; Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Long-lived cosmogenic radionuclides were determined in stony ({sup 10}Be, {sup 26}Al) and iron ({sup 10}Be, {sup 26}Al, {sup 36}Cl) meteorites using AMS after radiochemical separation. A selection of these data is briefly discussed with respect to exposure histories of the meteorites and is compared to model calculations. (author) 2 figs., 5 refs.

  6. Distribution and chemical fate of 36Cl-chlorine dioxide gas during the fumigation of tomatoes and cantaloupe

    The distribution and chemical fate of 36Cl-ClO2 gas subsequent to fumigation of tomatoes or cantaloupe was investigated as was major factors that affect the formation of chloroxyanion byproducts. Approximately 22% of the generated 36Cl-ClO2 was present on fumigated tomatoes after a 2-hour exposure t...

  7. Investigation of the reaction 35Cl(n,γ)36Cl

    The γ-radiation following capture of non-polarized thermal neutrons in 35Cl has been investigated. Of the 420 γ-rays ascribed to the 35Cl(n,γ)36Cl reaction, 236 have been placed in a 36Cl decay scheme. The branching ratios and the excitation energies (with 0.04-0.9 KeV errors) of 72 bound states have been determined. Spin assignments and spin restrictions or confirmations have been made for a total of 20 levels. The multipole mixing ratios for some primary γ-ray transitions have been determined. There exists a significant correlation between (d,p) stripping strengths and (n,γ) reduced primary transition probabilities for transitions to lsub(n)(d,p) = 0 levels

  8. Depth dependence of soil carbonate accumulation based on cosmogenic 36Cl dating

    Liu, Beiling; Phillips, Fred M.; Elmore, David; Sharma, Pankaj

    1994-12-01

    Indurated pedogenic carbonate layers (calcretes) are common in soils on stable surfaces in arid to semiarid climates. The morphology and composition of calcretes provide important information on the geomorphic and climatic histories of the regions where they are formed, but they have proved difficult to date with conventional radiometric methods. We report cosmogenic 36Cl-buildup ages from three fractions (leachable Cl, carbonate, silicate) of a calcrete from the surface of an alluvial slope below the Ajo Mountains in southern Arizona. All three fractions give reasonably concordant ages, ranging from 700 ka at the base of the calcrete horizon to 200 ka at its top. These ages are in good agreement both with estimates of age based on correlation with similar, independently dated, soils in the region and with 36Cl-buildup ages on surficial boulders. These results support the ideas that calcretes accumulate upward with time and that water movement through the carbonate matrix is very limited after induration.

  9. Determination of 36Cl in JCO samples by AMS at Tsukuba

    Chlorine-36 in environmental samples collected at JCO criticality accident site has been measured by accelerator mass spectrometer (AMS). The atomic ratio of 36Cl/Cl in the soil sample (10 m of the reactor vessel) was 11 x 10-12, which corresponds to a thermal neutron flux of 2.5 x 1011 cm-2. This ratio is higher than calculated ratio, 4.2 x 10-12 by Imanaka (Kyoto Univ.). Furthermore we collected more soil samples in Tokai within 10 km from JCO site and Tsukuba, 60 km far from Tokai. The 36Cl/Cl ratios in some soil samples showed higher than in JCO site. The origin of the higher ratios has not been clarified. (author)

  10. Cosmogenic in situ production of radionuclides: Exposure ages and erosion rates

    Experimental data for the cosmogenic in situ production of radionuclides and its depth dependence are used for two applications, the determination of exposure ages and of erosion rates. Concentrations of the long-lived radionuclides 10Be, 14C and 26Al in quartz are presented as function of exposure age, depth before exposure and erosion rate after exposure. It is shown that the cosmogenic production before exposure can introduce important corrections to the representation without consideration of pre-exposure production. Depth profiles of 10Be, 14C and 26Al in quartz and sulfur, of 36Cl in K2O, CaCO3, granite and concrete and of 53Mn in Fe2O3 are given as function of erosion rate. Consequences to determinations of neutron fluences in Hiroshima are discussed

  11. Accelerator mass spectrometry with fully stripped 26Al, 36Cl, 41Ca and 59Ni ions

    The detection system of accelerator mass spectrometry (AMS) with completely stripped ions of 26Al, 36Cl, 41Ca and 59Ni at the Munich accelerator laboratory and measurements with these ions are presented. Detection limits are given. The presented applications are: dating of groundwater of the Milk River aquifer and deduction of the neutron fluence and spectrum of the Hiroshima A-bomb. (orig.)

  12. Radiochemical determination of {sup 129}I and {sup 36}Cl in MEGAPIE, a proton irradiated lead-bismuth eutectic spallation target

    Hammer-Rotzler, Bernadette; Tuerler, Andreas [Paul Scherrer Institut (PSI), Villigen (Switzerland); Bern Univ. (Switzerland); Neuhausen, Joerg; Boutellier, Viktor; Wohlmuther, Michael; Schumann, Dorothea [Paul Scherrer Institut (PSI), Villigen (Switzerland); Vockenhuber, Christof [ETH Zurich (Switzerland). Lab. of Ion Beam Physics

    2015-07-01

    The concentrations of the long-lived nuclear reaction products {sup 129}I and {sup 36}Cl have been measured in samples from the MEGAPIE liquid metal spallation target. Samples from the bulk target material (lead-bismuth eutectic, LBE), from the interface of the metal free surface with the cover gas, from LBE/steel interfaces and from noble metal absorber foils installed in the cover gas system were analysed using Accelerator Mass Spectrometry at the Laboratory of Ion beam Physics at ETH Zuerich. The major part of {sup 129}I and {sup 36}Cl was found accumulated on the interfaces, particularly at the interface of LBE and the steel walls of the target container, while bulk LBE samples contain only a minor fraction of these nuclides. Both nuclides were also detected on the absorber foils to a certain extent (<< 1% of the total amount). The latter number is negligible concerning the radio-hazard of the irradiated target material; however it indicates a certain affinity of the absorber foils for halogens, thus proving the principle of using noble metal foils for catching these volatile radionuclides. The total amounts of {sup 129}I and {sup 36}Cl in the target were estimated from the analytical data by averaging within the different groups of samples and summing up these averages over the total target. This estimation could account for about half of the amount of {sup 129}I and {sup 36}Cl predicted to be produced using nuclear physics modelling codes for both nuclides. The significance of the results and the associated uncertainties are discussed.

  13. Methyl salicylate as a medium for radioassay of 36Cl using a liquid scintillation spectrometer

    Methyl salicylate (MS), a high refractive index liquid with wave-shifting properties, has been used as a Cherenkov radiation generating medium for the radioassay of 36Cl by liquid scintillation (LS) spectrometer. Comparative experiments, using both a standard toluene-based LS fluor and toluene alone, for the measurement of 36Cl were undertaken. The methyl salicylate medium was found to perform at an intermediate counting efficiency, near that for the LS fluor. In the presence of moderate amounts of nitromethane, the MS was less susceptible to chemical quenching effects than either the fluor or toluene. Counting efficiencies for 36Cl in MS, toluene and toluene fluor respectively were 82.4, 28.4 and 100.3 percent with a Picker Liquimat 220 LS spectrometer, and 91.6, 54.9 and 100.0 percent with a Searle Mark III LS spectrometer. The addition of nitromethane (11.3 percent of final volume) reduced these efficiencies to 50.5, 10.0 and 15.4 percent, and to 58.8, 12.4 and 19.0 percent, respectively. The data are discussed in relation to observed changes in the pulse height spectra. Chemical quench correction by ESCR and by SCR methods is reported

  14. An Alluvial Surface Chronology Based on Cosmogenic 36Cl Dating, Ajo Mountains (Organ Pipe Cactus National Monument), Southern Arizona

    Liu, Beiling; Phillips, Fred M.; Pohl, Molly M.; Sharma, Pankaj

    1996-01-01

    A chronology of alluvial surfaces on piedmont slopes below the western Ajo Mountains, southern Arizona, has been obtained using cosmogenic 36Cl accumulation and AMS radiocarbon dating. The apparent 36Cl ages of individual boulders range from 520,000 to 13,000 yr, and the 14C ages of organic material in the two young terraces are 2750-2350 and 17,800 cal yr B.P. The sequence of 36Cl ages is consistent with the apparent stratigraphic order, but groupings of similar ages for different surfaces appear to result from repeated reworking of older surfaces associated with the deposition of younger ones. The youngest surface gave a distribution of 36Cl ages about 30,000 yr older than the 14C and soil ages; however, this distribution had 36Cl ages that overlapped with 36Cl ages from active channels and hillslopes. We attribute the older-than-expected exposure ages of sampled boulders to inheritance of 36Cl while residing near the surface during very slow erosion on the mountain front. Our results show that although cosmogenic nuclide accumulation can help establish chronologies for surfaces in piedmont settings, care must be used in evaluating the effects of complex exposure histories.

  15. Surface exposure history using in-situ cosmogenic {sup 10}Be, {sup 26}Al and {sup 36}Cl - applications to the Australian environment

    Fink, D. [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia). Physics Division

    1999-11-01

    Production of the long-lived cosmogenic radionuclides, {sup 10}Be (T{sub 1/2}=1.5Ma), {sup 26}Al (0.7Ma) and {sup 36}Cl (0.3Ma), is dominated by the interaction of cosmic-rays with the upper atmosphere. They are also produced in exposed surface rocks and within the first meter or so of the Earth`s crust. This is called in-situ production and although only a million atoms or so of {sup 10}Be are produced within a ten thousand year exposure period per gram of surface rock, the technique of Accelerator Mass Spectrometry (AMS) can be applied to measure this tell-tale signal. The build-up over time of these radionuclides can be utilised as radiometric clocks to elucidate the exposure history of geomorphic formations and surfaces that have experienced some event or process that delivers previously unexposed material to cosmic-ray irradiation. Hence the reconstruction of glacial chronologies (ie time a bedrock surface was uncovered by ice retreat, or deposition age of glacial moraines), development of raised river terraces and paleo-beach ridges, age of meteorite impact craters and volcanic eruptions have been addressed with the in-situ method. Moreover, geomorphological processes of landscape evolution such as surface erosion rates, continental weathering, sediment transport and deposition, uplift rates can also be studied. The in-situ method is described along with examples of cosmogenic dating projects at ANSTO. It is estimated that it works best over the time period from 5 ka to 5 Ma and can identify erosion rates ranging from 0.1 to 10 mm/ka 20 refs., 4 figs.

  16. Modelling water and 36Cl cycling in a Belgian pine forest - Model for 36Cl cycling in a Belgian pine forest

    A simplified, 1-D soil-groundwater-vegetation model to represent the cycling of water and of 36Cl in a Belgian Scots pine forest is presented and discussed. The model contains a soil column with layers of different (but uniform) field capacity and soil porosity, which are penetrated by tree roots. Flow through porous media is assumed to circulate according to Darcy and Philips laws, using empirical soil hydraulic properties without recourse to Richards' equation. The vegetation is represented by means of a compartment model including simplified representation of sap flow, translocation and litterfall in relation to different parts of the tree. The water table height is variable according to the balance between precipitation, capillary rise, solar radiation, plant uptake and evapotranspiration. The influence of local fluvial sources of water can also be evaluated in a simplified way as a losing/gaining stream input to the soil column. Time dependent data on temperature, solar irradiation, rainfall, crop coefficient and leaf area index (LAI) are used as input to the model in order to calculate evapotranspiration and a simplified approach to foliar interception. The chlorine flux follows the water flux in both soil and the trees, using retardation in soil and experimentally measured translocation factors within the plant. The chlorine flux is optimised and validated with recourse to a previous 36Cl compartment model. Although considered to be a relatively simple model, initial results suggest a reasonable consistency between previously published water balance and field measurements in a Scots pine stand from the vicinity of Mol, Belgium. The mean soil water content is predicted to be around 25%, the plant water is stored in the order roots > plant above roots > leaf surfaces, water table height below ground fluctuates between 2.1 and 2.6 m compared with a measured water table height of 1.8 - 20 m and pine transpiration is less than 1.2 mm/d compared with a measured

  17. Modelling water and {sup 36}Cl cycling in a Belgian pine forest - Model for {sup 36}Cl cycling in a Belgian pine forest

    Vives i Batlle, Jordi; Vandenhove, Hildegarde; Gielen, Sienke [Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium)

    2014-07-01

    A simplified, 1-D soil-groundwater-vegetation model to represent the cycling of water and of {sup 36}Cl in a Belgian Scots pine forest is presented and discussed. The model contains a soil column with layers of different (but uniform) field capacity and soil porosity, which are penetrated by tree roots. Flow through porous media is assumed to circulate according to Darcy and Philips laws, using empirical soil hydraulic properties without recourse to Richards' equation. The vegetation is represented by means of a compartment model including simplified representation of sap flow, translocation and litterfall in relation to different parts of the tree. The water table height is variable according to the balance between precipitation, capillary rise, solar radiation, plant uptake and evapotranspiration. The influence of local fluvial sources of water can also be evaluated in a simplified way as a losing/gaining stream input to the soil column. Time dependent data on temperature, solar irradiation, rainfall, crop coefficient and leaf area index (LAI) are used as input to the model in order to calculate evapotranspiration and a simplified approach to foliar interception. The chlorine flux follows the water flux in both soil and the trees, using retardation in soil and experimentally measured translocation factors within the plant. The chlorine flux is optimised and validated with recourse to a previous {sup 36}Cl compartment model. Although considered to be a relatively simple model, initial results suggest a reasonable consistency between previously published water balance and field measurements in a Scots pine stand from the vicinity of Mol, Belgium. The mean soil water content is predicted to be around 25%, the plant water is stored in the order roots > plant above roots > leaf surfaces, water table height below ground fluctuates between 2.1 and 2.6 m compared with a measured water table height of 1.8 - 20 m and pine transpiration is less than 1.2 mm/d compared

  18. Preparation and characterization of sup 35 Cl and sup 36 Cl samples for (n,p) cross section measurements

    Eykens, R.; Goetz, A.; Lamberty, A.; Gestel, J. van; Pauwels, J. (Commission of the European Communities, Joint Research Centre, Central Bureau for Nuclear Measurements, Geel (Belgium)); Wagemans, C.; Druyts, S. (Nuclear Physics Lab., State Univ., Ghent (Belgium)); Hondt, P. d' (SCK/CEN, Mol (Belgium))

    1991-05-15

    The {sup 35}Cl(n,p) and the {sup 36}Cl(n,p) reactions are of great importance for astrophysics. Several silver chloride samples were evaporated on platinum coated aluminium backings. The sample definition has been achieved by combining destructive and non-destructive methods. The isotopic composition of the {sup 36}Cl-enriched material was verified. Pulse height spectra of {sup 35}Cl(n{sub th},p) and {sup 36}Cl(n{sub th},p) are shown. The samples prepared and assayed in this way have proven to fulfil the experimental requirements and have been used to determine the reaction cross sections of {sup 35}Cl(n{sub th},p) and {sup 36}Cl(n{sub th},p). (orig.).

  19. AMS Measurement of 36Cl With a Gas-filled Time of Flight Detector

    GUANYong-jing; HEMing; RUANXiang-dong; WANGHui-juan; LIGuo-qiang; WUShao-yong; WUWei-ming; JIANGShan

    2003-01-01

    In order to determine 36Cl and 36S with high sensitivity by AMS, the present study has been done.Difference of time flight in the gas dependences to total energy, gas pressure in the chamber, and the flight length for isobars. The time resolution (FWHM) of the detector system is 800 ps without gas-filled when the ion energy is 72 MeV. Time straggling is growth with the increase of gas pressure in the chamber.Time straggling caused by the gas pressure is shown in Fig.1.

  20. Chloride isolation for accelerator mass spectrometry of 36Cl produced by atomic bomb neutrons

    Accelerator mass spectrometry was performed at the Munich tandem laboratory to determine the ratio of 36Cl/Cl in silicate rock samples exposed to neutrons of the Hiroshima atomic bomb. Chloride was chemically separated from silicate rock for this purpose. Five grams of silicate rock was fused with 30 g of sodium hydroxide and dissolved in 900 ml of water. The chloride in the resulting solution was spectrophotometrically determined. Chloride was precipitated as silver chloride by addition of appropriate amounts of silver nitrate, and silver chloride was then collected on a membrane filter. The chloride in the rock samples was thus isolated quantitatively. (author)

  1. Intercomparison study on (152)Eu gamma ray and (36)Cl AMS measurements for development of the new Hiroshima-Nagasaki Atomic Bomb Dosimetry System 2002 (DS02).

    Hoshi, M; Endo, S; Tanaka, K; Ishikawa, M; Straume, T; Komura, K; Rühm, W; Nolte, E; Huber, T; Nagashima, Y; Seki, R; Sasa, K; Sueki, K; Fukushima, H; Egbert, S D; Imanaka, T

    2008-07-01

    In the process of developing a new dosimetry system for atomic bomb survivors in Hiroshima and Nagasaki (DS02), an intercomparison study between (152)Eu and (36)Cl measurements was proposed, to reconcile the discrepancy previously observed in the Hiroshima data between measurements and calculations of thermal neutron activation products. Nine granite samples, exposed to the atomic-bomb radiation in Hiroshima within 1,200 m of the hypocenter, as well as mixed standard solutions containing known amounts of europium and chlorine that were neutron-activated by a (252)Cf source, were used for the intercomparison. Gamma-ray spectrometry for (152)Eu was carried out with ultra low-background Ge detectors at the Ogoya Underground Laboratory, Kanazawa University, while three laboratories participated in the (36)Cl measurement using accelerator mass spectrometry (AMS): The Technical University of Munich, Germany, the Lawrence Livermore National Laboratory, USA and the University of Tsukuba, Japan. Measured values for the mixed standard solutions showed good agreement among the participant laboratories. They also agreed well with activation calculations, using the neutron fluences monitored during the (252)Cf irradiation, and the corresponding activation cross-sections taken from the JENDL-3.3 library. The measured-to-calculated ratios obtained were 1.02 for (152)Eu and 0.91-1.02 for (36)Cl, respectively. Similarly, the results of the granite intercomparison indicated good agreement with the DS02 calculation for these samples. An average measured-to-calculated ratio of 0.98 was obtained for all granite intercomparison measurements. The so-called neutron discrepancy that was previously observed and that which included increasing measured-to-calculated ratios for thermal neutron activation products for increasing distances beyond 1,000 m from the hypocenter was not seen in the results of the intercomparison study. The previously claimed discrepancy could be explained by

  2. Ion irradiation of 37Cl implanted nuclear graphite: Effect of the energy deposition on the chlorine behavior and consequences for the mobility of 36Cl in irradiated graphite

    Graphite is used in many types of nuclear reactors due to its ability to slow down fast neutrons without capturing them. Whatever the reactor design, the irradiated graphite waste management has to be faced sooner or later regarding the production of long lived or dose determining radioactive species such as 14C, 3H or 36Cl. The first carbon dioxide cooled, graphite moderated nuclear reactors resulted in a huge quantity of irradiated graphite waste for which the management needs a previous assessment of the radioactive inventory and the radionuclide’s location and speciation. As the detection limits of usual spectroscopic methods are generally not adequate to detect the low concentration levels (<1 ppm) of the radionuclides, we used an indirect approach based on the implantation of 37Cl, to simulate the presence of 36Cl. Our previous studies show that temperature is one of the main factors to be considered regarding the structural evolution of nuclear graphite and chlorine mobility during reactor operation. However, thermal release of chlorine cannot be solely responsible for the depletion of the 36Cl inventory. We propose in this paper to study the impact of irradiation and its synergetic effects with temperature on chlorine release. Indeed, the collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic collisions. However, a small part of the recoil carbon atom energy is also transferred to the lattice through electronic excitation. This paper aims at elucidating the effects of the different irradiation regimes (ballistic and electronic) using ion irradiation, on the mobility of implanted 37Cl, taking into account the initial disorder level of the nuclear graphite

  3. Ion irradiation of 37Cl implanted nuclear graphite: Effect of the energy deposition on the chlorine behavior and consequences for the mobility of 36Cl in irradiated graphite

    Toulhoat, N.; Moncoffre, N.; Bérerd, N.; Pipon, Y.; Blondel, A.; Galy, N.; Sainsot, P.; Rouzaud, J.-N.; Deldicque, D.

    2015-09-01

    Graphite is used in many types of nuclear reactors due to its ability to slow down fast neutrons without capturing them. Whatever the reactor design, the irradiated graphite waste management has to be faced sooner or later regarding the production of long lived or dose determining radioactive species such as 14C, 3H or 36Cl. The first carbon dioxide cooled, graphite moderated nuclear reactors resulted in a huge quantity of irradiated graphite waste for which the management needs a previous assessment of the radioactive inventory and the radionuclide's location and speciation. As the detection limits of usual spectroscopic methods are generally not adequate to detect the low concentration levels (<1 ppm) of the radionuclides, we used an indirect approach based on the implantation of 37Cl, to simulate the presence of 36Cl. Our previous studies show that temperature is one of the main factors to be considered regarding the structural evolution of nuclear graphite and chlorine mobility during reactor operation. However, thermal release of chlorine cannot be solely responsible for the depletion of the 36Cl inventory. We propose in this paper to study the impact of irradiation and its synergetic effects with temperature on chlorine release. Indeed, the collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic collisions. However, a small part of the recoil carbon atom energy is also transferred to the lattice through electronic excitation. This paper aims at elucidating the effects of the different irradiation regimes (ballistic and electronic) using ion irradiation, on the mobility of implanted 37Cl, taking into account the initial disorder level of the nuclear graphite.

  4. 36Cl measurements in Hiroshima granite samples as part of an international intercomparison study. Results from the Munich group.

    Huber, T; Rühm, W; Hoshi, M; Egbert, S D; Nolte, E

    2003-04-01

    Within the effort to resolve the so-called Hiroshima neutron discrepancy, an international intercomparison study has been carried out on granite samples from Hiroshima, with participating institutions from Japan, the US, and Germany. (36)Cl and (152)Eu produced in these samples by thermal neutrons from the A-bomb explosion were assessed independently by means of different techniques. At the Maier-Leibnitz-Laboratory near Munich, Germany, (36)Cl concentrations were measured by accelerator mass spectrometry. Measured (36)Cl/Cl ratios ranged from 1,670 x 10(-13) (at a distance of 146 m from the hypocenter) to 2.2 x 10(-13) (at a distance of 1,163 m from the hypocenter). One granite sample not exposed to A-bomb neutrons was measured as a control, and a (36)Cl/Cl ratio of 2.6 x 10(-13) was obtained. On average, our experimental results are 20-30% lower than those provided by model calculations based on the dosimetry system DS86. The results presented here do not support previous assessments of (36)Cl, (60)Co, and (152)Eu which had suggested much larger thermal neutron fluences than those calculated on the basis of DS86 for distances from the hypocenter of more than 1,000 m. PMID:12684827

  5. Transfer of 45Ca and 36Cl at the blood-nerve barrier of the sciatic nerve in rats fed low or high calcium diets

    Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 ± 0.04 and 0.40 ± 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). The authors results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways

  6. Distribution of 36Cl in the Yoro River Basin, Central Japan, and Its Relation to the Residence Time of the Regional Groundwater Flow System

    Akihiko Kondoh

    2011-01-01

    Full Text Available This study investigates the potential of 36Cl in tracing young groundwater with residence times of up to ~50 years. Groundwater samples were obtained from 16 irrigation wells in paddy fields located within an upland–lowland system in the Yoro River basin, Central Japan. The 36Cl/Cl ratios were in the range of 17 to 362 × 10−15. Among the samples with higher Cl− concentrations (>10 mg/L, two samples showed high nitrate concentrations as well (>30 mg/L. Except for these samples, the distribution of 36Cl in groundwater was essentially consistent with previous tritium concentration data measured in 1982 and 1994, considering the time that has elapsed since these earlier measurements were performed. 36Cl/Cl values were less than 30 × 10−15 in lowland areas, with higher values in and around upland areas. The results indicate longer residence times in the regional groundwater flow system (>50 years than those estimated in previous studies, especially in the area west of the Yoro River. The results demonstrate the ability of 36Cl to trace young groundwater flow, particularly because high values of bomb-derived 36Cl/Cl are easily discriminated from pre-bomb water with low 36Cl/Cl values. Because of its very long half-life (3.01 × 105 years, 36Cl remains even after tritium is no longer available.

  7. Deriving earthquake history of the Knidos Fault Zone, SW Turkey, using cosmogenic 36Cl surface exposure dating of the fault scarp.

    Yildirim, Cengiz; Ersen Aksoy, Murat; Akif Sarikaya, Mehmet; Tuysuz, Okan; Genc, S. Can; Ertekin Doksanalti, Mustafa; Sahin, Sefa; Benedetti, Lucilla; Tesson, Jim; Aster Team

    2016-04-01

    Formation of bedrock fault scarps in extensional provinces is a result of large and successive earthquakes that ruptured the surface several times. Extraction of seismic history of such faults is critical to understand the recurrence intervals and the magnitude of paleo-earthquakes and to better constrain the regional seismic hazard. Knidos on the Datca Peninsula (SW Turkey) is one of the largest cities of the antique times and sits on a terraced hill slope formed by en-echelon W-SW oriented normal faults. The Datça Peninsula constitutes the southern boundary of the Gulf of Gökova, one of the largest grabens developed on the southernmost part of the Western Anatolian Extensional Province. Our investigation relies on cosmogenic 36Cl surface exposure dating of limestone faults scarps. This method is a powerful tool to reconstruct the seismic history of normal faults (e.g. Schlagenhauf et al 2010, Benedetti et al. 2013). We focus on one of the most prominent fault scarp (hereinafter Mezarlık Fault) of the Knidos fault zone cutting through the antique Knidos city. We collected 128 pieces of tablet size (10x20cm) 3-cm thick samples along the fault dip and opened 4 conventional paleoseismic trenches at the base of the fault scarp. Our 36Cl concentration profile indicates that 3 to 4 seismic events ruptured the Mezarlık Fault since Last Glacial Maximum (LGM). The results from the paleoseismic trenching are also compatible with 36Cl results, indicating 3 or 4 seismic events that disturbed the colluvium deposited at the base of the scarp. Here we will present implications for the seismic history and the derived slip-rate of the Mezarlık Fault based on those results. This project is supported by The Scientific and Technological Research Council of Turkey (TUBITAK, Grant number: 113Y436) and it was conducted with the Decision of the Council of Ministers with No. 2013/5387 on the date 30.09.2013 and was done with the permission of Knidos Presidency of excavation in

  8. Initial results from isotope dilution for Cl and 36Cl measurements at the PSI/ETH Zurich AMS facility

    The first results of our use of isotope dilution for determining total Cl and 36Cl in the same rock sample material are presented here. Tests with a dilution series of hypothetical rock Cl concentrations between 5 and 200 ppm verified that our accelerator set-up is appropriate for the low-energy side 37Cl/35Cl measurements. Results from limestone and dolomite samples from the Flims rockslide (Switzerland) indicate the extraction methods described here yield highly reproducible total Cl and 36Cl concentrations with excellent precision to very low values. Replicate measurements suggest that the rocks we are analyzing from the Flims rockslide are closed to uptake or loss of the isotopes of Cl

  9. In-situ buildup of cosmogenic isotopes at the earth`s surface: measurement of erosion rates and exposure times

    Fifield, L.K.; Allan, G.L.; Stone, J.O.H.; Evans, J.M.; Cresswell, R.G.; Ophel, T.R. [Australian National Univ., Canberra, ACT (Australia)

    1993-12-31

    Cosmic rays produce a number of nuclides in rocks that can be used to determine the geomorphic history of surfaces. The most useful are the radioactive isotopes {sup 10}Be (t{sub 1/2} = 1.5Ma), {sup 26}Al (0.7Ma) and {sup 36}Cl (0.3Ma). Within the top 2m of the surface, these are produced principally by fast neutrons. At greater depths, production is dominated by the capture of negative muons. Measurements of a single nuclide produced in situ can be used to determine total exposure times or erosion rates. The use of multiple nuclides with different half-lives makes it possible to determine more complex histories, such as exposures interrupted by periods of burial. At the ANU, all three of the isotopes above are being used to study a variety of problems in geomorphology and paleoclimatology, although to date, most of the work has concentrated on {sup 36}Cl. The accumulation of cosmogenic {sup 36}Cl in calcite (CaCO{sub 3}) provides a means of measuring erosion rates on limestone surfaces. Sensitivity is achieved over a wide range of erosion rates due to the high production rate of {sup 36}Cl in calcite (typically greater than 30 atoms/g/yr) and a detection limit of ca. 5000 atoms/g attainable with the ANU AMS system. The method is simplified by the predominance of Ca reactions (principally spallation) over other sources of {sup 36}Cl in calcite, and the ease of sample preparation. This presentation discuss the results of measurements of {sup 36}Cl in calcite from limestone samples from Australia and Papua New Guinea. Erosion rates derived from these measurements range from 3 microns per year (Australia) to over 200 microns per year in the New Guinea highlands. 3 refs.

  10. Evidence from cosmic-ray exposure dating based on 36Cl for the pre-Minoan caldera on Santorini, Greece

    Athanassas, Constantin; Bourlès, Didier; Braucher, Regis; Druitt, Tim; Nomikou, Paraskevi; Léanni, Laetitia

    2016-04-01

    The physiography of Santorini prior to the Minoan (Late Bronze Age) eruption (17th century BCE) is of great archaeological interest, given the importance of Santorini as a commercial centre and port in the Minoan empire. However, the paleogeography of the pre-Minoan caldera has been a point of controversy: Heiken and McCoy (1984) advocated the existence, in the southern part of the present-day caldera, of a pre-existing caldera formed during the 172 ka Lower Pumice eruption, whereas Druitt and Francaviglia (1992), based on the presence of in situ plinian pumice from the Minoan eruption adhering to the modern cliff, conceived the pre-Minoan (22 ka) caldera as having occupied much of the northern basin of the present-day caldera. With the goal of settling the debate we performed cosmic ray exposure dating employing in situ-produced cosmogenic 36Cl to date different generations of caldera cliffs at Santorini, and hence to identify those cliffs predating the Minoan eruption. Our methodology involved the determination of the in situ-produced cosmogenic 36Cl in basaltic and andesitic rocks cropping out in the cliffs. The samples returned 36Cl CRE ages consistent with previously published field mapping of cliff populations based on geomorphological and stratigraphic arguments (Druitt and Francaviglia 1992), suggesting that much of the present cliff line of northern Santorini predated the Minoan eruption, or was superficially modified by landslips and rockfalls during that eruption. The 36Cl CRE ages enable us to better define the paleogeography of the pre-Minoan caldera. References [1] Druitt, T. H. and Francaviglia, V.1992. Caldera formation on Santorini and the physiography of the islands in the Late Bronze Age. Bulletin of Volcanology 54, 484-493. [2] Heiken G and McCoy F (1984) Caldera development during the Minoan eruption, Thira, Cyclades, Greece. Journal of Geophysical Research: 89 (B10), 8841-8862.

  11. Methodological study on exposure date of Tiankeng by AMS measurement of in situ produced cosmogenic {sup 36}Cl

    Dong Kejun [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Li Shizhuo [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); CNNC China North Nuclear Fuel Company Ltd., Baotou 014035 (China); He Ming [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Sasa, Kimikazu [Tandem Accelerator Complex, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Matsushi, Yuki [Disaster Prevention Research Institute, Kyoto University (Japan); Huang Baojian [Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004 (China); Ruan Xiangdong; Guan Yongjing [College of Physics Science and Technology, Guangxi University, Nanning 530004 (China); Takahashi, Tsutomu [Tandem Accelerator Complex, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Sueki, Keisuke [Graduate School of Pure and Applied Sciences, University of Tsukuba (Japan); Li Chaoli; Wu Shaoyong [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Wang Xianggao [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004 (China); Shen Hongtao [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); College of Physics and Technology, Guangxi Normal University, Guilin 541004 (China); Nagashima, Yasuo [Tandem Accelerator Complex, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Jiang Shan, E-mail: jiangs@ciae.ac.cn [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China)

    2013-01-15

    Tiankeng is a typical Karst relief of the late Quaternary Period. Studies on the exposure ages of Tiankeng are very important in geographical research to elucidate the formation condition, the developing process, and the features of biological species. {sup 36}Cl on the surface layer of the rupture cross-section of Tiankeng is largely produced by cosmogenic high-energy neutron induced reactions {sup 40}Ca(n, {alpha}p) and {sup 39}K(n, {alpha}), and has accumulated since the formation of the Tiankeng. Low-energy neutron reaction {sup 35}Cl(n, {gamma}) contributes a small portion of {sup 36}Cl. In this work, the concentration of the cosmogenic {sup 36}Cl in rock samples taken from Dashiwei Tiankeng, Leye County, Guangxi Zhuang Autonomous Region, China, was measured jointly by Accelerator Mass Spectrometry (AMS) laboratories of CIAE and University of Tsukuba in an effort to estimate the formation time (or exposure age) of the Tiankeng. The results show that the exposure time of Da Shiwei Tiankeng is about 26 {+-} 9.6 ka (without erosion correction). The sampling strategy and procedures, experimental set-up, and preliminary results will be presented in detail.

  12. "Groundwater ages" of the Lake Chad multi-layer aquifers system inferred from 14C and 36Cl data

    Bouchez, Camille; Deschamps, Pierre; Goncalves, Julio; Hamelin, Bruno; Seidel, Jean-Luc; Doumnang, Jean-Claude

    2014-05-01

    Assessment of recharge, paleo-recharge and groundwater residence time of aquifer systems of the Sahel is pivotal for a sustainable management of this vulnerable resource. Due to its stratified aquifer system, the Lake Chad Basin (LCB) offers the opportunity to assess recharge processes over time and to link climate and hydrology in the Sahel. Located in north-central Africa at the fringe between the Sahel and the Sahara, the lake Chad basin (LCB) is an endorheic basin of 2,5.106 km2. With a monsoon climate, the majority of the rainfall occurs in the southern one third of the basin, the Chari/Logone River system transporting about 90% of the runoff generated within the drainage basin. A complex multi-layer aquifer system is located in the central part of the LCB. The Quaternary unconfined aquifer, covering 500 000 km2, is characterized by the occurrence of poorly understood piezometric depressions. Artesian groundwaters are found in the Plio-Pleistocene lacustrine and deltaic sedimentary aquifers (early Pliocene and Continental Terminal). The present-day lake is in hydraulic contact with the Quaternary Aquifer, but during past megalake phases, most of the Quaternary aquifer was submerged and may experience major recharge events. To identify active recharge area and assess groundwater dynamics, one hundred surface and groundwater samples of all layers have been collected over the southern part of the LCB. Major and trace elements have been analyzed. Measurements of 36Cl have been carried out at CEREGE, on the French 5 MV AMS National Facility ASTER and 14C activities have been analyzed for 17 samples on the French AMS ARTEMIS. Additionally, the stable isotopic composition was measured on the artesian aquifer samples. In the Quaternary aquifer, results show a large scatter with waters having very different isotopic and geochemical signature. In its southern part and in the vicinity of the surface waters, groundwaters are predominantly Ca-Mg-HCO3 type waters with very

  13. Tectonic Geomorphology and 36Cl geochronology of the Camardi Alluvial Fan Complex, Central Anatolia: Implications for Neotectonic activity of the Central Anatolian Fault Zone (CAFZ)

    Higgins, M.; Schoenbohm, L. M.; Gosse, J. C.

    2013-12-01

    Situated between an extensional province to the west and younger, compressional forces to the east, the significance of internal deformation within Central Anatolia, and particularly the Central Anatolian Fault Zone, remains poorly understood. The CAFZ, which records approximately 70+/- 10km of Cenozoic sinistral displacement, was initially described as an active, NE trending, 700km long, major intra-plate shear zone. However, the Cenozoic evolution of the CAFZ and its relevance to the modern tectonic setting of Anatolia are the subject of debate, and the kinematics, geometry and activity levels of the CAFZ remain both poorly documented and understood. The aim of this study is to constrain the extrusion related, neotectonic portion of this total displacement using methods unavailable to previous studies of the area: Terrestrial Cosmogenic Nuclide (TCN) geochronology and newly acquired high-resolution satellite imagery. Focusing on a tectonically offset alluvial fan complex, we apply In situ TCN 36Cl exposure dating to produce new geochronologically constrained quaternary slip rates for the southern, Ecemis Segment of the CAFZ. A combination of field observations, high precision GPS based fault scarp profiles and mapping on high-resolution satellite images are used to document offset geomorphic markers including: deflected streams, terrace edges and shutter ridges. These features show sinistral and normal displacement of 60 and 18 m respectively in the older alluvial surface. Determining the ages of this faulted surface, as well as a younger un-deformed alluvial surface using TCN, will yield a minimum quaternary slip-rate. Additionally, morphological characteristics of 25 drainage basins along the Ecemis Fault are determined using Digital Elevation Model (DEM)data. Key geomorphic indices include: hypsometric integral, basin asymmetry and the valley width-to-height ratio (Vf). The results suggest the morphology of these drainage basins is influenced by the recent

  14. Toward determining the uncertainties associated with the seismic histories retrieved from in situ 36Cl cosmogenic nuclide fault scarp dating: model reappraisal.

    Tesson, Jim; Benedetti, Lucilla

    2016-04-01

    How the past seismic activity of faults has varied over the last 20 ky is a crucial information for seismic hazard assessment and for the understanding of fault-interaction processes. Chlorine 36 in situ produced cosmogenic nuclide is increasingly used to retrieve past earthquakes histories on seismically exhumed limestone normal fault-scarps. Schlagenhauf et al. in 2010 developed a modeling code with a forward approach enabling the test of scenarii generated with a priori constraints (number of events, age and slip of events and pre-exposure time). The main shortcomings of this forward approach were the limited number of testable scenarii and the difficulty to derive the associated uncertainties. We present here a reappraisal methodology with an inverse approach using an optimization algorithm. This modelling approach enables 1-exploring the parameter space (age and slip of events), 2-finding the best scenario without a priori constraints and 3-precisely quantifying the associated uncertainties by determining the range of plausible models. Through a series of synthetic tests, we observed that the algorithm revealed a great capacity to constrain event slips and ages in a short computational time (several hours) with an accuracy that can reach 0.1 ky and 0.5 m for the age and slip of exhumation event, respectively. We also explore the influence of the pre-exposure history (amount of 36Cl accumulated when the sampled fault-plane was still buried under the colluvial wedge) and show that it has an important impact on the generated scenarii. This new modeling also allows now to accurately determining this parameter. Finally, the results show that any given [36Cl] profile results in a unique exhumation solution. We then apply this new model to the Magnola fault (Italy) dataset (Schlgenhauf et al. 2011). In agreement the previously published results, our model also results in 3 intense periods of seismic activity. However, the contribution of the pre-exposure history is

  15. Ion irradiation of {sup 37}Cl implanted nuclear graphite: Effect of the energy deposition on the chlorine behavior and consequences for the mobility of {sup 36}Cl in irradiated graphite

    Toulhoat, N., E-mail: nelly.toulhoat@univ-lyon1.fr [Université de Lyon, Université Lyon 1, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon (IPNL) (France); CEA/DEN, Centre de Saclay (France); Moncoffre, N. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon (IPNL) (France); Bérerd, N.; Pipon, Y. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon (IPNL) (France); Université de Lyon, Université Lyon, IUT Lyon-1 département chimie (France); Blondel, A. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon (IPNL) (France); Andra, Châtenay-Malabry (France); Galy, N. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon (IPNL) (France); Sainsot, P. [Université de Lyon, Université Lyon 1, LaMCoS, INSA-Lyon, CNRS UMR5259 (France); Rouzaud, J.-N.; Deldicque, D. [Laboratoire de Géologie de l’Ecole Normale Supérieure (ENS), Paris, UMR CNRS-ENS 8538 (France)

    2015-09-15

    Graphite is used in many types of nuclear reactors due to its ability to slow down fast neutrons without capturing them. Whatever the reactor design, the irradiated graphite waste management has to be faced sooner or later regarding the production of long lived or dose determining radioactive species such as {sup 14}C, {sup 3}H or {sup 36}Cl. The first carbon dioxide cooled, graphite moderated nuclear reactors resulted in a huge quantity of irradiated graphite waste for which the management needs a previous assessment of the radioactive inventory and the radionuclide’s location and speciation. As the detection limits of usual spectroscopic methods are generally not adequate to detect the low concentration levels (<1 ppm) of the radionuclides, we used an indirect approach based on the implantation of {sup 37}Cl, to simulate the presence of {sup 36}Cl. Our previous studies show that temperature is one of the main factors to be considered regarding the structural evolution of nuclear graphite and chlorine mobility during reactor operation. However, thermal release of chlorine cannot be solely responsible for the depletion of the {sup 36}Cl inventory. We propose in this paper to study the impact of irradiation and its synergetic effects with temperature on chlorine release. Indeed, the collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic collisions. However, a small part of the recoil carbon atom energy is also transferred to the lattice through electronic excitation. This paper aims at elucidating the effects of the different irradiation regimes (ballistic and electronic) using ion irradiation, on the mobility of implanted {sup 37}Cl, taking into account the initial disorder level of the nuclear graphite.

  16. The economic production lot size model with several production rates

    Larsen, Christian

    should be chosen in the interval between the demand rate and the production rate, which minimize unit production costs, and should be used in an increasing order. Then, given the production rates, we derive closed form solutions for the optimal runtimes as well as the minimum average cost. Finally we......We study an extension of the economic production lot size model, where more than one production rate can be used during a cycle. The production rates and their corresponding runtimes are decision variables. We decompose the problem into two subproblems. First, we show that all production rates...... derive a near-optimal solution to the general problem....

  17. TISSUE RESIDUES, METABOLISM, AND EXCRETION OF NA[36CL]O3 IN RATS

    A novel pre-harvest technology that reduces certain pathogenic bacteria in the gastrointestinal tracts of food animals involves feeding an experimental sodium chlorate-containing product (ECP) to animals 24-72 h prior to slaughter. In order to determine the metabolism and disposition of the active ...

  18. Biological transfer and loss of 36Cl-labeled DDT in an old-field ecosystem

    An enclosed 10-acre old-field plot treated in June 1969, with chlorine-36 labeled DDT was sampled each year from 1969 through 1974 to monitor the fate of the insecticide in the soil and biota. In order to provide data on compartmentalization of DDT in the vegetation, invertebrates and vertebrates inhabiting the plot, sampling was carried out to estimate both body burdens of DDT and biomass of populations. Another aspect of this study, the determination of rates of accumulation of residues by invertebrates and vertebrates, has been reported previously (Forsyth and Peterle 1973; Forsyth et al. 1975; Peterle 1975). This report describes (a) temporal patterns of DDT residues in soil and biota from 1969 through 1974 and (b) quantities of DDT held in the soil and biotic compartments of the ecosystem. Part II of the report is concerned with translocation and accumulation of14C-DDT

  19. Behavior of 32P, 35S, 36Cl and 42K in magnesium oxide

    A separation method of 32P from 35S using magnesium oxide as adsorbent of radiophosphorus is described. The behaviour of 32P and 35S, both carrier-free, on magnesium oxide, individually, in dependence of the amount of the adsorbent, of mixing time, of the pH of the loading solution and of potassium chloride concentration, is studied. The separation of the mentioned radioisotopes, using a misture of them, is also analysed. In order to apply this method to the routine production of carrier-free 35S by potassium chloride irradiation, the adsorption behaviour of the chloride and potassium on magnesium oxide using radioactive tracers of these elements, is studied. The separation of 35S from 32P is analyzed by the maximum range of β- particles in aluminum. The absorption curves are presented and compared. (Author)

  20. NESDIS Blended Rain Rate (RR) Products

    National Oceanic and Atmospheric Administration, Department of Commerce — The blended Rain Rate (RR) product is derived from multiple sensors/satellites. The blended products were merged from polar-orbiting and geostationary satellite...

  1. Localization of 45Ca and 36Cl in fruit tissue of apples after post harvest dipping

    Apples of 'Cox's Orange Pippin' and 'Golden Delicious' were post-harvest dipped (2% CaCl2 + 0.3% Keltrol) to study the translocation and deposit of Ca and of Cl in the fruit. Macroautoradiographic studies showed that both ions easily penetrated into the fruit increasingly with time of storage, but that they were distributed differently: After 3 months of storage Ca was found in all parts of the fruit, more pronounced so in the vascular tissue and cortex, contrary to Cl, which mainly accumulated in the cortex tissue. In the area of the calyx and stem end penetration was markedly enhanced. After external application of Ca and other multivalent cations the endogenous fruit Ca was partly translocated into the tissue below. Efflux and exchange experiments with fruit tissue in hypertonic solution showed that 5-10% of the Ca deposited in the cortex after post-harvest dipping was removed within 5 h; however, with addition of EDTA to the solution, more than 80% exchanged. Contrarily, the rate of Cl efflux and that of monovalent cations (K,Na) was only half the amount, independent whether the complexing agent was added to the solution or not. Likewise 64-72% of the Ca deposited after natural transport into the fruit, could be exchanged. After supply of 1 mM 45CaCl2 in hypertonic solution substantial amounts of Ca were absorbed by the fruit tissue, but even after an exchange period with EDTA a remarkable portion was retained. The investigations underline the importance of the high cation binding capacity of the fruit tissue in the region of the membrane and cell wall with respect to the function of Ca. Furthermore, it was shown that the Ca companion ion, Cl, has to be included into the considerations. (orig./MG)

  2. A high-density ammonia storage/delivery system based on Mg(NH3)6Cl2 for SCR-DeNOx in vehicles

    Elmøe, Tobias Dokkedal; Sørensen, Rasmus Zink; Quaade, Ulrich;

    2006-01-01

    In this paper, we present a new benchmark for the automobile selective catalytic reduction of NO(x): Mg(NH(3))(6)Cl(2). This solid complex releases ammonia upon heating and can be compacted into a dense shape which is both easy to handle and safe. Furthermore, the material has a high volumetric a...

  3. Eu2+ and Dy3+ codoped (Ca,Sr)7(SiO3)6Cl2 highly efficient yellow phosphor

    刘冯新; 房永征; 张娜; 候京山; 张灵彦; 于圣洁; 刘淑培

    2014-01-01

    Eu2+ and Dy3+ codoped (Ca,Sr)7(SiO3)6Cl2 yellow phosphors were successfully synthesized by self-flux method. The struc-ture, morphology and photoluminescence properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectra. The as-prepared phosphor showed a broad emission spectrum centered at 550 nm for Eu2+ single-doped phosphor, while located at 548-544 nm for the Eu2+, Dy3+ codoped samples under excitation at 380 nm light. The emis-sion intensity was greatly improved when Dy3+ was doped into the (Ca,Sr)7(SiO3)6Cl2:Eu2+ system. The composition-optimized sam-ple with 3 mol.% of Dy3+ and constant 10 mol.% of Eu2+ exhibited a 220% PL enhancement compared to the phosphor with 10 mol.% Eu2+ single-doped. Meanwhile, it was found that the quantum efficiency of phosphor namely (Ca,Sr)7(SiO3)6Cl2:3 mol.% Dy3+, 10 mol.% Eu2+ could get up to 24.6%. The synthesized yellow-emitting (Ca,Sr)7(SiO3)6Cl2:Dy3+,Eu2+ is a promising candidate as high-efficiency yellow phosphor for NUV-excited white LEDs.

  4. 30 CFR 250.1632 - Production rates.

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Production rates. 250.1632 Section 250.1632 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Sulphur Operations § 250.1632 Production rates. Each...

  5. Interest Rate Derivatives : An analysis of interest rate hybrid products

    Chimanga, Taurai

    2011-01-01

    The globilisation phenomena is causing an increasing interaction between different markets and sectors. This has led to the evolution of derivative instruments from ”single asset” instruments to complex derivatives that have underlying assets from different markets, sectors and sub-sectors. These are the so-called hybrid products that have multi-assets as underlying instruments. This article focuses on interest rate hybrid products. In this article an analysis of the application of stochastic...

  6. Methods of Radioactivity Measurement for Beta Emitter Radionuclides of 14C, 36Cl and 90Sr in Area Geometric Using 2π Proportional Counter

    The radioactivity measurement of beta emitter of 14C, 36Cl and 90Sr in area geometric have been carried out by 2π proportional counter in Center for Technology of Safety and Metrology Radiation-BATAN. The measurement is needed to get standard methods for standardized of beta emitter in area geometric without destructing of the sample. The Measurement is carried out by 2π proportional counter using gas flow system of P10 in order that ionization process to be passed continuously. To prevent damage. the sources covered with very thin foil layer. Detection efficiencies are determined by variation of beta discriminator. The activities of sources are determined by extrapolation methods to 100 % of efficiencies. The results measurements are fairly good by (5954 ± 62) Bq for 14C ; (5175 ± 49) Bq for 36Cl and (1619 ± 23) Bq for 90Sr. (author)

  7. Synthesis of [6-36Cl]chlorouracil, [6-82Br]bromouracil and [6-123I]iodouracil

    Three C-6 radiohalogenated uracil derivatives were prepared by non-isotopic halogen exchange reactions for evaluation as diagnostic radiopharmaceuticals. [6-36Cl]chlorouracil (radiochemical yield 77%, specific activity 5.66 MBq mmol-1) was prepared via calcium [36Cl]chloride exchange on 6-iodouracil, [6-82Br]bromouracil (27%, 68.4 MBq mmol-1) was prepared via ammonium [82Br]bromide exchange on 6-iodouracil and [6-123I]iodouracil (55.4%, 5.41 GBq mmol-1) was prepared via sodium [123I]iodide exchange on 6-chlorouracil. The specific activities and radiochemical yields were dependent upon the halide-ion concentration. (author)

  8. The rock avalanche of the Mt. Peron (Eastern Alps, Italy): new insights from 36Cl exposure dating

    Martin, Silvana; Ivy-ochs, Susan; Alfimov, Vasili; Vockenhuber, %Christof; Surian, Nicola; Campedel, Paolo; Rigo, Manuel; Viganò, Alfio; De Zorzi, Manuel

    2016-04-01

    In the Late Pleistocene, in the southern side of the Eastern Alps (Veneto region, Italy), when the glacier tongues retreated from the end moraine system areas towards the Dolomitic region, large rock avalanches took place. In the Belluno Valley, occupied by the Piave river, the left side is represented by the Belluno Prealps range, corresponding to the northern flank of a km-scale WSW-ENE oriented alpine syncline formed by rocks from Late Triassic to Late Tertiary in age. The Mt. Peron, belonging to this mountain range, shows its southern lower slope covered by debris cones with scattered boulders and its higher slope, corresponding to the scarp, made of vertical rock strata. At the foot of Mt. Peron, at a distance varying from 500 to 4500 m, there is a 4.5 km2 fan like area delimited by a perimeter of about 15 km. This is a hilly area of poortly sorted, chaotic deposits composed of heterogeneous debris, sandy and silty gravels, angular blocks and very large boulders of carbonatic rocks up to 20 m in diameter. The average thickness of the deposit was estimated to be 80 m, with maximum of 120 m. According to previous works, the main event occurred during the first phases of deglaciation, between 17,000 and 15,000 years BP. Popular stories narrate about two legendary villages destroyed by a mass of stones rolling down in the valley. This is confirmed by archeological findings in the Piave valley which indicate the presence of almost one pre-historic settlement dating 40000-20000 years a B.P., (i.e. before the Last Glacial Maximum).. Recent 36Cl exposure dating have yielded historical ages for both the boulders at the foot of the Mt Peron and those located a few km far from the main scarp. According to these exposure ages we can not exclude the hypothesis that earthquakes related to the Venetian faults could have played a key role for triggering of the rock avalanche and that the main gravitational event took place in historical times rather than during the

  9. X-ray Lβ215 emission spectrum of Ru in Ru(NH3)6Cl3

    One of the broader applications of synchrotron radiation has been to EXAFS studies for material structure determination, i.e., for an analysis of x-ray absorption over an extended energy region beyond a core ionization limit. Studies of the near edge structure (XANES) give a different type of information, characteristic of the local symmetry and electronic configuration of the absorbing atom. This type of information is reflected also in the x-ray emission spectra, in particular for transitions involving the valence levels. Examination of the near edge absorption or the emission spectrum does not require an instrument capable of scanning a wide energy range with high counting statistics, as does EXAFS; the needs are rather for good resolution and a reliable calibration of the energy scale. Some of the problems of near edge spectra were particularly evident in our investigation of Ru-Lβ215 emission from Ru(NH3)6Cl3. The Ru-Lβ215 emission was measured with a laboratory Rowland circle x-ray spectrometer with a curved quartz (1010) crystal (radius = 22 inches) in a fixed position appropriate to the energy range, and a position sensitive detector which can be positioned along the Rowland circle. The Ru spectrum was excited mainly by Sn-L/sub α/ primary radiation from a Sn anode in a demountable x-ray tube operating at 13 kV and 120 mA. The resolution of the instrument in this region is 1.5 eV. An accurate calibration of the energy scale was conveniently obtained by measuring a reference x-ray emission line in the same instrumental configuration. In the present case the Pd-L/sub α/ emission line at 2838 eV was used to establish the energy scale. The energy dispersion of the instrument was determined from the Cl-K/sub β/ emission spectrum of CH3Cl between 2810 eV and 2830 eV and Pd-Lα12 and extrapolated to the energy region of the recorded emission spectrum. 6 references, 1 figure

  10. The Production Rate of Natural Tritium

    Craig, Harmon; Lal, Devendra

    2011-01-01

    A detailed evaluation is made of the production rate of natural tritium in the pre-thermonuclear epoch. Deuterium and tritium analyses on the same precipitation samples are used to establish the uncontaminated tritium levels in precipitation sampled before the Castle tests, and the tritium balance is calculated for the North American troposphere. The global mean production rate Q?, calculated from the geochemical inventory, is found to be 0.5 ± 0.3 atoms T/cm2 sec. This value is three ...

  11. Production rate analysis of cold heavy oil production wells

    Liu, X. [China National Offshore Oil Corp., Beijing (China); Zhao, G.; Jin, Y.C. [Regina Univ., SK (Canada)

    2006-07-01

    This study investigated the performance and production rates of cold heavy oil production (CHOP) wells. CHOP is a non-thermal process where sand is produced to stimulate heavy oil primary production. Studies have demonstrated that wormholes are generated during sand production processes, and provide main conduits for fluid flow in reservoirs. Wormholes and foamy oil flow are responsible for the enhancement of oil production rates in CHOP wells. In this study, a comprehensive model was designed to simulate the production rate behaviour of CHOP wells in order to account for the pressure-dependent apparent viscosity of foamy oil and dynamic wormhole growth. Pressure-dependent viscosity was modelled as a pseudo-pressure form, and dynamic wormhole growth was incorporated in terms of modified source functions. A simple relationship for bubble flow was used due to the unclear mechanisms of foamy oil flow. The model was then compared with field test results from typical CHOP wells. Results of the study showed that wormhole growth velocity and dynamic wormhole growth has a significant impact on production rate profiles. The study will be used to determine infill locations and CHOP well spacings in pool developments. 22 refs., 13 figs.

  12. Towards a model for protein production rates

    Dong, J J; Zia, R K P

    2007-01-01

    In the process of translation, ribosomes read the genetic code on an mRNA and assemble the corresponding polypeptide chain. The ribosomes perform discrete directed motion which is well modeled by a totally asymmetric simple exclusion process (TASEP) with open boundaries. Using Monte Carlo simulations and a simple mean-field theory, we discuss the effect of one or two ``bottlenecks'' (i.e., slow codons) on the production rate of the final protein. Confirming and extending previous work by Chou and Lakatos, we find that the location and spacing of the slow codons can affect the production rate quite dramatically. In particular, we observe a novel ``edge'' effect, i.e., an interaction of a single slow codon with the system boundary. We focus in detail on ribosome density profiles and provide a simple explanation for the length scale which controls the range of these interactions.

  13. Towards a Model for Protein Production Rates

    Dong, J. J.; Schmittmann, B.; Zia, R. K. P.

    2007-07-01

    In the process of translation, ribosomes read the genetic code on an mRNA and assemble the corresponding polypeptide chain. The ribosomes perform discrete directed motion which is well modeled by a totally asymmetric simple exclusion process (TASEP) with open boundaries. Using Monte Carlo simulations and a simple mean-field theory, we discuss the effect of one or two "bottlenecks" (i.e., slow codons) on the production rate of the final protein. Confirming and extending previous work by Chou and Lakatos, we find that the location and spacing of the slow codons can affect the production rate quite dramatically. In particular, we observe a novel "edge" effect, i.e., an interaction of a single slow codon with the system boundary. We focus in detail on ribosome density profiles and provide a simple explanation for the length scale which controls the range of these interactions.

  14. Seismic slip history of the Pizzalto fault (central Apennines, Italy) using in situ-produced 36Cl cosmic ray exposure dating and rare earth element concentrations

    Tesson, J.; Pace, B.; Benedetti, L.; Visini, F.; Delli Rocioli, M.; Arnold, M.; Aumaître, G.; Bourlès, D. L.; Keddadouche, K.

    2016-03-01

    Morphological and geological observations reveal that most Apenninic faults are highly segmented and that the majority of the fault segments are less than 10 km long. Although these faults have undergone numerous paleoseismological investigations, quantitative data remain crucially lacking for a large number of fault segments. Because such data are essential to understanding how these faults have ruptured and interacted in the past and how they might behave in the future, we investigated the Holocene seismic history of the Pizzalto normal fault, a 13 km long fault segment belonging to the Pizzalto-Rotella-Aremogna fault system in the Apennines. We collected 44 samples from the Pizzalto fault plane exhumed during the Holocene and analyzed the 36Cl and rare earth element (REE) contents. Together, the 36Cl and REE concentrations show that at least six events have exhumed 4.4 m of the fault scarp between 3 and 1 ka, with slip per event values ranging from 0.3 to 1.2 m. No major events have been detected over the last 1 kyr. The Rotella-Aremogna-Pizzalto fault system has a clustered earthquake behavior with a mean recurrence time of 1.2 kyr and a low to moderate probability (ranging from 4% to 26%) of earthquake occurrence over the next 50 years.

  15. Diffusion of HTO, 36Cl-, 125I- and 22Na+ in Opalinus Clay: Effect of Confining Pressure, Sample Orientation, Sample Depth and Temperature

    Effective diffusion coefficients (De), rock capacity factors (α) and diffusion-accessible porosities (ε) were measured using the through-diffusion technique. Transport (diffusion) was measured both perpendicular and parallel to the bedding. Special cells that allowed the application of an axial confining pressure were designed. The pressures applied ranged from 1 to 5 MPa for Mont Terri samples and between 4 and 15 MPa for Benken samples, the upper values representing the in-situ confining pressure at both locations. The test solutions used in the experiments were synthetic Opalinus Clay pore water, which has Na and Cl as main components (Mont Terri: I = 0.39 M; Benken: I = 0.20 M). Pressure only had a small effect on the value of the effective diffusion coefficients. In the case of Mont Terri samples, increasing the pressure from 1 to 5 MPa resulted in a decrease of the effective diffusion coefficient of 20% for HTO, 27% for 36Cl-, 29% for 125I- and 17 % for 22Na+. In the case of Benken samples, increasing the pressure from 4 to 15 MPa resulted in a decrease of De of 17% for HTO, 22% for 36Cl-, 32% for 125I- and 17 % for 22Na+. Moreover, the effective diffusion coefficients for for 36Cl-are smaller than for HTO, which is consistent with an effect arising from anion exclusion. This ion exclusion effect is smaller in samples from Mont Terri than in samples from Benken, which can be explained by the higher ionic strength of the Mont Terri water used in the experiments. The diffusion of 22Na+ is similar to that of HTO in the case of Mont Terri OPA. For Benken OPA, the De value of 22Na+ is a factor of 2 higher than that of HTO. This last observation cannot be explained so far but is comparable to experimental data from ANDRA (1999) on Callovo-Oxfordian claystones from the Meuse/Haute Same site. 125I- is retarded with respect to 36Cl-. This is caused by a weak sorption of 125I- on the Opalinus Clay. The distribution coefficients, calculated from the rock capacity

  16. ATMS Snowfall Rate Product and Its Applications

    Meng, H.; Kongoli, C.; Dong, J.; Wang, N. Y.; Ferraro, R. R.; Zavodsky, B.; Banghua Yan, B.

    2015-12-01

    A snowfall rate (SFR) algorithm has been developed for the Advanced Technology Microwave Sounder (ATMS) aboard S-NPP and future JPSS satellites. The product is based on the NOAA/NESDIS operational Microwave Humidity Sounder (MHS) SFR but with several key advancements. The algorithm has benefited from continuous development to improve accuracy and snowfall detection efficiency. The enhancements also expand the applicable temperature range for the algorithm and allow significantly more snowfall to be detected than the operational SFR. Another major improvement is the drastically reduced product latency by using Direct Broadcast (DB) data. The new developments have also been implemented in the MHS SFR to ensure product consistency across satellites. Currently, there are five satellites that carry either ATMS or MHS: S-NPP, NOAA-18/-19 and Metop-A/-B. The combined satellites deliver up to ten SFR estimates a day at any location over land in mid-latitudes. The product provides much needed winter precipitation estimates for applications such as weather forecasting and hydrology. Both ATMS and MHS SFR serve as input to a global precipitation analysis product, the NOAA/NCEP CMORPH-Snow. SFR is the sole satellite-based snowfall estimates in the blended product. In addition, ATMS and MHS SFR was assessed at several NWS Weather Forecast Offices (WFOs) and NESDIS/Satellite Analysis Branch (SAB) for its operational values in winter 2015. This is a joint effort among NASA/SPoRT, NOAA/NESDIS, University of Maryland/CICS, and the WFOs. The feedback from the assessment indicated that SFR provides useful information for snowfall forecast. It is especially valuable for areas with poor radar coverage and ground observations. The feedback also identified some limitations of the product such as inadequate detection of shallow snowfall. The algorithm developers will continue to improve product quality as well as developing SFR for new microwave sensors and over ocean in a project

  17. Translocation of 125I, 75Se and 36Cl to edible parts of radish, potato and green bean following wet foliar contamination under field conditions

    Specific translocation factor values (ftr) for 129I, 79Se and 36Cl following foliar transfer are still missing from the IAEA reference databases. The translocation of the short-lived isotopes, 125I, 75Se, and 36Cl, to radish, potato and green bean edible parts was measured under field conditions following acute and chronic wet foliar contamination at various plant growth stages in the absence of leaching caused by rain. The translocation factors obtained for 125I ranged from 0.8 to 2.6% for radish, from 0.1 to 2.3% for potato and from 0.1 to 2.6% for bean. The translocation factors obtained for 75Se ranged from 6.3 to 21% for radish, from 1.6 to 32.6% for potato and from 7.7 to 22.8% for bean (values similar to Cs or even higher). The translocation factors obtained for 36Cl were close to those for 75Se and ranged from 4.3 to 28.8% for radish, from 0.5 to 31.5% for potato and from 4.3 to 16.3% for bean. Iodide showed the lowest apparent mobility because of its preferential fixation in or on the leaves and a significant amount was probably volatilized. Selenite internal transfer was significant and possibly followed the sulfur metabolic pathway. Chloride was very mobile and quickly diffused throughout the plant. The translocation factors varied with the growth stage and depended on the development state of the edible tissue and its associated sink strength for nutrients and assimilates. For radish, translocation was high during the early vegetative stages. For potato, wheat and bean, a major peak in translocation was seen during the flowering growth stage and the concomitant growth of potato tubers. An additive effect of successive contamination events on translocated elements was shown in radish but not in bean and potato. The highest translocation value obtained for an acute contamination event was shown to be an adequate, conservative indicator of chronic contamination in absence of specific values. Due to the absence of rain leaching during the experiment this

  18. EFFECT OF SODIUM [36CL]CHLORATE DOSE ON TOTAL RADIOACTIVE RESIDUES AND RESIDUES OF PARENT CHLORATE IN GROWING SWINE

    An experimental chlorate-based product has shown to be efficacious in eliminating economically important, Gram-negative human pathogens in the gastrointestinal tracts of food animals. Prior to the commercial marketing of such a product, the magnitude and chemical nature of residues remaining in edib...

  19. Mathematical Modeling of Product Rating: Sufficiency, Misbehavior and Aggregation Rules

    Xie, Hong; Lui, John C. S.

    2013-01-01

    Many web services like eBay, Tripadvisor, Epinions, etc, provide historical product ratings so that users can evaluate the quality of products. Product ratings are important since they affect how well a product will be adopted by the market. The challenge is that we only have {\\em "partial information"} on these ratings: Each user provides ratings to only a "{\\em small subset of products}". Under this partial information setting, we explore a number of fundamental questions: What is the "{\\em...

  20. Fuzzy production planning models for an unreliable production system with fuzzy production rate and stochastic/fuzzy demand rate

    K. A. Halim

    2011-01-01

    Full Text Available In this article, we consider a single-unit unreliable production system which produces a single item. During a production run, the production process may shift from the in-control state to the out-of-control state at any random time when it produces some defective items. The defective item production rate is assumed to be imprecise and is characterized by a trapezoidal fuzzy number. The production rate is proportional to the demand rate where the proportionality constant is taken to be a fuzzy number. Two production planning models are developed on the basis of fuzzy and stochastic demand patterns. The expected cost per unit time in the fuzzy sense is derived in each model and defuzzified by using the graded mean integration representation method. Numerical examples are provided to illustrate the optimal results of the proposed fuzzy models.

  1. ESTIMATING TRUCK RATES FOR REFRIGERATED FOOD PRODUCTS

    Ward, J. B.; Farris, Donald E.

    1990-01-01

    Food companies and analysts often need transportation rate data to explore market opportunities. In some cases, it may not be practical or necessary to obtain actual rates for all routes under consideration. This study provides analysis of truck rate patterns and alternative rate-estimating equations. The original objective was to provide shipping cost estimates for a national beef-marketing model involving 30 regions of the United States. The data set is 254 rates for refrigerated shipments ...

  2. Biological transfer and loss of /sup 36/Cl-labeled DDT in an old-field ecosystem

    Peterle, T.J.

    1979-04-20

    An enclosed 10-acre old-field plot treated in June 1969, with chlorine-36 labeled DDT was sampled each year from 1969 through 1974 to monitor the fate of the insecticide in the soil and biota. In order to provide data on compartmentalization of DDT in the vegetation, invertebrates and vertebrates inhabiting the plot, sampling was carried out to estimate both body burdens of DDT and biomass of populations. Another aspect of this study, the determination of rates of accumulation of residues by invertebrates and vertebrates, has been reported previously (Forsyth and Peterle 1973; Forsyth et al. 1975; Peterle 1975). This report describes (a) temporal patterns of DDT residues in soil and biota from 1969 through 1974 and (b) quantities of DDT held in the soil and biotic compartments of the ecosystem. Part II of the report is concerned with translocation and accumulation of/sup 14/C-DDT.

  3. Productive Government Spending, Welfare and Exchange Rate Dynamics

    Juha Tervala

    2008-01-01

    This study analyses the consequences of productive government spending on the international transmission of fiscal policy. A standard result in the new open economy macroeconomics literature is that a fiscal shock depreciates the exchange rate. I demonstrate that the response of the exchange rate depends on the productivity of government spending. If productivity is sufficiently high, a fiscal shock appreciates the exchange rate. It is also shown that the introduction of productive government...

  4. Considerations for the maximum production rates of triacylglycerol from microalgae

    In recent years, a wide variety of photobioreactors have emerged for producing triacylglycerol (TAG) from microalgae as a feedstock for biodiesel with wildly varying forecasts of TAG and biomass production rates. This research describes the general photobioreactor concept and the dominating factors that determine microalgal production and the maximum attainable production rate of TAG. The information necessary for such an assessment is obtained from published articles and the results are compared to published photobioreactor production rates. Results indicate that at most 9% conversion of available solar energy to TAG is thermodynamically possible, resulting in an annual areal production rate of no more than 23 l m-2 a-1. Given photosynthetic efficiencies and TAG contents of microalgae currently reported, production rates of no more than 15.8 l m-2 a-1 should be anticipated.

  5. The dating of rock surfaces using in situ produced 10Be, 26Al and 36Cl, with examples from Antarctica and the Swiss Alps

    A primary concern today in ice age research is to elucidate the worldwide timing of glacial fluctuations. This information is needed to define the mechanisms by which signals are initiated, and then transferred throughout the various global systems. Because of the importance of integrating the terrestrial records of the former extent of both ice sheets and alpine glaciers, the direct dating of rock surfaces with in situ produced cosmogenic isotopes is an essential tool. These isotopes (e.g. 10Be, 26Al and 36Cl) are produced in the surfaces of rocks due to interactions with cosmic rays. In order to be able to reliably determine exposure ages from rock surfaces with both long and short exposure times, our goal at the onset of this project was to set-up the extraction procedure for Be, Al, Cl from rock samples. 73 separate rock or mineral dissolutions, involving 52 different rock samples, were performed to 1) make sure that meteoric 10Be was being removed, 2) verify the reproducibility of the procedure, and 3) eventually, address several questions on the timing of glacier fluctuations in two specific geographic areas: Antarctica and the Swiss Alps. Exposure dates we have determined from erratic boulders in the Sirius Group sediments at Mount Fleming proved conclusively that this outcrop of the Sirius Group is more than 5.8 million years old. Minimum ages for Sirius Group deposits at Table Mountain and Mount Feather are 2.9 and 2.3 Ma, respectively. Our results have provided support for the idea that the East Antarctic Ice Sheet, a crucial variable in projections of greenhouse scenarios, is a stable feature of Antarctica. We have investigated three key sites in Switzerland related to the timing of glaciations of the Alps. (author) figs., tabs., refs

  6. Reflection of Labour Efficiency (Labour Productivity) within Rates of Return

    CONSTANTIN CĂRUNTU; LOREDANA MIHAELA LĂPĂDUŞI

    2007-01-01

    Within the modern economy, the role of labour acquires primary coordinates, so that the most general and synthetical marker which characterizes the company's efficiency should be measured by labour productivity. The most important role among the multitude of productivity expressions is hold by labour productivity, due to the priority role of labour resource within the range of production factors. The reflection of labour efficiency within rates of return characterizes clearly describes the ex...

  7. ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS

    2007-01-01

    The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point at infinity is absorbing is proved.

  8. Productive Government Spending, Welfare and Exchange Rate Dynamics

    Juha Tervala

    2008-06-01

    Full Text Available This study analyses the consequences of productive government spending on the international transmission of fiscal policy. A standard result in the new open economy macroeconomics literature is that a fiscal shock depreciates the exchange rate. I demonstrate that the response of the exchange rate depends on the productivity of government spending. If productivity is sufficiently high, a fiscal shock appreciates the exchange rate. It is also shown that the introduction of productive government spending increases both domestic and foreign welfare, when compared with the case where government spending is wasted. This is because productive government spending has a positive effect on private consumption in both countries in a two country NOEM model.

  9. Kijkwijzer: The Dutch rating system for audiovisual productions

    Valkenburg, P.M.; Beentjes, J.W.J.; Nikken, P.; Tan, E.S.H.

    2002-01-01

    Kijkwijzer is the name of the new Dutch rating system in use since early 2001 to provide information about the possible harmful effects of movies, home videos and television programs on young people. The rating system is meant to provide audiovisual productions with both age-based and content-based

  10. Norwegian resource policy: The production rate for Norwegian petroleum resources

    Petroleum activities have become a large industry in Norway. This has led to extensive changes in Norwegian economy and society. In the public debate on this activity there has been little discussion of what would be the most profitable production rate. However, it is generally agreed that the great wealth implied by the petroleum resources must be managed in ways suitable to both present and coming generations. This report discusses the production rate based on the following questions: (1) How high can the production rate be before the petroleum activities and the expenditure of the income from them influence the remaining Norwegian economy too strongly? (2) How much of this wealth should reasonably be used by present generations and how much should be left for future generations? There is much to gain from a high tempo and from relocating some of the petroleum wealth. The possibilities of influencing the production rate are mainly connected with the allotments of production licences. The consequences of uncertainties in the petroleum activities for the choice of exploitation tempo are unclear. The environment is not much affected by the production rate. The contractor activity has become Norway's largest industry. 42 refs., 14 figs., 2 tabs

  11. Mapping 15O Production Rate for Proton Therapy Verification

    Purpose: This work was a proof-of-principle study for the evaluation of oxygen-15 (15O) production as an imaging target through the use of positron emission tomography (PET), to improve verification of proton treatment plans and to study the effects of perfusion. Methods and Materials: Dynamic PET measurements of irradiation-produced isotopes were made for a phantom and rabbit thigh muscles. The rabbit muscle was irradiated and imaged under both live and dead conditions. A differential equation was fitted to phantom and in vivo data, yielding estimates of 15O production and clearance rates, which were compared to live versus dead rates for the rabbit and to Monte Carlo predictions. Results: PET clearance rates agreed with decay constants of the dominant radionuclide species in 3 different phantom materials. In 2 oxygen-rich materials, the ratio of 15O production rates agreed with the expected ratio. In the dead rabbit thighs, the dynamic PET concentration histories were accurately described using 15O decay constant, whereas the live thigh activity decayed faster. Most importantly, the 15O production rates agreed within 2% (P>.5) between conditions. Conclusions: We developed a new method for quantitative measurement of 15O production and clearance rates in the period immediately following proton therapy. Measurements in the phantom and rabbits were well described in terms of 15O production and clearance rates, plus a correction for other isotopes. These proof-of-principle results support the feasibility of detailed verification of proton therapy treatment delivery. In addition, 15O clearance rates may be useful in monitoring permeability changes due to therapy

  12. Mapping {sup 15}O Production Rate for Proton Therapy Verification

    Grogg, Kira; Alpert, Nathaniel M.; Zhu, Xuping [Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts (United States); Min, Chul Hee [Department of Radiological Science, College of Health Science, Yonsei University, Wonju, Kangwon (Korea, Republic of); Testa, Mauro; Winey, Brian [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); Normandin, Marc D. [Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts (United States); Shih, Helen A.; Paganetti, Harald; Bortfeld, Thomas [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); El Fakhri, Georges, E-mail: elfakhri@pet.mgh.harvard.edu [Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2015-06-01

    Purpose: This work was a proof-of-principle study for the evaluation of oxygen-15 ({sup 15}O) production as an imaging target through the use of positron emission tomography (PET), to improve verification of proton treatment plans and to study the effects of perfusion. Methods and Materials: Dynamic PET measurements of irradiation-produced isotopes were made for a phantom and rabbit thigh muscles. The rabbit muscle was irradiated and imaged under both live and dead conditions. A differential equation was fitted to phantom and in vivo data, yielding estimates of {sup 15}O production and clearance rates, which were compared to live versus dead rates for the rabbit and to Monte Carlo predictions. Results: PET clearance rates agreed with decay constants of the dominant radionuclide species in 3 different phantom materials. In 2 oxygen-rich materials, the ratio of {sup 15}O production rates agreed with the expected ratio. In the dead rabbit thighs, the dynamic PET concentration histories were accurately described using {sup 15}O decay constant, whereas the live thigh activity decayed faster. Most importantly, the {sup 15}O production rates agreed within 2% (P>.5) between conditions. Conclusions: We developed a new method for quantitative measurement of {sup 15}O production and clearance rates in the period immediately following proton therapy. Measurements in the phantom and rabbits were well described in terms of {sup 15}O production and clearance rates, plus a correction for other isotopes. These proof-of-principle results support the feasibility of detailed verification of proton therapy treatment delivery. In addition, {sup 15}O clearance rates may be useful in monitoring permeability changes due to therapy.

  13. Predicting the production rates of cosmogenic nuclides in extraterrestrial matter

    The production rates of nuclides made by the galactic and solar cosmic rays are important in the interpretations of measurements made with lunar samples, meteorites, and cosmic spherules. Production rates of cosmogenic nuclides have been predicted by a variety of methods that are reviewed in this paper, ranging from systematic studies of one or a group of meteorites to purely theoretical calculations. Production rates can vary with the chemical composition and the preatmospheric depth of the sample and with the size and shape of the object. While the production systematics for cosmogenic nuclides are fairly well known, our ability to predict their production rates can be improved, with a corresponding increase in the scientific return. Additional detailed studies of cosmogenic nuclides in extraterrestrial objects are needed, especially for fairly small and very large objects. Nuclides made in simulation experiments and cross sections for many major nuclear reactions should be measured. Such studies are especially needed for the long-lived radionuclides that have only recently become readily measurable by accelerator mass spectrometry. 34 refs., 5 figs

  14. RADIOLYTIC GAS PRODUCTION RATES OF POLYMERS EXPOSED TO TRITIUM GAS

    Clark, E.

    2013-08-31

    Data from previous reports on studies of polymers exposed to tritium gas is further analyzed to estimate rates of radiolytic gas production. Also, graphs of gas release during tritium exposure from ultrahigh molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, a trade name is Teflon®), and Vespel® polyimide are re-plotted as moles of gas as a function of time, which is consistent with a later study of tritium effects on various formulations of the elastomer ethylene-propylene-diene monomer (EPDM). These gas production rate estimates may be useful while considering using these polymers in tritium processing systems. These rates are valid at least for the longest exposure times for each material, two years for UHMW-PE, PTFE, and Vespel®, and fourteen months for filled and unfilled EPDM. Note that the production “rate” for Vespel® is a quantity of H{sub 2} produced during a single exposure to tritium, independent of length of time. The larger production rate per unit mass for unfilled EPDM results from the lack of filler- the carbon black in filled EPDM does not produce H{sub 2} or HT. This is one aspect of how inert fillers reduce the effects of ionizing radiation on polymers.

  15. Planning Horizon for Production Inventory Models with Production Rate Dependent on Demand and Inventory Level

    Jennifer Lin; Chao, Henry C. J.; Peterson Julian

    2013-01-01

    This paper discusses why the selection of a finite planning horizon is preferable to an infinite one for a replenishment policy of production inventory models. In a production inventory model, the production rate is dependent on both the demand rate and the inventory level. When there is an exponentially decreasing demand, the application of an infinite planning horizon model is not suitable. The emphasis of this paper is threefold. First, while pointing out questionable results from a previo...

  16. Reaction rate and energy-loss rate for photopair production by relativistic nuclei

    Chodorowski, Michal J.; Zdziarski, Andrzej A.; Sikora, Marek

    1992-01-01

    The process of e(+/-) pair production by relativistic nuclei on ambient photons is considered. The process is important for cosmic-ray nuclei in interstellar and intergalactic space as well as in galactic and extragalactic compact objects. The rate of this process is given by an integral of the cross section over the photon angular and energy distribution. In the case of isotropic photons, the angular integration is performed to provide an expression for the rate at given photon energy in the nucleus rest frame. The total rate then becomes a single integral of that rate over the photon energy distribution. Formulas are also given for the fractional energy loss of a relativistic nucleus colliding with a photon of a given energy in the rest frame. The nucleus energy-loss rate is integrated over the photon angular distribution in the case of isotropic photons, and simple fits are provided.

  17. 5 CFR 532.253 - Special rates or rate ranges for leader, supervisory, and production facilitating positions.

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Special rates or rate ranges for leader....253 Special rates or rate ranges for leader, supervisory, and production facilitating positions. (a... shall establish special rates for leader, supervisory, and production facilitating positions,...

  18. Modeling Electric Discharges with Entropy Production Rate Principles

    Thomas Christen

    2009-12-01

    Full Text Available Under which circumstances are variational principles based on entropy production rate useful tools for modeling steady states of electric (gas discharge systems far from equilibrium? It is first shown how various different approaches, as Steenbeck’s minimum voltage and Prigogine’s minimum entropy production rate principles are related to the maximum entropy production rate principle (MEPP. Secondly, three typical examples are discussed, which provide a certain insight in the structure of the models that are candidates for MEPP application. It is then thirdly argued that MEPP, although not being an exact physical law, may provide reasonable model parameter estimates, provided the constraints contain the relevant (nonlinear physical effects and the parameters to be determined are related to disregarded weak constraints that affect mainly global entropy production. Finally, it is additionally conjectured that a further reason for the success of MEPP in certain far from equilibrium systems might be based on a hidden linearity of the underlying kinetic equation(s.

  19. Factors affecting production rates of cosmogenic nuclides in extraterrestrial matter

    Reedy, R. C.

    2015-10-01

    Good production rates are needed for cosmic-ray-produced nuclides to interpret their measurements. Rates depend on many factors, especially the pre-atmospheric object's size, the location of the sample in that object (such as near surface or deep inside), and the object's bulk composition. The bulk composition affects rates, especially in objects with very low and very high iron contents. Extraterrestrial materials with high iron contents usually have higher rates for making nuclides made by reactions with energetic particles and lower rates for the capture of thermal neutrons. In small objects and near the surface of objects, the cascade of secondary neutrons is being developed as primary particles are being removed. Deep in large objects, that secondary cascade is fully developed and the fluxes of primary particles are low. Recent work shows that even the shape of an object in space has a small but measureable effect. Work has been done and continues to be done on better understanding those and other factors. More good sets of measurements in meteorites with known exposure geometries in space are needed. With the use of modern Monte Carlo codes for the production and transport of particles, the nature of these effects have been and is being studied. Work needs to be done to improve the results of these calculations, especially the cross sections for making spallogenic nuclides.

  20. Diffusion of HTO, {sup 36}Cl{sup -}, {sup 125}I{sup -} and {sup 22}Na{sup +} in Opalinus Clay: Effect of Confining Pressure, Sample Orientation, Sample Depth and Temperature

    Van Loon, L.R.; Soler, J.M

    2004-02-01

    Effective diffusion coefficients (D{sub e}), rock capacity factors ({alpha}) and diffusion-accessible porosities ({epsilon}) were measured using the through-diffusion technique. Transport (diffusion) was measured both perpendicular and parallel to the bedding. Special cells that allowed the application of an axial confining pressure were designed. The pressures applied ranged from 1 to 5 MPa for Mont Terri samples and between 4 and 15 MPa for Benken samples, the upper values representing the in-situ confining pressure at both locations. The test solutions used in the experiments were synthetic Opalinus Clay pore water, which has Na and Cl as main components (Mont Terri: I = 0.39 M; Benken: I = 0.20 M). Pressure only had a small effect on the value of the effective diffusion coefficients. In the case of Mont Terri samples, increasing the pressure from 1 to 5 MPa resulted in a decrease of the effective diffusion coefficient of 20% for HTO, 27% for {sup 36}Cl{sup -}, 29% for {sup 125}I{sup -} and 17 % for {sup 22}Na{sup +}. In the case of Benken samples, increasing the pressure from 4 to 15 MPa resulted in a decrease of D{sub e} of 17% for HTO, 22% for {sup 36}Cl{sup -}, 32% for {sup 125}I{sup -} and 17 % for {sup 22}Na{sup +}. Moreover, the effective diffusion coefficients for for {sup 36}Cl{sup -}are smaller than for HTO, which is consistent with an effect arising from anion exclusion. This ion exclusion effect is smaller in samples from Mont Terri than in samples from Benken, which can be explained by the higher ionic strength of the Mont Terri water used in the experiments. The diffusion of {sup 22}Na{sup +} is similar to that of HTO in the case of Mont Terri OPA. For Benken OPA, the D{sub e} value of {sup 22}Na{sup +} is a factor of 2 higher than that of HTO. This last observation cannot be explained so far but is comparable to experimental data from ANDRA (1999) on Callovo-Oxfordian claystones from the Meuse/Haute Same site. {sup 125}I{sup -} is retarded with

  1. Production rate calculations for a secondary beam facility

    Jiang, C.L.; Back, B.B.; Rehm, K.E.

    1995-08-01

    In order to select the most cost-effective method for the production of secondary ion beams, yield calculations for a variety of primary beams were performed ranging in mass from protons to {sup 18}O with energies of 100-200 MeV/u. For comparison, production yields for 600-1000 MeV protons were also calculated. For light ion-(A < {sup 4}He) induced reactions at energies above 50 MeV/u the LAHET code was used while the low energy calculations were performed with LPACE. Heavy-ion-induced production rates were calculated with the ISAPACE program. The results of these codes were checked against each other and wherever possible a comparison with experimental data was performed. These comparisons extended to very exotic reaction channels, such as the production of {sup 100}Sn from {sup 112}Sn and {sup 124}Xe induced fragmentation reactions. These comparisons indicate that the codes are able to predict production rates to within one order of magnitude.

  2. The Production Rate and Employment of Ph.D. Astronomers

    Metcalfe, Travis S.

    2007-01-01

    In an effort to encourage self-regulation of the astronomy job market, I examine the supply of, and demand for, astronomers over time. On the supply side, I document the production rate of Ph.D. astronomers from 1970 to 2006 using the UMI Dissertation Abstracts database, along with data from other independent sources. I compare the long-term trends in Ph.D. production with federal astronomy research funding over the same time period, and I demonstrate that additional funding is correlated wit...

  3. Minimizing Entropy Production Rate in Binary Tray Distillation

    Signe Kjelstrup

    2000-09-01

    Full Text Available

    In this work we increase the second law efficiency in an ideal binary tray distillation column by allowing heat exchangers on all trays. We find by numerical optimization, the duties of the heat exchangers that give the highest second law efficiency of the column. The entropy production rate was reduced by 30-50% compared to adiabatic operation for two different columns. The numerical optimum was in agreement with the result of an Euler-Lagrange minimization in which the total entropy production rate was described by irreversible thermodynamics. The minimum was not characterized by equipartition of forces.

    • This paper was presented at ECOS'00, Enschede, July 5-7, 2000 

  4. Understanding Real Exchange Rate Movements with Trade in Intermediate Products

    Parsley, David; Popper, Helen

    2009-01-01

    We suggest it may be "too easy" to attribute real exchange rate movements to law of one price deviations. We show that it is immaterial whether one uses seemingly traded goods, nontraded goods, or even just a single, unimportant consumer good, say beer. The ease of attributing the variation to any such deviations is explained using a model with intermediate goods trade. In the model, the stage of production determines the traded/nontraded distinction. We find empirical substantiation for the ...

  5. High-rate fermentative hydrogen production from beverage wastewater

    Highlights: • Hybrid immobilized-bacterial cells show stable operation over 175 days. • Low HRT of 1.5 h shows peak hydrogen production rate of 55 L/L-d. • Electricity generation is 9024 kW-d from 55 L/L-d hydrogen using beverage wastewater. • Granular sludge formed only at 2–3 h HRT with presence of Selenomonas sp. - Abstract: Hydrogen production from beverage industry wastewater (20 g/Lhexose equivalent) using an immobilized cell reactor with a continuous mode of operation was studied at various hydraulic retention times (HRT, 8–1.5 h). Maximum hydrogen production rate (HPR) of 55 L/L-d was obtained at HRT 1.5 h (an organic loading of 320 g/L-dhexose equivalent). This HPR value is much higher than those of other industrial wastewaters employed in fermentative hydrogen production. The cell biomass concentration peaked at 3 h HRT with a volatile suspended solids (VSS) concentration of 6.31 g/L (with presence of self-flocculating Selenomonas sp.), but it dropped to 3.54 gVSS/L at 1.5 h HRT. With the shortening of HRT, lactate concentration increased but the concentration of the dominant metabolite butyrate did not vary significantly. The Clostridium species dynamics was not significantly affected, but total microbial community structure changed with respect to HRT variation as evident from PCR–DGGE analyses. Analysis of energy production rate suggests that beverage wastewater is a high energy yielding feedstock, and can replace 24% of electricity consumption in a model beverage industry

  6. Cosmogenic Nuclei Production Rate on the Lunar Surface

    Dong, Tie-Kuang; Ma, Tao; Chang, Jin; Dong, Wu-Dong; Zhang, Xiao-Ping; Li, Guo-Long; Ren, Zhong-Zhou

    2013-01-01

    A physical model of Geant4-based simulation of galactic cosmic ray (GCR) particles interaction with the lunar surface matter has been developed to investigate the production rate of cosmogenic nuclei. In this model the GCRs, mainly very high energy protons and $\\alpha$ particles, bombard the surface of the Moon and produce many secondary particles such as protons and neutrons. The energies of proton and neutron at different depths are recorded and saved into ROOT files, and the analytical expressions for the differential proton and neutron fluxes are obtained through the best-fit procedure under the ROOT software. To test the validity of this model, we calculate the production rates of long-lived nuclei $^{10}$Be and $^{26}$Al in the Apollo 15 long drill core by combining the above differential fluxes and the newly evaluated spallation reaction cross sections. Numerical results show that the theoretical production rates agree quite well with the measured data. It means that this model works well. Therefore, i...

  7. Photochemical free radical production rates in the eastern Caribbean

    Dister, Brian; Zafiriou, Oliver C.

    1993-02-01

    Potential photochemical production rates of total (NO-scavengeable) free radicals were surveyed underway (> 900 points) in the eastern Caribbean and Orinoco delta in spring and fall 1988. These data document seasonal trends and large-scale (˜ 10-1000 km) variability in the pools of sunlight-generated reactive transients, which probably mediate a major portion of marine photoredox transformations. Radical production potential was detectable in all waters and was reasonably quantifiable at rates above 0.25 nmol L-1 min-1 sun-1. Radical production rates varied from ˜ 0.1-0.5 nmol L-1 min-1 of full-sun illumination in "blue water" to > 60 nmol L-1 min-1 in some estuarine waters in the high-flow season. Qualitatively, spatiotemporal potential rate distributions strikingly resembled that of "chlorophyll" (a riverine-influence tracer of uncertain specificity) in 1979-1981 CZCS images of the region [Müller-Karger et al., 1988] at all scales. Basin-scale occurrence of greatly enhanced rates in fall compared to spring is attributed to terrestrial chromophore inputs, primarily from the Orinoco River, any contributions from Amazon water and nutrient-stimulus effects could not be resolved. A major part of the functionally photoreactive colored organic matter (COM) involved in radical formation clearly mixes without massive loss out into high-salinity waters, although humic acids may flocculate in estuaries. A similar conclusion applies over smaller scales for COM as measured optically [Blough et al., this issue]. Furthermore, optical absorption and radical production rates were positively correlated in the estuarine region in fall. These cruises demonstrated that photochemical techniques are now adequate to treat terrestrial photochemical chromophore inputs as an estuarine mixing problem on a large scale, though the ancillary data base does not currently support such an analysis in this region. Eastern Caribbean waters are not markedly more reactive at comparable salinities

  8. Relating Productivity Events to Holocene Bivalve Shell Growth Rates

    Huntley, J. W.; Krause, R. A.; Kowalewski, M.; Romanek, C. S.; Kaufman, D. S.; Simoes, M. G.

    2007-12-01

    The growth rate of a bivalve can be influenced by many environmental factors that can change during the life of the organism. In this contribution we present initial data from a millennium scale chronology to assess the relationship between ontogenetic growth in the bivalve Semele casali and paleoenvironmental conditions preserved in the shell using growth increment analysis, radiocarbon-calibrated amino acid racemization dating techniques, stable isotopes (C and O) and high spatial resolution (125-150 samples per cm of shell profile) trace element (Ba, Mn) analysis (LA-ICPMS). Time-averaged specimens of S. casali were dredged from two sites at 10 meters and 30 meters depth along the inner continental shelf at Ubatuba Bay in the Southeast Brazilian Bight, an area influenced by productivity pulses triggered by coastal runoff events and coastal upwelling. Seventy-five individual valves were dated using amino acid racemization (aspartic acid). Dates were calculated using an expanded version of a previously published relationship (Barbour Wood et al., 2006 Quaternary Research 323- 331) between aspartic acid ratios and AMS radiocarbon dates of twelve S. casali individuals from the same sampling locations. The resulting time series has complete coverage for the past three thousand years at centennial resolution. From this time series, a sub-sample of dated valves was selected for more detailed growth increment, stable isotope and high-resolution trace element (Ba/Ca and Mn/Ca) analyses. Oceanic productivity is expressed differentially in the trace element profiles of S. casali with elevated Ba/Ca and Mn/Ca ratios capturing nutrient input through coastal runoff events while elevated Ba/Ca and depressed Mn/Ca ratios represent input through coastal upwelling. Fluctuations in Ba/Ca and Mn/Ca are not correlated to fluctuations in relative growth throughout the ontogeny of an individual bivalve, nor are they expected to be as periods of increased productivity are transient

  9. Semiclassical pair production rate for rotating electric fields

    Strobel, Eckhard

    2014-01-01

    We semiclassically investigate Schwinger pair production for pulsed rotating electric fields depending on time. To do so we solve the Dirac equation for two-component fields in a WKB-like approximation. The result shows that for two-component fields the spin distribution of produced pairs is generally not $1:1$. As a result the pair creation rates of spinor and scalar quantum electro dynamics (QED) are different even for one pair of turning points. For rotating electric fields the pair creation rate is dominated by particles with a specific spin depending on the sense of rotation. We present an analytical solution for the momentum spectrum of the constant rotating field. We find interference effects not only in the momentum spectrum but also in the total particle number of rotating electric fields.

  10. Lifetime and production rate of beauty baryons from Z decays

    Abreu, P; Adye, T; Agasi, E; Ajinenko, I; Aleksan, Roy; Alekseev, G D; Allport, P P; Almehed, S; Alvsvaag, S J; Amaldi, Ugo; Amato, S; Andreazza, A; Andrieux, M L; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barate, R; Barbiellini, Guido; Bardin, Dimitri Yuri; Barker, G J; Baroncelli, A; Bärring, O; Barrio, J A; Bartl, Walter; Bates, M J; Battaglia, Marco; Baubillier, M; Baudot, J; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Benvenuti, Alberto C; Berggren, M; Bertrand, D; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bloch, D; Blume, M; Blyth, S; Bocci, V; Bolognese, T; Bonesini, M; Bonivento, W; Booth, P S L; Borisov, G; Bosio, C; Bosworth, S; Botner, O; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozzo, M; Branchini, P; Brand, K D; Brenner, R A; Bricman, C; Brillault, L; Brown, R C A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Buys, A; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Cankocak, K; Cao, F; Carena, F; Carrilho, P; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Cerrito, L; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Chauveau, J; Checchia, P; Chelkov, G A; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Cindro, V; Collins, P; Contreras, J L; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Dahl-Jensen, Erik; Dahm, J; D'Almagne, B; Dam, M; Damgaard, G; Daum, A; Dauncey, P D; Davenport, Martyn; Da Silva, W; Defoix, C; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; De Boeck, H; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; De Saint-Jean, C; Dijkstra, H; Di Ciaccio, Lucia; Djama, F; Dolbeau, J; Dönszelmann, M; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Dufour, Y; Dupont, F; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Elsing, M; Engel, J P; Ershaidat, N; Erzen, B; Espirito-Santo, M C; Falk, E; Fassouliotis, D; Feindt, Michael; Fenyuk, A; Ferrer, A; Filippas-Tassos, A; Firestone, A; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frenkiel, P; Fries, D E C; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fürstenau, H; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gibbs, M; Gillespie, D; Gokieli, R; Golob, B; Gopal, Gian P; Gorn, L; Górski, M; Gracco, Valerio; Graziani, E; Grosdidier, G; Gunnarsson, P; Günther, M; Guy, J; Haedinger, U; Hahn, F; Hahn, M; Hahn, S; Hajduk, Z; Hallgren, A; Hamacher, K; Hao, W; Harris, F J; Hedberg, V; Henriques, R P; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Higón, E; Hilke, Hans Jürgen; Hill, T S; Holmgren, S O; Holt, P J; Holthuizen, D J; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Ioannou, P; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, Christian; Juillot, P; Kaiser, M; Kalmus, George Ernest; Kapusta, F; Karlsson, M; Karvelas, E; Katsanevas, S; Katsoufis, E C; Keränen, R; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klein, H; Klovning, A; Kluit, P M; Köhne, J H; Köne, B; Kokkinias, P; Koratzinos, M; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Kramer, P H; Krammer, Manfred; Kreuter, C; Królikowski, J; Kronkvist, I J; Krumshtein, Z; Krupinski, W; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Laktineh, I; Lamblot, S; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Lapin, V; Last, I; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leitner, R; Lemoigne, Y; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Liko, D; Lindner, R; Lipniacka, A; Lippi, I; Lörstad, B; Lokajícek, M; Loken, J G; López, J M; López-Fernandez, A; López-Aguera, M A; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Maehlum, G; Maio, A; Malychev, V; Mandl, F; Marco, J; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Maron, T; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, M; McCubbin, M L; McKay, M; McNulty, M; Medbo, J; Meroni, C; Meyer, W T; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Morettini, P; Müller, H; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Negri, P; Némécek, S; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Niss, P; Nomerotski, A; Normand, Ainsley; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Ostankov, A P; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Pagès, P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Piana, G; Pierre, F; Plaszczynski, S; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Prest, M; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Rames, J; Ratoff, P N; Read, A L; Reale, M; Rebecchi, P; Redaelli, N G; Reid, D; Renton, P B; Resvanis, L K; Richard, F; Richardson, J; Rídky, J; Rinaudo, G; Ripp, I; Romero, A; Roncagliolo, I; Ronchese, P; Roos, L; Rosenberg, E I; Rosso, E; Roudeau, Patrick; Rovelli, T; Rückstuhl, W; Ruhlmann-Kleider, V; Ruiz, A; Rybicki, K; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sánchez, J; Sannino, M; Schneider, H; Schyns, M A E; Sciolla, G; Scuri, F; Sedykh, Yu; Segar, A M; Seitz, A; Sekulin, R L; Shellard, R C; Siccama, I; Siegrist, P; Simonetti, S; Simonetto, F; Sissakian, A N; Sitár, B; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Squarcia, S; Stäck, H; Stanescu, C; Stapnes, Steinar; Stavitski, I; Stepaniak, K; Stichelbaut, F; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tavernet, J P; Chikilev, O G; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Toet, D Z; Tomaradze, A G; Tomé, B; Torassa, E; Tortora, L; Tranströmer, G; Treille, D; Trischuk, W; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Überschär, S; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Doninck, W K; Van Eldik, J; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Wehr, A; Weierstall, M; Weilhammer, Peter; Wetherell, Alan M; Wicke, D; Wickens, J H; Wielers, M; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Wormser, G; Woschnagg, K; Yip, K; Zach, F; Zacharatou-Jarlskog, C; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zito, M; Zontar, D; Zuberi, R; Zucchelli, G C; Zumerle, G

    1995-01-01

    The production and decay of beauty baryons (b-baryons) have been studied using 1.7 \\times 10^6 Z hadronic decays collected by the DELPHI detector at LEP. Three different techniques were used to identify the b-baryons. The first method used pairs of a \\Lambda and a lepton to tag the b-baryon decay. The second method associated fully reconstructed \\Lambda_c baryons with leptons. The third analysis reconstructed the b-baryon decay points by forming secondary vertices from identified protons and muons of opposite sign. Using these methods the following production rates were measured: \\begin{eqnarray*} f(\\qb \\ra \\Bb) \\times \\BR(\\Bb \\ra \\mLs \\ell\\bar{\

  11. The Production Rate and Employment of Ph.D. Astronomers

    Metcalfe, Travis S.

    2008-02-01

    In an effort to encourage self-regulation of the astronomy job market, I examine the supply of, and demand for, astronomers over time. On the supply side, I document the production rate of Ph.D. astronomers from 1970 to 2006 using the UMI Dissertation Abstracts database, along with data from other independent sources. I compare the long-term trends in Ph.D. production with federal astronomy research funding over the same time period, and I demonstrate that additional funding is correlated with higher subsequent Ph.D. production. On the demand side, I monitor the changing patterns of employment using statistics about the number and types of jobs advertised in the AAS Job Register from 1984 to 2006. Finally, I assess the sustainability of the job market by normalizing this demand by the annual Ph.D. production. The most recent data suggest that there are now annual advertisements for about one postdoctoral job, half a faculty job, and half a research/support position for every new domestic Ph.D. recipient in astronomy and astrophysics. The average new astronomer might expect to hold up to 3 jobs before finding a steady position.

  12. The Production Rate and Employment of Ph.D. Astronomers

    Metcalfe, Travis S

    2007-01-01

    In an effort to promote self-regulation of the astronomy job market, I examine the supply of, and demand for, astronomers over time. On the supply side, I document the production rate of Ph.D. astronomers from 1970 to 2006 using the UMI Dissertation Abstracts database, along with data from other independent sources. I compare the long-term trends in Ph.D. production with federal astronomy research funding over the same time period, and I demonstrate that additional funding is correlated with higher subsequent Ph.D. production. On the demand side, I monitor the changing patterns of employment using statistics about the number and types of jobs advertised in the AAS Job Register from 1984 to 2006. Finally, I assess the sustainability of the job market by normalizing this demand by the annual Ph.D. production. The most recent data suggest that there are now annual advertisements for about one postdoctoral job, half a faculty job, and half a research/support position for every new domestic Ph.D. recipient in astr...

  13. The Production Rate and Employment of Ph.D. Astronomers

    Metcalfe, Travis S.

    2007-05-01

    As in many sciences, the production rate of new Ph.D. astronomers is decoupled from the global demand for trained scientists. As noted by Thronson (1991, PASP, 103, 90), overproduction appears to be built into the system, making the mathematical formulation of surplus astronomer production similar to that for industrial pollution models -- an unintended side effect of the process. Following Harris (1994, ASP Conf., 57, 12), I document the production of Ph.D. astronomers from 1990 to 2005 using the online Dissertation Abstracts database. To monitor the changing patterns of employment, I examine the number of postdoctoral, tenure-track, and other jobs advertised in the AAS Job Register during this same period. Although the current situation is clearly unsustainable, it was much worse a decade ago with nearly 7 new Ph.D. astronomers in 1995 for every new tenure-track job. While the number of new permanent positions steadily increased throughout the late 1990's, the number of new Ph.D. recipients gradually declined. After the turn of the century, the production of new astronomers leveled off, but new postdoctoral positions grew dramatically. There has also been recent growth in the number of non-tenure-track lecturer, research, and support positions. This is just one example of a larger cultural shift to temporary employment that is happening throughout society -- it is not unique to astronomy.

  14. Buyer-vendor coordination for fixed lifetime product with quantity discount under finite production rate

    Zhang, Qinghong; Luo, Jianwen; Duan, Yongrui

    2016-03-01

    Buyer-vendor coordination has been widely addressed; however, the fixed lifetime of the product is seldom considered. In this paper, we study the coordination of an integrated production-inventory system with quantity discount for a fixed lifetime product under finite production rate and deterministic demand. We first derive the buyer's ordering policy and the vendor's production batch size in decentralised and centralised systems. We then compare the two systems and show the non-coordination of the ordering policies and the production batch sizes. To improve the supply chain efficiency, we propose quantity discount contract and prove that the contract can coordinate the buyer-vendor supply chain. Finally, we present analytically tractable solutions and give a numerical example to illustrate the benefits of the proposed quantity discount strategy.

  15. Hydrogen production rate from comet Austin 1982g

    Shih, P.; Scherb, F.; Roesler, F. L.

    1984-01-01

    Meaningful measurements with respect to the cometary Balmer-alpha (H-alpha) emission are difficult and require the use of special equipment. The first ground-based observations of H-alpha emission from a cometary hydrogen corona were conducted on comet Kohoutek 1973 XII with a large-aperture Fabry-Perot spectrometer installed at the McMath solar telescope at Kitt Peak National Observatory. The present investigation is concerned with the second ground-based observations of cometary H-alpha emission carried out during the apparition of comet Austin 1982g. A 150 mm dual-etalon Fabry-Perot spectrometer was employed in the experiment. Use was made of an observatory which is designed for the high spectral resolution study of faint extended sources such as interstellar and geocoronal emission lines. The investigation demonstrates that hydrogen production rates from comets as faint as about 7th magnitude can be routinely measured from the ground at minimal cost.

  16. Recent developments in cosmogenic nuclide production rate scaling

    Lifton, N. A.

    2013-12-01

    A new cosmogenic nuclide production rate scaling model based on analytical fits to Monte Carlo simulations of atmospheric cosmic ray flux spectra (both of which agree well with measured spectra) enables identification and quantification of the biases in previously published models (Lifton, N., Sato, T., Dunai, T., in review, Earth and Planet. Sci. Lett.). Scaling predictions derived from the new model (termed LSD) suggest two potential sources of bias in the previous models: different energy responses of the secondary neutron detectors used in developing the models, and different geomagnetic parameterizations. In addition, the particle flux spectra generated by the LSD model allow one to generate nuclide-specific scaling factors that reflect the influences of the flux energy distribution and the relevant excitation functions (probability of nuclide production in a given nuclear reaction as a function of energy). Resulting scaling factors indicate 3He shows the strongest positive deviation from the flux-based scaling, while 14C exhibits a negative deviation. These results are consistent with previous studies showing an increasing 3He/10Be ratio with altitude in the Himalayas, but with a much lower magnitude for the effect. Furthermore, the new model provides a flexible framework for exploring the implications of future advances in model inputs. For example, the effects of recently updated paleomagnetic models (e.g. Korte et al., 2011, Earth and Planet Sci. Lett. 312, 497-505) on scaling predictions will also be presented.

  17. A Deterministic Inventory/Production Model with General Inventory Cost Rate Function and Concave Production Costs

    S.I. Birbil (Ilker); J.B.G. Frenk (Hans); Z.P. Bayindir (Pelin)

    2004-01-01

    textabstractWe present a thorough analysis of the economic order quantity model with shortages under a general inventory cost rate function and concave production costs. By using some standard results from convex analysis, we show that the model exhibits a composite concave-convex structure. Consequ

  18. Modeling gallic acid production rate by empirical and statistical analysis

    Bratati Kar

    2000-01-01

    Full Text Available For predicting the rate of enzymatic reaction empirical correlation based on the experimental results obtained under various operating conditions have been developed. Models represent both the activation as well as deactivation conditions of enzymatic hydrolysis and the results have been analyzed by analysis of variance (ANOVA. The tannase activity was found maximum at incubation time 5 min, reaction temperature 40ºC, pH 4.0, initial enzyme concentration 0.12 v/v, initial substrate concentration 0.42 mg/ml, ionic strength 0.2 M and under these optimal conditions, the maximum rate of gallic acid production was 33.49 mumoles/ml/min.Para predizer a taxa das reações enzimaticas uma correlação empírica baseada nos resultados experimentais foi desenvolvida. Os modelos representam a ativação e a desativativação da hydrolise enzimatica. Os resultados foram avaliados pela análise de variança (ANOVA. A atividade máxima da tannase foi obtida após 5 minutos de incubação, temperatura 40ºC, pH 4,0, concentração inicial da enzima de 0,12 v/v, concentração inicial do substrato 0,42 mg/ml, força iônica 0,2 M. Sob essas condições a taxa máxima de produção ácido galico foi de 33,49 µmoles/ml/min.

  19. Cosmogenic 36Cl exposure ages reveal a 9.3 ka BP glacier advance and the Late Weichselian-Early Holocene glacial history of the Drangajökull region, northwest Iceland

    Brynjólfsson, Skafti; Schomacker, Anders; Ingólfsson, Ólafur; Keiding, Jakob K.

    2015-10-01

    We present twenty-four new cosmogenic isotope (36Cl) surface exposure ages from erratic boulders, moraine boulders and glacially eroded bedrock that constrain the late Weichselian to Holocene glacial history of the Drangajökull region, northwest Iceland. The results suggest a topographically controlled ice sheet over the Vestfirðir (Westfjords) peninsula during the last glaciation. Cold based non-erosive sectors of the ice sheet covered most of the mountains while fjords and valleys were occupied with erosive, warm-based ice. Old36Cl exposure ages from highlands and mountain plateaux (L8; 76.5 ka and H1; 41.6 ka) in combination with younger erratic boulders (L7; 26.2 and K1-K4; 15.0-13.8 ka) superimposed on such surfaces suggest the presence of non-erosive ice over uplands and plateaux in the Vestfirðir peninsula during the last glaciation. Glacially scoured terrain and erratic boulders yielding younger exposure ages (L1-L6; 11.3-9.1 ka and R1, R6-R7; 10.6-9.4 ka) in the lowland areas indicate that the valleys and fjords of the Vestfirðir peninsula were occupied by warm-based, dynamic ice during the last glaciation. The deglaciation of mountain Leirufjall by 26.2 ka BP suggests that ice thinning and deglaciation of some mountains and plateaux preceded any significant lateral retreat of the ice sheet. Subsequently this initial ice thinning was followed by break-up of the shelf based ice sheet off Vestfirðir about 15 ka BP. Hence, the new exposure ages suggest a stepwise asynchronous deglaciation on land, following the shelf break-up with some valleys and most of the highlands, ice free by 14-15 ka BP. The outermost moraine at the mouth of Leirufjörður is dated to 9.3 ka BP, and we suggest the moraine to be formed by a glacier re-advance in response to a cooler climate forced by the reduced Atlantic Meridional Overturning Circulation at around 9.3 ka BP. A system of moraines proximal to the 9.3 ka moraine in Leirufjörður as well as a 9.4 ka deglaciation age

  20. The Rate-of-Return Regulated Firm: Cost and Production Duality

    Rolf Fare; James Logan

    1983-01-01

    A duality between cost and production is established for a firm subject to rate-of-return regulation. To this end, a rate-of-return regulated production function is defined and shown to exist. It is then shown how information regarding the unregulated technology can be obtained from the rate-of-return regulated cost function. With knowledge of the rate-of-return constraint, the rate-of-return regulated production function can be reconstructed.

  1. Determination of optimal lot size and production rate for multi-production channels with limited capacity

    Huang, Yeu-Shiang; Wang, Ruei-Pei; Ho, Jyh-Wen

    2015-07-01

    Due to the constantly changing business environment, producers often have to deal with customers by adopting different procurement policies. That is, manufacturers confront not only predictable and regular orders, but also unpredictable and irregular orders. In this study, from the perspective of upstream manufacturers, both regular and irregular orders are considered in coping with the situation in which an uncertain demand is faced by the manufacturer, and a capacity confirming mechanism is used to examine such demand. If the demand is less than or equal to the capacity of the ordinary production channel, the general supply channel is utilised to fully account for the manufacturing process, but if the demand is greater than the capacity of the ordinary production channel, the contingency production channel would be activated along with the ordinary channel to satisfy the upcoming high demand. Besides, the reproductive property of the probability distribution is employed to represent the order quantity of the two types of demand. Accordingly, the optimal production rates and lot sizes for both channels are derived to provide managers with insights for further production planning.

  2. Improved estimates of environmental copper release rates from antifouling products.

    Finnie, Alistair A

    2006-01-01

    The US Navy Dome method for measuring copper release rates from antifouling paint in-service on ships' hulls can be considered to be the most reliable indicator of environmental release rates. In this paper, the relationship between the apparent copper release rate and the environmental release rate is established for a number of antifouling coating types using data from a variety of available laboratory, field and calculation methods. Apart from a modified Dome method using panels, all laboratory, field and calculation methods significantly overestimate the environmental release rate of copper from antifouling coatings. The difference is greatest for self-polishing copolymer antifoulings (SPCs) and smallest for certain erodible/ablative antifoulings, where the ASTM/ISO standard and the CEPE calculation method are seen to typically overestimate environmental release rates by factors of about 10 and 4, respectively. Where ASTM/ISO or CEPE copper release rate data are used for environmental risk assessment or regulatory purposes, it is proposed that the release rate values should be divided by a correction factor to enable more reliable generic environmental risk assessments to be made. Using a conservative approach based on a realistic worst case and accounting for experimental uncertainty in the data that are currently available, proposed default correction factors for use with all paint types are 5.4 for the ASTM/ISO method and 2.9 for the CEPE calculation method. Further work is required to expand this data-set and refine the correction factors through correlation of laboratory measured and calculated copper release rates with the direct in situ environmental release rate for different antifouling paints under a range of environmental conditions. PMID:17110352

  3. Enhance Production Rate of Braiding Machine Using Speed Reduction Technique

    Manoj A. Kumbhalkar; Sachin V. Mate; Sushama Dhote; Mudra Gondane

    2013-01-01

    Textile designing is a technical process which includes different methods for production of textile, surface design and structural design of a textile. Braid is the textile product having various types like round and flat braid made by using textile threads or wires which are alternatively interwoven in braiding machine. A small scale industry in Nagpur produces each type of cotton braids using 16 spindle braiding machines on the single line shaft acquired power from 0.50 HP motor runs at 144...

  4. Interwell Connectivity and Diagnosis Using Correlation of Production and Injection Rate Data in Hydrocarbon Production

    Jerry L. Jensen; Larry W. Lake; Ali Al-Yousef; Dan Weber; Ximing Liang; T.F. Edgar; Nazli Demiroren; Danial Kaviani

    2007-03-31

    This report details progress and results on inferring interwell communication from well rate fluctuations. Starting with the procedure of Albertoni and Lake (2003) as a foundation, the goal of the project was to develop further procedures to infer reservoir properties through weights derived from correlations between injection and production rates. A modified method, described in Yousef and others (2006a,b), and herein referred to as the 'capacitance model', is the primary product of this research project. The capacitance model (CM) produces two quantities, {lambda} and {tau}, for each injector-producer well pair. For the CM, we have focused on the following items: (1) Methods to estimate {lambda} and {tau} from simulated and field well rates. The original method uses both non-linear and linear regression and lacks the ability to include constraints on {lambda} and {tau}. The revised method uses only non-linear regression, permitting constraints to be included as well as accelerating the solution so that problems with large numbers of wells are more tractable. (2) Approaches to integrate {lambda} and {tau} to improve connectivity evaluations. Interpretations have been developed using Lorenz-style and log-log plots to assess heterogeneity. Testing shows the interpretations can identify whether interwell connectivity is controlled by flow through fractures, high-permeability layers, or due to partial completion of wells. Applications to the South Wasson and North Buck Draw Fields show promising results. (3) Optimization of waterflood injection rates using the CM and a power law relationship for watercut to maximize economic return. Tests using simulated data and a range of oil prices show the approach is working. (4) Investigation of methods to increase the robustness of {lambda} and {tau} estimates. Human interventions, such as workovers, also cause rate fluctuations and can be misinterpreted by the model if bottom hole pressure data are not available. A

  5. High biomass sorghum production across tillage systems and nitrogen rates

    Bioenergy production has traditionally focused on perennial crops; however, these crops require an establishment period before they can be utilized. High biomass sorghum (Sorghum bicolor L. Moench) grown as an annual crop can be used during this establishment period, but typical yields and nutrient...

  6. Modeling gallic acid production rate by empirical and statistical analysis

    Kar Bratati; Banerjee Rintu; Bhattacharyya Bimal Chandra

    2000-01-01

    For predicting the rate of enzymatic reaction empirical correlation based on the experimental results obtained under various operating conditions have been developed. Models represent both the activation as well as deactivation conditions of enzymatic hydrolysis and the results have been analyzed by analysis of variance (ANOVA). The tannase activity was found maximum at incubation time 5 min, reaction temperature 40ºC, pH 4.0, initial enzyme concentration 0.12 v/v, initial substrate concentra...

  7. r-Process Lanthanide Production and Heating Rates in Kilonovae

    Lippuner, Jonas

    2015-01-01

    r-Process nucleosynthesis in material ejected during neutron star mergers may lead to radioactively powered transients called kilonovae. The timescale and peak luminosity of these transients depend on the composition of the material after nuclear burning ceases, which determines the local heating rate from nuclear decays and the opacity. Kasen et al. (2013, ApJ, 774, 25) and Tanaka & Hotokezaka (2013, ApJ, 775, 113) pointed out that lanthanides can drastically increase the opacity in these outflows. We use the new general-purpose nuclear reaction network SkyNet to carry out a parameter study of r-process nucleosynthesis for a range of initial electron fractions $Y_e$, initial specific entropies $s$, and expansion timescales $\\tau$. We find that the ejecta is lanthanide-free for $Y_e \\gtrsim 0.22 - 0.30$, depending on $s$ and $\\tau$. The heating rate is insensitive to $s$ and $\\tau$, but certain, larger values of $Y_e$ lead to reduced heating rates, due to individual nuclides dominating the heating. With a...

  8. Effects of culture (China vs. US) and task on perceived hazard: Evidence from product ratings, label ratings, and product to label matching.

    Lesch, Mary F; Rau, Pei-Luen Patrick; Choi, YoonSun

    2016-01-01

    In the current study, 44 Chinese and 40 US college students rated their perceived hazard in response to warning labels and products and attempted to match products with warning labels communicating the same level of hazard. Chinese participants tended to provide lower ratings of hazard in response to labels, but hazard perceived in response to products did not significantly differ as a function of culture. When asked to match a product with a warning label, Chinese participants' hazard perceptions appeared to be better calibrated, than did US participants', across products and labels. The results are interpreted in terms of constructivist theory which suggests that risk perceptions vary depending on the "frame of mind" evoked by the environment/context. Designers of warnings must be sensitive to the fact that product users' cognitive representations develop within a culture and that risk perceptions will vary based on the context in which they are derived. PMID:26360193

  9. Interwell Connectivity and Diagnosis Using Correlation of Production and Injection Rate Data in Hydrocarbon Production

    Jerry L. Jensen; Larry W. Lake; Ali Al-Yousef; Pablo Gentil; Nazli Demiroren

    2005-05-31

    This report details progress on inferring interwell communication from well rate fluctuations. Starting with the procedure of Albertoni and Lake (2003) as a foundation, the goal of the project is to develop further procedures to infer reservoir properties through weights derived from correlations between injection and production rates. A modified method, described in Jensen et al. (2005) and Yousef et al. (2005), and herein referred to as the ''capacitance model'', produces two quantities, {lambda} and {tau}, for each injector-producer well pair. We have focused on the following items: (1) Approaches to integrate {lambda} and {tau} to improve connectivity evaluations. Interpretations have been developed using Lorenz-style and log-log plots to assess heterogeneity. Testing shows the interpretations can identify whether interwell connectivity is controlled by flow through fractures, high-permeability layers, or due to partial completion of wells. Applications to the South Wasson and North Buck Draw Fields show promising results. (2) Optimization of waterflood injection rates using the capacitance model and a power law relationship for watercut to maximize economic return. Initial tests using simulated data and a range of oil prices show the approach is working. (3) Spectral analysis of injection and production data to estimate interwell connectivity and to assess the effects of near-wellbore gas on the results. Development of methods and analysis are ongoing. (4) Investigation of methods to increase the robustness of the capacitance method. These methods include revising the solution method to simultaneously estimate {lambda} and {tau} for each well pair. This approach allows for further constraints to be imposed during the computation, such as limiting {tau} to a range of values defined by the sampling interval and duration of the field data. This work is proceeding. Further work on this project includes the following: (1) Refinement and testing

  10. Continuous biohydrogen production using cheese whey: Improving the hydrogen production rate

    Davila-Vazquez, Gustavo; Cota-Navarro, Ciria Berenice; Razo-Flores, Elias [Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Lomas 4a seccion, C.P. 78216, San Luis Potosi, S.L.P (Mexico); Rosales-Colunga, Luis Manuel; de Leon-Rodriguez, Antonio [Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Lomas 4a seccion, C.P. 78216, San Luis Potosi, S.L.P (Mexico)

    2009-05-15

    Due to the renewed interest in finding sustainable fuels or energy carriers, biohydrogen (Bio-H{sub 2}) from biomass is a promising alternative. Fermentative Bio-H{sub 2} production was studied in a continuous stirred tank reactor (CSTR) operated during 65.6 d with cheese whey (CW) as substrate. Three hydraulic retention times (HRTs) were tested (10, 6 and 4 h) and the highest volumetric hydrogen production rate (VHPR) was attained with HRT of 6 h. Therefore, four organic loading rates (OLRs) at a fixed HRT of 6 h were tested thereafter, being: 92.4, 115.5, 138.6 and 184.4 g lactose/L/d. The highest VHPR (46.61 mmol H{sub 2}/L/h) and hydrogen molar yield (HMY) of 2.8 mol H{sub 2}/mol lactose were found at an OLR of 138.6 g lactose/L/d; a sharp fall in VHPR occurred at an OLR of 184.4 g lactose/L/d. Butyric, propionic and acetic acids were the main soluble metabolites found, with butyric-to-acetic ratios ranging from 1.0 to 2.4. Bacterial community was identified by partial sequence analysis of the 16S rRNA and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that at HRT of 10 h and 6 h were dominated by the Clostridium genus. The VHPR attained in this study is the highest reported value for a CSTR system using CW as substrate with anaerobic sludge as inoculum and represents a 33-fold increase compared to a previous study. Thus, it was demonstrated that continuous fermentative Bio-H{sub 2} production from CW can be significantly enhanced by an appropriate selection of parameters such as HRT and OLR. Enhancements in VHPR are significant because it is a critical parameter to determine the full-scale practical application of fermentation technologies that will be used for sustainable and clean energy generation. (author)

  11. Impact of Declining Proposal Success Rates on Scientific Productivity

    Cushman, Priscilla; Kouveliotou, Chryssa; Lowenthal, James; Peterson, Bradley; Stassun, Keivan G; von Hippel, Ted

    2015-01-01

    Over the last decade proposal success rates in the fundamental sciences have dropped significantly. Astronomy and related fields funded by NASA and NSF are no exception. Data across agencies show that this is not principally the result of a decline in proposal merit (the proportion of proposals receiving high rankings is largely unchanged), nor of a shift in proposer demographics (seniority, gender, and institutional affiliation have all remained unchanged), nor of an increase (beyond inflation) in the average requested funding per proposal, nor of an increase in the number of proposals per investigator in any one year. Rather, the statistics are consistent with a scenario in which agency budgets for competed research are flat or decreasing in inflation-adjusted dollars, the overall population of investigators has grown, and a larger proportion of these investigators are resubmitting meritorious but unfunded proposals. This White Paper presents statistics which support this conclusion, as well as recent resea...

  12. Bounding $f(R)$ gravity by particle production rate

    Capozziello, S; Paolella, M

    2016-01-01

    Several models of $f(R)$ gravity have been proposed in order to address the dark side problem in cosmology. However, these models should be constrained also at ultraviolet scales in order to achieve some correct fundamental interpretation. Here we analyze this possibility comparing quantum vacuum states in given $f(R)$ cosmological backgrounds. Specifically, we compare the Bogolubov transformations associated to different vacuum states for some $f(R)$ models. The procedure consists in fixing the $f(R)$ free parameters and requiring that the Bogolubov coefficients can be correspondingly minimized. In such a way, the particle production is related to the value of the Hubble parameter and then to the given $f(R)$ model. The approach is developed in both metric and Palatini formalism.

  13. Learning control for riser-slug elimination and production-rate optimization for an offshore oil and gas production process

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2014-01-01

    Slugging flow in the offshore oil & gas production attracts lot of attention due to it's limitation of production rate, periodic overload on processing facilities, and even direct cause of emergency shutdown. This work aims at two correlated objectives: (i) Preventing slugging flow; and meanwhile......, (ii) maximizing the production rate at the riser of an offshore production platform, by manipulating a topside choke valve through a learning switching model-free PID controller. The results show good steady-state performance, though a long settling time due to the unknown reference for no slugging...

  14. Correlation of gene expression and protein production rate - a system wide study

    Arvas Mikko

    2011-12-01

    Full Text Available Abstract Background Growth rate is a major determinant of intracellular function. However its effects can only be properly dissected with technically demanding chemostat cultivations in which it can be controlled. Recent work on Saccharomyces cerevisiae chemostat cultivations provided the first analysis on genome wide effects of growth rate. In this work we study the filamentous fungus Trichoderma reesei (Hypocrea jecorina that is an industrial protein production host known for its exceptional protein secretion capability. Interestingly, it exhibits a low growth rate protein production phenotype. Results We have used transcriptomics and proteomics to study the effect of growth rate and cell density on protein production in chemostat cultivations of T. reesei. Use of chemostat allowed control of growth rate and exact estimation of the extracellular specific protein production rate (SPPR. We find that major biosynthetic activities are all negatively correlated with SPPR. We also find that expression of many genes of secreted proteins and secondary metabolism, as well as various lineage specific, mostly unknown genes are positively correlated with SPPR. Finally, we enumerate possible regulators and regulatory mechanisms, arising from the data, for this response. Conclusions Based on these results it appears that in low growth rate protein production energy is very efficiently used primarly for protein production. Also, we propose that flux through early glycolysis or the TCA cycle is a more fundamental determining factor than growth rate for low growth rate protein production and we propose a novel eukaryotic response to this i.e. the lineage specific response (LSR.

  15. Optimal integrated maintenance/production policy for randomly failing systems with variable failure rate

    Zied, Hajej; Dellagi, Sofiene; Rezg, Nidhal

    2011-01-01

    Abstract This paper deals with combined production and maintenance plans for a manufacturing system satisfying a random demand. We first establish an optimal production plan which minimizes the average total inventory and production cost. Secondly, using this optimal production plan, and taking into account the deterioration of the machine according to its production rate, we derive an optimal maintenance schedule which minimizes the maintenance cost. A numerical example illustrate...

  16. In Situ Production of Chlorine-36 in the Eastern Snake River Plain Aquifer, Idaho: Implications for Describing Ground-Water Contamination Near a Nuclear Facility

    The purpose of this report is to describe the calculated contribution to ground water of natural, in situ produced 36Cl in the eastern Snake River Plain aquifer and to compare these concentrations in ground water with measured concentrations near a nuclear facility in southeastern Idaho. The scope focused on isotopic and chemical analyses and associated 36Cl in situ production calculations on 25 whole-rock samples from 6 major water-bearing rock types present in the eastern Snake River Plain. The rock types investigated were basalt, rhyolite, limestone, dolomite, shale, and quartzite. Determining the contribution of in situ production to 36Cl inventories in ground water facilitated the identification of the source for this radionuclide in environmental samples. On the basis of calculations reported here, in situ production of 36Cl was determined to be insignificant compared to concentrations measured in ground water near buried and injected nuclear waste at the INEEL. Maximum estimated 36Cl concentrations in ground water from in situ production are on the same order of magnitude as natural concentrations in meteoric water

  17. Production rate of Morus Alba pollen grains in an abandoned M. Alba plantation

    Kiyonaga, Jota

    2016-01-01

    As a basic study for pollen analysis, the production rate of Morus alba (white mulberry) pollen grains in an abandoned M. alba plantation was determined over a three-year period from 1997 to 1999. The number of pollen grains per male catkin was assessed and the fall rate of male catkins was measured using five litter traps. The mean production rate was 2.6 × 10^ grains ha^yr^ (range = 2.2-3.4 × 10^ grains ha^yr^). This is near the lower end of the range of pollen production rates that have be...

  18. Engineering Mathematical Analysis Method for Productivity Rate in Linear Arrangement Serial Structure Automated Flow Assembly Line

    Tan Chan Sin

    2015-01-01

    Full Text Available Productivity rate (Q or production rate is one of the important indicator criteria for industrial engineer to improve the system and finish good output in production or assembly line. Mathematical and statistical analysis method is required to be applied for productivity rate in industry visual overviews of the failure factors and further improvement within the production line especially for automated flow line since it is complicated. Mathematical model of productivity rate in linear arrangement serial structure automated flow line with different failure rate and bottleneck machining time parameters becomes the basic model for this productivity analysis. This paper presents the engineering mathematical analysis method which is applied in an automotive company which possesses automated flow assembly line in final assembly line to produce motorcycle in Malaysia. DCAS engineering and mathematical analysis method that consists of four stages known as data collection, calculation and comparison, analysis, and sustainable improvement is used to analyze productivity in automated flow assembly line based on particular mathematical model. Variety of failure rate that causes loss of productivity and bottleneck machining time is shown specifically in mathematic figure and presents the sustainable solution for productivity improvement for this final assembly automated flow line.

  19. Entropy Production Rate Changes in Lysogeny/Lysis Switch Regulation of Bacteriophage Lambda

    According to the chemical kinetic model of lysogeny/lysis switch in Escherichia coli (E. coli) infected by bacteriophage λ, the entropy production rates of steady states are calculated. The results show that the lysogenic state has lower entropy production rate than lytic state, which provides an explanation on why the lysogenic state of λ phage is so stable. We also notice that the entropy production rates of both lysogenic state and lytic state are lower than that of saddle-point and bifurcation state, which is consistent with the principle of minimum entropy production for living organism in nonequilibrium stationary state. Subsequently, the relations between CI and Cro degradation rates at two bifurcations and the changes of entropy production rate with CI and Cro degradation are deduced. The theory and method can be used to calculate entropy change in other molecular network. (interdisciplinary physics and related areas of science and technology)

  20. Manufacturing production and non-agricultural employment rate in South Africa: Time series analysis

    Paul-Francois Muzindutsi; Magdeline M. Maepa

    2014-01-01

    South African is faced with a high unemployment rate; however, the country's manufacturing sector is one of the sectors that have been linked with job creation. Nevertheless, the growth in manufacturing production may not increase employment opportunities if this sector continues to shift to technology-intensive methods of production, which displace labour. This study uses a vector autoregressive (VAR) model to estimate the interaction between manufacturing production and the employment rate ...

  1. Studies of jet production rates in e+e- annihilation at Ecm=29 GeV

    Production rates of multijet hadronic final states are studied in e+e- annihilation at 29 GeV center of mass energy. QCD shower model calculations with exact first order matrix element weighting at the first gluon vertex are capable of reproducing the observed multijet event rates over a large range of jet pair masses. The method used to reconstruct jets is well suited for directly comparing experimental jet rates with parton rates calculated in perturbative QCD. Evidence for the energy dependence of αs is obtained by comparing the observed production rates of 3-jet events with results of similar studies performed at higher center of mass energies. (orig.)

  2. 78 FR 41129 - Market Test of Experimental Product - International Merchandise Return Service-Non-Published Rates

    2013-07-09

    ... will begin a market test of its International Merchandise Return Service (IMRS) Non-published Rate (NPR... of Experimental Product -- International Merchandise Return Service--Non-Published Rates AGENCY: U.S... International Merchandise Return Service--Non-Published Rates in accordance with statutory requirements....

  3. Product adjustments: A firm-level analysis of the impact of a real exchange rate shock

    Moxnes, Andreas; Ulltveit-Moe, Karen-Helene

    2010-01-01

    Using a new and extensive micro data set we investigate the impact of a change in international competitive pressure following a real exchange shock on multi-product firms’ product mix. We only find weak evidence for the core competencies hypothesis, according to which, we would expect the exposed firms to reduce their product portfolio in response to the shock. But firms exposed to the shock significantly reduced their rate of product churning, relative to the control group of nonexposed fir...

  4. Dose rate distribution for products irradiated in a semi-industrial irradiation plant. 1st stage

    The model of the bulk product absorbed dose rate distribution in a semi industrial irradiation plant is presented. In this plant the products are subject to a dynamic irradiation process: single-plaque, single-direction, four-passes. The additional two passes, also one on each side of the plaque, serve to minimize the lateral dose variation as well as the depth-dose non-uniformity. The first stage of this model takes only into account the direct absorbed dose rate; the model outputs are the depth-dose distribution and the lateral-dose distribution. The calculated absorbed dose in the bulk product and its uniformity-ratio after the dynamic irradiation process for different products is compared. The model results are in good agreement with the experimental measurements in a bulk of irradiated product; and the air absorbed dose rate in the irradiation chamber behind the product subject to the dynamic irradiation process. (author)

  5. A quantitative model of water radiolysis and chemical production rates near radionuclide-containing solids

    Dzaugis, Mary E.; Spivack, Arthur J.; D'Hondt, Steven

    2015-10-01

    We present a mathematical model that quantifies the rate of water radiolysis near radionuclide-containing solids. Our model incorporates the radioactivity of the solid along with the energies and attenuation properties for alpha (α), beta (β), and gamma (γ) radiation to calculate volume normalized dose rate profiles. In the model, these dose rate profiles are then used to calculate radiolytic hydrogen (H2) and hydrogen peroxide (H2O2) production rates as a function of distance from the solid-water interface. It expands on previous water radiolysis models by incorporating planar or cylindrical solid-water interfaces and by explicitly including γ radiation in dose rate calculations. To illustrate our model's utility, we quantify radiolytic H2 and H2O2 production rates surrounding spent nuclear fuel under different conditions (at 20 years and 1000 years of storage, as well as before and after barrier failure). These examples demonstrate the extent to which α, β and γ radiation contributes to total absorbed dose rate and radiolytic production rates. The different cases also illustrate how H2 and H2O2 yields depend on initial composition, shielding and age of the solid. In this way, the examples demonstrate the importance of including all three types of radiation in a general model of total radiolytic production rates.

  6. Enhancing product quantity by controlling the specific growth rate of Pichia pastoris expressing human serum albumin

    Hama, Adel; Eyer, Kurt

    2011-01-01

    Establish a fed-batch process to culture a Pichia pastoris strain producing a recombinant protein (hSA), highlighting the relationship between the specific growth rate and the protein quality, as well as seeking for enhanced productivity.

  7. Relationship between Selected Properties of Starchy Vegetables on Grating and Slicing Production Rate

    Lok Chung Yee

    2012-01-01

    Full Text Available Prediction on the output of grating and slicing of starchy vegetables are important prior to design or develop the particular food plant. The production rate of grating and slicing products could be affected by the properties of starchy vegetables. In this study, two selected properties which hardness and moisture content are studied. Hardness of selected starchy vegetables was measured using a destructive testing method of texture analyzer. A testing machine of the texture analyzer applied a specific blade to shear the vegetables and automatically generate data. The objective of this study was to determine the relationship between starchy vegetables hardness and moisture content which influenced the production rate in grating and slicing products. The selected starchy vegetables used for this study were white potato, sweet potato, tapioca and yam. The maximum hardness was computed and analyzed using the texture analyzer. It was found that the maximum hardness of white potato, yam, sweet potato and tapioca were 6.67, 12.01, 16.98 and 20.08 kg respectively. It was determined that white potato had the highest moisture content among the vegetables, which was 78.14%. In conclusion, the lower value of hardness and higher value of moisture content are significantly correlated to higher production rate of grating and slicing products. Results presented may help the food industry to initially predict the production rate of agricultural products such as food chips and finger products."

  8. Firm Productivity, Exchange Rate Movements, Sources of Finance and Export Orientation

    Demir, Firat; Caglayan, Mustafa

    2012-01-01

    We investigate the level and volatility effects of real exchange rates on the productivity growth of manufacturing firms with heterogeneous access to debt, and domestic and foreign equity markets in Turkey. We find that while exchange rate volatility affects productivity growth negatively, having access to foreign or domestic equity, or debt markets does not alleviate these effects. Furthermore, foreign owned or publicly traded companies do not appear to perform significantly better than the ...

  9. A quantitative model of water radiolysis and chemical production rates near radionuclide-containing solids

    We present a mathematical model that quantifies the rate of water radiolysis near radionuclide-containing solids. Our model incorporates the radioactivity of the solid along with the energies and attenuation properties for alpha (α), beta (β), and gamma (γ) radiation to calculate volume normalized dose rate profiles. In the model, these dose rate profiles are then used to calculate radiolytic hydrogen (H2) and hydrogen peroxide (H2O2) production rates as a function of distance from the solid–water interface. It expands on previous water radiolysis models by incorporating planar or cylindrical solid–water interfaces and by explicitly including γ radiation in dose rate calculations. To illustrate our model's utility, we quantify radiolytic H2 and H2O2 production rates surrounding spent nuclear fuel under different conditions (at 20 years and 1000 years of storage, as well as before and after barrier failure). These examples demonstrate the extent to which α, β and γ radiation contributes to total absorbed dose rate and radiolytic production rates. The different cases also illustrate how H2 and H2O2 yields depend on initial composition, shielding and age of the solid. In this way, the examples demonstrate the importance of including all three types of radiation in a general model of total radiolytic production rates. - Highlights: • Our model quantifies radiolytic chemical production near solid–water interfaces. • The model accounts for chemical production by α, β and γ radiation. • The model is applicable to both planar and curved surfaces. • Relative production by α, β and γ radiation strongly depends on solid composition. • We apply the model to young and old spent nuclear fuel, with and without cladding

  10. Effects of time and other variables on fission product release rates

    The releases of krypton and cesium from highly irradiated LWR fuel have been examined in detail. The main interest has been the effect of time on the rate of release and the effects of heatup and cooldown cycles. The minute-by-minute release rates for fission product 85Kr from commercial fuel irradiated in the H.B. Robinson PWR are shown. The release rate, fraction per minute, is calculated in the same manner as release rates given in NUREG-0772; the fission gas, cesium, and iodine release rate curve from that report is also shown

  11. Enhanced bit rate-distance product impulse radio ultra-wideband over fiber link

    Rodes Lopez, Roberto; Jensen, Jesper Bevensee; Caballero Jambrina, Antonio; Yu, Xianbin; Pivnenko, Sergey; Tafur Monroy, Idelfonso

    2010-01-01

    We report on a record distance and bit rate-wireless impulse radio (IR) ultra-wideband (UWB) link with combined transmission over a 20 km long fiber link. We are able to improve the compliance with the regulated frequency emission mask and achieve bit rate-distance products as high as 16 Gbit/s·m....

  12. A comparison of cardiac rate-pressure product and pressure-rate quotient in healthy and medically compromised patients.

    Campbell, R L; Langston, W G

    1995-08-01

    Healthy and medically compromised patients were studied to compare blood pressure and heart rate changes in response to stress of routine dental extractions performed while they were under local anesthesia. Thirty-nine patients divided into American Society of Anesthesiologists (ASA) I and II groups were noninvasively monitored every 5 minutes. Systolic, diastolic, and mean arterial pressures and heart rate were recorded. Rate pressure products (RPP) and pressure rate (PRQ) quotients were calculated and compared in each group. Significant results were measures of RPP greater than 12,000 and PRQ less than one. Of the 24 patients in the ASA I category, 50% demonstrated elevated RPP values, but only two of 24 had coincidental PRQ abnormalities. Of the 15 patients in the ASA II category, 80% demonstrated elevated RPP values, but two of 15 had coincidental PRQ abnormalities. Patients in the ASA II category had a higher incidence of RPP and PRQ abnormalities, as was expected. However, it is not known which of these two measures is a more sensitive indicator of increased risk associated with stimulation of the sympathetic-adrenergic axis during oral surgery performed with patients under local anesthesia. Correlation studies with continuous Holter monitoring for ST-T wave changes on electrocardiography are forthcoming. PMID:7552876

  13. Automated Production Flow Line Failure Rate Mathematical Analysis with Probability Theory

    Tan Chan Sin

    2014-12-01

    Full Text Available Automated lines have been widely used in the industries especially for mass production and to customize product. Productivity of automated line is a crucial indicator to show the output and performance of the production. Failure or breakdown of station or mechanisms is commonly occurs in the automated line in real condition due to the technological and technical problem which is highly affect the productivity. The failure rates of automated line are not express or analyse in terms of mathematic form. This paper presents the mathematic analysis by using probability theory towards the failure condition in automated line. The mathematic express for failure rates can produce and forecast the output of productivity accurately

  14. Precommitment and random exchange rates in symmetric duopoly: a new theory of multinational production

    David Nickerson; Marsha Courchane; Venkatraman Sadanand

    1990-01-01

    Recent volatility in real exchange rates has renewed interest in the nature of multinational firms. One increasingly common phenomenon involves the foreign sourcing of production, in which certain domestic firms choose to produce part or all of their product abroad and then export the commodity for domestic sale. Multinational production has been rationalized on the basis of inherent asymmetries between firms, such as the possession of certain firm-specific assets or differences between firms...

  15. Integrated Strategic Planning of Global Production Networks and Financial Hedging under Uncertain Demands and Exchange Rates

    Achim Koberstein; Elmar Lukas; Marc Naumann

    2013-01-01

    In this paper, we present a multi-stage stochastic programming model that integrates financial hedging decisions into the planning of strategic production networks under uncertain exchange rates and product demands. This model considers the expenses of production plants and the revenues of markets in different currency areas. Financial portfolio planning decisions for two types of financial instruments, forward contracts and options, are represented explicitly by multi-period decision variabl...

  16. Atomic hydrogen production rates for comet P/Halley from observations with Dynamics Explorer I

    Craven, J. D.; Frank, L. A.

    1987-01-01

    Newly analyzed observations of the Dynamics Explorer I (DE1), launched on August 3, 1981, were used to determine the hydrogen production rate for Comet Halley at heliocentric distances, r, less than about 1.5 AU from measurements of the total Lyman-alpha flux at earth due to the cometary neutral hydrogen distribution. The production rates, determined as a function of r, were found to be consistent with in situ measurements from the Giotto and Vega spacecraft. The calculated rates are also consistent with remote observations using two sounding rockets and with the Pioneer-Venus and IUE spacecraft.

  17. The Rate-Distortion Function for Product of Two Sources with Side-Information at Decoders

    Watanabe, Shun

    2011-01-01

    This paper investigates a lossy source coding problem in which two decoders can access their side-information respectively. The correlated sources are a product of two component correlated sources, and we exclusively investigate the case such that each component is degraded. We show the rate-distortion function for that case, and give the following observations. When the components are degraded in matched order, the rate distortion function of the product sources is equal to the sum of the component-wise rate distortion functions. On the otherhand, the former is strictly smaller than the latter when the component sources are degraded in mismatched order.

  18. Norwegian resource policy: The production rate for Norwegian petroleum resources; Norsk ressurspolitikk: Utvinningstempoet for norske petroleumsressurser

    Schreiner, P.

    1995-12-31

    Petroleum activities have become a large industry in Norway. This has led to extensive changes in Norwegian economy and society. In the public debate on this activity there has been little discussion of what would be the most profitable production rate. However, it is generally agreed that the great wealth implied by the petroleum resources must be managed in ways suitable to both present and coming generations. This report discusses the production rate based on the following questions: (1) How high can the production rate be before the petroleum activities and the expenditure of the income from them influence the remaining Norwegian economy too strongly? (2) How much of this wealth should reasonably be used by present generations and how much should be left for future generations? There is much to gain from a high tempo and from relocating some of the petroleum wealth. The possibilities of influencing the production rate are mainly connected with the allotments of production licences. The consequences of uncertainties in the petroleum activities for the choice of exploitation tempo are unclear. The environment is not much affected by the production rate. The contractor activity has become Norway`s largest industry. 42 refs., 14 figs., 2 tabs.

  19. Hydrogen and hydroxyl production rates of Comet Tago-Sato-Kosaka /1969 IX/

    Keller, H. U.; Lillie, C. F.

    1978-01-01

    Comet Tago-Sato-Kosaka (1969 IX) was observed with the ultraviolet photometers on OAO 2 from January 16.41 to January 29.89, 1970, while its heliocentric distance increased from 0.78 to 1.03 AU. The production rates of hydrogen and hydroxyl are derived from Lyman-alpha (1216 A) and OH (0-0) band (3090 A) emission. The variations of the hydrogen and hydroxyl production ran parallel to one another, while their ratio was about 3:1. These results are consistent with the assumption that vaporization of water ice controlled the production rate of gas during this interval. The hydrogen production rates of four nonperiodic comets are compared.

  20. Development of Copper Corrosion Products and Relation between Surface Appearance and Corrosion Rate

    Lan, Tran Thi Ngoc; Binh, Nguyen Thi Thanh [Vietnam National University, Ho Chi Minh (Viet Nam); Tru, Nguyen Nhi [Vietnam Institute for Tropical Technology and Environmental Protection, Ho Chi Minh (Viet Nam); Yoshino, Tsujino [Osaka Prefecture, Osaka (Japan); Yasuki, Maeda [Osaka Prefecture University, Osaka (Japan)

    2008-04-15

    Copper was exposed unsheltered and sheltered in four humid tropical sites, representing urban, urban-industrial, urban-marine and rural environments. The corrosion rates and the sequence of corrosion product formation are presented and discussed in relation with climatic and atmospheric pollution parameters. Chemical compositions of corrosion products were found to depend on environments and duration of exposure. In all environments, cuprite was the predominating corrosion product that formed first and continuously increased during the exposure. Among the sulphur-containing corrosion products, posnjakite and brochantite were more frequently found and the first formed earlier. Nantokite was the most common chlorine-containing products for most cases, except the high-chloride environment, where atacamite was detected instead. The corrosion rate of copper was well indicated by the colour of patina. The red-purple colour corresponded to the high corrosion rate and the greenish grey colour corresponded to the low corrosion rate. Corrosion rate of sheltered copper in urban-marine environment increased with the exposure time.

  1. A study of the release rate of corrosion products for nuclear SG tubing

    Out-of-core radiation fields mainly are caused by activated corrosion product released from nuclear heat supply system. It is very important to minimize the generation of radioactive corrosion products which become a radiation source, in order to meet the needs of operation and maintenance. A study was conducted on determining the general corrosion rate and metal release rate for Inconel 690 (Japan), Inconel 690 (China), Inconel 600 and Incoloy 800 tubes on the primary water side of nuclear power plant simulation. The results show that the release rates of corrosion products of Alloy 690 on the primary water side is very low and that they decrease with the increase of chromium content in the alloys. (8 refs, 9 figs., 4 tabs.)

  2. Rate of germanium-isotope production by background processes in the SAGE experiment

    Data on a direct determination of systematic uncertainties caused by the background production of germanium isotopes in the radiochemical SAGE experiment measuring the solar-neutrino flux are analyzed. The result obtained for the rate of 68Ge production is 6.5(1±1.0) times greater than the expected one; the rate of 69Ge production does not exceed preliminary estimates. The above result for 68Ge corresponds to the systematic uncertainty that is caused by the interaction of cosmic-ray muons and which is equal to 5.8% (4.5 SNU) at a solar-neutrino-capture rate of 77.0 SNU. An experiment is proposed that would test the effect of cosmic-ray muon influence on the SAGE systematic uncertainty and which would be performed at the location of the underground scintillation telescope facilities of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences)

  3. On-line tritium production and heat deposition rate measurements at the Lotus facility

    Integral tritium production and heat deposition measurement in a prototype fusion blanket would enable verification of the computational codes and the data based employed for the calculations. A large number of tritium production rate measurements have been reported for different type of blankets, whereas the direct heat deposition due to the mixed radiation field in the fusion environment, is still in its infancy. In order to ascertain the kerma factors and the photon production libraries, suitable techniques must be developed to directly measure the nuclear heat deposition rates in the materials required for the fusion systems. In this context, at the Lotus facility, we have developed an extremely efficient double ionizing chamber, for the on-line tritium production measurements and employed a pure graphite calorimeter to measure the nuclear heat deposition due to the mixed radiation field of the 14 MeV, Haefely neutron generator. This paper presents both systems and some of the recent measurements. (authors). 8 refs., 13 figs

  4. Fines stabilizing agent reduces production decline rates in steam injected wells

    Castillo de Castillo, Milagros; Fernandez Andrades, Jarvi [PDVSA - Petroleos de Venezuela S.A., Caracas (Venezuela); Navarro Cornejo, Willian; Curtis, James [BJ Services do Brasil Ltda., RJ (Brazil)

    2004-07-01

    The Bachaquero Lago heavy oil field, located in Lake Maracaibo, Venezuela, with an area of 9800 ha, in which more than 1800 wells have been drilled. The Lagunillas formation in this field is a mature, clastic, unconsolidated sandstone of Miocene age with good permeability. Clays are present, in laminated form or dispersed within the productive sandstones. Heavy oil, less than 12 deg API, is produced by cyclic steam injection. Wells are completed with cased-hole gravel packs to prevent sand and fines production. Rapid production decline rates are typically observed after the steam injection cycles, due to fines migration and plugging of the reservoir and gravel pack. This paper describes the methodology used to treat the wells with a fines stabilizing agent during the steam injection cycles in order to successfully reduce the subsequent production decline rate. Results from a multi-well pilot project are presented and analyzed. (author)

  5. Price of recreational products and the exchange rate: an empirical investigation on US data

    Cellini, Roberto; Alessandro PAOLINO

    2007-01-01

    The paper analyses the cointegration relationships and the causal links between the exchange rate of the US Dollar, on the one side, and different price indices of US products on the other side. Data are of monthly frequency and cover a period of two or three decades. We show that the exchange rate cointegrate with the Consumer Price Index and with the prices indices of several agricultural, manufactured and service goods; moreover a one-direction causal link is present, running from price ...

  6. Propagation of Localization Optimal Entropy Production and Convergence rates for the Central Limit Theorem

    Carlen, E

    2011-01-01

    We prove for the rescaled convolution map $f\\to f\\circledast f$ propagation of polynomial, exponential and gaussian localization. The gaussian localization is then used to prove an optimal bound on the rate of entropy production by this map. As an application we prove the convergence of the CLT to be at the optimal rate $1/\\sqrt{n}$ in the entropy (and $L^1$) sense, for distributions with finite 4th moment.

  7. Pressure effect on rate of production of glucose-equivalent in plant cells

    Anirban Panda; Surjendu Bhattacharyya; Sambhu N Datta

    2009-07-01

    The rate of glucose equivalent production in C4 green plants is investigated as a function of the intercellular partial pressure of CO2, so as to find the precise physical chemistry of photosynthesis. Expressions are first formulated for the dependence of photochemical efficiency and of rubisco activation on pressure. Then a pressure-dependent rate law is derived. The latter is successfully tested for two specific C4 plants, namely, Panicum antidotale and Panicum coloratum.

  8. Rerouting Cellular Electron Flux To Increase the Rate of Biological Methane Production

    Catlett, Jennie L.; Ortiz, Alicia M.; Buan, Nicole R.

    2015-01-01

    Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen electron trans...

  9. A production inventory model with exponential demand rate and reverse logistics

    Ritu Raj

    2014-08-01

    Full Text Available The objective of this paper is to develop an integrated production inventory model for reworkable items with exponential demand rate. This is a three-layer supply chain model with perspectives of supplier, producer and retailer. Supplier delivers raw material to the producer and finished goods to the retailer. We consider perfect and imperfect quality products, product reliability and reworking of imperfect items. After screening, defective items reworked at a cost just after the regular manufacturing schedule. At the beginning, the manufacturing system starts produce perfect items, after some time the manufacturing system can undergo into “out-of-control” situation from “in-control” situation, which is controlled by reverse logistic technique. This paper deliberates the effects of business strategies like optimum order size of raw material, exponential demand rate, production rate is demand dependent, idle times and reverse logistics for an integrated marketing system. Mathematica is used to develop the optimal solution of production rate and raw material order for maximum expected average profit. A numerical example and sensitivity analysis is illustrated to validate the model.

  10. Species-level variability in extracellular production rates of reactive oxygen species by diatoms

    Schneider, Robin; Roe, Kelly; Hansel, Colleen; Voelker, Bettina

    2016-03-01

    Biological production and decay of the reactive oxygen species (ROS) hydrogen peroxide (H2O2) and superoxide (O2-) likely have significant effects on the cycling of trace metals and carbon in marine systems. In this study, extracellular production rates of H2O2 and O2- were determined for five species of marine diatoms in the presence and absence of light. Production of both ROS was measured in parallel by suspending cells on filters and measuring the ROS downstream using chemiluminescence probes. In addition, the ability of these organisms to break down O2- and H2O2 was examined by measuring recovery of O2- and H2O2 added to the influent medium. O2- production rates ranged from undetectable to 7.3 x 10-16 mol cell-1 hr-1, while H2O2 production rates ranged from undetectable to 3.4 x 10-16 mol cell-1 hr-1. Results suggest that extracellular ROS production occurs through a variety of pathways even amongst organisms of the same genus. Thalassiosira spp. produced more O2- in light than dark, even when the organisms were killed, indicating that O2- is produced via a passive photochemical process on the cell surface. The ratio of H2O¬2 to O2- production rates was consistent with production of H2O2 solely through dismutation of O2- for T. oceanica, while T. pseudonana made much more H2O2 than O2 . T. weissflogii only produced H2O2 when stressed or killed. P. tricornutum cells did not make cell-associated ROS, but did secrete H2O2-producing substances into the growth medium. In all organisms, recovery rates for killed cultures (94-100% H2O2; 10-80% O2-) were consistently higher than those for live cultures (65-95% H2O2; 10-50% O2-). While recovery rates for killed cultures in H2O2 indicate that nearly all H2O2 was degraded by active cell processes, O2- decay appeared to occur via a combination of active and passive processes. Overall, this study shows that the rates and pathways for ROS production and decay vary greatly among diatom species, even between those that are

  11. FORECASTING OF COMPETITIVE PRODUCT PRICE WITH DUE ACCOUNT OF QUALITY RATE

    I. V. Ваrysevich

    2011-01-01

    Terminology of  such concepts as «competitiveness» and «competitive price» is specified and capacity of a potential market segment for positioning innovative production is estimated in the paper. The paper analyzes a method for estimation of a quality rate on the basis of product consumer attractiveness. An improved  methodology for forecasting of a competitive price has been put on an evaluation test  while using actual data.  

  12. ANALYSIS OF CORRELATION BETWEEN THE UNEMPLOYMENT RATE AND GROSS DOMESTIC PRODUCT IN THE EUROPEAN UNION

    Cioca Ionela Cornelia

    2013-01-01

    Vacancies, unemployment, wage levels and labor costs do not only affect a country's economy by lowering the Gross Domestic Product, but every person’s life. The purpose of this paper is to analyze the Gross Domestic Product and unemployment rate in the European countries for the period 2005-2011. To perform the analysis, official data from Eurostat, National Statistical Institute and the National Agency for Employment in Romania were taken. The research objectives are to analyze the two indic...

  13. Subterranean production of neutrons, $^{39}$Ar and $^{21}$Ne: Rates and uncertainties

    Šrámek, Ondřej; Stevens, Lauren; William F. McDonough; Mukhopadhyay, Sujoy; Peterson, R. J.

    2015-01-01

    Accurate understanding of the subsurface production of radionuclide $^{39}$Ar rate is necessary for argon dating techniques and noble gas geochemistry of the shallow and the deep Earth, and is also of interest to the WIMP dark matter experimental particle physics community. Our new calculations of subsurface production of neutrons, $^{21}$Ne, and $^{39}$Ar take advantage of the best available tools of nuclear physics to obtain reaction cross sections and spectra (TALYS) and to evaluate neutro...

  14. The rate of visitation by Amazilia fimbriata (Apodiformes: Trochilidae) influences seed production in Tillandsia stricta (Bromeliaceae)

    Caio C.C. Missagia; Maria Alice S. Alves

    2015-01-01

    Legitimate flowers visitors pollinate the flower during the visit and thus influence the production of fruits and seeds. We tested whether the visitation rate of potential pollinators is associated with the amount of seeds per fruit produced by the self-compatible bromeliad Tillandsia stricta (Bromeliaceae). We determined whether hummingbirds are legitimate visitors by testing for a correlation between visits and pollination (seed production) at the Guapiaçú Ecological Reserve (Reserva Ecológ...

  15. Relationship between Selected Properties of Starchy Vegetables on Grating and Slicing Production Rate

    Lok Chung Yee; M. K.S. Mazlina; B. T.H. Tuah

    2012-01-01

    Prediction on the output of grating and slicing of starchy vegetables are important prior to design or develop the particular food plant. The production rate of grating and slicing products could be affected by the properties of starchy vegetables. In this study, two selected properties which hardness and moisture content are studied. Hardness of selected starchy vegetables was measured using a destructive testing method of texture analyzer. A testing machine of the texture analyzer applied a...

  16. Evaluation of fission product release rates during postulated core meltdown accidents

    An investigation of fission product release rates under severe accident conditions is presented for a pressurized water reactor with a large dry containment. In the calculation of fission product source terms, the numeical scheme by using core node temperatures during heatup and meltdown is introduced and incorporated into the MARCH code. The results indicated that the significant differences between the numerical integration method and WASH-1400 method are observed, especially Ru and La release categories. (Author)

  17. Model for GCR-particle fluxes in stony meteorites and production rates of cosmogenic nuclides

    Reedy, R.C.

    1984-01-01

    A model is presented for the differential fluxes of galactic-cosmic-ray (GCR) particles with energies above 1 MeV inside any spherical stony meteorite as a function of the meteorite's radius and the sample's depth. This model is based on the Reedy-Arnold equations for the energy-dependent fluxes of GCR particles in the moon and is an extension of flux parameters that were derived for several meteorites of various sizes. This flux is used to calculate the production rates of many cosmogenic nuclides as a function of radius and depth. The peak production rates for most nuclides made by the reactions of energetic GCR particles occur near the centers of meteorites with radii of 40 to 70 g cm/sup -2/. Although the model has some limitations, it reproduces well the basic trends for the depth-dependent production of cosmogenic nuclides in stony meteorites of various radii. These production profiles agree fairly well with measurements of cosmogenic nuclides in meteorites. Some of these production profiles are different than those calculated by others. The chemical dependence of the production rates for several nuclides varies with size and depth. 25 references, 8 figures.

  18. IMPACT OF MARKET-DETERMINED EXCHANGE RATES ON RICE PRODUCTION AND IMPORT IN NIGERIA

    Aliyu Aishat Ammani

    2013-10-01

    Full Text Available Rice is an economically important food security crop, cultivated in almost all of Nigeria’s 36 States. Nigeria spends more than 356 billion naira (2.24 billion US dollars annually on rice import. This paper set out to analyze the trend in rice production, productivity, import, value of import and consumption that follows the adoption of the Structural Adjustment Programme (SAP in Nigeria, with emphasis on the effects of exchange rate (ER deregulation on domestic rice production and rice imports over the period 1986-2010. Relevant time series data were collected and used. A semi-log growth rate model and 2simple linear regression models were developed and estimated. Highlights of the findings include (i accelerated rate of growth in rice production (Instantaneous Growth Rate (IGR 2.2%; Cumulative Growth Rate (CGR 2.2%; rice hectarage (IGR 3.7%; CGR 3.8%; rice importation (IGR 8.5%; CGR8.9%; expenditure on rice importation (IGR 10.6%; CGR 11.2% and rice consumption (IGR 3.4%; CGR 3.5% alongside a significant deceleration in rice yield (IGR -1.4%; CGR -201.4% (ii The observed significant increase in domestic rice production cannot be confidently attributed to ER deregulation alone because it does not lead to a decrease in rice importation into Nigeria. (iii The significant increase in domestic rice importation as observed contradicts a priori expectation that ER deregulation will lead to significant decrease in rice importation. The study concluded that free market approach alone cannot stimulate local agricultural production in countries where farmers producing under low-technology-agriculture are put in direct competition with farmers from advancedtechnology-agriculture; hence governments need to restrict importation to protect local producers.

  19. Species-Level Variability in Extracellular Production Rates of Reactive Oxygen Species by Diatoms

    Schneider, Robin J.; Roe, Kelly L.; Hansel, Colleen M.; Voelker, Bettina M.

    2016-01-01

    Biological production and decay of the reactive oxygen species (ROS) hydrogen peroxide (H2O2) and superoxide (O2-) likely have significant effects on the cycling of trace metals and carbon in marine systems. In this study, extracellular production rates of H2O2 and O2- were determined for five species of marine diatoms in the presence and absence of light. Production of both ROS was measured in parallel by suspending cells on filters and measuring the ROS downstream using chemiluminescence pr...

  20. Species-Level Variability in Extracellular Production Rates of Reactive Oxygen Species by Diatoms

    Schneider, Robin J.; Roe, Kelly L.; Hansel, Colleen M.; Voelker, Bettina M.

    2016-01-01

    Biological production and decay of the reactive oxygen species (ROS) hydrogen peroxide (H2O2) and superoxide (O 2 - ) likely have significant effects on the cycling of trace metals and carbon in marine systems. In this study, extracellular production rates of H2O2 and O 2 - were determined for five species of marine diatoms in the presence and absence of light. Production of both ROS was measured in parallel by suspending cells on filters and measuring the ROS downstream using chemiluminescen...

  1. Efficient methane production from Lipid-Rich Wastewater in high-rate anaerobic treatment

    Anaerobic digestion allows, simultaneously, wastewater treatment and production of biogas, a renewable energy source. The energy yield of this process is higher for more reduced compounds, such as long chain fatty acids (LCFA), the main products of lipids hydrolysis. However, LCFA conversion to biogas is not always complete, and tends to decrease with the increase of the organic loading rate applied (OLR). Recent results obtained in our research group showed that efficient methane production from lipid-rich wastewater can be accomplished if acclimation of the inoculum is performed through discontinuous or pulsed feeding of fat. (Author)

  2. "Effects of agitation rate on the growth of Mycena SP and production of antifungal agents "

    Vahidi H

    2002-07-01

    Full Text Available Impeller speed or agitation rate plays a significant role in the growth of microorganism especially basidiomycetes and production of bioactive compounds via transfer of oxygen and mass. In this investigation the efferent impeller speeds on morphology, biomass concentration and production of bioactive compounds with antifungal activity were studied using a 5-liter fermenter. It was found that use of different impeller speeds (300 , 450 and 600 rpm resulted in various growth pattern and productivity. Impeller speed of 600 rpm gave a tow biomass concentration and low production of antifungal agent and the best result was obtained when impeller speed was adjusted to 450 rpm. Biomass concentration and productivity in the case of 300 rpm was less than that of 450 but higher than of 600 rpm.

  3. The effect of soil moisture on nitrous oxide production rates in large enclosed ecosystems

    van Haren, J.; Colodner, D.; Lin, G.; Murthy, R.

    2001-12-01

    On land, nitrous oxide (N2O) is mainly produced in soils by bacterial processes such as nitrification and denitrification. Once in the atmosphere N2O contributes to the greenhouse effect and stratospheric ozone destruction. Nitrification and denitrification are strongly dependent on soil moisture content, amongst other soil parameters. At Biosphere 2 Center we have begun to test the utility of meso-scale closed systems for understanding the relationship between soil properties and trace gas production at larger scales. We investigated the relationship between soil moisture content and soil N2O efflux in two large experimental closed systems (Tropical Rainforest (TR) and Intensive Forestry (IF) Mesocosms) at Biosphere 2 Center. N2O was measured every hour with an automated GC system. The daily N2O production rate was calculated as the rate of increase of N2O during the daytime, when the mesocosm was materially closed. We furthermore measured N2O and nitrate concentrations in the soil, as well as nitrate and N2O production rates in local areas. In the Rainforest Mesocosm, we found a very reproducible relationship between soil moisture content and N2O efflux, including the transient spikes in production rate upon wetting. In the Forestry Mesocosm the relation between soil moisture and N2O efflux was less clearcut.

  4. Reduced rates and alternatives to methyl bromide for snapdragon production in Florida

    A field trial was conducted to evaluate soil solarization, Midas™ (iodomethane:chloropicrin 50:50, Arysta LifeScience Corp., Cary, NC) and different rates and formulations of methyl bromide under standard and metalized films for the production of snapdragon (Antirrhinum majus) in Martin County, Flor...

  5. Development of variable-rate precision spraying systems for tree crop production

    Excessive pesticides are often applied to target and non-target areas in orchards and nurseries, resulting in greater production costs, worker exposure to unnecessary pesticide risks, and adverse contamination of the environment. To improve spray application efficiency, two types of variable-rate pr...

  6. Second international comparison on measuring techniques of tritium production rate for fusion neutronics experiments (ICMT-2)

    An second international comparison on measuring techniques of tritium production rates for fusion neutronics experiments (ICMT-2) has been performed. The purpose is to evaluate the measurement accuracy of tritium production rates in the current measurement techniques. Two 14 MeV neutron source facilities, FNS at JAERI-Japan and LOTUS at EPFL-Switzerland, were used for this purpose. Nine groups out of seven countries participated in this program. A fusion simulated blanket assembly of simple-geometry was served as the test bed at each facility, in which Li-containing samples from the participants were irradiated in an uniform neutron field. The tritium production rates were determined by the participants using their own ways by using the liquid scintillation counting method. Tritiated water sample with unknown but the same concentration was also distributed and its concentration was measured to make a common reference. The standard deviation of measured tritium production rates among participants was about 10 % for both FNS and LOTUS irradiation levels: 4x10-13 T-atoms/Li-atom and 1.6x10-12 T-atoms/Li-atom at a sample, respectively. This standard deviation exceeds the expected deviation of 5 % in this program. It is presumed that the deviation of 10 % is caused mainly by the systematic and unknown errors in a process of tritium extraction from the irradiated samples depending on each organization. (author)

  7. The autonomic and rate pressure product responses of Tai Chi practitioners

    Michael A Figueroa

    2012-01-01

    Full Text Available Background: Spectral analysis of autonomic nervous system activity can provide insight into cardiovascular function. Rate pressure product is the parameter often targeted pharmacologically to decrease the incidence of myocardial events. Aim: The purpose of this study was to investigate whether or not Tai Chi Chuan practitioners would demonstrate autonomic responses that would be more cardioprotective when compared to non-trained controls. Materials and Methods: This was a cross-sectional study that measured the autonomic responses and rate pressure product of 2 groups of subjects; a Tai Chi Chuan trained (n = 13 and non-trained sedentary controls (n = 13 at rest and during 2 stressor phases that simulated functional activities of daily living. Results: The Tai Chi group maintained a greater parasympathetic outflow at rest and during the isometric grip stressor phase (P<0.05. Sympathetic outflow, systolic blood pressure and rate pressure product were significantly lower in the Tai Chi group at rest, during the isometric grip and standing stressor phases (P<0.05. Conclusion: Although a cause-and-effect relationship cannot be concluded in this study, the Tai Chi group was able to demonstrate efficiency of the myocardium with suppressed rate pressure product values and autonomic responses that favored parasympathetic outflow. This type of training may complement non-pharmacological anti-hypertensive therapy.

  8. Construction of the rating of competitiveness of facilities of light aircraft of Ukrainian and Russian production

    А.I. Yakovlev

    2010-12-01

    Full Text Available Methodical approaches to determination of level of competitiveness of the small flying machines made in the various countries are considered. The valuation method of coefficients of weightiness of indicators of competitiveness is developed. The market rating of small airplanes of Ukrainian and Russian production is built.

  9. Electrostatic levitation, control and transport in high rate, low cost production of inertial confinement fusion targets

    Inertial confinement fusion requires production of power plant grade targets at high rates and process yield. A review of present project specifications and techniques to produce targets is discussed with special emphasis on automating the processes and combining them with an electrostatic transport and suspension system through the power plant target factory

  10. Ion production rate in a boreal forest based on ion, particle and radiation measurements

    L. Laakso

    2004-01-01

    Full Text Available In this study the ion production rates in a boreal forest were studied based on two different methods: 1 cluster ion and particle concentration measurements, 2 external radiation and radon concentration measurements. Both methods produced reasonable estimates for ion production rates. The average ion production rate calculated from aerosol particle size distribution and air ion mobility distribution measurements was 2.6 ion pairs cm-3s-1, and based on external radiation and radon measurements, 4.5 ion pairs cm-3s-1. The first method based on ion and particle measurements gave lower values for the ion production rates especially during the day. A possible reason for this is that particle measurements started only from 3nm, so the sink of small ions during the nucleation events was underestimated. It may also be possible that the hygroscopic growth factors of aerosol particles were underestimated. Another reason for the discrepancy is the nucleation mechanism itself. If the ions are somehow present in the nucleation process, there could have been an additional ion sink during the nucleation days.

  11. Ion production rate in a boreal forest based on ion, particle and radiation measurements

    Laakso, L.; Petäjä, T.; Lehtinen, K. E. J.; Kulmala, M.; Paatero, J.; Hõrrak, U.; Tammet, H.; Joutsensaari, J.

    2004-09-01

    In this study the ion production rates in a boreal forest were studied based on two different methods: 1) cluster ion and particle concentration measurements, 2) external radiation and radon concentration measurements. Both methods produced reasonable estimates for ion production rates. The average ion production rate calculated from aerosol particle size distribution and air ion mobility distribution measurements was 2.6 ion pairs cm-3s-1, and based on external radiation and radon measurements, 4.5 ion pairs cm-3s-1. The first method based on ion and particle measurements gave lower values for the ion production rates especially during the day. A possible reason for this is that particle measurements started only from 3nm, so the sink of small ions during the nucleation events was underestimated. It may also be possible that the hygroscopic growth factors of aerosol particles were underestimated. Another reason for the discrepancy is the nucleation mechanism itself. If the ions are somehow present in the nucleation process, there could have been an additional ion sink during the nucleation days.

  12. Ion production rate in a boreal forest based on ion, particle and radiation measurements

    L. Laakso

    2004-07-01

    Full Text Available In this study the ion production rates in a boreal forest are studied based on two different methods: 1 cluster ion and particle concentration measurements, 2 external radiation and radon concentration measurements. Both methods produce reasonable estimates for ion production rates. The average ion production rate calculated from aerosol particle size distribution and air ion mobility distribution measurements was 2.6 cm−3s−1 and based on external radiation and radon measurements 4.5 cm−3s−1. The first method based on ion and particle measurements gave lower values for the ion production rates especially during the day. A possible reason for this is that particle measurements started only from 3 nm, so the sink of small ions during the nucleation events was underestimated. Another reason is that the possible fogs, which caused an extra sink of small ions are not taken into account in the calculations. It may also be possible that the hygroscopic growth factors of aerosol particles were underestimated. A fourth possible reason for the discrepancy is the nucleation mechanism itself. If the ions were somehow present in the nucleation process, there could have been an additional ion sink during the nucleation days. On the other hand, not all the radiation energy is converted to ions and the possible effect of alpha recoil is also omitted.

  13. Investigation of OxProduction Rates in the Mexico City Metropolitan Area during MILAGRO

    Dusanter, S.; Molina, L. T.; Stevens, P. S.

    2009-12-01

    Understanding the oxidative capacity of the atmosphere and the formation of secondary pollutants are important issues in atmospheric chemistry. For instance, the photochemical production of tropospheric ozone (O3) is of particular interest due to its detrimental effects on both human health and agricultural ecosystems. A detailed characterization of tropospheric O3 production rates will help in the development of effective control strategies. The 2006 Mexico City Metropolitan Area field campaign (MCMA-2006) was one of four components of MILAGRO (Megacity Initiative: Local And Global Research Observations) intended to collect information on the impact of megacity emissions on local, regional and global scales. In this presentation, rates of production of Ox (Ox = O3 + NO2) species during MCMA-2006 at the supersite T0 (Instituto Mexicano del Petroleo) will be presented using different approaches based on measured and modeled concentrations of ROx (OH + HO2 + RO2) radicals. In addition, we will examine both the reactivity of OH and the contribution of specific peroxy radicals to the oxidation rate of NO to estimate the contribution of groups of VOCs (alkanes, alkenes, aromatics, oxygenated and biogenic VOCs) to the total production rate of Ox species.

  14. Implications of two Holocene time-dependent geomagnetic models for cosmogenic nuclide production rate scaling

    Lifton, Nathaniel

    2016-01-01

    The geomagnetic field is a major influence on in situ cosmogenic nuclide production rates at a given location (in addition to atmospheric pressure and, to a lesser extent, solar modulation effects). A better understanding of how past fluctuations in these influences affected production rates should allow more accurate application of cosmogenic nuclides. As such, this work explores the cosmogenic nuclide production rate scaling implications of two recent time-dependent spherical harmonic geomagnetic models spanning the Holocene. Korte and Constable (2011, Phys. Earth Planet. Inter.188, 247-259) and Korte et al. (2011, Earth Planet. Sci. Lett. 312, 497-505) recently updated earlier spherical harmonic paleomagnetic models with new paleomagnetic data from sediment cores in addition to new archeomagnetic and volcanic data. These updated models offer improved resolution and accuracy over the previous versions, in part due to increased temporal and spatial data coverage. In addition, Pavón-Carrasco et al. (2014, Earth Planet. Sci. Lett. 388, 98-109) developed another time-dependent spherical harmonic model of the Holocene geomagnetic field, based solely on archeomagnetic and volcanic paleomagnetic data from the same underlying paleomagnetic database as the Korte et al. models, but extending to 14 ka. With the new models as input, trajectory-traced estimates of effective vertical cutoff rigidity (RC - the standard method for ordering cosmic ray data) yield significantly different time-integrated scaling predictions when compared to each other and to results using the earlier models. In addition, predictions of each new model using RC are tested empirically using recently published production rate calibration data for both 10Be and 3He, and compared to predictions using corresponding time-varying geocentric dipolar RC formulations and a static geocentric axial dipole (GAD) model. Results for the few calibration sites from geomagnetically sensitive regions suggest that the

  15. Supply chain coordination for a deteriorating product under stock-dependent consumption rate and unreliable production process

    B. C. Giri

    2011-04-01

    Full Text Available This article develops a supply chain coordination model with a single-vendor and a single-buyer. The vendor manufactures the product in lots and delivers to the buyer in equal shipments. However, the vendor’s production process is not perfectly reliable. During a production run, the process may shift from an in-control state to an out-of-control state at any random time and produces some defective items. The buyer whose demand is assumed to be linear function of the on-hand inventory performs a screening process immediately after each replenishment. Moreover, the buyer’s inventory is deteriorated at a constant rate over time. The vendor-buyer coordination policy is determined by minimizing the average cost of the supply chain. It is observed from the numerical study that channel coordination earns significant cost savings over the non-coordinated policy.

  16. Production rates of strange vector mesons at the Z{sup 0} resonance

    Dima, M.O.

    1997-05-01

    This dissertation presents a study of strange vector meson production, {open_quotes}leading particle{close_quotes} effect and a first direct measurement of the strangeness suppression parameter in hadronic decays of the neutral electroweak boson, Z{sup 0}. The measurements were performed in e{sup +}e{sup -} collisions at the Stanford Linear Accelerator Center (SLAC) with the SLC Large Detector (SLD) experiment. A new generation particle ID system, the SLD Cerenkov Ring Imaging Detector (CRID) is used to discriminate kaons from pions, enabling the reconstruction of the vector mesons over a wide momentum range. The inclusive production rates of {phi} and K*{sup 0} and the differential rates versus momentum were measured and are compared with those of other experiments and theoretical predictions. The high longitudinal polarisation of the SLC electron beam is used in conjunction with the electroweak quark production asymmetries to separate quark jets from antiquark jets. K*{sup 0} production is studied separately in these samples, and the results show evidence for the {open_quotes}leading particle{close_quotes} effect. The difference between K*{sup 0} production rates at high momentum in quark and antiquark jets yields a first direct measurement of strangeness suppression in jet fragmentation.

  17. Production rates of strange vector mesons at the Z0 resonance

    This dissertation presents a study of strange vector meson production, open-quotes leading particleclose quotes effect and a first direct measurement of the strangeness suppression parameter in hadronic decays of the neutral electroweak boson, Z0. The measurements were performed in e+e- collisions at the Stanford Linear Accelerator Center (SLAC) with the SLC Large Detector (SLD) experiment. A new generation particle ID system, the SLD Cerenkov Ring Imaging Detector (CRID) is used to discriminate kaons from pions, enabling the reconstruction of the vector mesons over a wide momentum range. The inclusive production rates of φ and K*0 and the differential rates versus momentum were measured and are compared with those of other experiments and theoretical predictions. The high longitudinal polarisation of the SLC electron beam is used in conjunction with the electroweak quark production asymmetries to separate quark jets from antiquark jets. K*0 production is studied separately in these samples, and the results show evidence for the open-quotes leading particleclose quotes effect. The difference between K*0 production rates at high momentum in quark and antiquark jets yields a first direct measurement of strangeness suppression in jet fragmentation

  18. Production rate of pollen grains of castanea crenata in a quercus serrata secondary forest

    Kiyonaga, Jota

    1995-01-01

    The production rate of pollen grains of Castanea crenata in a secondary Quercus serrata forest was determined in 1990-1993, based on the number of pollen grains per male catkin and annual fall rate of male catkins. The latter parameter was measured using six litter traps. The annual production rate of pollen grains in 1990-1992 was 9.7×10^<11>-3.7×10^<12>no.ha^<-1>yr^<-1>. The mean value for the four years was 2.0×10^<12>no.ha^<-1>yr^<-1>. Resumo Produktaĵo de poleneroj (no.ha^<-1>yr^<-1>) de...

  19. Production rate of quercus glauca pollen grains in a quercus glauca secondary forest

    Kiyonaga, Jota

    2002-01-01

    The production rate of pollen grains of Quercus glauca, in a secondary Q. glauca forest was determined over a three-year period, based on the number of pollen grains per male catkin and the fall rate of the male catkins. The latter parameter was measured using six litter traps. The annual production rate of pollen grains from 1996-1998 was 2.0×10^<11> 7.8×10^<11> no. ha^<-1>yr^1. The mean value for the three years is 4.4×10^lt;11> no.ha^<-1>yr^1. This value. which is lower than the results fr...

  20. Effects of alternating magnetic field on the corrosion rate and corrosion products of copper

    GUO Bin; ZHANG Peng; JIN Yongping; CHENG Shukang

    2008-01-01

    The effects of alternating magnetic field on the corrosion morphologies, corrosion rate, and corrosion products of copper in 3.5% NaCl solution, sea water, and magnetized sea water were investigated using electrochemical test, scanning electron microscopy/energy dispersive analysis system of X-ray (SEM/EDAX), and X-ray diffraction (XRD). The results show that the corrosion rate of copper in magnetized sea water is minimal. Moreover, the surface of the specimen in magnetized sea water is uniform and compact as compared with those in 3.5% NaCl solution and sea water. The corrosion products of copper in magnetized sea water are mainly Cu2O and CuCl2. However, the corrosion products in sea water are CuCl, Cu2Cl(OH)3, and FeCl3·6H2O. The electrochemical corrosion mechanisms of copper in the three media were also discussed.

  1. Cosmogenic nuclide production rate systematics in terrestrial materials: Present knowledge, needs and future actions for improvement

    The growing applications of cosmogenic nuclides produced in the Earth's atmosphere, and in situ in a variety of terrestrial materials, as tracers in a wide ranging Earth science problems, has put a greater demand on accurate determination of the nuclide production rates in a variety of targets exposed in different settings on the Earth in the troposphere. The present state of our knowledge of cosmogenic production rates is reviewed briefly, in conjunction with the phenomenological and theoretical framework for: (i) the cosmic ray flux incident in the near Earth environment, (ii) the nucleonic cascade set off in the Earth's atmosphere by the primary cosmic radiation, and (iii) the rate for production of nuclides in terrestrial materials, in widely different settings. These considerations set the stage for the diverse questions, which must be taken into account for determining the source functions of isotopic changes in terrestrial materials. We discuss the different approaches which have been adopted earlier to obtain the source strengths of nuclear interacting particles of the cosmic radiation, and direct measurements of nuclide production rates made by exposing targets to cosmic radiation at sea level and at mountain altitudes. We show that rapid progress in determining nuclide source functions with sufficient information on temporal variability is indeed expected in the near future as a result of: (i) dramatic improvements in the past 2-3 decades in our understanding of the character of propagation of cosmic radiation within the heliosphere, (ii) experiments now being conducted by a few groups to determine the source strengths of cosmic ray slow neutrons, and nuclide production rates in cosmic ray exposed targets, and finally (iii) the emergence of better nuclear codes which deal with the development of nucleonic cascades in the Earth's atmosphere

  2. Statistical Optimization of Xanthan Gum Production and Influence of Airflow Rates in Lab-scale Fermentor

    S. Moshaf

    2014-09-01

    Full Text Available The present study was undertaken to investigate and optimize the possibility of xanthan gum production by Xanthomonas campestris PTCC1473 in 500ml shake flasks on the second grade date palm. Using an experimental response surface methodology (RSM coupled with a central composite design (CCD, three major independent variables (nitrogen source, phosphor source and agitation rate were evaluated for their individual and interactive effects on biomass and xanthan gum production in submerged fermentation. The optimum conditions selected for gum production were 3.15 g.l-1 for nitrogen source, 5.03 g.l-1 for phosphor source, and 394.8 rpm for agitation rate. Reconfirmation test was conducted, and the experimental value obtained for xanthan production under optimum conditions was about 6.72±0.26 g.l-1, which was close to 6.51 g.l-1 as predicted by the model. A higher yield of biomass production was obtained at 13.74 g.l-1 for nitrogen source, 4.66 g.l-1 for phosphor source, and 387.42 rpm for agitation rate. In the next stage, scale-up from the shake flasks to the 1-L batch fermentors was carried. By using the optimum conditions for xanthan gum, the biomass and xanthan gum concentrations after 72h in three levels of air flow rate (0.5, 1 and 1.5 vvm were obtained as 3.98, 5.31 and 6.04 g.l-1,and 11.32, 15.16 and 16.84 g.l-1, respectively. Overall, the second grade date palm seemed to exhibit promising properties that can open new pathways for the production of efficient and cost-effective xanthan gum.

  3. In vitro O 2 fluxes compared with 14C production and other rate terms during the JGOFS Equatorial Pacific experiment

    Bender, Michael; Orchardo, Joe; Dickson, Mary-Lynn; Barber, Richard; Lindley, Steven

    1999-04-01

    We report rates of gross and net O 2 production measured in vitro during JGOFS cruises in the equatorial Pacific in spring and fall, 1992. We scale O 2 productivities to net and gross C production. We then compare the calculated rates with 14C production and with new/export production measured by various techniques. 14C productivities in samples incubated for 24 h are about 45% of gross carbon production rates calculated from gross O 2 production. The difference is compatible with expected rates of the Mehler reaction, photorespiration, excretion, and community mitochondrial respiration. 14C production rates are similar to net carbon production rates in the upper half of the euphotic zone. At lower irradiances, where net C production can be zero or less, 14C productivities lie between net community production and gross primary production. Net carbon production rates in vitro are a factor of =4-20 times greater than estimates from drifting sediment trap and tracer transport studies. This difference probably reflects anomalous accumulation of POC in bottles because of the exclusion of grazers.

  4. High production rate of crystallization process in TFA-MOD method for YBCO coated conductors

    To realize a higher production rate is one of the important issues in the development of the long-tape processing for the YBCO coated conductors by the TFA-MOD process using the reel-to-reel system. Not only scale-up of the furnace and decrease of YBCO thickness with the higher J c value, but higher YBCO growth rates could be effective to achieve a higher traveling rate in this system. It was confirmed that optimization of the process parameters such as high water vapor partial pressure, high diffusion constants due to a low applied total pressure, and a high gas flow rate affect the YBCO growth rate. Consequently, these higher growth rate conditions were simultaneously applied to the reel-to-reel system. As a result, the traveling rate of 1.2 m/h was achieved for fabricating YBCO films in the reel-to-reel system, which is about five times as fast as the previous traveling rate with maintaining high I c value of higher than 200 A/cm-width by controlling above conditions

  5. Absolute production rate measurements of nitric oxide by an atmospheric pressure plasma jet (APPJ)

    Pipa, A V; Bindemann, T; Foest, R; Kindel, E; Roepcke, J; Weltmann, K-D [Leibniz-Institut fuer Plasmaforschung and Technologie e.V. (INP), Felix-Hausdorff Strasse 2, D-17489 Greifswald (Germany)], E-mail: foest@inp-greifswald.de

    2008-10-07

    Tunable diode laser absorption spectroscopy (TDLAS) has been applied to measure the absolute production rate of NO molecules in the gas phase of an atmospheric pressure plasma jet (APPJ) operating at rf (13.56 MHz) in argon with small (up to 1%) admixtures of air. The resulting NO production rates were found to be in the range (0.1-80) x 10{sup -3} sccm or (0.05-35) x 10{sup 18} molecules s{sup -1} depending on the experimental conditions. Maximum rates were obtained at 0.2% air. For TDLAS measurements the APPJ was arranged inside an astigmatic multi-pass cell of Herriott type with 100 m absorption length. The insertion into a closed volume differs slightly from the normal, open operation with the jet propagating freely into air. Therefore, the measuring results are compared with optical emission of the open jet to verify equivalent experimental conditions. The dependence of the optical emission of NO (237 nm) on power and gas mixture has been measured. The similar shape of the dependence of absorption and emission signals gives evidence that the comparability of experimental conditions is sufficiently satisfied. It is concluded that the NO production rate of the APPJ in ambient air can be characterized using TDLAS and provides reliable results in spite of differing experimental conditions due to the set-up.

  6. Integrated Strategic Planning of Global Production Networks and Financial Hedging under Uncertain Demands and Exchange Rates

    Achim Koberstein

    2013-11-01

    Full Text Available In this paper, we present a multi-stage stochastic programming model that integrates financial hedging decisions into the planning of strategic production networks under uncertain exchange rates and product demands. This model considers the expenses of production plants and the revenues of markets in different currency areas. Financial portfolio planning decisions for two types of financial instruments, forward contracts and options, are represented explicitly by multi-period decision variables and a multi-stage scenario tree. Using an illustrative example, we analyze the impact of exchange-rate and demand volatility, the level of investment expenses and interest rate spreads on capacity location and dimensioning decisions. In particular, we show that, in the illustrative example, the exchange-rate uncertainty cannot be completely eliminated by financial hedging in the presence of demand uncertainty. In this situation, we find that the integrated model can result in better strategic planning decisions for a risk-averse decision maker compared to traditional modeling approaches.

  7. Influence of Production System, Sex and Litter Size on Growth Rates in Turcana Lambs

    Dinu Gavojdian

    2013-10-01

    Full Text Available Lamb meat production has become the main source of income in the Romanian sheep farming industry, representing over 66% of the total returns. Turcana breed represents over 70% of the national flock, and 92% of the sheep bred in western Romania. However, meat production potential and growth rates of the breed are low, and thus strategies to improve performance of the Turcana lambs need to be identified. Aim of the current research was to evaluate the effects that sex and litter size have on the growth rates of lambs from Turcana breed under extensive and semi-intensive production systems. Weaning weight was significantly (p≤0.001 influenced by the production system, with lambs reared extensively registering a average body weights of 18.23±0.094 kg at the age of 90 days, while the semi-intensively reared lambs registered an average weight of 20.19±0.082 kg. It was concluded that all three factors taken into study significantly influence growth rates in Turcana lambs and that weight of the lamb(s at the age of 28 days should be included as a selection trait within the Turcana breed genetic improvement plan.

  8. Exposure testing of fasteners in preservative treated wood: Gravimetric corrosion rates and corrosion product analyses

    Research highlights: → The composition of the corrosion products was similar for the nail head and shank. → Reduced copper was not detected on any of the fasteners. → Measured corrosion rates were between 1 and 35 μm year-1. - Abstract: Research was conducted to determine the corrosion rates of metals in preservative treated wood and also understand the mechanism of metal corrosion in treated wood. Steel and hot-dip galvanized steel fasteners were embedded in wood treated with one of six preservative treatments and exposed to 27 oC at 100% relative humidity for 1 year. The corrosion rate was determined gravimetrically and the corrosion products were analyzed with scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. Although the accepted mechanism of corrosion in treated wood involves the reduction of cupric ions from the wood preservative, no reduced copper was found on the corrosion surfaces. The galvanized corrosion products contained sulfates, whereas the steel corrosion products consisted of iron oxides and hydroxides. The possible implications and limitations of this research on fasteners used in building applications are discussed.

  9. Evaluating the effect of exchange rate and labor productivity on import penetration of Brazilian manufacturing sectors

    João Paulo Martin Faleiros

    2016-01-01

    Full Text Available In recent years, several economists have argued that the sharp loss of competitiveness of the Brazilian industry was caused by a strong exchange rate appreciation. However, other economists have attributed this loss of competitiveness to the dismal growth of labor productivity in the Brazilian industrial sector. The present paper proposes to estimate the differential impacts of variations in exchange rate and labor productivity on the Brazilian market share of imports measured by the coefficient of import penetration of total demand for manufacturing goods. We start by developing a simple theoretical model to investigate under what conditions the impacts of an exchange rate depreciation and an increase in labor productivity would differ. We test the theoretical implications of the model by means of a GMM panel data analysis focusing on 17 manufacturing sectors in the period between 1996 and 2011. Our results suggest that both variables matter to explain the coefficient of import penetration. Nevertheless, labor productivity has the strongest negative impact on the market share of imported goods, even after controlling for sector fixed-effects.

  10. Optimising stocking rate and grazing management to enhance environmental and production outcomes for native temperate grasslands

    Badgery, Warwick; Zhang, Yingjun; Huang, Ding; Broadfoot, Kim; Kemp, David; Mitchell, David

    2015-04-01

    Stocking rate and grazing management can be altered to enhance the sustainable production of grasslands but the relative influence of each has not often been determined for native temperate grasslands. Grazing management can range from seasonal rests through to intensive rotational grazing involving >30 paddocks. In large scale grazing, it can be difficult to segregate the influence of grazing pressure from the timing of utilisation. Moreover, relative grazing pressure can change between years as seasonal conditions influence grassland production compared to the relative constant requirements of animals. This paper reports on two studies in temperate native grasslands of northern China and south eastern Australia that examined stocking rate and regionally relevant grazing management strategies. In China, the grazing experiment involved combinations of a rest, moderate or heavy grazing pressure of sheep in spring, then moderate or heavy grazing in summer and autumn. Moderate grazing pressure at 50% of the current district average, resulted in the better balance between maintaining productive and diverse grasslands, a profitable livestock system, and mitigation of greenhouse gases through increased soil carbon, methane uptake by the soil, and efficient methane emissions per unit of weight gain. Spring rests best maintained a desirable grassland composition, but had few other benefits and reduced livestock productivity due to lower feed quality from grazing later in the season. In Australia, the grazing experiment compared continuous grazing to flexible 4- and 20-paddock rotational grazing systems with sheep. Stocking rates were adjusted between systems biannually based on the average herbage mass of the grassland. No treatment degraded the perennial pasture composition, but ground cover was maintained at higher levels in the 20-paddock system even though this treatment had a higher stocking rate. Overall there was little difference in livestock production (e.g. kg

  11. Rerouting Cellular Electron Flux To Increase the Rate of Biological Methane Production.

    Catlett, Jennie L; Ortiz, Alicia M; Buan, Nicole R

    2015-10-01

    Methanogens are anaerobic archaea that grow by producing methane, a gas that is both an efficient renewable fuel and a potent greenhouse gas. We observed that overexpression of the cytoplasmic heterodisulfide reductase enzyme HdrABC increased the rate of methane production from methanol by 30% without affecting the growth rate relative to the parent strain. Hdr enzymes are essential in all known methane-producing archaea. They function as the terminal oxidases in the methanogen electron transport system by reducing the coenzyme M (2-mercaptoethane sulfonate) and coenzyme B (7-mercaptoheptanoylthreonine sulfonate) heterodisulfide, CoM-S-S-CoB, to regenerate the thiol-coenzymes for reuse. In Methanosarcina acetivorans, HdrABC expression caused an increased rate of methanogenesis and a decrease in metabolic efficiency on methylotrophic substrates. When acetate was the sole carbon and energy source, neither deletion nor overexpression of HdrABC had an effect on growth or methane production rates. These results suggest that in cells grown on methylated substrates, the cell compensates for energy losses due to expression of HdrABC with an increased rate of substrate turnover and that HdrABC lacks the appropriate electron donor in acetate-grown cells. PMID:26162885

  12. Voice recognition versus transcriptionist: error rated and productivity in MRI reporting

    Full text: Purpose: Despite the frequent introduction of voice recognition (VR) into radiology departments, little evidence still exists about its impact on workflow, error rates and costs. We designed a study to compare typographical errors, turnaround times (TAT) from reported to verified and productivity for VR-generated reports versus transcriptionist-generated reports in MRI. Methods: Fifty MRI reports generated by VR and 50 finalised MRI reports generated by the transcriptionist, of two radiologists, were sampled retrospectively. Two hundred reports were scrutinised for typographical errors and the average TAT from dictated to final approval. To assess productivity, the average MRI reports per hour for one of the radiologists was calculated using data from extra weekend reporting sessions. Results: Forty-two % and 30% of the finalised VR reports for each of the radiologists investigated contained errors. Only 6% and 8% of the transcriptionist-generated reports contained errors. The average TAT for VR was 0 h, and for the transcriptionist reports TAT was 89 and 38.9 h. Productivity was calculated at 8.6 MRI reports per hour using VR and 13.3 MRI reports using the transcriptionist, representing a 55% increase in productivity. Conclusion: Our results demonstrate that VR is not an effective method of generating reports for MRI. Ideally, we would have the report error rate and productivity of a transcriptionist and the TAT of VR.

  13. US PRICE INDICES AND THE EXCHANGE RATE: ARE RECREATIONAL PRODUCTS DIFFERENT?

    Cellini, Roberto; Alessandro PAOLINO

    2009-01-01

    The paper analyses the cointegration relationships and the causal links between the exchange rate of the US Dollar, on the one side, and different price indices of US products on the other side. Data are of monthly frequency and cover a period of two or three decades. We show that the exchange rate cointegrate with the Consumer Price Index and with the prices indices of several agricultural, manufactured and service goods; moreover a one-direction causal link is present, running from price to...

  14. The determination and analysis of site-specific rates of mitochondrial reactive oxygen species production

    Quinlan, Casey L; Perevoschikova, Irina V; Goncalves, Renata L S;

    2013-01-01

    production in the electron transport chain and matrix compartment. In this chapter, we describe the nature of the mitochondrial ROS-producing machinery and the relative capacities of each site. We provide detailed methods for the measurement of H2O2 release and the conditions under which maximal rates from......Mitochondrial reactive oxygen species (ROS) are widely implicated in physiological and pathological pathways. We propose that it is critical to understand the specific sites of mitochondrial ROS production and their mechanisms of action. Mitochondria possess at least eight distinct sites of ROS...

  15. Scalable Method for Extracting Soiling Rates from PV Production Data: Preprint

    Deceglie, Michael G.; Muller, Matthew; Kurtz, Sarah; Defreitas, Zoe

    2016-06-21

    We present a method for analyzing time series production data from photovoltaic systems to extract the rate at which energy yield is affected by the accumulation of dust, dirt, and other forms of soiling. We describe an approach that is based on prevailing methods which consider the change in energy production during dry periods. The method described here builds upon these methods by considering a statistical sample of soiling intervals from each site under consideration. The method enables straightforward application to a large number of sites with minimal parameterization of data-filtering requirements. Furthermore, it enables statistical confidence intervals and comparisons between sites.

  16. Rolling With Simplified Stream Function Velocity and Strain Rate Vector Inner Product

    2012-01-01

    The dual-stream function velocity field is reduced in order to analyze two-dimensional plate broadside roll- ing in roughing. The strain rate vector inner product and integral mean value theorem, as well as coqine vector inner product are used respectively in plastic deformation power, friction losses and shear power. A theoretical solution of roll torque and separating force for the rolling is obtained and the calculated results by the solution are compared with those measured in broadside rolling on-line. It shows that both the force and torque calculated are higher than those of measured, but the maximum relative error between them is no more than 11%.

  17. Detection rates of the MODIS active fire product in the United States

    Hawbaker, T.J.; Radeloff, V.C.; Syphard, A.D.; Zhu, Z.; Stewart, S.I.

    2008-01-01

    MODIS active fire data offer new information about global fire patterns. However, uncertainties in detection rates can render satellite-derived fire statistics difficult to interpret. We evaluated the MODIS 1??km daily active fire product to quantify detection rates for both Terra and Aqua MODIS sensors, examined how cloud cover and fire size affected detection rates, and estimated how detection rates varied across the United States. MODIS active fire detections were compared to 361 reference fires (??? 18??ha) that had been delineated using pre- and post-fire Landsat imagery. Reference fires were considered detected if at least one MODIS active fire pixel occurred within 1??km of the edge of the fire. When active fire data from both Aqua and Terra were combined, 82% of all reference fires were found, but detection rates were less for Aqua and Terra individually (73% and 66% respectively). Fires not detected generally had more cloudy days, but not when the Aqua data were considered exclusively. MODIS detection rates decreased with fire size, and the size at which 50% of all fires were detected was 105??ha when combining Aqua and Terra (195??ha for Aqua and 334??ha for Terra alone). Across the United States, detection rates were greatest in the West, lower in the Great Plains, and lowest in the East. The MODIS active fire product captures large fires in the U.S. well, but may under-represent fires in areas with frequent cloud cover or rapidly burning, small, and low-intensity fires. We recommend that users of the MODIS active fire data perform individual validations to ensure that all relevant fires are included. ?? 2008 Elsevier Inc. All rights reserved.

  18. An EPLS model for a variable production rate with stock-price sensitive demand and deterioration

    Roy T.

    2012-01-01

    Full Text Available It is observed that large piles of consumer goods displayed in supermarkets lead consumers to buy more, which generates more profit to sellers. But a large number of on-hand display of stock leaves a negative impression on the buyer. Also, the amount of shelf or display space is limited. Due to this reason, we impose a restriction on the number of on-hand display of stock and also on initial and ending on-hand stock levels. We introduce an economic production lot size model, where production rate depends on stock and selling price per unit. A constant fraction deterioration rate is considered in this model. To illustrate the results of the model, four numerical examples are established. Sensitivity analysis of the changes of parameter values is also given.

  19. Production Rate of Second KK Gauge Bosons in UED Models at LHC

    Matsumoto, Shigeki; Senami, Masato; Yamanaka, Masato

    2009-01-01

    We calculate the production rates of the second Kaluza-Klein (KK) photon $\\gamma^{(2)}$ and Z boson $Z^{(2)}$ at the LHC including all significant processes in the minimal universal extra dimension (MUED) model. For discrimination of the MUED model from other TeV scale models in hadron collider experiments, $\\gamma^{(2)}$ and $Z^{(2)}$ play a crucial role. In order to discuss the discrimination and calculate their production rates, we derive effective Lagrangian containing KK number violating operators. We show that KK number violating processes are extremely important for the compactification scale larger than 800 GeV. We find that, with an integrated luminosity of 100 fb$^{-1}$, $\\gamma^{(2)}$ and $Z^{(2)}$ are produced 10$^6$ - 10$^2$ for the compactification scale between 400 GeV and 2000 GeV.

  20. Three stage supply chain model with two warehouse, imperfect production, variable demand rate and inflation

    Preety Gupta

    2013-01-01

    Full Text Available This study develops an integrated production inventory model from the perspectives of vendor, supplier and buyer. The demand rate is time dependent for the vendor and supplier and buyer assumes the stock dependent demand rate. As per the demand, supplier uses two warehouses (rented and owned for the storage of excess quantities. Shortages are allowed at the buyer’s part only and the unfulfilled demand is partially backlogged. The effect of imperfect production processes on lot sizing is also considered. This complete model is studied under the effect of inflation. The objective is to minimize the total cost for the system. A solution procedure is developed to find a near optimal solution for the model. A numerical example along with sensitivity analysis is given to illustrate the model.

  1. Computational Fluid Dynamics Modeling to Improve Natural Flow Rate and Sweet Pepper Productivity in Greenhouse

    Limtrakarn, W.; Boonmongkol, P.; Chompupoung, A.; K. Rungprateepthaworn; J. Kruenate; Dechaumphai, P.

    2012-01-01

    Natural flow rate and sweet peppers productivity in tropical greenhouse are improved by CFD simulation is the main objective of this research work. Most of the greenhouse types today are in the arch shape. To develop an improved greenhouse structure for the region, the arch type was built and used as the control model. Mae Sar Mai agriculture research station under the royal project foundation was selected as the field test site. Temperature sensors with data logger were installed to monitor ...

  2. Metabolic rate and environmental productivity: Well-provisioned animals evolved to run and idle fast

    Mueller, Pamela; Diamond, Jared

    2001-01-01

    Even among vertebrate species of the same body mass and higher-level taxonomic group, metabolic rates exhibit substantial differences, for which diverse explanatory factors—such as dietary energy content, latitude, altitude, temperature, and rainfall—have been postulated. A unifying underlying factor could be food availability, in turn controlled by net primary productivity (NPP) of the animal's natural environment. We tested this possibility by studying five North American species of Peromys...

  3. The Correlation between Long-Term Productivity and Short-Term Performance Ratings of Harvester Operators

    2011-01-01

    Human operators are key determinants of the performance of most production systems, so individual performance is of intrinsic interest when evaluating current and proposed systems for forest operations. Such evaluations can be useful for diverse purposes, for instance, planning, incentive-setting, control and costing. Hence, various evaluation methods have been developed, all with pros and cons. Here, we compare subjective, short-term ratings of the work-related behavior of 12 harvester opera...

  4. AGING AND GENDER EFFECTS ON RATE-PRESSURE PRODUCT: AN INDEX OF MYOCARDIAL OXYGEN CONSUMPTION

    Shrilaxmi Chandrashekar Bagali; Jyoti Paramanand Khodnapur; Lata Mallappa Mullur; Sheikh, Gouhar Banu U; Manjunatha Ramakrishna Aithala

    2012-01-01

    Objectives: There are aging associated alterations in cardiac structure, metabolism, function. Evidence suggests alterations in myocardial metabolism contribute to the development, progression of heart failure. Hence it is essential to be aware of the impact of healthy aging on myocardial oxygen consumption. Rate-Pressure Product (RPP) is simple, non-invasive, easily measurable index of MVO2. Seeking the effect of aging, we measured RPP, in apparently healthy men and women of different age gr...

  5. Biogas production from algae biomass grown in high rate ponds for wastewater treatment

    Passos, Fabiana Lopes del Rei; Cordon Casero, Sabina; Solé, Maria; Ferrer Martí, Ivet

    2011-01-01

    High rate ponds are wastewater treatment systems that combine heterotrophic bacteria and microalgae communities in a symbiosis relation, which triggers a series of reactions that eliminates pollutants from the water. Moreover, during the last decade, there has been a growing interest in investigating the energy potential of biofuels obtained from microalgae cultures. The high lipid content of microalgae makes them an alternative to terrestrial energy crops for biodiesel production. A major...

  6. Measurement of HOx· production rate due to radon decay in air

    Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce (·OH and HO2 ·) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HOx· production rate in indoor air caused by radon decay. Average HOx· production rate was found to be (4.31±0.07) x 105 HOx· per Rn decay per second (Bq) 3.4 to 55.0% at 22C. This work provided G(HOx·)-value, 7.86±0.13 No./100 eV in air by directly measuring [HOx·] formed from the radiolysis procedure. This G value implies that HOx· produced by radon decay in air might be formed by multiple processes and may be result of positive ion-molecule reactions, primary radiolysis, and radical reactions. There is no obvious relation between HOx· production rate and relative humidity. A laser-induced fluorescence (LIF) system has been used for ·OH production rate measurement; it consists of an excimer laser, a dye laser, a frequency doubler, a gaseous fluorescence chamber, and other optical and electronic parts. This system needs to be improved to eliminate the interferences of light scattering and artificial ·OH produced from the photolysis of O3/H2O

  7. On exchange, monetary credit transactions, barter, time preference, interest rates, and productivity

    Barnett II, William; BLOCK, Walter

    2006-01-01

    We attempt in this paper to tie together several basic insights of praxeology, and several that are not at all that basic. These include the following: that gains from exchange are subjective; that this applies to profits and interest; that credit transactions can occur under barter; that interest arises from time preference even under a pure time preference theory of interest; and that productivity can, under disequilibrium conditions, affect the various rates of interest.

  8. Measurement and Application of Entropy Production Rate in Human Subject Social Interaction Systems

    Xu, Bin; Wang, Zhijian

    2011-01-01

    This paper illustrates the measurement and the applications of the observable, entropy production rate (EPR), in human subject social interaction systems. To this end, we show (1) how to test the minimax randomization model with experimental economics' 2$\\times$2 games data and with the Wimbledon Tennis data; (2) how to identify the Edgeworth price cycle in experimental market data; and (3) the relationship within EPR and motion in data. As a result, in human subject social interaction system...

  9. Effect of strengthening rate on durability and long-term plasticity of semifinished metal products

    A connection between the changes of long-term properties of a metal of different melting and intermediate products of one and the same material with the features of their real tension diagram, is ascertained on the base of plastic instability model. The value of deviation by the level of long-term strength and plasiticity is characterized by a simple parameter-strengthening rate, which is determined by the Ludwick strengthening equation coefficients

  10. Effect of water flow rate and feed training on "pacamã" (Siluriforme: Pseudopimelodidae juvenile production

    R.K. Luz

    2011-08-01

    Full Text Available The effects of different water flow rates and feed training on the production of "pacamã" Lophiosilurus alexandri juveniles were evaluated. In the first experiment, nine day post-hatch larvae (n= 2,400 were stocked at a density of 5 larvae/L. Different water flow (F rates were tested: F1 = 180; F2 = 600; F3 = 1,300; and F4 = 2,600mL/min. Artemia nauplii were offered as food during the first 15 days of active feeding. In the second experiment for feed training, 720 juveniles (total length of 22.2mm were stocked at a density of 1.5 juveniles/L. A water flow rate similar to F1 was used. The use of extruded dry diet was tested, and feed training was done with and without other enhanced flavors (Artemia nauplii or Scott emulsion. The water flow rates did not influence the survival or growth of L. alexandri. Cannibalism occurred during feed training. The worst survival, specific growth rate and high mortality were found with the use of extruded dry diet, while similar values were registered with the different feed training diets used. Reduced water flow rate can be used to lower water consumption during larviculture and feed training of L. alexandri.

  11. The Kinematic and Microphysical Control of Lightning Rate, Extent and NOX Production

    Carey, Lawrence; Koshak, William; Peterson, Harold; Matthee, Retha; Bain, A. Lamont

    2014-01-01

    The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, lightning characteristics and the production of nitrogen oxides via lightning (LNOx). The focus of this study is to investigate the kinematic and microphysical control of lightning properties, particularly those that may govern LNOx production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that lightning flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOx production. To address this conceptual gap, the NASA Lightning Nitrogen Oxides Model (LNOM) is applied to North Alabama Lightning Mapping Array (NALMA) and Vaisala National Lightning Detection Network(TM) (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, lightning segment altitude distributions (SADs) and lightning NOx production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOx are available for comparison. The LNOM lightning characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell

  12. Inverse method for determining radon diffusion coefficient and free radon production rate of fragmented uranium ore

    The radon diffusion coefficient and the free radon production rate are important parameters for describing radon migration in the fragmented uranium ore. In order to determine the two parameters, the pure diffusion migration equation for radon was firstly established and its analytic solution with the two parameters to be determined was derived. Then, a self manufactured experimental column was used to simulate the pure diffusion of the radon, the improved scintillation cell method was used to measure the pore radon concentrations at different depths of the column loaded with the fragmented uranium ore, and the nonlinear least square algorithm was used to inversely determine the radon diffusion coefficient and the free radon production rate. Finally, the solution with the two inversely determined parameters was used to predict the pore radon concentrations at some depths of the column, and the predicted results were compared with the measured results. The results show that the predicted results are in good agreement with the measured results and the numerical inverse method is applicable to the determination of the radon diffusion coefficient and the free radon production rate for the fragmented uranium ore. - Highlights: • Inverse method for determining two transport parameters of radon is proposed. • A self-made experimental apparatus is used to simulate radon diffusion process. • Sampling volume and position for measuring radon concentration are optimized. • The inverse results of an experimental sample are verified

  13. High rate production of hydrogen/methane from various substrates and wastes.

    Nishio, Naomichi; Nakashimada, Yutaka

    2004-01-01

    To treat soluble and solid wastes and recover energy from them, high rate methane fermentation, especially using the UASB (upflow anaerobic sludge blanket) reactor, and hydrogen fermentation using various microorganisms and microbial consortia have been investigated intensively in Japan. In this chapter, recent works on high rate methane fermentation in Japan are reviewed, focusing on: 1) basic studies into the applicability of the UASB reactor for various substrates such as propionate, lactate, ethanol, glucose and phenol; 2) its applications to unfeasible conditions, such as lipid and protein containing wastes, low temperature and high salt-containing wastes; 3) progress made in the field of advanced UASB reactors, and; 4) research into methane fermentation from solid wastes, such as from cellulosic materials, municipal sewage sludge, and mud sediments. Following this, although hydrogen fermentation with photosynthetic microorganisms or anaerobic bacteria was researched, for this review we have focused on fermentative hydrogen production using strictly or facultative anaerobes and microbial consortia in Japan, since high rate production of hydrogen-methane via a two-stage process was judged to be more attractive for biological hydrogen production and wastewater treatments. PMID:15453185

  14. Simulation and analysis of experimental plutonium production rates in depleted uranium sphere bombarded by 14 MeV neutron

    According to the measurement of plutonium production rates resulting from 14 MeV neutrons in depleted uranium sphere, the experimental results and influencing factors were simulated and analyzed with MCNP5 code. It shows that simulant plutonium production rates from uresa and endf66c agree very well with experimental results, simulant effects on plutonium production rates by cavity, construction materials and water lays and background neutrons etc., are slight. (authors)

  15. Soil production rates on silicate parent material in high-mountains: different approaches - different results?

    Egli, Markus; Dahms, Dennis; Norton, Kevin

    2013-04-01

    High-mountain soils develop in particularly sensitive environments. Consequently, deciphering and predicting what drives the rates of soil formation in such environments is a major challenge. In terms of soil production from chemical weathering, the predominating perception for high-mountain soils and cold environments often is that the chemical weathering 'portion' of soil development is temperature-inhibited, often to the point of non-occurrence. Several concepts exist to determine long-term rates of soil formation and development. We present three different approaches: (1) quantification of soil formation from minimally eroded soils of known age using chronosequences (known surface age and soil thickness - SAST), (2) determination of soil residence times (SRT) and production rates through chemical weathering using (un)stable isotopes (e.g. 230Th / 234U activity ratios), and (3) a steady state approach using cosmogenic isotopes (e.g. 10Be). Data form different climate zones, and particularly from high-mountains (alpine environment), were compared. The SAST and steady state approach gave quite similar results for alpine environments (European Alps and the Wind River Range (Rocky Mountains USA)). Soil formation rates in mountain areas (but having a temperate climate) using the SRT approach, did not differ greatly from the SAST and Steady State approaches. Independent of the chosen approach, the results seem moderately comparable. Soil formation rates in high-mountain areas (alpine climate) ranged from very low to extremely high values and showed a clear decreasing tendency with time. Very young soils have up to 3 - 4 orders of magnitude higher rates of development than old soils (105 to 106 years). This is due to the fact that weathering is kinetically limited in regions having young surfaces and supply limited on old surfaces. Soil production rates cannot be infinitely high. Consequently, a speed limit must exist. In the literature, this limit has been set at

  16. Causes and implications of the correlation between forest productivity and tree mortality rates

    Stephenson, Nathan L.; van Mantgem, Philip J.; Bunn, Andrew G.; Bruner, Howard; Harmon, Mark E.; O'Connell, Kari B.; Urban, Dean L.; Franklin, Jerry F.

    2011-01-01

    At global and regional scales, tree mortality rates are positively correlated with forest net primary productivity (NPP). Yet causes of the correlation are unknown, in spite of potentially profound implications for our understanding of environmental controls of forest structure and dynamics and, more generally, our understanding of broad-scale environmental controls of population dynamics and ecosystem processes. Here we seek to shed light on the causes of geographic patterns in tree mortality rates, and we consider some implications of the positive correlation between mortality rates and NPP. To reach these ends, we present seven hypotheses potentially explaining the correlation, develop an approach to help distinguish among the hypotheses, and apply the approach in a case study comparing a tropical and temperate forest.

  17. Effects of heating rate on slow pyrolysis behavior, kinetic parameters and products properties of moso bamboo.

    Chen, Dengyu; Zhou, Jianbin; Zhang, Qisheng

    2014-10-01

    Effects of heating rate on slow pyrolysis behaviors, kinetic parameters, and products properties of moso bamboo were investigated in this study. Pyrolysis experiments were performed up to 700 °C at heating rates of 5, 10, 20, and 30 °C/min using thermogravimetric analysis (TGA) and a lab-scale fixed bed pyrolysis reactor. The results show that the onset and offset temperatures of the main devolatilization stage of thermogravimetry/derivative thermogravimetry (TG/DTG) curves obviously shift toward the high-temperature range, and the activation energy values increase with increasing heating rate. The heating rate has different effects on the pyrolysis products properties, including biochar (element content, proximate analysis, specific surface area, heating value), bio-oil (water content, chemical composition), and non-condensable gas. The solid yields from the fixed bed pyrolysis reactor are noticeably different from those of TGA mainly because the thermal hysteresis of the sample in the fixed bed pyrolysis reactor is more thorough. PMID:25063973

  18. Maximizing the xylitol production from sugar cane bagasse hydrolysate by controlling the aeration rate

    Silva, S.S.; Ribeiro, J.D.; Felipe, M.G.A. [Faculty of Chemical Enginering of Lorena (Brazil); Vitolo, M. [Univ. of Sao Paulo (Brazil)

    1997-12-31

    Batch fermentations of sugar cane bagasse hemicellulosic hydrolysate treated for removing the inhibitors of the fermentation were performed by Candida guilliermondii FTI 20037 for xylitol production. The fermentative parameters agitation and aeration rate were studied aiming the maximization of xylitol production from this agroindustrial residue. The maximal xylitol volumetric productivity (0.87 g/L {center_dot} h) and yield (0.67 g/g) were attained at 400/min and 0.45 v.v.m. (K{sub L}a 27/h). According to the results, a suitable control of the oxygen input permitting the xylitol formation from sugar cane bagasse hydrolysate is required for the development of an efficient fermentation process for large-scale applications. 20 refs., 2 figs.

  19. Subterranean production of neutrons, $^{39}$Ar and $^{21}$Ne: Rates and uncertainties

    Šrámek, Ondřej; McDonough, William F; Mukhopadhyay, Sujoy; Peterson, R J

    2015-01-01

    Accurate understanding of the subsurface production of radionuclide $^{39}$Ar rate is necessary for argon dating techniques and noble gas geochemistry of the shallow and the deep Earth, and is also of interest to the WIMP dark matter experimental particle physics community. Our new calculations of subsurface production of neutrons, $^{21}$Ne, and $^{39}$Ar take advantage of the best available tools of nuclear physics to obtain reaction cross sections and spectra (TALYS) and to evaluate neutron propagation in rock (MCNP6). We discuss our method and results in relation to previous studies and show the relative importance of various neutron, $^{21}$Ne, and $^{39}$Ar nucleogenic production channels. Uncertainty in nuclear reaction cross sections, which is the major contributor to overall calculation uncertainty, is estimated from variability in existing experimental and library data. Depending on selected rock composition, on the order of $10^7$-$10^{10}$ {\\alpha} particles are produced in one kilogram of rock pe...

  20. High accuracy tritium measurement for the verification of the tritium production rate calculations with MCNPX

    This paper presents high accuracy tritium production rate measurement results compared with calculations using the MCNPX Monte Carlo particle transport code. The experimental results are regarded as reference values for a new passive technique based on the secondary charged particle activation method developed for measuring the tritium production rate in the test blanket modules of the ITER Tokamak. The 16O(t,n)18F reaction, which is one of the possible tritium monitor reactions, was also extensively investigated, and the experimentally determined reaction rates were compared with simulations. Li2CO3 solution was filled and sealed into quartz ampoules which were irradiated in the Training Reactor of the Budapest University of Technology and Economics. The amount of 18F was determined using γ-spectroscopy. Then the precise tritium measurements were carried out in the Hertelendi Laboratory of Environmental Studies using the 3H–3He ingrowth method, where the 3He produced during the storage time is measured by a static noble gas mass spectrometer (VG-5400). The HT/HTO ratio in the irradiated aqueous solutions was found to be 0.1323±0.0034. Based on the comparison of the measurements and the simulations it was pointed out that the model calculations underestimate the reaction rate of both the 6Li(n,t)α and the 16O(t,n)18F reactions by 5–10% and 15%, respectively. -- Highlights: ► Tritium measurements for verifying the 6Li6(n, t)α reaction rate calculated by MCNPX. ► The HT/HTO ratio was determined in the neutron irradiated aqueous solution of Li2CO3. ► The reaction rate of 16O(t,n)18F was measured in thermal neutron spectrum

  1. Growth rates and production of heterotrophic bacteria and phytoplankton in the North Pacific subtropical gyre

    Jones, David R.; Karl, David M.; Laws, Edward A.

    1996-10-01

    In field work conducted at 26°N, 155°W, in the North Pacific subtropical gyre, phytoplankton growth rates μp estimated from 14C labeling of chlorophyll a (chl a) averaged approximately one doubling per day in the euphotic zone (0-150 m). Microbial (microalgal plus heterotrophic bacterial) growth rates μm calculated from the incorporation of 3H-adenine into DNA were comparable to or exceeded phytoplankton growth rates at most depths in the euphotic zone. Photosynthetic rates averaged 727 mg C m -2 day -1 Phytoplankton carbon biomass, calculated from 14C labeling of chl a, averaged 7.2 mg m -3 in the euphotic zone. Vertical profiles of particulate DNA and ATP suggested that no more than 15% of particulate DNA was associated with actively growing cells. Heterotrophic bacterial carbon biomass was estimated from a two-year average at station ALOHA (22°45'N, 158°W) of flow cytometric counts of unpigmented, bacteria-size particles which bound DAPI on the assumption that 15% of the particles were actively growing cells and that heterotrophic bacterial cells contained 20 fg C cell -1 The heterotrophic bacterial carbon so calculated averaged 1.1 mg m -3 in the euphotic zone. Heterotrophic bacterial production was estimated to be 164 mg C m -2 day -1 or 23% of the calculated photosynthetic rate. Estimated heterotrophic bacterial growth rates averaged 0.97 day -1 in the euphotic zone and reached 4.7 day - at a depth of 20 m. Most heterotrophic bacterial production occurred in the upper 40 m of the euphotic zone, suggesting that direct excretion by phytoplankton, perhaps due to photorespiration or ultraviolet light effects, was a significant source of dissolved organic carbon for the bacteria.

  2. Not Worth the Extra Cost? Diluting the Differentiation Ability of Highly Rated Products by Altering the Meaning of Rating Scale Levels

    Meissner, Martin; Heinzle, Stefanie Lena; Decker, Reinhold

    2013-01-01

    Over the last decade, the use of rating scales has grown in popularity in various fields, including customer online reviews and energy labels. Rating scales convey important information on attributes of products or services that consumers evaluate in their purchase decisions. By applying multidim...

  3. Gas Generation Rates as an Indicator for the Long Term Stability of Radioactive Waste Products

    Pursuant to the 'Act on the Peaceful Utilization of Atomic Energy and the Protection against its Hazards' (Atomic Energy Act) the Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz, BfS) is legally responsible for the construction and operation of federal facilities for the disposal of radioactive waste. Within the scope of this responsibility, particular due to par. 74(1) Ordinance on Radiation Protection, BfS defines all safety-related requirements on waste packages envisaged for disposal, establishes guidelines for the conditioning of radioactive waste and approves the fulfillment of the waste acceptance requirements within the radioactive waste quality control system. BfS also provides criteria to enable the assessment of methods for the treatment and packaging of radioactive waste to produce waste packages suitable for disposal according to par. 74(2) Ordinance on Radiation Protection. Due to the present non-availability of a repository in Germany, quality control measures for all types of radioactive waste products are carried out prior to interim storage with respect to the future disposal. As a result BfS approves the demonstrated properties of the radioactive waste packages and confirms the fulfillment of the respective requirements. After several years of storage the properties of waste packages might have changed. By proving, that such changes have no significant impact on the quality of the waste product, the effort of requalification could be minimized. Therefore, data on the long-term behavior of radioactive waste products need to be acquired and indicators to prove the long-term stability have to be quantified. Preferably, such indicators can be determined easily with non-destructive methods, even for legacy waste packages. A promising parameter is the gas generation rate. The relationship between gas generation rate and long term stability is presented as first result of an ongoing study on behalf of BfS. Permissible gas

  4. Direct measurement of ozone production rates in Houston in 2009 and comparison with two estimation methods

    M. Cazorla

    2011-10-01

    Full Text Available Ozone production rates, P(O3, were measured directly using the Penn State Measurement of Ozone Production Sensor (MOPS during the Study of Houston Atmospheric Radical Precursors (SHARP 2009. Measured P(O3 peaked in the late morning, with values between 15 ppbv h−1 and 100 ppbv h−1, although values of 40–80 ppbv h−1 were typical for higher ozone days. These measurements were compared against ozone production rates calculated using measurements of hydroperoxyl (HO2, hydroxyl (OH, and nitric oxide (NO radicals, called "calculated P(O3". The same comparison was done using modeled radicals obtained from a box model with the RACM2 mechanism, called "modeled P(O3". Measured and calculated P(O3 had similar peak values but the calculated P(O3 tended to peak earlier in the morning when NO values were higher. Measured and modeled P(O3 had a similar dependence on NO, but the modeled P(O3 was only half the measured P(O3. This difference indicates possible missing radical sources in the box model with the RACM2 mechanism and thus has implications for the ability of air quality models to accurately predict ozone production rates.

  5. Low LET radiation dose rate effect and free radical production and survival

    The authors previously published the finding that LD-50/30 varied with the reciprocal cube root of x- or gamma-radiation dose rate in a number of studies by others in mice and rats. Human skin erythema also appeared to fit the relationship. Broyles subsequently employed a modification of the relationship with particular interest in dose rates of less than 6 rad per day. Having noted a deflection of actual data from reciprocal cube root- predicted values at higher dose rates in the earlier utilized studies, they modified the original relationship with the finding of a better fit of data from a broad variety of endpoints to predicted values. These end-points include E. Coli survival, murine lens opacification, spermatogonia depletion, and abnormal liver anaphases, skin erythema in man and swine, LD 50/4 in mice and rats, LD-50/30 in mice, rats, and swine, and LD-50/60 in sheep. ED-50 specific loss of dose-rate effect appears to occur with several of the quoted parameters at very high dose rates (greater than 1000 rad per minute). The possible role of oxygen depletion and free radical production and survival

  6. Dose rate distribution for products irradiated in a semi-industrial irradiation plant. 2nd. Stage

    The model of the absorbed dose distribution in a bulk product in a semi industrial irradiation plant is presented. In this plant the products are subject to a dynamic irradiation process: single-plaque, single-direction and four-pass. The additional two passes, also one on each side of the plaque, serve to minimize the lateral dose variation as well of the depth-dose non-uniformity. The second stage of this model studies the effect of the metallic carriers of the product and its results are compared with the experimental measurements. The influence of the inhomogeneity is analyzed. For the case of static irradiation process carried out together with the dynamic irradiation process the effect of the metallic carriers of the products behind the product is analyzed. For the case of static irradiation alone, the effect of the metallic tables where the dosimeters are set is modeled and the calculated absorbed dose rate is compared with the experimental measurement. (author)

  7. The influence of the concentration of atmospheric radon decay products on the environmental radiation dose rate

    It has been occasionally found from an area monitoring data obtained at an atomic power station that the daily periodical change of the environmental radiation dose rate appeared near the ground surface. It is suggested that the variation has resulted from the change of atmospheric radon concentration and that it has also depended on the geographical features of the observation point. The change component has been estimated to be up to nearly 30 percent of the environmental radiation dose rate from monitoring data. To investigate precisely the phenomena, observation was performed near a monitoring station and at other area in Fukui Prefecture during the summer. The dose rate from terrestrial radiation was 42 nGy/h at the Natasho in Ooi Town and was 30 nGy/h at the Kaminaka in Wakasa Town. The concentration of radon decay products in the air was 0.5 - 30 Bq/m3 at the Natasho site and was 1 - 10 Bq/m3 at the Kaminaka site. From the concentration of radon decay products in the atmosphere, the dose rate was respectively estimated to be 0-7.0 nGy/h at the Natasho site, and to be 0-5.5 nGy/h at the Kaminaka site. Furthermore, 0.26(nGy/h)/(Bq/m3) and 0.56(nGy/h)/(Bq/m3) were estimated as the dose rate conversion factor of radon concentration in the air at the Natasho site and at the Kaminaka site, respectively. (author)

  8. Effects of biofertilizer rates on the structural, morphogenetic and productive characteristics of Piatã grass

    Marco Antonio Previdelli Orrico Junior

    2012-06-01

    Full Text Available The objective of this study was to investigate the influence of different levels of biofertilizers from cattle and swine manure on the structural, morphogenetic and productive characteristics of Brachiaria brizantha cv. Piatã. The experiment was arranged in a completely randomized factorial design with split plots. The plots were defined by eight treatments: two biofertilizers (cattle and swine, four levels (0, 100, 200 and 300 kg N.ha-1 and subplots by four different cutting periods. The cutting for plant uniformity was performed at 45 days after sowing at 15 cm above the soil surface. The biofertilizeres were applied in a single level, after the cutting of plants, in rates of 0, 0.23 and 0.19, 0.45 and 0.38, 0.68 and 0.57 liters pot-1 for the biofertilizers from cattle and swine manure, respectively. These rates were also equivalent to levels of 0, 100, 200 and 300 kg N.ha-1. There was no significant difference between the types of biofertilizers as there was no interaction between them and the different levels, hence both biofertilizers could be applied without any loss of nutrient intake by the plants used in this experiment. There was a significant difference between the production of green and dry matter, the leaf appearance rate, phyllochron, leaf and pseudostem elongation rates, number of green leaves, final leaf length, number and weight of tillers, according to the increase of nitrogen rates, following linear prediction model. Effect of the cutting periods was also observed, once the plants harvested during the summer presented greater performance of structural and morphogenetic characteristics.

  9. Specific light uptake rates can enhance astaxanthin productivity in Haematococcus lacustris.

    Lee, Ho-Sang; Kim, Z-Hun; Park, Hanwool; Lee, Choul-Gyun

    2016-05-01

    Lumostatic operation was applied for efficient astaxanthin production in autotrophic Haematococcus lacustris cultures using 0.4-L bubble column photobioreactors. The lumostatic operation in this study was performed with three different specific light uptake rates (q e) based on cell concentration, cell projection area, and fresh weight as one-, two- and three-dimensional characteristics values, respectively. The q e value from the cell concentration (q e1D) obtained was 13.5 × 10(-8) μE cell(-1) s(-1), and the maximum astaxanthin concentration was increased to 150 % compared to that of a control with constant light intensity. The other optimum q e values by cell projection area (q e2D) and fresh weight (q e3D) were determined to be 195 μE m(-2) s(-1) and 10.5 μE g(-1) s(-1) for astaxanthin production, respectively. The maximum astaxanthin production from the lumostatic cultures using the parameters controlled by cell projection area (2D) and fresh weight (3D) also increased by 36 and 22 % over that of the controls, respectively. When comparing the optimal q e values among the three different types, the lumostatic cultures using q e based on fresh weight showed the highest astaxanthin productivity (22.8 mg L(-1) day(-1)), which was a higher level than previously reported. The lumostatic operations reported here demonstrated that more efficient and effective astaxanthin production was obtained by H. lacustris than providing a constant light intensity, regardless of which parameter is used to calculate the specific light uptake rate. PMID:26873706

  10. Methane production rates from natural organics of glacial lake clay and granitic groundwater

    Engineered barrier materials are an integral part of the proposed Canadian concept for the disposal of used nuclear fuel or high level waste. Components of these barriers, such as the buffer and backfill clays surrounding the waste containers in a vault, and granitic groundwater, naturally contain small quantities of organic material (up to about 1.2 wt%). Despite high temperatures, space and water limitations and radiation effects, the question remains whether gas could be produced from these organics as a result of biological processes. Degradation of organic carbon by microbes can produce gases such as carbon dioxide (C02) and methane (CH4). This work demonstrates that methane is produced in natural systems containing 2. In deep fracture zone groundwater, the largest methane production rate was 0.19 mole %/day or 5 μg CH4/L groundwater per day, at STP. This can be compared with the methane production rate of 1 μg CH4/(kg clay · day) at STP in an earlier experiment containing added organic material. Using this rate of 5 pg CH4/(L groundwater · day) (3.75 μg C/(L groundwater · day)), all of the organic C in the groundwater, assuming it is equally bioavailable, would have been converted to CH4 during the timeframe of this experiment. Enhanced methane production occurred with an increase in natural organic carbon, an increase in the microbe population and with the addition of Fe. Steady-state methane production rates of 10 to 25 μg CH4/ L groundwater per day have been repeatedly observed in clay-free systems. The effects of microbial metabolism, the requirement for a facilitating consortium, the Eh, the pH, the salinity, the groundwater sulphate concentration, the presence of methanotrophs and the sorption effects of clay interlayers are discussed as possible explanations for the inhibition of methanogenesis and methane production in the presence of clay and crushed granite. (author). 49 refs., 11 tabs., 12 figs

  11. Comparing Occupational Health and Safety Management System Programming with Injury Rates in Poultry Production.

    Autenrieth, Daniel A; Brazile, William J; Douphrate, David I; Román-Muñiz, Ivette N; Reynolds, Stephen J

    2016-01-01

    Effective methods to reduce work-related injuries and illnesses in animal production agriculture are sorely needed. One approach that may be helpful for agriculture producers is the adoption of occupational health and safety management systems. In this replication study, the authors compared the injury rates on 32 poultry growing operations with the level of occupational health and safety management system programming at each farm. Overall correlations between injury rates and programming level were determined, as were correlations between individual management system subcomponents to ascertain which parts might be the most useful for poultry producers. It was found that, in general, higher levels of occupational health and safety management system programming were associated with lower rates of workplace injuries and illnesses, and that Management Leadership was the system subcomponent with the strongest correlation. The strength and significance of the observed associations were greater on poultry farms with more complete management system assessments. These findings are similar to those from a previous study of the dairy production industry, suggesting that occupational health and safety management systems may hold promise as a comprehensive way for producers to improve occupational health and safety performance. Further research is needed to determine the effectiveness of such systems to reduce farm work injuries and illnesses. These results are timely given the increasing focus on occupational safety and health management systems. PMID:27409413

  12. Nitrogen metabolism and protozoa production rate in cattle fed on diet containing protected protein

    Nitrogen metabolism and protozoa production rate using 14C-choline as marker were studied on 9 adult male crossbred (Tharparker x Brown Swiss) rumen fistulated animals divided into 3 groups (A, B and C). All the animals were fed concentrate mixture and wheatstraw. However, groundnut cake (GNC) in concentrate mixture was untreated in group A, 50 per cent formaldehyde treated in group B and 100 per cent formaldehyde treated in group C. Although, DM intake was similar in these groups but water intake was significantly (P<0.05) higher in control group. Total-N, ammonia-N and blood urea were significantly lower in group B and C as compared to group A. Apparent CP digestibility was not affected by addition of formaldehyde treated GNC at 50 and 100 per cent levels. However, N balances increased significantly (P<0.05) due to addition of protected protein in diet. Protozoal pool as well as production rate were significantly (P<0.01) decreased due to formaldehyde treatment of GNC protein. Thus addition of formaldehyde treated GNC in diets decreased ammonia and protozoa production but increased N retention in groups B and C. (author). 27 refs., 3 tabs., 2 figs

  13. The rate of visitation by Amazilia fimbriata (Apodiformes: Trochilidae influences seed production in Tillandsia stricta (Bromeliaceae

    Caio C.C. Missagia

    2015-06-01

    Full Text Available Legitimate flowers visitors pollinate the flower during the visit and thus influence the production of fruits and seeds. We tested whether the visitation rate of potential pollinators is associated with the amount of seeds per fruit produced by the self-compatible bromeliad Tillandsia stricta (Bromeliaceae. We determined whether hummingbirds are legitimate visitors by testing for a correlation between visits and pollination (seed production at the Guapiaçú Ecological Reserve (Reserva Ecológica de Guapiaçú, state of Rio de Janeiro. We tested 30 flowers, five of which were also monitored to test the possibility of spontaneous self-pollination. The remaining 25 flowers were exposed to floral visitors. Twenty-two flowers formed fruits and seeds, from which three formed seeds without floral visits. The hummingbird Amazilia fimbriata (Gmelin, 1788 was the only legitimate visitor. The average number (± standard deviation of seeds was 27 units (±15 per fruit. The floral visitation rate by A. fimbriata was 6.6 (±3.4 visits/per flower. The number of floral visits and the amount of seed produced were positively correlated (r² = 0.58, p < 0.01. Thus, A. fimbriata is a legitimate floral visitor of T. stricta, and influences seed production per fruit in this bromeliad.

  14. Calibration of cosmogenic 3He and 10Be production rates in the High Tropics

    Blard, Pierre-Henri; Martin, Léo; Lavé, Jérôme; Charreau, Julien; Condom, Thomas; Lupker, Maarten; Braucher, Régis; Bourlès, Didier

    2014-05-01

    It is critical to refine both the accuracy and the precision of the in situ cosmogenic dating tool, especially for establishing reliable glacial chronologies that can be compared to other paleoclimatic records. Recent cross-calibrations of cosmogenic 3He in pyroxene and 10Be in quartz [1, 2] showed that, both at low (1300 m) and high elevation (4850 m), the 3He/10Be production ratio was probably ~40% higher than the value of ~23 initially defined in the 90's. This recent update is consistent with the last independent determinations of the sea level high latitude production rates of 10Be and 3He, that are about 4 and 125 at.g-1.yr-1, respectively [e.g. 3, 4]. However, major questions remain about these production rates at high elevation, notably because existing calibration sites for both 3He and 10Be are scarce above 2000 m. It is thus crucial to produce new high precision calibration data at high elevation. Here we report cosmogenic 10Be data from boulders sampled on a glacial fan located at 3800 m in the Central Altiplano (Bolivia), whose age is independently constrained by stratigraphic correlations and radiocarbon dating at ca. 16 ka. These data can be used to calibrate the production rate of 10Be at high elevation, in the Tropics. After scaling to sea level and high latitude, these data yield a sea level high latitude P10 ranging from 3.8 to 4.2 at.g-1.yr-1, depending on the used scaling scheme. These new calibration data are in good agreement with recent absolute and cross-calibration of 3He in pyroxenes and 10Be in quartz, from dacitic moraines located at 4850 m in the Southern Altiplano (22° S, Tropical Andes) [2,5]. The so-obtained 3He/10Be production ratio of 33.3±0.9 (1σ) combined with an absolute 3He production rate locally calibrated in the Central Altiplano, at 3800 m, indeed yielded a sea level high latitude P10 ranging from 3.7±0.2 to 4.1±0.2 at.g-1.yr-1, depending on the scaling scheme [2,5]. These values are also consistent with the 10Be

  15. Estimation of radiation dose rates around medical isotopes production facility of Cyclotron

    The demand of the radio isotopes for medical application is increasing day by day. Cyclotron is a tool for production of these proton rich isotopes which are termed a SPECT and PET isotopes. The irradiated hot targets from a cyclotron bunker are transferred to the hot cells for processing chemically to obtain the required radioisotope. A pre estimation of dose rates at various locations of the hot cells with worst and normal operation conditions is essential. An exercise of estimation of worst cases also gives an idea about the dose to the workers and necessary preparedness without compromising on the regulatory aspects. 18F, 67Ga, 201Tl are the most important isotopes that will be produced in medical cyclotron. They are produced by bombarding proton on suitable target materials. The activated targets transferred to the hot cells from irradiated machine/production bunker. Chemist has to work at hot cells for chemical synthesis for 18F to form FDG. For SPECT isotope production target has to under go two stages of chemical synthesis. The dose rate estimation around the hot cells will give the estimation of dose to the radiation workers. In addition to medical isotope the other materials surrounding the target also get activated because of proton or neutron activation. The dose estimation depends on the total activity that is produced and the period of time for entire the chemical processing. The dose rate are estimated by using suitable expressions considering normal and worst scenario conditions. A procedure and a case was discussed and result shown both for normal and worse scenario case. It is observed that not only shielding many other factors like ventilation etc played important role. A case study was made and results are shown with the suggestive preventive measures. (author)

  16. Production of coercive as-forged Pr Fe B Cu magnets using multiple hot deformation rates

    Alloys of Pr Fe B Cu have been used to produce permanent magnets by hot deformation at 750 deg C under vacuum. Blocks of alloy were cut and placed in copper tubes with boron nitride coated stainless steel over the ends. It was fount that the size of the block used was critical as the tube split if the block was too large. It was also necessary to have the ends of the block parallel to avoid buckling of the sample during pressing. Permanent magnetic properties were achieved without the need for heat treatment by controlling the deformation rate during hot pressing. The best properties achieved were: maximum energy product = 176 k J m-3, remanence = 980 m T and intrinsic coercivity = 815 k Am-1, for an alloy of Pr17.5 Fe76 Cu1.5 B5 (atomic%) pressed at a rate of 1.75 x 10-2 s-1 up to 60% height reduction and then 4.7 x 10-2 s-1 up to 89%. The slower height reduction rate for the first stage of deformation seemed to give improved crystal alignment leading to an increase remanence and maximum energy product. Using a total height reduction of ∼85% it was found that the highest Pr content alloy gave the best remanence, maximum energy product and squareness, whereas the lowest Pr content gave the best intrinsic coercivity. This is believed to be due to the higher proportion of liquid phase during pressing, giving improved crystal alignment but not letting the grains crack to give a grain refinement and an increased intrinsic coercivity. (author)

  17. UTILITY OF THE METHOD T.H.M. (MACHINE - HOUR - RATE PRODUCTION CENTURY PROCESS AUTOMATION

    Cristina-Otilia, ȚENOVICI

    2014-11-01

    Full Text Available The method T.H.M. (machine - hour - rate gives greater accuracy in the factories or departments, where production is largely by machinery. In the specialty literature, the notion of price - the time - the car is defined as "œa rate calculated by dividing the budgeted or estimated overhead or labour and overhead cost attributable to a machine or group of similar machines by the appropriate number of machine hours. The hours may be the number of hours for which the machine or group is expected to be operated, the number of hours which would relate to normal working for the factory, or full capacity". In a highly mechanised cost centre, majority of the overhead expenses are incurred on account of using the machine, such as, depreciation, power, repairs and maintenance, insurance, etc. This method is currently offering the most equitable basis for absorption of overheads in machine intensive cost centres.

  18. Thermal right-handed neutrino production rate in the non-relativistic regime

    Laine, M

    2011-01-01

    We consider the next-to-leading order thermal production rate of heavy right-handed neutrinos in the non-relativistic regime m_top < pi*T << M, where m_top refers to the electroweak scale. Rephrasing the problem in an OPE language and making use of different techniques than a previous analysis by Salvio et al, we confirm the general structure of their result and many of the coefficients. We also extend the analysis to the next order in the non-relativistic expansion, thereby revealing the leading non-trivial momentum dependence, as well as to NNLO in couplings, revealing the leading sensitivity to thermal resummations. Our results are expressed as a sum of simple "master" structures, which renders them a suitable starting point for determining the next-to-leading order rate also in the relativistic regime pi*T ~ M.

  19. Effect of Stirrer Speed and Aeration Rate on the Production of Glucose Oxidase by Aspergillus niger

    Jafari A.R.

    2007-01-01

    Full Text Available Dissolved oxygen tension and shear stress as two very important factors in fungal fermentation were studied in the batch cultures of Aspergillus niger. The intention was to maximize the total activity of glucose oxidase produced in a 5-1 bench-top bioreactor. 300 rpm found to be optimum for enzyme production, however in higher mixing rates higher growth was achieved. The maximum activity of glucose oxidase was obtained in 1.5 vvm while the best aeration rate for growth was 2 vvm. Glucose oxidase with the activity of 548 U mL-1 was produced in 1.5 vvm and 300 rpm as the optimum conditions.

  20. Dosimetric systems of high dose, dose rate and dose uniformity in food and medical products

    In the Instituto Peruano de Energia Nuclear (IPEN) we use the chemical dosimetry Astm-E-1026 Fricke as a standard dosimetric system of reference and different routine dosimetric systems of high doses, according to the applied doses to obtain the desired effects in the treated products and the doses range determined for each type of dosimeter. Fricke dosimetry is a chemical dosimeter in aqueous solution indicating the absorbed dose by means an increase in absorbance at a specific wavelength. A calibrated spectrophotometer with controlled temperature is used to measure absorbance. The adsorbed dose range should cover from 20 to 400 Gy, the Fricke solution is extremely sensitive to organic impurities, to traces of metal ions, in preparing chemical products of reactive grade must be used and the water purity is very important. Using the referential standard dosimetric system Fricke, was determined to March 5, 2013, using the referential standard dosimetric system Astm-1026 Fricke, were irradiated in triplicate Fricke dosimeters, to 5 irradiation times (20; 30; 40; 50 and 60 seconds) and by linear regression, the dose rate of 5.400648 kGy /h was determined in the central point of the irradiation chamber (irradiator Gamma cell 220 Excel), applying the decay formula, was compared with the obtained results by manufacturers by means the same dosimetric system in the year of its manufacture, being this to the date 5.44691 kGy /h, with an error rate of 0.85. After considering that the dosimetric solution responds to the results, we proceeded to the irradiation of a sample of 200 g of cereal instant food, 2 dosimeters were placed at the lateral ends of the central position to maximum dose and 2 dosimeters in upper and lower ends as minimum dose, they were applied same irradiation times; for statistical analysis, the maximum dose rate was 6.1006 kGy /h and the minimum dose rate of 5.2185 kGy /h; with a dose uniformity of 1.16. In medical material of micro pulverized bone for

  1. Inner-product of strain rate vector through direction cosine in coordinates for disk forging

    ZHAO De-wen; JIN Wen-zhong; WANG Lei; LIU Xiang-hua

    2006-01-01

    A new linear integration for plastic power was proposed. The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector, and then its direction cosines were determined by the ratio of coordinate increments. Furthermore, inner-product of the vector for plastic power was term integrated by term and summed. Thereafter, through a formula for determination of bulge an analytical solution of stress effective factor was obtained. Finally, through compression tests, the calculated results of above formula were compared with those of Avitzur's approximate solution and total indicator readings of the testing machine. It is indicated that the calculated compression forces are basically in agreement with the measured ones if the pass reduction is less than 13.35%.However, when the reduction gets up to 25.34% and 33.12%, the corresponding errors between the calculated and measured results also get up to 6% and 13.5%, respectively.

  2. The relationship between thyroxine secretion rate and egg production in chicken

    An experiment was carried out in 24 female White Leghorn Chickens by using 131I as tracer. The chickens were initially and intraperitoneally injected with 10μCi of 131I and then counted by means of a Gamma Well Type Scintillation Counter every 48 hours. A dose of 0,3 μg of thyroxine per 100 gr body weight was given as the first administration. After every two administrations of similar dose, the dose of the thyroxine was increased by 0,1 μg/100g body weight until the thyroxine secretion rate was reached. The injections were given in the neck region subcutaneously. The thyroxine secretion rate was found to be within the range from 0,5μg to 0,8μg per 100 g body weight. It also showed that the higher the thyroxine secretion rate, the higher the egg production became. This phenomenon occured both with the 7 and 9 months old chickens. However there was neither ralationship between the thyroxine secretion rate and the weight of eggs produced nor with the body weight of the chickens themselves. (author)

  3. Rheological behavior of physicochemical sludges during methanogenesis suppression and hydrogen production at different organic loading rates.

    Méndez-Contreras, Juan Manuel; López-Escobar, Luis A; Martínez-Hernández, Sergio; Cantú-Lozano, Denis; Ortiz-Ceballos, Angel I

    2016-06-01

    This study investigated the rheological behavior of raw physicochemical sludges and sludges that were digested at different organic loading rates (OLRs) (1, 5, 10 and 15 gVS L(-1) d(-1)) during methanogenesis suppression to produce hydrogen anaerobically. The Herschel-Bulkley model was used to describe the rheology of these sludges with specific properties. The results indicate that the Herschel-Bulkley model adequately described the rheology ([Formula: see text] ≠ 0) of this type of fluids (R(2) > 0.98). In addition, the raw physicochemical sludges and those that were digested at different OLRs had dilatant behaviors (n > 1), which increased with increasing OLR. These results identified the apparent viscosity, yield stress, pH and OLR conditions that allow for the production and suppression of methane, as well as the conditions that guarantee the production of hydrogen. PMID:26943338

  4. Heat production rate from radioactive elements in igneous and metamorphic rocks in eastern desert, Egypt

    Radioactive heat - production data of igneous and metamorphic rocks cropping out from the eastern desert are presented. Samples were analysed using low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 Μ Wm-3 (granite). In metamorphic rocks it varies from 0.28 (serpentinite) to 0.91 (metagabroo) Μ W.m-3. The contribution due to U is about (51%), whereas that of Th (31%) and (18%) by K. The corresponding values in igneous rocks are 76%: 19%: 5%, respectively. The calculated values showed good agreement with global values expect in some areas contained granite rocks

  5. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt

    Abbady, Adel G.E. [Physics department, Faculty of science, South Valley University, Qena (Egypt)]. E-mail: abbady@mailcity.com; El-Arabi, A.M. [Physics department, Faculty of science, South Valley University, Qena (Egypt)]. E-mail: elarabi21@yahoo.com; Abbady, A. [Physics department, Faculty of science, South Valley University, Qena (Egypt)

    2006-01-01

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 {mu}W m{sup -3} (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 {mu}W m{sup -3} (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites.

  6. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 μW m-3 (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 μW m-3 (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites

  7. Spectral conversion of light for enhanced microalgae growth rates and photosynthetic pigment production.

    Mohsenpour, Seyedeh Fatemeh; Richards, Bryce; Willoughby, Nik

    2012-12-01

    The effect of light conditions on the growth of green algae Chlorella vulgaris and cyanobacteria Gloeothece membranacea was investigated by filtering different wavelengths of visible light and comparing against a model daylight source as a control. Luminescent acrylic sheets containing violet, green, orange or red dyes illuminated by a solar simulator produced the desired wavelengths of light for this study. From the experimental results the highest specific growth rate for C. vulgaris was achieved using the orange range whereas violet light promoted the growth of G. membranacea. Red light exhibited the least efficiency in conversion of light energy into biomass in both strains of microalgae. Photosynthetic pigment formation was examined and maximum chlorophyll-a production in C. vulgaris was obtained by red light illumination. Green light yielded the best chlorophyll-a production in G. membranacea. The proposed illumination strategy offers improved microalgae growth without resorting to artificial light sources, reducing energy use and costs of cultivation. PMID:23023239

  8. Sodium aerosol release rate and nonvolatile fission product retention factor during a sodium-concrete reaction

    This paper reports on a series of tests conducted to study the mechanical release behavior of sodium aerosols containing nonvolatile fission products during a sodium-concrete reaction in which release behavior due to hydrodynamic breakup of the hydrogen bubble is predominant at the sodium pool surface. In the tests, nonradioactive materials, namely, strontium oxide, europium oxide, and ruthenium particles, whose sizes range from a few microns to several tens of microns, are used as nonvolatile fission product stimulants. The following results are obtained: The sodium aerosol release rate during the sodium-concrete reaction is larger than that of natural evaporation. The difference, however, becomes smaller with increasing sodium temperature: nearly ten times smaller at 400 degrees C and three times at 700 degrees C. The retention factors for the nonvolatile materials in the sodium pool increase to the range of 0.5 to 104 with an increase in the sodium temperature from 400 to 700 degrees C

  9. Fission product release rates measured during in-pile fuel damage tests

    A series of severe fuel damage tests is being performed in the Power Burst Facility (PBF) at the Idaho National Engineering Laboratory for the US Nuclear Regulatory Commission and an international group of sponsors. A major objective of the first phase of this program is to measure the release, transport, and deposition of fission products during in-pile tests similar to the accident which occurred at the Three Mile Island Unit-2 reactor. This paper describes the measured release rates (bundle inventory fractions released per minute) for fission product isotopes found in grab samples collected from the test effluent during the Severe Fuel Damage Scoping Test (SFD-ST) and Severe Fuel Damage Test 1-1 (SFD 1-1). These measured in-pile data are compared with data from the previous out-of-pile research

  10. Entanglement entropy and mutual information production rates in acoustic black holes.

    Giovanazzi, Stefano

    2011-01-01

    A method to investigate acoustic Hawking radiation is proposed, where entanglement entropy and mutual information are measured from the fluctuations of the number of particles. The rate of entropy radiated per one-dimensional (1D) channel is given by S=κ/12, where κ is the sound acceleration on the sonic horizon. This entropy production is accompanied by a corresponding formation of mutual information to ensure the overall conservation of information. The predictions are confirmed using an ab initio analytical approach in transonic flows of 1D degenerate ideal Fermi fluids. PMID:21231730

  11. Tritium production-rate measurement techniques developed at FNS/JAERI

    The tritium production-rate (TPR) is a very important neutronic parameter in the D-T fusion blanket research. The following five techniques for the measurement of TPR have been developed at FNS/JAERI: (1) Subtraction method using a pair of Li-glass scintillators, (2) Indirect method using a small sphere NE213 scintillator, (3) Liquid scintillation method with Li2O pellet, (4) Liquid scintillation method with Li2O plate/block (zonal method), and (5) LiF TLD self-irradiation method. This paper describes these methods, comparison of their features, and their typical results for the blanket benchmark experiments at FNS

  12. Developments of regional gross domestic product and the unemployment rate in Romania during 2000 - 2012

    Schonauer (Sacală Corina

    2015-12-01

    Full Text Available Economic development of territorial units can be characterized by measuring the ability of producing goods and services and by measuring labor force in the area. The capacity of producing goods and services is measured by calculating the gross domestic product indicator. This article presents a comparative analysis of the evolution of regional GDP and the ILO unemployment rate at the level of the eight regions in Romania for a period of 13 years. The presented data come from the National Institute of Statistics of Romania.

  13. THE BROAD-BAND CCD PHOTOMETRY AND DUST PRODUCTION RATES OF COMET HALE-BOPP

    Huang Keliang; Hu Jingyao; Zhou Hongnan

    2000-01-01

    Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/dt~1.5×105 kgs-1, Rn~35.5km, and Mn~5.65×1016kg.

  14. The broad-band CCD photometry and dust production rates of comet Hale-Bopp

    黄克谅; 胡景耀; 周洪楠

    2000-01-01

    Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60 cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/df ~ 1.5 × 105 kgs-1, Rn~35.5 km, and Mn~5.65×1016 kg.

  15. The broad-band CCD photometry and dust production rates of comet Hale-Bopp

    2000-01-01

    Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60 cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/dt~1.5×105 kgs-1, Rn~35.5 km, and Mn~5.65×1016 kg.

  16. Land race as a source for improving photosynthetic rate and productivity in cowpea (Vigna unguiculata W.)

    Suma Biradar, P.M. Salimath and B.C.Patil

    2010-01-01

    Cowpea is an important grain legume of arid and semiarid regions of Asia and Africa. Productivity of cowpea is low and stagnant.Conventional breeding approaches aimed at improvement of yield per se have not been successful so far in breaking the yieldbarrier. Manipulation of physiological processes such as photosynthesis is expected to yield positive results. A land race ‘Goalocal’ with a very high photosynthetic rate was used to improve this trait in selected cultivars, C-152, KM-1 and V-118...

  17. Rate equation network for baryon production in high energy nuclear collisions

    We develop and solve a network of rate equations for the production of baryons and antibaryons in high energy nuclear collisions. We include all members of the baryon octet and decuplet and allow for transformations among them. This network is solved during a relativistic 2+1 hydrodynamical expansion of the of the hot matter created in the collision. As an application we compare to the number of protons, Λ's, negative cascades, and Ω baryons measured at midrapidity in central collisions of gold nuclei at 65 GeV per nucleon at the Relativistic Heavy Ion Collider (RHIC)

  18. SIZE DISTRIBUTION AND RATE OF PRODUCTION OF AIRBORNE PARTICULATE MATTER GENERATED DURING METAL CUTTING

    During deactivation and decommissioning activities, thermal cutting tools, such as plasma torch, laser, and gasoline torch, are used to cut metals. These activities generate fumes, smoke and particulates. These airborne species of matter, called aerosols, may be inhaled if suitable respiratory protection is not used. Inhalation of the airborne metallic aerosols has been reported to cause ill health effects, such as acute respiratory syndrome and chromosome damage in lymphocytes. In the nuclear industry, metals may be contaminated with radioactive materials. Cutting these metals, as in size reduction of gloveboxes and tanks, produces high concentrations of airborne transuranic particles. Particles of the respirable size range (size < 10 microm) deposit in various compartments of the respiratory tract, the fraction and the site in the respiratory tract depending on the size of the particles. The dose delivered to the respiratory tract depends on the size distribution of the airborne particulates (aerosols) and their concentration and radioactivity/toxicity. The concentration of airborne particulate matter in an environment is dependent upon the rate of their production and the ventilation rate. Thus, measuring aerosol size distribution and generation rate is important for (1) the assessment of inhalation exposures of workers, (2) the selection of respiratory protection equipment, and (3) the design of appropriate filtration systems. Size distribution of the aerosols generated during cutting of different metals by plasma torch was measured. Cutting rates of different metals, rate of generation of respirable mass, as well as the fraction of the released kerf that become respirable were determined. This report presents results of these studies. Measurements of the particles generated during cutting of metal plates with a plasma arc torch revealed the presence of particles with mass median aerodynamic diameters of particles close to 0.2 micro

  19. Consensus and Products of Random Stochastic Matrices: Exact Rate for Convergence in Probability

    Bajovic, Dragana; Moura, Jose M F; Sinopoli, Bruno

    2012-01-01

    Distributed consensus and other linear systems with system stochastic matrices $W_k$ emerge in various settings, like opinion formation in social networks, rendezvous of robots, and distributed inference in sensor networks. The matrices $W_k$ are often random, due to, e.g., random packet dropouts in wireless sensor networks. Key in analyzing the performance of such systems is studying convergence of matrix products $W_kW_{k-1}... W_1$. In this paper, we find the exact exponential rate $I$ for the convergence in probability of the product of such matrices when time $k$ grows large, under the assumption that the $W_k$'s are symmetric and independent identically distributed in time. Further, for commonly used random models like with gossip and link failure, we show that the rate $I$ is found by solving a min-cut problem and, hence, easily computable. Finally, we apply our results to optimally allocate the sensors' transmission power in consensus+innovations distributed detection.

  20. Mass transport around comets and its impact on the seasonal differences in water production rates

    Comets are surrounded by a thin expanding atmosphere, and although the nucleus' gravity is small, some molecules and grains, possibly with the inclusion of ices, can get transported around the nucleus through scattering (atoms/molecules) and gravitational pull (grains). Based on the obliquity of the comet, it is also possible that volatile material and icy grains get trapped in regions, which are in shadow until the comet passes its equinox. When the Sun rises above the horizon and the surface starts to heat up, this condensed material starts to desorb and icy grains will sublimate off the surface, possibly increasing the comet's neutral gas production rate on the outbound path. In this paper we investigate the mass transport around the nucleus, and based on a simplified model, we derive the possible contribution to the asymmetry in the seasonal gas production rate that could arise from trapped material released from cold areas once they come into sunlight. We conclude that the total amount of volatiles retained by this effect can only contribute up to a few percent of the asymmetry observed in some comets.

  1. Estimation of Hydrogen Production Rates from Radiolysable Material in Contact with Various Irradiated Fuels

    The storage of irradiated fuel is increasing as many installations are approaching their end of- ife and fuel or fuel-containing remnants from waste or samples are being placed in storage. Often these smaller experimental samples are mounted in epoxide resins or are placed containers with bitumen. It is particularly in combination with these radiolysable materials where the irradiation generates hydrogen that problems arise in longer term storage. The hydrogen generation results in either pressure buildup (with container bloating and eventual failure) or in case of gas release and mixture with air, a detonation. Previous work has examined the Phebus FPT1 bundle encased in resin where it was necessary for both transport and intermediate storage at Cadarache to assess this risk. This work is a first estimation of the radiolysis rates to be expected from various fuels and to assess the range of H2 production from radiolysable material based on the results of the FPT1 Phebus bundle. The first step is to make a correlation of the total activity with the burnup of UO2 fuel. Then using the H2 production rates measured for the Phebus fuel, an estimate of its dependence on fuel burn-up will be made and so help define the necessary design for the foreseen storage time. (author)

  2. Petroleum production at Maximum Efficient Rate Naval Petroleum Reserve No. 1 (Elk Hills), Kern County, California

    This document provides an analysis of the potential impacts associated with the proposed action, which is continued operation of Naval Petroleum Reserve No. I (NPR-1) at the Maximum Efficient Rate (MER) as authorized by Public law 94-258, the Naval Petroleum Reserves Production Act of 1976 (Act). The document also provides a similar analysis of alternatives to the proposed action, which also involve continued operations, but under lower development scenarios and lower rates of production. NPR-1 is a large oil and gas field jointly owned and operated by the federal government and Chevron U.SA Inc. (CUSA) pursuant to a Unit Plan Contract that became effective in 1944; the government's interest is approximately 78% and CUSA's interest is approximately 22%. The government's interest is under the jurisdiction of the United States Department of Energy (DOE). The facility is approximately 17,409 acres (74 square miles), and it is located in Kern County, California, about 25 miles southwest of Bakersfield and 100 miles north of Los Angeles in the south central portion of the state. The environmental analysis presented herein is a supplement to the NPR-1 Final Environmental Impact Statement of that was issued by DOE in 1979 (1979 EIS). As such, this document is a Supplemental Environmental Impact Statement (SEIS)

  3. Hybrid customer requirements rating method for customer-oriented product design using QFD

    Fang Wang; Hua Li; Aijun Liu; Xiao Zhang

    2015-01-01

    Quality function deployment (QFD) is a wel-known customer-oriented product design methodology. Rating the final importance of customer requirements (CRs) is real y a very es-sential starting point in the implementation of QFD, since it largely affects the target setting value of design requirements. This pa-per aims to propose a novel method to deal with the relative importance ratings (RIRs) of CRs problem considering customers’ diversified requirements and unknown information on customers’ weights, which is an indispensable process for determining the final importance ratings of CRs. First, a new concept of customer’s assessment structure is proposed according to the basic idea of grey relational analysis (GRA), and then a constrained nonlinear optimization model is constructed to describe the assessment information aggregation factors of CRs considering customers’ personalized and diversified requirements. Furthermore, an im-mune particle swarm optimization (IPSO) algorithm is designed to solve the model, and the weight vector of customers is obtained. Final y, a car door design example is introduced to il ustrate the novel hybrid GRA-IPSO method’s potential application in deter-mining the RIRs of CRs.

  4. Measurement of after-heat production and dose rates of spent AVR fuel elements

    Data on the afterheat production and dose rate of spent AVR fuel elements prepared by the ORIGEN computer program are verified by measurements. Individual measurements of afterheat and dose rate were implemented on 17 AVR fuel elements with decay periods of 150 days and more than four years, and burnups between 4.1 and 16.4% fima were implemented in the HOT CELLS at the Juelich Nuclear Research Centre. The radiation energy absorbed in the fuel elements and converted into heat was measured with a calorimeter, whereas the emitted radiation fraction was determined via dose rate measurements. The measured results for fuel elements with decay periods of more than one year are in good agreement with the data from ORIGEN. In the case of fuel elements with shorter decay periods (approx. 150 days) in part considerably lower values were measured which can be explained by the fact that the power gradient in time of the fuel elements in the reactor can vary considerably whereas mean are included in the ORIGEN computations assuming full-load operation. (orig./HP))

  5. Nocturnal Light Pulses Lower Carbon Dioxide Production Rate without Affecting Feed Intake in Geese.

    Huang, De-Jia; Yang, Shyi-Kuen

    2016-03-01

    This study was conducted to investigate the effect of nocturnal light pulses (NLPs) on the feed intake and metabolic rate in geese. Fourteen adult Chinese geese were penned individually, and randomly assigned to either the C (control) or NLP group. The C group was exposed to a 12L:12D photoperiod (12 h light and 12 h darkness per day), whereas the NLP group was exposed to a 12L:12D photoperiod inserted by 15-min lighting at 2-h intervals in the scotophase. The weight of the feed was automatically recorded at 1-min intervals for 1 wk. The fasting carbon dioxide production rate (CO2 PR) was recorded at 1-min intervals for 1 d. The results revealed that neither the daily feed intake nor the feed intakes during both the daytime and nighttime were affected by photoperiodic regimen, and the feed intake during the daytime did not differ from that during the nighttime. The photoperiodic treatment did not affect the time distribution of feed intake. However, NLPs lowered (p<0.05) the mean and minimal CO2 PR during both the daytime and nighttime. Both the mean and minimal CO2 PR during the daytime were significantly higher (p<0.05) than those during the nighttime. We concluded that NLPs lowered metabolic rate of the geese, but did not affect the feed intake; both the mean and minimal CO2 PR were higher during the daytime than during the nighttime. PMID:26950871

  6. Scaling in situ cosmogenic nuclide production rates using analytical approximations to atmospheric cosmic-ray fluxes

    Lifton, Nathaniel; Sato, Tatsuhiko; Dunai, Tibor J.

    2014-01-01

    Several models have been proposed for scaling in situ cosmogenic nuclide production rates from the relatively few sites where they have been measured to other sites of interest. Two main types of models are recognized: (1) those based on data from nuclear disintegrations in photographic emulsions combined with various neutron detectors, and (2) those based largely on neutron monitor data. However, stubborn discrepancies between these model types have led to frequent confusion when calculating surface exposure ages from production rates derived from the models. To help resolve these discrepancies and identify the sources of potential biases in each model, we have developed a new scaling model based on analytical approximations to modeled fluxes of the main atmospheric cosmic-ray particles responsible for in situ cosmogenic nuclide production. Both the analytical formulations and the Monte Carlo model fluxes on which they are based agree well with measured atmospheric fluxes of neutrons, protons, and muons, indicating they can serve as a robust estimate of the atmospheric cosmic-ray flux based on first principles. We are also using updated records for quantifying temporal and spatial variability in geomagnetic and solar modulation effects on the fluxes. A key advantage of this new model (herein termed LSD) over previous Monte Carlo models of cosmogenic nuclide production is that it allows for faster estimation of scaling factors based on time-varying geomagnetic and solar inputs. Comparing scaling predictions derived from the LSD model with those of previously published models suggest potential sources of bias in the latter can be largely attributed to two factors: different energy responses of the secondary neutron detectors used in developing the models, and different geomagnetic parameterizations. Given that the LSD model generates flux spectra for each cosmic-ray particle of interest, it is also relatively straightforward to generate nuclide-specific scaling

  7. Reservoir characterization based on tracer response and rank analysis of production and injection rates

    Refunjol, B.T. [Lagoven, S.A., Pdvsa (Venezuela); Lake, L.W. [Univ. of Texas, Austin, TX (United States)

    1997-08-01

    Quantification of the spatial distribution of properties is important for many reservoir-engineering applications. But, before applying any reservoir-characterization technique, the type of problem to be tackled and the information available should be analyzed. This is important because difficulties arise in reservoirs where production records are the only information for analysis. This paper presents the results of a practical technique to determine preferential flow trends in a reservoir. The technique is a combination of reservoir geology, tracer data, and Spearman rank correlation coefficient analysis. The Spearman analysis, in particular, will prove to be important because it appears to be insightful and uses injection/production data that are prevalent in circumstances where other data are nonexistent. The technique is applied to the North Buck Draw field, Campbell County, Wyoming. This work provides guidelines to assess information about reservoir continuity in interwell regions from widely available measurements of production and injection rates at existing wells. The information gained from the application of this technique can contribute to both the daily reservoir management and the future design, control, and interpretation of subsequent projects in the reservoir, without the need for additional data.

  8. Determination of Rate and Causes of Wastage of Blood and Blood Products in Iranian Hospitals

    Rafat Mohebbi Far

    2014-06-01

    Full Text Available OBJECTIVE: The purpose of this study was to determine the rate and causes of wastage of blood and blood products (packed red cells, plasma, platelets, and cryoprecipitate in Qazvin hospitals. METHODS: The study was conducted in all hospitals in Qazvin, including 5 teaching hospitals, 2 social welfare hospitals, 3 private hospitals, 1 charity hospital, and 1 military hospital. This descriptive study was based on available data from hospital blood banks in the province of Qazvin. The research instrument was a 2-part questionnaire. The first part was related to demographic characteristics of hospitals and the second part elicited information about blood and blood component wastage. The collected data were then analyzed using descriptive statistic methods and SPSS 11.5. RESULTS: Blood wastage may occur for a number of reasons, including time expiry, wasted imports, blood medically or surgically ordered but not used, stock time expired, hemolysis, or miscellaneous reasons. Data indicated that approximately 77.9% of wasted pack cell units were wasted for the reason of time expiry. Pack cell wastage in hospitals is reported to range from 1.93% to 30.7%. Wastage at all hospitals averaged 9.8% among 30.913 issued blood products. Overall blood and blood product (packed red cells, plasma, platelets, and cryoprecipitate wastage was 3048 units and average total wastage per participant hospital for all blood groups was 254 units per year. CONCLUSION: Blood transfusion is an essential part of patient care. The blood transfusion system has made significant advancements in areas such as donor management, storage of blood, cross-matching, rational use of blood, and distribution. In order to improve the standards of blood banks and the blood transfusion services in Iran, comprehensive standards have been formulated to ensure better quality control in collection, storage, testing, and distribution of blood and its components for the identified major factors

  9. Combined results on b-hadron production rates and decay properties

    Abbaneo, D; Andreev, V; Barberio, E; Battaglia, Marco; Blyth, S; Boix, G; Calvi, M; Checchia, P; Coyle, P; Di Ciaccio, Lucia; Gagnon, P; Hawkings, R; Hayes, O J; Henrard, P; Hessing, T L; Kroll, I J; Leroy, O; Lucchesi, D; Margoni, M; Mele, S; Moser, H G; Muheim, F; Palla, Fabrizio; Pallin, D; Parodi, F; Paulini, M; Piotto, E; Privitera, P; Rosnet, P; Roudeau, Patrick; Rousseau, D; Schneider, O; Shepherd-Themistocleous, C H; Simonetto, F; Spagnolo, P; Stocchi, A; Su, D; Usher, T; Weiser, C; Wicklund, B; Willocq, S; CERN. Geneva

    2001-01-01

    Combined results on b-hadron lifetimes, b-hadron production rates, B^0_d - \\bar{B^0_d} and B^0_S - \\bar{B^0_s} oscillations, the decay width difference between the mass eigenstates of the B^0_s - \\bar{B^0_s} system, the average number of c and \\bar{c} quarks in b-hadron decays, and searches for CP violation in the B^0_d - \\bar{B-0_d} system are presented. They have been obtained from published and preliminary measurements available in Summer 2000 from the ALEPH, CDF, DELPHI, L3, OPAL and SLD Collaborations. These results have been used to determine the parameters of the CKM unitarity triangle.

  10. Relative rates of nitric oxide and nitrous oxide production by nitrifiers, denitrifiers, and nitrate respirers

    Anderson, I. C.; Levine, J. S.

    1986-01-01

    An account is given of the atmospheric chemical and photochemical effects of biogenic nitric and nitrous oxide emissions. The magnitude of the biogenic emission of NO is noted to remain uncertain. Possible soil sources of NO and N2O encompass nitrification by autotropic and heterotropic nitrifiers, denitrification by nitrifiers and denitrifiers, nitrate respiration by fermenters, and chemodenitrification. Oxygen availability is the primary determinant of these organisms' relative rates of activity. The characteristics of this major influence are presently investigated in light of the effect of oxygen partial pressure on NO and N2O production by a wide variety of common soil-nitrifying, denitrifying, and nitrate-respiring bacteria under laboratory conditions. The results obtained indicate that aerobic soils are primary sources only when there is sufficient moisture to furnish anaerobic microsites for denitrification.

  11. Measurement of tritium production rate distribution for a fusion-fission hybrid conceptual reactor

    A fusion-fission hybrid conceptual reactor is established. It consists of a DT neutron source and a spherical shell of depleted uranium and hydrogen lithium. The tritium production rate (TPR) distribution in the conceptual reactor was measured by DT neutrons using two sets of lithium glass detectors with different thicknesses in the hole in the vertical direction with respect to the D+ beam of the Cockcroft-Walton neutron generator in direct current mode. The measured TPR distribution is compared with the calculated results obtained by the three-dimensional Monte Carlo code MCNP5 and the ENDF/B-Ⅵ data file. The discrepancy between the measured and calculated values can be attributed to the neutron data library of the hydrogen lithium lack S(α, β) thermal scattering model, so we show that a special database of low-energy and thermal neutrons should be established in the physics design of fusion-fission hybrid reactors. (authors)

  12. Hydrogen production rates from ground-based Fabry-Perot observations of comet Kohoutek

    Scherb, F.

    1981-01-01

    The only ground-based observations of a cometary hydrogen corona that have been obtained up to the present were carried out during the appearance of comet Kohoutek (1973 XII). Hydrogen Balmer alpha (H-alpha) emission from the gas cloud surrounding the comet was detected using a Fabry-Perot spectrometer at Kitt Peak National Observatory. These observations have been reexamined using (1) recently obtained solar full-disk Lyman beta emission line profiles, (2) a new calibration of the absolute sensitivity of the Fabry-Perot spectrometer based on comparison of NGC 7000 with standard stars and the planetary nebula NGC 7662, and (3) corrections for atmospheric extinction instead of the geocoronal H-alpha comparison method used previously to obtain comet H-alpha intensities. The new values for hydrogen production rates are in good agreement with results obtained from Lyman alpha observations of comet Kohoutek.

  13. Microalgae from domestic wastewater facility's high rate algal pond: Lipids extraction, characterization and biodiesel production.

    Drira, Neila; Piras, Alessandra; Rosa, Antonella; Porcedda, Silvia; Dhaouadi, Hatem

    2016-04-01

    In this study, the harvesting of a biomass from a high rate algal pond (HRAP) of a real-scale domestic wastewater treatment facility and its potential as a biomaterial for the production of biodiesel were investigated. Increasing the medium pH to 12 induced high flocculation efficiency of up to 96% of the biomass through both sweep flocculation and charge neutralization. Lipids extracted by ultrasounds from this biomass contained around 70% of fatty acids, with palmitic and stearic acids being the most abundant. The extract obtained by supercritical CO2 contained 86% of fatty acids. Both conventional solvents extracts contained only around 10% of unsaturated fats, whereas supercritical CO2 extract contained more than 40% of unsaturated fatty acids. This same biomass was also subject to direct extractive-transesterification in a microwave reactor to produce fatty acid methyl esters, also known as, raw biodiesel. PMID:26866759

  14. Entropy Production Rate of a One-Dimensional Alpha-Fractional Diffusion Process

    Yuri Luchko

    2016-02-01

    Full Text Available In this paper, the one-dimensional α-fractional diffusion equation is revisited. This equation is a particular case of the time- and space-fractional diffusion equation with the quotient of the orders of the time- and space-fractional derivatives equal to one-half. First, some integral representations of its fundamental solution including the Mellin-Barnes integral representation are derived. Then a series representation and asymptotics of the fundamental solution are discussed. The fundamental solution is interpreted as a probability density function and its entropy in the Shannon sense is calculated. The entropy production rate of the stochastic process governed by the α-fractional diffusion equation is shown to be equal to one of the conventional diffusion equation.

  15. Measurement of the production rates of η and η‧ in hadronic Z decays

    Buskulic, D.; Decamp, D.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Mours, B.; Alemany, R.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Gaitan, V.; Garrido, Ll.; Pacheco, A.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, S.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Gao, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Lou, J.; Qiao, C.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhao, W.; Atwood, W. B.; Bauerdick, L. A. T.; Blucher, E.; Bonvicini, G.; Bossi, F.; Boudreau, J.; Burnett, T. H.; Drevermann, H.; Forty, R. W.; Hagelberg, R.; Harvey, J.; Haywood, S.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lançon, E.; Lehraus, I.; Lohse, T.; Lusiani, A.; Martinez, M.; Mato, P.; Mattison, T.; Meinhard, H.; Menary, S.; Meyer, T.; Minten, A.; Miguel, R.; Moser, H.-G.; Nash, J.; Palazzi, P.; Perlas, J. A.; Ranjard, F.; Redlinger, G.; Rolandi, L.; Roth, A.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; Bencheikh, A. M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Pietrzyk, B.; Proriol, J.; Prulhière, F.; Stimpfl, G.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Efthymiopoulos, I.; Kyriakis, A.; Simopoulou, E.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Fouque, G.; Gamess, A.; Orteu, S.; Rosowsky, A.; Rougé, A.; Rumpf, M.; Tanaka, R.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Wasserbaech, S.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Altoon, B.; Boyle, O.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Scarr, J. M.; Smith, K.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geiges, R.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Patton, S. J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Tomalin, I. R.; Wright, A. G.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Barczewski, T.; Kleinknecht, K.; Raab, J.; Renk, B.; Roehn, S.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wolf, B.; Aubert, J.-J.; Benchouk, C.; Bernard, V.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Papalexiou, S.; Payre, P.; Qian, Z.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Bauer, C.; Blum, W.; Brown, D.; Cowan, G.; Dehning, B.; Dietl, H.; Dydak, F.; Fernandez-Bosman, M.; Frank, M.; Halley, A. W.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; St. Denis, R.; Takashima, M.; Thomas, J.; Wolf, G.; Bertin, V.; Boucrot, J.; Callot, O.; Chen, X.; Cordier, A.; Davier, M.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Zomer, F.; Abbaneo, D.; Amendolia, S. R.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Carpinelli, M.; Ciocci, M. A.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Giassi, A.; Giorgi, M. A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Carter, J. M.; Green, M. G.; March, P. V.; Mir, Ll. M.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; West, L. R.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Kozanecki, W.; Lemaire, M. C.; Locci, E.; Loucatos, S.; Monnier, E.; Perez, P.; Perrier, F.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Ashman, J. G.; Babbage, W.; Booth, C. N.; Buttar, C.; Carney, R. E.; Cartwright, S.; Combley, F.; Hatfield, F.; Reeves, P.; Thompson, L. F.; Barberio, E.; Brandt, S.; Grupen, C.; Mirabito, L.; Schäfer, U.; Ganis, G.; Giannini, G.; Gobbo, B.; Ragusa, F.; Bellantoni, L.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jared, R. C.; Leclaire, B. W.; Lishka, C.; Pan, Y. B.; Pater, J. R.; Pusztaszeri, J.-F.; Saadi, Y.; Sharma, V.; Schmitt, M.; Shi, Z. H.; Walsh, A. M.; Weber, F. V.; Whitney, M. H.; Wu, Sau Lan; Wu, X.; Zobernig, G.; Aleph Collaboration

    1992-10-01

    The decays η → γγ and η‧ → ηπ+π- have been observed in hadronic decays of the Z produced at LEP. The fragmentation functions of both the η and η‧ have been measured. The measured multiplicities for x > 0.1 are 0.298±0.023±0.021 and 0.068±0.016 for η and η‧ respectively. While the fragmentation function for the η is fairly well described by the JETSET Monte Carlo, it is found that the production rate of the η‧ is a factor of four less than the corresponding prediction.

  16. Measurement of tritium production rate distribution for a fusion-fission hybrid conceptual reactor

    WANG Xin-Hua; GUO Hai-Ping; MOU Yun-Feng; ZHENG Pu; LIU Rong; YANG Xiao-Fei; YANG Jian

    2013-01-01

    A fusion-fission hybrid conceptual reactor is established.It consists of a DT neutron source and a spherical shell of depleted uranium and hydrogen lithium.The tritium production rate (TPR) distribution in the conceptual reactor was measured by DT neutrons using two sets of lithium glass detectors with different thicknesses in the hole in the vertical direction with respect to the D+ beam of the Cockcroft-Walton neutron generator in direct current mode.The measured TPR distribution is compared with the calculated results obtained by the threedimensional Monte Carlo code MCNP5 and the ENDF/B-Ⅵ data file.The discrepancy between the measured and calculated values can be attributed to the neutron data library of the hydrogen lithium lack S(α,β) thermal scattering model,so we show that a special database of low-energy and thermal neutrons should be established in the physics design of fusion-fission hybrid reactors.

  17. Speech sound acquisition, coarticulation, and rate effects in a neural network model of speech production.

    Guenther, F H

    1995-07-01

    This article describes a neural network model of speech motor skill acquisition and speech production that explains a wide range of data on variability, motor equivalence, coarticulation, and rate effects. Model parameters are learned during a babbling phase. To explain how infants learn language-specific variability limits, speech sound targets take the form of convex regions, rather than points, in orosensory coordinates. Reducing target size for better accuracy during slower speech leads to differential effects for vowels and consonants, as seen in experiments previously used as evidence for separate control processes for the 2 sound types. Anticipatory coarticulation arises when targets are reduced in size on the basis of context; this generalizes the well-known look-ahead model of coarticulation. Computer simulations verify the model's properties. PMID:7624456

  18. Simulation of corrosion product activity in extended operating cycles of PWRs under flow rate transient and nonlinearly rising corrosion rates coupled with pH effects

    Highlights: ► The CPA is studied for PWRs under flow rate transients and extended cycles. ► Simulations were done for extended cycles with pH-level and boric acid variations. ► For a flow rate transient in the first cycle, the saturation value of CPA goes up. ► During second cycle, the CPA peak value becomes 13% higher. - Abstract: Corrosion product activity (CPA) has been studied in a typical pressurized water reactor (PWR) under flow rate transients, having extended burn-up cycles with time dependent pH-level and boric acid variations. The simulations show CPA buildup towards saturation following the mixing of boron in primary coolant and a decreasing trend following the increase in pH value. In the presence of boric acid and pH control, the nonlinearly rising corrosion rates result in enhanced saturation levels when compared with the constant corrosion rate case. The behavior of CPA has been compared in multiple cycles for both no flow rate transient case and a transient with enriched boric acid (40%) in coolant. In first cycle when flow rate transient is applied the saturation value goes up and during second cycle, the peak value for the flow rate transient case becomes about 13% higher when compared with no flow rate transient scenario. The saturation CPA value in second cycle for transient case is also 14% higher when compared to saturation value for no transient case in the same cycle. However, in subsequent cycles the effect of flow rate transient from first cycle on CPA gets diminished. When only flow rate is allowed to change and power is kept constant a pronounced rise in saturation value of CPA occurs. However, in the case of power-following flow rate transient, only small rise in the saturation values is observed.

  19. Greater carbon stocks and faster turnover rates with increasing agricultural productivity

    Sanderman, J.; Fallon, S.; Baisden, T. W.

    2013-12-01

    H.H. Janzen (2006) eloquently argued that from an agricultural perspective there is a tradeoff between storing carbon as soil organic matter (SOM) and the soil nutrient and energy benefit provided during SOM mineralization. Here we report on results from the Permanent Rotation Trial at the Waite Agricultural Institute, South Australia, indicating that shifting to an agricultural management strategy which returns more carbon to the soil, not only leads to greater carbon stocks but also increases the rate of carbon cycling through the soil. The Permanent Rotation Trial was established on a red Chromosol in 1925 with upgrades made to several treatments in 1948. Decadal soil samples were collected starting in 1963 at two depths, 0-10 and 10-22.5 cm, by compositing 20 soil cores taken along the length of each plot. We have chosen to analyze five trials representing a gradient in productivity: permanent pasture (Pa), wheat-pasture rotation (2W4Pa), continuous wheat (WW), wheat-oats-fallow rotation (WOF) and wheat-fallow (WF). For each of the soil samples (40 in total), the radiocarbon activity in the bulk soil as well as size-fractionated samples was measured by accelerator mass spectrometry at ANU's Radiocarbon Dating Laboratory (Fallon et al. 2010). After nearly 70 years under each rotation, SOC stocks increased linearly with productivity data across the trials from 24 to 58 tC ha-1. Importantly, these differences were due to greater losses over time in the low productivity trials rather than gains in SOC in any of the trials. Uptake of the bomb-spike in atmospheric 14C into the soil was greatest in the trials with the greatest productivity. The coarse size fraction always had greater Δ14C values than the bulk soil samples. Several different multi-pool steady state and non-steady state models were used to interpret the Δ14C data in terms of SOC turnover rates. Regardless of model choice, either the decay rates of all pools needed to increase or the allocation of C to

  20. EMPIRICAL ASSESSMENT OF THE GROWTH RATE OF MAIZE PRODUCTION IN THE PRE - SAP, SAP AND POST - SAP PERIODS IN NIGERIA

    Oyinbo Oyakhilomen

    2012-05-01

    Full Text Available This study was carried out to provide empirical evidence on the growth rates of maize production in three sub - periods in Nigeria namely pre - Structural Adjustment Programme period, Structural Adjustment Program period and post - Structural Adjustment Programme period. Secondary data on maize production in Nigeria during the Pre - Structural Adjustment Programme period (1970 to 1985, Structural Adjustment period (1986 to 1994 and post - Structural Adjustment Programme period (1995 to 2007 were employed in this study. A growth rate model was used to estimate the growth rates of maize in the three sub - periods. The results of the analysis showed that the instantaneous growth rates of maize production are - 0.1%, 5.7% and 2.4% and the compound rates of growth of maize production are - 0.001%, 0.059% and 0.024% for the pre - Structural Adjustment Programme, Structural Adjustment Programme and post - Structural Adjustment Programme periods respectively. The higher compound growth rate of maize production in the Structural Adjustment Programme period implies that the policy reforms in the period was more effective in ensuring increased growth of maize production over that of other periods in Nigeria. Therefore, despite the myriads of problems associated with the programme in Nigeria, it was beneficial to maize production in Nigeria.

  1. Influence of pH and temperature on alunite dissolution rates and products

    Acero, Patricia; Hudson-Edwards, Karen

    2015-04-01

    Aluminium is one of the main elements in most mining-affected environments, where it may influence the mobility of other elements and play a key role on pH buffering. Moreover, high concentrations of Al can have severe effects on ecosystems and humans; Al intake, for example, has been implicated in neurological pathologies (e.g., Alzheimer's disease; Flaten, 2001). The behaviour of Al in mining-affected environments is commonly determined, at least partially, by the dissolution of Al sulphate minerals and particularly by the dissolution of alunite (KAl3(SO4)2(OH)6), which is one of the most important and ubiquitous Al sulphates in mining-affected environments (Nordstrom, 2011). The presence of alunite has been described in other acid sulphate environments, including some soils (Prietzel & Hirsch, 1998) and on the surface of Mars (Swayze et al., 2008). Despite the important role of alunite, its dissolution rates and products, and their controlling factors under conditions similar to those found in these environments, remain largely unknown. In this work, batch dissolution experiments have been carried out in order to shed light on the rates, products and controlling factors of alunite dissolution under different pH conditions (between 3 and 8) and temperatures (between 279 and 313K) similar to those encountered in natural systems. The obtained initial dissolution rates using synthetic alunite, based on the evolution of K concentrations, are between 10-9.7 and 10-10.9 mol-m-2-s-1, with the lowest rates obtained at around pH 4.8, and increases in the rates recorded with both increases and decreases in pH. Increases of temperature in the studied range also cause increases in the dissolution rates. The dissolution of alunite dissolution is incongruent, as has been reported for jarosite (isostructural with alunite) by Welch et al. (2008). Compared with the stoichiometric ratio in the bulk alunite (Al/K=3), K tends to be released to the solution preferentially over Al

  2. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere

    Bouvier-Brown, N. C.; Goldstein, A. H.; Worton, D. R.; Matross, D. M.; Gilman, J. B.; Kuster, W. C.; Welsh-Bon, D.; Warneke, C.; de Gouw, J. A.; Cahill, T. M.; Holzinger, R.

    2009-03-01

    We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments - a gas chromatograph with mass spectrometer detector (GC-MS), a proton transfer reaction mass spectrometer (PTR-MS), and a thermal desorption aerosol GC-MS (TAG) - and found to be abundant within and above Blodgett Forest. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO), a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4-68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72-10.2 μgCg-1 h-1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde) in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models.

  3. Right-handed neutrino production rate at T>160 GeV

    The production rate of right-handed neutrinos from a Standard Model plasma at a temperature above a hundred GeV has previously been evaluated up to NLO in Standard Model couplings (g∼2/3) in relativistic (M∼πT) and non-relativistic regimes (M≫πT), and up to LO in an ultrarelativistic regime (M≲gT). The last result necessitates an all-orders resummation of the loop expansion, accounting for multiple soft scatterings of the nearly light-like particles participating in 1↔2 reactions. In this paper we suggest how the regimes can be interpolated into a result applicable for any right-handed neutrino mass and at all temperatures above 160 GeV. The results can also be used for determining the lepton number washout rate in models containing right-handed neutrinos. Numerical results are given in a tabulated form permitting for their incorporation into leptogenesis codes. We note that due to effects from soft Higgs bosons there is a narrow intermediate regime around M∼g1/2T in which our interpolation is phenomenological and a more precise study would be welcome

  4. A study on Haemophilus influenzae type b growth rate and capsule production in different media

    Afshar, M.

    2012-06-01

    Full Text Available to compare growth rate and capsule production. Four liquid media namely brain heart infusion broth (BHI, trypticase soy broth (TSB, Mueller Hinton Broth (MHB and Gonococci broth (GC with added supplements (1% hemoglobin, 1% Isovitalex were used. The growth was measured by colony counting (CFU/ml using serial dilution. Four of the isolates showed the highest growth rate with the average of 1013 CFU/ml on BHI broth while TSB had the second highest growth of more than 1010 CFU/ml in an 18-hour culture at 37 ºC culture. In the next step, the amount of capsular polysaccharide (CPS-b antigen which is made of Polyribosyl ribitol phosphate (PRP was assessed all isolates by two methods: modified Indirect Sandwich Enzyme-linked immunosorbent assay (ELISA and Bial method to select the isolate producing the highest amount of PRP. The antisera used in sandwich ELISA were prepared by immunization of Rabbit and Rat. The maximal amount of PRP was produced by isolate Hib (5s with the amount of 321 mg/lit.

  5. The structure of some floral elements and the nectar production rate of Polemonium caeruleum L.

    Mirosława Chwil

    2012-12-01

    Full Text Available The present study, carried out in the period 2008 - 2009, covered some morphological and anatomical features of the flowers of Polemonium caeruleum L. and their nectar production rate in the climatic conditions of the Lublin region. Observations were made with stereoscopic, light and scanning electron microscopy. Nectar production in the flowers was determined using the pipette method. The flowers of Polemonium caeruleum develop a calyx covered by an epidermis with numerous non-glandular and glandular trichomes. The secretory trichomes are composed of a several-celled stalk and a four-celled head. At the boundary of the corolla tube and the lobes, there is white colouration with violet nectar guides. The epidermis in this region produces several-celled living trichomes that close the entry into the corolla tube, thereby protecting the nectar accumulated in it. These hairs are at the same time glistening colour attractants for insects. The tripartite stigma of the pistil is covered, from the adaxial side, by unicellular papillae with striated cuticular ornamentation, growing at high density. Around the ovary there is located a nectariferous disc, in the form of a free projection, which secrets nectar with sugar concentration of 29 - 52% and sugar weight ranging 1.1 - 1.8 mg/flower.

  6. Cryogenic Treatment of Production Components in High-Wear Rate Wells; FINAL

    Deep Cryogenic Tempering (DCT) is a specialized process whereby the molecular structure of a material is ''re-trained'' through cooling to -300 F and then heating to+175-1100 F. Cryocon, Inc. (hereafter referred to as Cryocon) and RMOTC entered an agreement to test the process on oilfield production components, including rod pumps, rods, couplings, and tubing. Three Shannon Formation wells were selected (TD about 500 ft) based on their proclivity for high component wear rates. Phase 1 of the test involved operation for a nominal 120 calendar day period with standard, non-treated components. In Phase 2, treated components were installed and operated for another nominal 120 calendar day period. Different cryogenic treatment profiles were used for components in each well. Rod pumps (two treated and one untreated) were not changed between test phases. One well was operated in pumped-off condition, resulting in abnormal wear and disqualification from the test. Testing shows that cryogenic treatment reduced wear of rods, couplers, and pump barrels. Testing of production tubing produced mixed results

  7. Estimating methane production rates in bogs and landfills by deuterium enrichment of pore water

    Siegel, D.I.; Chanton, J.P.; Glaser, P.H.; Chasar, L.S.; Rosenberry, D.O.

    2001-01-01

    Raised bogs and municipal waste landfills harbor large populations of methanogens within their domed deposits of anoxic organic matter. Although the methane emissions from these sites have been estimated by various methods, limited data exist on the activity of the methanogens at depth. We therefore analyzed the stable isotopic signature of the pore waters in two raised bogs from northern Minnesota to identify depth intervals in the peat profile where methanogenic metabolism occurs. Methanogenesis enriched the deuterium (2H) content of the deep peat pore waters by as much as +11% (Vienna Standard Mean Sea Water), which compares to a much greater enrichment factor of +70% in leachate from New York City's Fresh Kills landfill. The bog pore waters were isotopically dated by tritium (3H) to be about 35 years old at 1.5 m depth, whereas the landfill leachate was estimated as ~ 17 years old from Darcy flow calculations. According to an isotopic mass balance the observed deuterium enrichment indicates that about 1.2 g of CH4m-3 d-1 were produced within the deeper peat, compared to about 2.8 g CH4 m-3 d-1 in the landfill. The values for methane production in the bog peat are substantially higher than the flux rates measured at the surface of the bogs or at the landfill, indicating that deeper methane production may be much higher than was previously assumed.

  8. Systematic comparison of ISOLDE-SC yields with calculated in-target production rates

    Recently, a series of dedicated inverse-kinematics experiments performed at GSI, Darmstadt, has brought an important progress in our understanding of proton and heavy-ion induced reactions at relativistic energies. The nuclear reaction code ABRABLA that has been developed and benchmarked against the results of these experiments has been used to calculate nuclide production cross sections at different energies and with different targets and beams. These calculations are used to estimate nuclide production rates by protons in thick targets, taking into account the energy loss and the attenuation of the proton beam in the target, as well as the low-energy fission induced by the secondary neutrons. The results are compared to the yields of isotopes of various elements obtained from different targets at CERN-ISOLDE with 600 MeV protons, and the overall extraction efficiencies are deduced. The dependence of these extraction efficiencies on the nuclide half-life is found to follow a simple pattern in many different cases. A simple function is proposed to parameterize this behavior in a way that quantifies the essential properties of the extraction efficiency for the element and the target - ion-source system in question. (orig.)

  9. High flow rate nozzle system with production of uniform size droplets

    Stockel, Ivar H.

    1990-01-01

    Method steps for production of substantially uniform size droplets from a flow of liquid include forming the flow of liquid, periodically modulating the momentum of the flow of liquid in the flow direction at controlled frequency, generating a cross flow direction component of momentum and modulation of the cross flow momentum of liquid at substantially the same frequency and phase as the modulation of flow direction momentum, and spraying the so formed modulated flow through a first nozzle outlet to form a desired spray configuration. A second modulated flow through a second nozzle outlet is formed according to the same steps, and the first and second modulated flows impinge upon each other generating a liquid sheet. Nozzle apparatus for modulating each flow includes rotating valving plates interposed in the annular flow of liquid. The plates are formed with radial slots. Rotation of the rotating plates is separably controlled at differential angular velocities for a selected modulating frequency to achieve the target droplet size and production rate for a given flow. The counter rotating plates are spaced to achieve a desired amplitude of modulation in the flow direction, and the angular velocity of the downstream rotating plate is controlled to achieve the desired amplitude of modulation of momentum in the cross flow direction. Amplitude of modulation is set according to liquid viscosity.

  10. Rapid Production of Bose-Einstein Condensates at a 1 Hz Rate

    Farkas, Daniel; Ramirez-Serrano, Jaime; Salim, Evan

    2013-05-01

    The speed at which Bose-Einstein condensates (BECs) can be produced is a key metric for the performance of ultracold-atom inertial sensors, gravimeters, and magnetometers, where production cycle time of ultracold atoms determines sensor bandwidth. Here, we demonstrate production of 87Rb BECs at rates exceeding 1 Hz. Not only can we create a BEC from a hot vapor in less than one second, but we can continuously repeat the process for several cycles. Such speeds are possible because of the short evaporation times that result when atoms are confined in tight traps. In our case, we magnetically trap atoms with an atom chip that seals the top of one of ColdQuanta's RuBECi®vacuum cells. With RF evaporative cooling sequences as short as 450 ms, we attain nearly pure condensates of 2 × 104 atoms. In the future, the apparatus described here will be integrated into a portable system that houses all of the components needed to produce BECs (e.g. lasers, vacuum, electronics, imaging, etc.) in a volume less than 0.3 m3. This work was supported by the Office of Naval Research (SBIR contract N00014-10-C-0282).

  11. Analytical Study of Pair Production Rate from Vacuum in an Elliptic Polarized Field by a Two-Level Transition Technique

    Electron-positron pair production rate created from vacuum in the presence of an elliptically polarized laser field is investigated. By applying the technique of two level transition amplitude, a routine for obtaining pair production rate is presented, and approximate analytical expressions are given both for the low frequency strong field regime and the high frequency weak field regime. We found that for an elliptically polarized field, the electron-positron pair production rate decrease when the elliptic eccentricity increase in the high frequency weak field regime, however, in the low frequency strong field regime, there is almost the same electron-positron pair production rate as in the constant electric field case. (physics of elementary particles and fields)

  12. Dietary Arginine Requirements for Growth Are Dependent on the Rate of Citrulline Production in Mice123

    Marini, Juan C; Agarwal, Umang; Didelija, Inka C

    2015-01-01

    Background: In many species, including humans, arginine is considered a semiessential amino acid because under certain conditions endogenous synthesis cannot meet its demand. The requirements of arginine for growth in mice are ill defined and seem to vary depending on the genetic background of the mice. Objective: The objective of this study was to determine the metabolic and molecular basis for the requirement of arginine in 2 mouse strains. Methods: Institute of Cancer Research (ICR) and C57BL/6 (BL6) male mice were fed arginine-free or arginine-sufficient diets (Expt. 1) or 1 of 7 diets with increasing arginine concentration (from 0- to 8-g/kg diet, Expt. 2) between day 24 and 42 of life to determine the arginine requirements for growth. Citrulline production and “de novo” arginine synthesis were measured with use of stable isotopes, and arginine requirements were determined by breakpoint analysis and enzyme expression by reverse transcriptase-polymerase chain reaction. Results: In Expt. 1, ICR mice grew at the same rate regardless of the arginine concentration of the diet (mean ± SE: 0.66 ± 0.04 g/d, P = 0.80), but BL6 mice had a reduced growth rate when fed the arginine-free diet (0.25 ± 0.02 g/d, P < 0.001) compared to the 8-g arginine/kg diet (0.46 ± 0.03 g/d). ICR mice showed at least a 2-fold greater expression (P < 0.001) of ornithine transcarbamylase (OTC) than BL6 mice, which translated into a greater rate of citrulline (25%) and arginine synthesis (49%, P < 0.002). In Expt. 2, breakpoint analysis showed that the requirement for growth of BL6 mice was met with 2.32 ± 0.39 g arginine/kg diet; for ICR mice, however, no breakpoint was found. Conclusion: Our data indicate that a reduced expression of OTC in BL6 mice translates into a reduced production of citrulline and arginine compared with ICR mice, which results in a dietary arginine requirement for growth in BL6 mice, but not in ICR mice. PMID:25855119

  13. HE CONVERSION OF THE EFFICIENCY OF LABOR, RESPECTIVELY OF LABOR PRODUCTIVITY IN THE ECONOMIC AND COMMERCIAL RATE OF RETURN

    Constantin CĂRUNTU

    2010-12-01

    Full Text Available Generally, an activity is considered to be efficient if the production implies low costs or if the revenues from selling the products on the market outweigh the expenditures that were made to achieve them. Labor productivity as an efficiency indicator of a production process represents an expression of the relationship between effect (products, services and effort (work means, labor force, work items. Through the labor productivity conversion in rates of return (economic and commercial is determined an evolution and an influence on these rates, driving the company’s own efforts to innovate, produce and harness goods, works and services with maximum utility, efficiency and competitiveness services. The aim of this paper is to highlight the work efficiency, respectively the labor productivity detached from the factorial context in the trade and economic rates of return. The introduction presents some general aspects referring to labor productivity, then it will be presented and discussed the analytical methods used in the process of reflecting the labor productivity in the rates of return, the results analysis, and at the end of this paper it will be presented some conclusions based on the study case. The expected results consist in identifying the mechanisms by which labor efficiency is converted into the company’s economic and financial performance.

  14. Direct measurement of ozone production rates in Houston in 2009 and comparison with two estimation methods

    M. Cazorla

    2012-01-01

    Full Text Available Net ozone production rates, P(O3, were measured directly using the Penn State Measurement of Ozone Production Sensor (MOPS during the Study of Houston Atmospheric Radical Precursors (SHARP, 2009. Measured P(O3 peaked in the late morning, with values between 15 ppbv h−1 and 100 ppbv h−1, although values of 40–80 ppbv h−1 were typical for higher ozone days. These measurements were compared against ozone production rates calculated using measurements of hydroperoxyl (HO2, hydroxyl (OH, and nitric oxide (NO radicals, called "calculated P(O3". The same comparison was done using modeled radicals obtained from a box model with the RACM2 mechanism, called "modeled P(O3". Measured and calculated P(O3 had similar peak values but the calculated P(O3 tended to peak earlier in the morning when NO values were higher. Measured and modeled P(O3 had a similar dependence on NO, but the modeled P(O3 was only half the measured P(O3. The modeled P(O3 is less than the calculated P(O3 because the modeled HO2 is less than the measured HO2. While statistical analyses are not conclusive regarding the comparison between MOPS measurements and the two estimation methods, the calculated P(O3 with measured HO2 produces peak values similar to the measured P(O3 when ozone is high. Although the MOPS is new and more testing is required to verify its observations, the measurements in the SHARP field campaign show the potential of this new technique for contributing to the understanding of ozone-producing chemistry and to the monitoring of ozone's response to future air quality regulatory actions.

  15. Econometric Analysis of the Nexus of Exchange Rate Deregulation and Agricultural Share of Gross Domestic Product in Nigeria

    O. Oyinbo; Rekwot, G. Z.

    2014-01-01

    This study examined the relationship between exchange rate deregulation and the agricultural share of gross domestic product in Nigeria from an econometric perspective using time series data. The data were analysed using augmented dickey fuller unit root test, unrestricted vector autoregression and pairwise granger causality. The results of the data analysis revealed the existence of unidirectional causality from exchange rate to agricultural share of gross domestic production in Nigeria and ...

  16. Study of Biogas Production Rate from Water Hyacinth by Hydrothermal Pretreatment with Buffalo Dung as a Starter

    Teguh Kurniawan; Yuhelsa Putra; Dewi Murni

    2014-01-01

    In this paper we report the effects of hydrothermal pretreatment on biogas enhancement production rates from water hyacinth mixed with buffalo dung. The focus of the experiment was on the time of hydrothermal pretreatment and the ratio of water hyacinth with buffalo dung. The hydrothermal pretreated substrates were characterized by TDS, BOD and pH. The hydrothermal pretreatment of 60 minutes with the ratio of water hyacinth to buffalo dung 1:2 showed the highest biogas production rate at 7889...

  17. Determination of proton-induced production cross sections and production rates of {sup 129}I from Te

    Schnabel, C.; Lopez-Guitierrez, J.M.; Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Gloris, M.; Leya, I.; Michel, R. [Hannover Univ. (Germany); Herpers, U. [Koeln Univ. (Germany)

    1997-09-01

    In order to model the production of {sup 129}I in meteoroids, proton-induced production cross sections in the medium range of {sup 129}I from Te as well as production from meteoroid simulation experiments have been determined. {sup 129}I is a very important cosmogenic nuclide to study the constancy of cosmic radiation on long time scales. (author) 2 figs., 2 refs.

  18. Large production rate of new $B^0_s \\pi^{\\pm}$ and $D_s \\pi^{\\pm}$ states in high energy multi-production process

    Jin, Yi

    2016-01-01

    The production rate of the X(5568) observed by D0 collabotation is quite large and can not be understood by various general hadronization mechanism. We propose an inclusive resonance production formulation to calculate the cross section and extract the value of the effective wave function at origin. Based on these results we suspect X($D_s \\pi^{\\pm}$) can be copiously produced and observable at high enenrgy scatterings (the relative production ratio to D_s is larger than 10 %).

  19. Viral abundance, production, decay rates and life strategies (lysogeny versus lysis) in Lake Bourget (France).

    Thomas, Rozenn; Berdjeb, Lyria; Sime-Ngando, Télesphore; Jacquet, Stéphan

    2011-03-01

    We have investigated the ecology of viruses in Lake Bourget (France) from January to August 2008. Data were analysed for viral and bacterial abundance and production, viral decay, frequency of lysogenic cells, the contribution of bacteriophages to prokaryotic mortality and their potential influence on nutrient dynamics. Analyses and experiments were conducted on samples from the epilimnion (2 m) and the hypolimnion (50 m), taken at the reference site of the lake. The abundance of virus-like particles (VLP) varied from 3.4 × 10⁷to 8.2 × 10⁷ VLP ml⁻¹; with the highest numbers and virus-to-bacterium ratio (VBR = 69) recorded in winter. Viral production varied from 3.2 × 10⁴ VLP ml⁻¹  h⁻¹ (July) to 2 × 10⁶ VLP ml⁻¹ h⁻¹ (February and April), and production was lower in the hypolimnion. Viral decay rate reached 0.12-0.15 day⁻¹, and this parameter varied greatly with sampling date and methodology (i.e. KCN versus filtration). Using transmission electron microscopy (TEM) analysis, viral lysis was responsible for 0% (January) to 71% (February) of bacterial mortality, while viral lysis varied between 0% (April) and 53% (January) per day when using a modified dilution approach. Calculated from viral production and burst size, the virus-induced bacterial mortality varied between 0% (January) and 68% (August). A weak relationship was found between the two first methods (TEM versus dilution approach). Interestingly, flow cytometry analysis performed on the dilution experiment samples revealed that the viral impact was mostly on high DNA content bacterial cells whereas grazing, varying between 8.3% (June) and 75.4% (April), was reflected in both HDNA and LDNA cells equally. The lysogenic fraction varied between 0% (spring/summer) and 62% (winter) of total bacterial abundance, and increased slightly with increasing amounts of mitomycin C added. High percentages of lysogenic cells were recorded when bacterial abundance and activity were the lowest

  20. Elemental weathering fluxes and saprolite production rate in a Central African lateritic terrain (Nsimi, South Cameroon)

    Braun, Jean-Jacques; Marechal, Jean-Christophe; Riotte, Jean; Boeglin, Jean-Loup; Bedimo Bedimo, Jean-Pierre; Ndam Ngoupayou, Jules Remy; Nyeck, Brunot; Robain, Henri; Sekhar, M.; Audry, Stéphane; Viers, Jérôme

    2012-12-01

    are exported from the lateritic regolith and maybe due to the dissolution of kaolinite crystals. Compared to the other immobile elements (Zr, Hf, Nb and Th), Ti is significantly exported. Among redox-sensitive elements (Fe, V, Cr, Mn, Ce), only Ce and Mn are exported out of the hillside system. The other elements (Fe, V, Cr) are likely able to be mobilized but over a short distance only. Rb, Sr, Ba, Ni, Cu, Zn are affected by export processes. LREE and Y are exported but in very low amounts (in the range from μmol/ha/yr to mmol/ha/yr) while HREE and U are exported in negligible quantities. A first attempt is carried out to compare the mature ridge top profile from Nsimi SEW with the immature ridge top weathering profile from the Mule Hole SEW (South India), developed on similar granodioritic basement, in order to get deeper insight into (i) the contemporary saprolite production rates and (ii) the combined effect of precipitation (in terms of Mean Annual Rainfall, MAR) and evapotranspiration on the aggressiveness of the draining solutions. Considering (i) the contemporary Na flux as representative of the dissolution of plagioclase crystals and conservative during saprolitization processes and (ii) steady state of the inter-annual recharge (R) over a 10 years period, the current saprolite production rates (σr) are of 22 mm/kyr for Mule Hole SEW and 2 mm/kyr for Nsimi SEW, respectively. Even with a very low R/MAR ratio (0.04) compared to Nsimi, the chemical weathering at Mule Hole is active and related to the groundwater exports. At Mule Hole, plagioclase crystals are still present in the saprolite and the soil cover leading to a diffuse weathering front. The high Nsimi R/MAR ratio (0.2) allows the solution to be still aggressive with respect to the plagioclase and other weatherable minerals at the bedrock interface resulting in their complete breakdown in a few centimetres (sharp weathering front) leading to a mature saprolite. For the Nsimi SEW, if we consider (i

  1. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    Sreejith, K.M.; Krishna, K.S.

    production rate along the Walvis Ridge in the Atlantic Ocean. The present study suggests that variations in the Indian plate motion and frequent ridge jumps have a major role in controlling the magma production, particularly on long-period cycles (~16 Myr...

  2. Using cosmogenic isotopes to measure basin-scale rates of erosion

    The authors present a new and different approach to interpreting the abundance of in situ-produced cosmogenic nuclides such as 36Cl, 26Al, and 10Be. Unlike most existing models, which are appropriate for evaluating isotope concentrations on bedrock surfaces, this model can be used to interpret isotope concentration in fluvial sediment. Because sediment is a mixture of material derived from the entire drainage basin, measured isotope abundances can be used to estimate spatially-averaged rates of erosion and sediment transport. Their approach has the potential to provide geomorphologists with a relatively simple but powerful means by which to constrain rates of landscape evolution. The model considers the flux of cosmogenic isotopes into and out of various reservoirs. Implicit in model development are the assumptions that a geomorphic steady-state has been reached and that sampled sediment is spatially and temporally representative of all sediment leaving the basin. Each year, the impinging cosmic-ray flux produces a certain quantity of cosmogenic isotopes in the rock and soil of a drainage basin. For a basin in steady state, the outgoing isotope flux is also constant. They solve for the rate of mass loss as a function of isotope abundance in the sediment, the cosmic ray attenuation length, the isotope half life, and the effective isotope production rate. There are only a few published measurements of cosmogenic isotope abundance in sediment. They calculated model denudation rates for sediment samples from Zaire and central Texas. The denudation rates they calculated appear reasonable and are similar to those they have measured directly on granite landforms in Georgia and southeastern California and those calculated for the Appalachian Piedmont

  3. The Effects of Osmotic Potential on Ammonification, Immobilization, Nitrous Oxide Production, and Nitrification Rates in Penoyer Soil

    Low, Andrew P.

    1996-01-01

    An isotopic dilution method was used to test the effects of osmotic potential, (IJ' ,), upon nitrification, ammonification, N-immobilization, and nitrous oxide production rates in soil at solute concentrations encountered in Penoyer soil. A nitrification potential assay was also performed to approximate maximum nitrification rates. Nitrification potential rates in soil slurries exponentially declined in response to decreased osmotic potential. However, nitrification was independent of salt...

  4. Experimental tests for 36cl removal from aqueous solution

    This paper presents the experimental tests of a chlorine separation and purification method from aqueous samples with knowing content of Co, Cs, Eu, Ni and Sr stable elements. The method is based on the property of chloride ions to form a silver chloride white precipitate, followed by the use of the extraction chromatography on the strong anionic resin (Bio-Rad AG® 1-X4) to purify chlorine. The concentrations of Co, Cs, Eu, Ni and Sr (separated from Cl by using precipitation method) were measured by ICP-OES. The silver chloride precipitate was dissolved in 25 % NH3 solution and loaded onto the anionic resin. The chloride ions were strongly retained on the resin and eluted with a proper solution. The final solution, containing chloride ions, was converted to a form compatible with the spectrophotometric and Mohr titration techniques, which were used to determine chloride concentration. The separation yields of Co, Cs, Eu, Ni and Sr from Cl are very good. More than 98 % from the initial concentration of chlorine was recovered. (authors)

  5. Ion source memory in 36Cl accelerator mass spectrometry

    Since the DREAMS (Dresden Accelerator Mass Spectrometry) facility went operational in 2011, constant effort was put into enabling routine measurements of long-lived radionuclides as 10Be, 26Al and 41Ca. For precise AMS-measurements of the volatile element Cl the key issue is the minimization of the long term memory effect. For this purpose one of the two original HVE sources was mechanically modified, allowing the usage of bigger cathodes with individual target apertures. Additionally a more open geometry was used to improve the vacuum level. To evaluate this improvement in comparison to other up-to-date ion sources, a small inter-laboratory comparison had been initiated. The long-term memory effect in the Cs sputter ion sources of the AMS facilities VERA, ASTER and DREAMS had been investigated by running samples of natural 35Cl/37Cl-ratio and samples containing highly enriched 35Cl(35Cl/37Cl > 500). Primary goals of the research are the time constants of the recovery from the contaminated sample ratio to the initial ratio of the sample and the level of the long-term memory effect in the sources.

  6. Determination of 36Cl in nuclear waste from reactor decommissioning

    Hou, Xiaolin; Frøsig, Lars; Nielsen, Sven Poul

    2007-01-01

    An analytical method for the determination of Cl-36 in nuclear waste such as graphite, heavy concrete, steel, aluminum, and lead was developed. Several methods were investigated for decomposing the samples. AgCl precipitation was used to separate Cl-36 from the matrix elements, followed by ion...

  7. Resource Boom, Productivity Growth and Real Exchange Rate Dynamics - A dynamic general equilibrium analysis of South Africa

    Hildegunn E. Stokke

    2006-01-01

    We study the impact of a natural resource boom on structural change and real exchange rate dynamics, taking into account the indirect effect via relative sectoral productivity changes. Our contribution relative to the Dutch disease literature is threefold. First, the productivity specification is extended from simple learning by doing to include trade barriers and technology gap dynamics, consistent with the modern understanding of productivity growth. Second, we offer a dynamic general equil...

  8. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    Abdelhamid, M. [National Institute of Laser Enhanced Science, NILES, Cairo University, Giza (Egypt); Fortes, F.J.; Fernández-Bravo, A. [Department of Analytical Chemistry, Faculty of Sciences, University of Malaga, 29071 Malaga (Spain); Harith, M.A. [National Institute of Laser Enhanced Science, NILES, Cairo University, Giza (Egypt); Laserna, J.J., E-mail: laserna@uma.es [Department of Analytical Chemistry, Faculty of Sciences, University of Malaga, 29071 Malaga (Spain)

    2013-11-01

    Optical catapulting (OC) is a sampling and manipulation method that has been extensively studied in applications ranging from single cells in heterogeneous tissue samples to analysis of explosive residues in human fingerprints. Specifically, analysis of the catapulted material by means of laser-induced breakdown spectroscopy (LIBS) offers a promising approach for the inspection of solid particulate matter. In this work, we focus our attention in the experimental parameters to be optimized for a proper aerosol generation while increasing the particle density in the focal region sampled by LIBS. For this purpose we use shadowgraphy visualization as a diagnostic tool. Shadowgraphic images were acquired for studying the evolution and dynamics of solid aerosols produced by OC. Aluminum silicate particles (0.2–8 μm) were ejected from the substrate using a Q-switched Nd:YAG laser at 1064 nm, while time-resolved images recorded the propagation of the generated aerosol. For LIBS analysis and shadowgraphy visualization, a Q-switched Nd:YAG laser at 1064 nm and 532 nm was employed, respectively. Several parameters such as the time delay between pulses and the effect of laser fluence on the aerosol production have been also investigated. After optimization, the particle density in the sampling focal volume increases while improving the aerosol sampling rate till ca. 90%. - Highlights: • Aerosol generation by optical catapulting has been successfully optimized. • We study the evolution and dynamics of solid aerosols produced by OC. • We use shadowgraphy visualization as a diagnostic tool. • Effects of temporal conditions and laser fluence on the elevation of the aerosol cloud have been investigated. • The observed LIBS sampling rate increased from 50% reported before to approximately 90%.

  9. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere

    N. C. Bouvier-Brown

    2008-11-01

    Full Text Available We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments – a gas chromatograph with mass spectrometer detector (GC-MS, a proton transfer reaction mass spectrometer (PTR-MS, and a thermal desorption aerosol GC-MS (TAG – and found to be abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO, a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4–68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72–10.2 μgCg−1h−1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models.

  10. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere

    N. C. Bouvier-Brown

    2009-03-01

    Full Text Available We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments – a gas chromatograph with mass spectrometer detector (GC-MS, a proton transfer reaction mass spectrometer (PTR-MS, and a thermal desorption aerosol GC-MS (TAG – and found to be abundant within and above Blodgett Forest. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO, a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4–68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72–10.2 μgCg−1 h−1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models.

  11. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    Optical catapulting (OC) is a sampling and manipulation method that has been extensively studied in applications ranging from single cells in heterogeneous tissue samples to analysis of explosive residues in human fingerprints. Specifically, analysis of the catapulted material by means of laser-induced breakdown spectroscopy (LIBS) offers a promising approach for the inspection of solid particulate matter. In this work, we focus our attention in the experimental parameters to be optimized for a proper aerosol generation while increasing the particle density in the focal region sampled by LIBS. For this purpose we use shadowgraphy visualization as a diagnostic tool. Shadowgraphic images were acquired for studying the evolution and dynamics of solid aerosols produced by OC. Aluminum silicate particles (0.2–8 μm) were ejected from the substrate using a Q-switched Nd:YAG laser at 1064 nm, while time-resolved images recorded the propagation of the generated aerosol. For LIBS analysis and shadowgraphy visualization, a Q-switched Nd:YAG laser at 1064 nm and 532 nm was employed, respectively. Several parameters such as the time delay between pulses and the effect of laser fluence on the aerosol production have been also investigated. After optimization, the particle density in the sampling focal volume increases while improving the aerosol sampling rate till ca. 90%. - Highlights: • Aerosol generation by optical catapulting has been successfully optimized. • We study the evolution and dynamics of solid aerosols produced by OC. • We use shadowgraphy visualization as a diagnostic tool. • Effects of temporal conditions and laser fluence on the elevation of the aerosol cloud have been investigated. • The observed LIBS sampling rate increased from 50% reported before to approximately 90%

  12. Using Monte Carlo transport to accurately predict isotope production and activation analysis rates at the University of Missouri research reactor

    A detailed Monte Carlo N-Particle Transport Code (MCNP5) model of the University of Missouri research reactor (MURR) has been developed. The ability of the model to accurately predict isotope production rates was verified by comparing measured and calculated neutron- capture reaction rates for numerous isotopes. In addition to thermal (1/v) monitors, the benchmarking included a number of isotopes whose (n, γ) reaction rates are very sensitive to the epithermal portion of the neutron spectrum. Using the most recent neutron libraries (ENDF/ B-VII.0), the model was able to accurately predict the measured reaction rates in all cases. The model was then combined with ORIGEN 2.2, via MONTEBURNS 2.0, to calculate production of 99Mo from fission of low-enriched uranium foils. The model was used to investigate both annular and plate LEU foil targets in a variety of arrangements in a graphite irradiation wedge to optimize the production of 99Mo. (author)

  13. Daily cortisol production rate in man determined by stable isotope dilution/mass spectrometry

    Esteban, N.V.; Loughlin, T.; Yergey, A.L.; Zawadzki, J.K.; Booth, J.D.; Winterer, J.C.; Loriaux, D.L. (National Institute of Child Health and Human Development, Bethesda, MD (USA))

    1991-01-01

    Growth retardation as well as the development of Cushingoid features in adrenally insufficient patients treated with the currently accepted replacement dose of cortisol (33-41 mumol/day.m2; 12-15 mg/m2.day) prompted us to reevaluate the cortisol production rate (FPR) in normal subjects and patients with Cushing's syndrome, using a recently developed thermospray liquid chromatography-mass spectrometry method. The stable isotope (9,12,12-2H3)cortisol was infused continuously for 31 h at about 5% of the anticipated FPR. Blood samples were obtained at 20-min intervals for 24 h, spun, and pooled in 4-h groups. Tracer dilution in plasma was determined by liquid chromatography/mass spectrometry. The method was validated with controlled infusions in 6 patients with adrenal insufficiency. Results from 12 normal volunteers revealed a FPR of 27.3 +/- 7.5 mumol/day (9.9 +/- 2.7 mg/day) or 15.7 mumol/day.m2; 5.7 mg/m2. day. A previously unreported circadian variation in FPR was observed. Patients with Cushing's syndrome demonstrated unequivocal elevation of FPR and cortisol concentration correlated during each sample period in normal volunteers, indicating that cortisol secretion, rather than metabolism, is mainly responsible for changes in plasma cortisol. Our data suggest that the FPR in normal subjects may be lower than previously believed.

  14. A method for measuring tritium production rate by lithium-glass scintillators

    A method for measuring tritium production rate (TPR) of 6Li using 6Li, 7Li-glass scintillators has been developed for applying to fusion neutronics experiments. Advantages of this method are as follows. (1) No heavy irradiation is required because of high sensitivity, and (2) on-line measurement is capable. The γ-ray background is removed by subtracting the pulse height spectrum of 7Li-glass scintillator from that of 6Li-glass scintillator. The ratio of γ-ray detection efficiencies of two scintillators, which is used for the subtraction was determined experimentally. The contribution of competing reactions such as 6Li(n,n'd)4He reaction were estimated by kinematical analyses. An evaluation was carried out on self-shielding effect and escape of α-particles and tritons from the scintillator. This method was applied to the measurement of TPR distribution in a simulated fusion blanket assembly bombarded by D-T neutrons. The result was compared with that of neutron transport calculation with a satisfactory agreement. It has been shown that this method is very effective for fusion neutronics experiments. (author)

  15. Giotto IMS measurements of the production rate of hydrogen cyanide in the coma of Comet Halley

    Ip, W.-H.; Balsiger, H.; Geiss, J.; Goldstein, B. E.; Kettmann, G.

    1990-01-01

    The ion composition measurements in the ionosphere of Comet Halley by the ion mass spectrometer (IMS) experiment on the Giotto spacecraft are used to estimate the relative abundance of HCN. From a comparison of the normalized number density of ions with mass-to-charge (M/q) ratio of 28 AMU/e with steady-state photochemical models, it can be determined that the production rate of HCN directly from the central nucleus is Q(HCN) is less than about 0.0002 Q(H2O) at the time of Giotto encounter. The related photochemical- model calculations also indicate that Q(NH3)/Q(H2O) at the time of Giotto encounter. The related photo-chemical model calculations also indicate that Q(HN3)/Q(H2O) equals about 0.005, in agreement with recent determination from ground-based observations. The estimated value of Q(HCN) is lower than the relative abundance of Q(HCN)/Q(H2O) of about 0.001, as derived from radio observations of the 88.6 GHz emission of the J = 1 - 0 transition of HCN. The difference may be the result of time variations of the coma composition and dynamics, as well as other model-dependent effects.

  16. Daily cortisol production rate in man determined by stable isotope dilution/mass spectrometry

    Growth retardation as well as the development of Cushingoid features in adrenally insufficient patients treated with the currently accepted replacement dose of cortisol (33-41 mumol/day.m2; 12-15 mg/m2.day) prompted us to reevaluate the cortisol production rate (FPR) in normal subjects and patients with Cushing's syndrome, using a recently developed thermospray liquid chromatography-mass spectrometry method. The stable isotope [9,12,12-2H3]cortisol was infused continuously for 31 h at about 5% of the anticipated FPR. Blood samples were obtained at 20-min intervals for 24 h, spun, and pooled in 4-h groups. Tracer dilution in plasma was determined by liquid chromatography/mass spectrometry. The method was validated with controlled infusions in 6 patients with adrenal insufficiency. Results from 12 normal volunteers revealed a FPR of 27.3 +/- 7.5 mumol/day (9.9 +/- 2.7 mg/day) or 15.7 mumol/day.m2; 5.7 mg/m2. day. A previously unreported circadian variation in FPR was observed. Patients with Cushing's syndrome demonstrated unequivocal elevation of FPR and cortisol concentration correlated during each sample period in normal volunteers, indicating that cortisol secretion, rather than metabolism, is mainly responsible for changes in plasma cortisol. Our data suggest that the FPR in normal subjects may be lower than previously believed

  17. Control of the flow rate in decreasing of the water load of peat production

    The retention capacity and control of the flow rate was studied in the Aqua-Peat research. The sedimentation ability of solid matter (peat particles), erosion, migration of the solid matter, and the functioning of the retention pipes located in the strip ditches and the sedimentation basins were measured in the research. Detection was also supplemented by laboratory scale models and by measurements made using them. A model, describing the solid matter erosion and migration on the mire, was compiled on the basis of the results. Migration of the solid matter is possible to reduce by pounding the water into the ditching. So there is more time for particles to settle before migration into watercources. By this method it is possible to reduce the solid matter loads caused by heavy rains and power-flows even by 88 %. If the flow control system is equipped with retainers and settling basins, the solid matter retention capacity can rise up to 93-97 %. The results have shown that the retention pipe retainers play more important role in reduction of solid matter load than sedimentation basins. A follow-up study was made using several types of retainers. A 5 cm thick siphon pipe appeared to be the best. The final selection of the retention pipes has, however, to be made as a compromise between the functioning of the drying process, production possibilities and solid matter retention. (1 ref., 2 figs.)

  18. Cosmogenic nuclide production rates as a function of latitude and altitude calculated via a physics based model and excitation functions

    Argento, D.; Reedy, R. C.; Stone, J. O.

    2012-12-01

    Cosmogenic nuclides have been used to develop a set of tools critical to the quantification of a wide range of geomorphic and climatic processes and events (Dunai 2010). Having reliable absolute measurement methods has had great impact on research constraining ice age extents as well as providing important climatic data via well constrained erosion rates, etc. Continuing to improve CN methods is critical for these sciences. While significant progress has been made in the last two decades to reduce uncertainties (Dunai 2010; Gosse & Phillips 2001), numerous aspects still need to be refined in order to achieve the analytic resolution desired by glaciologists and geomorphologists. In order to investigate the finer details of the radiation responsible for cosmogenic nuclide production, we have developed a physics based model which models the radiation cascade of primary and secondary cosmic-rays through the atmosphere. In this study, a Monte Carlo method radiation transport code, MCNPX, is used to model the galactic cosmic-ray (GCR) radiation impinging on the upper atmosphere. Beginning with a spectrum of high energy protons and alpha particles at the top of the atmosphere, the code tracks the primary and resulting secondary particles through a model of the Earth's atmosphere and into the lithosphere. Folding the neutron and proton flux results with energy dependent cross sections for nuclide production provides production rates for key cosmogenic nuclides (Argento et al. 2012, in press; Reedy 2012, in press). Our initial study for high latitude shows that nuclides scale at different rates for each nuclide (Argento 2012, in press). Furthermore, the attenuation length for each of these nuclide production rates increases with altitude, and again, they increase at different rates. This has the consequence of changing the production rate ratio as a function of altitude. The earth's geomagnetic field differentially filters low energy cosmic-rays by deflecting them away

  19. The Gas Production Rate and Coma Structure of Comet C/1995 01 (Hale-Bopp)

    Morgenthaler, Jeffrey P.; Harris, Walter M.; Roesler, Frederick L.; Scherb, Frank; Anderson, Christopher M.; Doane, Nathaniel E.; Oliversen, Ronald J.

    2002-01-01

    The University of Wisconsin-Madison and NASA-Goddard conducted a comprehensive multi-wavelength observing campaign of coma emissions from comet Hale-Bopp, including OH 3080 A, [O I] 6300 A, H2O(+) 6158 A, H Balmer-alpha 6563 A, NH2 6330 A, [C I] 9850 A CN 3879 A, C2 5141 A, C3 4062 A, C I 1657 A, and the UV and optical continua. In this work, we concentrate on the results of the H2O daughter studies. Our wide-field OH 3080 A measured flux agrees with other, similar observations and the expected value calculated from published water production rates using standard H2O and OH photochemistry. However, the total [O I] 6300 A flux determined spectroscopically over a similar field-of-view was a factor of 3 - 4 higher than expected. Narrow-band [O I] images show this excess came from beyond the H2O scale length, suggesting either a previously unknown source of [O I] or an error in the standard OH + upsilon to O((sup I)D) + H branching ratio. The Hale-Bopp OH and [O I] distributions, both of which were imaged to cometocentric distances greater than 1 x 10(exp 6) km, were more spatially extended than those of comet Halley (after correcting for brightness differences), suggesting a higher bulk outflow velocity. Evidence of the driving mechanism for this outflow is found in the H(alpha) line profile, which was narrower than in comet Halley (though likely because of opacity effects, not as narrow as predicted by Monte-Carlo models). This is consistent with greater collisional coupling between the suprathermal H photodissociation products and Hale-Bopp's dense coma. Presumably because of mass loading of the solar wind by ions and ions by the neutrals, the measured acceleration of H2O(+) down the ion tail was much smaller than in comet Halley. Tailward extensions in the azimuthal distributions of OH 3080 A, [O I], and [C I], as well as a Doppler asymmetry in the [O I] line profile, suggest ion-neutral coupling. While the tailward extension in the OH can be explained by increased

  20. Stellar production and destruction rates of the radioactive isotope 60Fe

    In the framework of this thesis astrophysically relevant, nuclear-physical rates, which are important for the understanding of the observed abundance of the long-lived isotope 60Fe, were measured at the GSI Helmholtz-Center for Heavy Ion Research GmbH and at the TRIGA research ractor in Mainz. First the Coulomb breakup of 59Fe and 60Fe was studied at the GSI Helmholtz-Center for Heavy Ion Research GmbH. For the production of the radioactive beams a 64Ni was led on a spallation target. In the fragment separator the isotopes were separated concerning their magnetic stiffness and only the wanted species studied in the LAND/R3B setup. The determination of momentum and charge of the incoming ions allowed an individual identification. The Coulomb breakup cros sections was determined with a lead sample. The different background components resulted from an accompanying empty measurement as well as a measurement with a carbon sample. The cross section of the reaction Pb(60Fe,n+59Pb) at (530±5) MeV/u was determined to σCOULEX(60Fe,n+59Fe) = (298±11stat±31syst) mb, and for the reaction Pb(59Fe,n+58Fe)Pb resulted σCOULEX(59Fe,n+58Fe) = (410±11stat±41syst) mb. Furthermore for both incoming beam kinds the probabilities for the production of two neutrons could be determined. In the following the neutron-capture cross section of 60Fe at kT=25.3 meV was determined at the TRIGA research reactor in Mainz. For this an 60Fe sample was first characterized by means of the increasement of the activity of the 60Co daughter nu and in the following irradiated in the reactor. The directly produced activity of the 61Fe was detected with a HPGe detector. By means of the cadmium-difference method by this for the first time the thermal neutron-capture cross section of 60Fe could be determined to σth60Fe(n,γ) = 0.22±0.02stat±0.02syst b. For the resonance integral the upper bound of Ires60Fe(n,γ) = 0.61 b resulted.

  1. Boosting Autofermentation Rates and Product Yields with Sodium Stress Cycling: Application to Production of Renewable Fuels by Cyanobacteria ▿ †

    Carrieri, Damian; Momot, Dariya; Brasg, Ian A.; Ananyev, Gennady; Lenz, Oliver; Bryant, Donald A.; Dismukes, G. Charles

    2010-01-01

    Sodium concentration cycling was examined as a new strategy for redistributing carbon storage products and increasing autofermentative product yields following photosynthetic carbon fixation in the cyanobacterium Arthrospira (Spirulina) maxima. The salt-tolerant hypercarbonate strain CS-328 was grown in a medium containing 0.24 to 1.24 M sodium, resulting in increased biosynthesis of soluble carbohydrates to up to 50% of the dry weight at 1.24 M sodium. Hypoionic stress during dark anaerobic ...

  2. Estimation of the rate of energy production of rat mast cells in vitro

    Johansen, Torben

    1983-01-01

    Rat mast cells were treated with glycolytic and respiratory inhibitors. The rate of adenosine triphosphate depletion of cells incubated with both types of inhibitors and the rate of lactate produced in presence of antimycin A and glucose were used to estimate the rate of oxidative and glycolytic...

  3. Development and application of an on-line tritium production rate measuring method

    A highly sensitive on-line method for measuring the tritium production rate (TPR) of 6Li was developed using the response difference of 6Li and 7Li-glass scintillators in a mixed neutron-gamma radiation field. A fitting method for subtracting the pulse height spectrum of 7Li-glass from that of 6Li-glass was introduced. The contribution of competing reactions such as 6Li (n, n 'd) 4He was estimated by kinematical analyses. An absolute value of the 6Li content was determined by a chemical analysis. The thermal flux perturbation due to 6Li-glass of various thickness and 6Li contents was evaluated by measurement in a thermal neutron field and calculation by the modified Skyrme theory. A Monte Carlo calculation of the self-shielding effect was also made. The dependence of the self-shielding on neutron energy was examined by this Monte Carlo code. The edge effect, i.e., distortion of the pulse height spectrum due to partial energy deposition of the alpha and/or the triton, was investigated by measurement in a thermal neutron field and by a Monte Carlo simulation that was based on the scintillation mechanism and considered Bragg absorption and the ratio of contributions to luminescence by the alpha and the triton. The dependence of the edge effect on neutron energy was examined by this Monte Carlo code. This method was applied to the measurement of TPR distributions in simulated fusion blanket assemblies bombarded by D-T neutrons. Absolute values of the TPR were obtained with an experimental error of 3∼6 %. The measured results were compared with those of conventional β-counting methods and good agreement was obtained. An optical fiber system, using miniature lithium-glass scintillators, was fabricated for purpose of microminiaturization of detector size and adaption to strong electromagnetic field. Applicability of this system to a D-T neutron field was demonstrated. (author)

  4. Effect of feeding diet containing protected protein on volatile fatty acids production rate and passage rate of digesta in crossbred cattle

    Twelve crossbred rumen fistulated male cattle were divided into 3 groups (A,B and C). All the animals were fed concentrate mixture according to their requirement and wheat straw ad lib. However, ground nut cake (GNC) of concentrate mixture in group A (0 per cent), B (50 per cent) and C (100 per cent) were treated with formaldehyde. Dry matter intake and digestibility of proximate principles and fibre were similar in 3 groups. TVFA (total volatile fatty acids) content in rumen fluid was 8.92 ± 0.31, 8.87 ± 0.06 and 9.40 ± 0.48 m mol/100 SRL (P > 0.05) in groups A, B and C, respectively. Molar percentage of acetate and propionate were not affected by treatment. On the other hand, molar percentage of butyrate was significantly lower in group C. Production rate of volatile fatty acids was 10.48 ± 0.57, 9.70 ± 0.51 and 9.19 ± 0.35 mol/day (P > 0.05) in groups A, B and C, respectively. While flow rate of liquid digesta was significantly lower in group B and C than in group A, passage rate of solid digesta was not affected due to protected protein in diet. However, passage rate of solid digesta as per cent of total DM in rumen at zero hour was significantly higher in animals fed protected protein. Thus, the incorporation of formaldehyde treated protein in diet decreased the VFA production and outflow of liquid digesta but did not affect (P > 0.05) the passage rate of solid digesta and digestibility coefficients of various nutrients. (author). 28 refs., 2 tabs., 2 figs

  5. Aquaponics: integrating fish feeding rates and ion waste production for strawberry hydroponics

    Villarroel, Morris; Rodriguez Alvariño, Jose Mario; Duran Altisent, Jose Maria

    2011-01-01

    Aquaponics is the science of integrating intensive fish aquaculture with plant production in recirculating water systems. Although ion waste production by fish cannot satisfy all plant requirements, less is known about the relationship between total feed provided for fish and the production of milliequivalents (mEq) of different macronutrients for plants, especially for nutrient flow hydroponics used for strawberry production in Spain. That knowledge is essential to consider the amount of mac...

  6. Production of 26Al, 44Ti and 60Fe in Supernovae-sensitivity to the helium burning rates

    Tur, Clarisse; Austin, Sam M

    2010-01-01

    We have studied the sensitivity of supernova production of the gamma emitting nuclei 26Al, 44Ti and 60Fe to variations of the rates of the triple alpha and 12C(alpha, gamma) reactions. Over a range of twice their experimental uncertainties we find variations in the production of 60Fe by more than a factor of five. Smaller variations, about a factor of two to three, were observed for 26Al and 44Ti. The yields of these isotopes change significantly when the abundances of Lodders (2003) are used instead of those of Anders and Grevesse (1989). These sensitivities will limit conclusions based on a comparison of observed gamma ray intensities and stellar models until the helium burning rates are better known. Prospects for improving the helium burning rates are discussed and a new version of the Boyes rate for 12C(alpha, gamma} is presented.

  7. Seasonal Changes in Mycosporine-Like Amino Acid Production Rate with Respect to Natural Phytoplankton Species Composition

    Sun-Yong Ha

    2015-11-01

    Full Text Available After in situ incubation at the site for a year, phytoplanktons in surface water were exposed to natural light in temperate lakes (every month; thereafter, the net production rate of photoprotective compounds (mycosporine-like amino acids, MAAs was calculated using 13C labeled tracer. This is the first report describing seasonal variation in the net production rate of individual MAAs in temperate lakes using a compound-specific stable isotope method. In the mid-latitude region of the Korean Peninsula, UV radiation (UVR usually peaks from July to August. In Lake Paldang and Lake Cheongpyeong, diatoms dominated among the phytoplankton throughout the year. The relative abundance of Cyanophyceae (Anabaena spiroides reached over 80% during July in Lake Cheongpyeong. Changes in phytoplankton abundance indicate that the phytoplankton community structure is influenced by seasonal changes in the net production rate and concentration of MAAs. Notably, particulate organic matter (POM showed a remarkable change based on the UV intensity occurring during that period; this was because of the fact that cyanobacteria that are highly sensitive to UV irradiance dominated the community. POM cultured in Lake Paldang had the greatest shinorine (SH production rate during October, i.e., 83.83 ± 10.47 fgC·L−1·h−1. The dominance of diatoms indicated that they had a long-term response to UVR. Evaluation of POM cultured in Lake Cheongpyeong revealed that there was an increase in the net MAA production in July (when UVR reached the maximum; a substantial amount of SH, i.e., 17.62 ± 18.34 fgC·L−1·h−1, was recorded during this period. Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure. In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae.

  8. Estimates of rates and errors for measurements of direct-. gamma. and direct-. gamma. + jet production by polarized protons at RHIC

    Beddo, M.E.; Spinka, H.; Underwood, D.G.

    1992-08-14

    Studies of inclusive direct-{gamma} production by pp interactions at RHIC energies were performed. Rates and the associated uncertainties on spin-spin observables for this process were computed for the planned PHENIX and STAR detectors at energies between {radical}s = 50 and 500 GeV. Also, rates were computed for direct-{gamma} + jet production for the STAR detector. The goal was to study the gluon spin distribution functions with such measurements. Recommendations concerning the electromagnetic calorimeter design and the need for an endcap calorimeter for STAR are made.

  9. International Production Networks and Export/Import Responsiveness to Exchange Rates: The case of Japanese manufacturing firms

    Ando, Mitsuyo; Akie IRIYAMA

    2009-01-01

    This paper examines how international production/distribution networks provide individual firms with exporting/importing responsiveness to exchange rate movements. With the micro-data of Japanese manufacturing firms from 1994 to 2004, we find that firms' exports tend to respond to exchange rate movements, in particular (1) when firms are large in size, (2) when majority-owned affiliates are dominant among their foreign affiliates, and (3) when their intra-firm trade ratio is moderately high. ...

  10. Energy, the Exchange Rate, and the Economy; Macroeconomic Benefits of Canada’s Oil Sands Production

    Tamim Bayoumi; Martin Mühleisen

    2006-01-01

    This paper describes potential benefits from Canada's expanding oil sands production, higher energy exports, and further improvements in the terms of trade. Contrary to the previous Canadian exchange rate literature, this paper finds that both energy and nonenergy commodity prices have an influence on the Canadian dollar, and some upward pressure on the exchange rate would therefore be expected. Model results suggest, however, that the impact on other tradable goods exports is limited.

  11. The Optimal Replenishment Policy under Trade Credit Financing with Ramp Type Demand and Demand Dependent Production Rate

    Juanjuan Qin

    2014-01-01

    Full Text Available This paper investigates the optimal replenishment policy for the retailer with the ramp type demand and demand dependent production rate involving the trade credit financing, which is not reported in the literatures. First, the two inventory models are developed under the above situation. Second, the algorithms are given to optimize the replenishment cycle time and the order quantity for the retailer. Finally, the numerical examples are carried out to illustrate the optimal solutions and the sensitivity analysis is performed. The results show that if the value of production rate is small, the retailer will lower the frequency of putting the orders to cut down the order cost; if the production rate is high, the demand dependent production rate has no effect on the optimal decisions. When the trade credit is less than the growth stage time, the retailer will shorten the replenishment cycle; when it is larger than the breakpoint of the demand, within the maturity stage of the products, the trade credit has no effect on the optimal order cycle and the optimal order quantity.

  12. Productive responses of breeding Cashmere goats and their kids to different stocking rates on improved upland pastures.

    Celaya, R; Moreno-Gonzalo, J; López López, C; Ferreira, L M M; García, U; Ferre, I; Osoro, K

    2016-03-01

    Although goat meat production could be an option for diversification in improved upland pastures in northern Spain, precise information on the optimal grazing management to enhance goat performance and maximize production per unit land area is lacking. The objective of this study was to compare the effects of 3 stocking rates, high stocking rate (HSR; 20 goats/ha), medium stocking rate (MSR; 15 goats/ha), and low stocking rate (LSR; 10 goats/ha), on gastrointestinal (GI) nematode infections and productive responses of Cashmere goats grazing such pastures. Treatments were replicated twice on 6 paddocks sown with and and with a high presence of the native grass . The experiment lasted 3 grazing seasons (from spring to autumn). Pastures were sampled for sward height and botanical and proximate composition. Body weight and BCS changes of goats were monitored and GI nematode infections were assessed by fecal egg counts (FEC). The established treatments resulted in lower mean sward height in the HSR than in the MSR and LSR (9.6, 11.5, and 14.4 cm, respectively; goats/ha could represent the best compromise between animal health, performance, and productivity per unit land area in this type of upland pastures, but stricter controls of parasite levels during the grazing season would be necessary to avoid production losses, unless alternative nutraceuticals are provided. PMID:27065288

  13. Two-stage high-rate biogas (H2 and CH4) production from food waste using anaerobic mixed microflora

    Xu, K.; Lee, D.; Kobayashi, T.; Ebie, Y.; Li, Y.; Inamori, Y.

    2010-12-01

    To achieve the high-rate H2 and CH4 production from food waste using fermentative anaerobic microflora, the effects of carbonate-alkalinity in the recirculated digestion sludge on continuous two-stage fermentation were investigated. Higher H2 production rate of 2.9 L-H2/L/day was achieved at the recycle ratio of 1.0 in an alkalinity range of 9000 to 10000 mg-CaCO3/L. The maximum CH4 production rate was stably maintained at the range of 1.85 to 1.88 L-CH4/L/day without alkalinity change. Carbonate alkalinity in digestion sludge could reduce the H2 partial pressure in the headspace of the fermentation reactors, and improve a biogas production capacity in the two-stage fermentation process. The average volatile solids degradation rate in the overall process increased as the digestion sludge recycle increased from 0.5 to 1.0. These results show that the alkalinity in recycle of the digestion sludge is crucial factor in determining biogas (H2 and CH4) production capacity and reducing the total solids.

  14. An Analysis of the Pass-Through of Exchange Rates in Tropical Forest Product Markets: A Smooth Transition Approach

    Guney, Selin

    2014-01-01

    This paper assesses exchange rate pass through for forest product prices, namely sawnwood, plywood, lumber spruce and logs prices by incorporating smooth structural changes. The major countries investigated are the USA, Japan (Tokyo), Nigeria (Sapele), Malaysia and Gabon and similar or identical products that are traded are examined. In keeping with Hanninen et al.(2000, 20006), paper examines regime-specific ERPT effects. Results suggest evidence for the convenience of the STAR type models (...

  15. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    Yiwen Liu; Qilin Wang; Yaobin Zhang; Bing-Jie Ni

    2015-01-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. Th...

  16. Implications of inflorescence clustering for the visitation rate by hummingbirds and fruit production by Heliconia bihai (L.) L. (Heliconiaceae)

    Caio César Corrêa Missagia; Fábio de Castro Verçoza

    2015-01-01

    Plant spatial distribution can influence the activity of floral visitors. Flower clustering in patches may be more attractive to visitors and it supposedly influences the fruit production. This study aimed to test the hypothesis that in Heliconia bihai (L.) L. (Heliconiaceae) the inflorescence clustering size positively influences the visitation rate and fruit production by the species. The study was conducted at a stretch of Atlantic Forest, in Rio de Janeiro city, Brazil. Five hummingbird s...

  17. The Importance of Considering Product Loss Rates in Life Cycle Assessment: The Example of Closure Systems for Bottled Wine

    Olivier Jolliet; Yves Loerincik; Jean-François Ménard; Richard Pfister; Amanda Pike; Elisa Tatti; Sebastien Humbert; Anna Kounina

    2012-01-01

    Purpose: The objective of this study is to discuss the implications of product loss rates in terms of the environmental performance of bottled wine. Wine loss refers to loss occurring when the consumer does not consume the wine contained in the bottle and disposes of it because of taste alteration, which is caused by inadequate product protection rendering the wine unpalatable to a knowledgeable consumer. The decision of whether or not to drink the wine in such cases is guided by subjective c...

  18. Radial Distribution of Production Rates, Loss Rates and Densities Corresponding to Ion Masses <=40 amu in the Inner Coma of Comet Halley: Composition and Chemistry

    Haider, S A; Bhardwaj, Anil

    2005-01-01

    In this paper we have studied the chemistry of C, H, N, O, and S compounds corresponding to ions of masses <=40 amu in the inner coma of the comet 1P/Halley. The production rates, loss rates, and ion mass densities are calculated using the Analytical Yield Spectrum approach and solving coupled continuity equation controlled by the steady state photochemical equilibrium condition. The primary ionization sources in the model are solar EUV photons, photoelectrons, and auroral electrons of the solar wind origin. The chemical model couples ion-neutral, electron-neutral, photon-neutral and electron-ion reactions among ions, neutrals, electrons, and photons through over 600 chemical reactions. Of the 46 ions considered in the model the chemistry of 24 important ions are discussed in this paper. The calculated ion mass densities are compared with the Giotto Ion Mass Spectrometer (IMS) and Neutral Mass Spectrometer (NMS) data at radial distances 1500, 3500, and 6000 km.

  19. The effects of rate of return and environmental regulations on the productivity performance in the US electric utility industry

    Productivity growth in the US electric power industry has been declining since the late 1960's. Rate of return regulation and environmental regulations are hypothesized to adversely affect the productivity performance. Employing a Divisa index of the total factor productivity (TEP) an electric utility's performance is measured based on a profit maximization framework subject to both regulatory constraints. The empirical analysis attempts to analyze the effects of these regulations on the productivity growth employing data from privately-owned, fossil-fueled electric utilities. Results show a consistent decline in productivity growth over time averaging at 2% annually during 1977 and 1982, as well as the existence of regional differences in TFP growth among utilities. It shows positive and significant relationships between TFP growth and the rate of return, regulatory lag, the use of future test year, and deferred tax credit in the rate-making process. In the environmental case, results show that a stringent emission standard, using scrubbers for sulfur reduction and the utilization of aging power plants all contribute to the decline in productivity growth

  20. Influence of temperature on corrosion rate and porosity of corrosion products of carbon steel in anoxic bentonite environment

    Highlights: •The corrosion rate is not significantly dependent on temperature. •Corrosion products at higher temperatures have different color. •Corrosion products at higher temperatures are more compact. •The change in corrosion products nature is reversible. -- Abstract: The study focuses on the porosity of layers of corrosion products and its impact on corrosion rate of carbon steel in moist bentonite. Measurements were performed in an aggressive Czech type of bentonite – Rokle B75 at temperatures of 90 and 40 °C. Aggressiveness of B75 bentonite consists in low content of chlorides. Presence of chlorides in pore solution allows formation of more protective magnetite. The evaluation was made by electrochemical techniques (red/ox potential, open circuit potential, linear polarization resistance, impedance spectroscopy) and resistometric sensor measurements. The result imply that the higher the temperature the more compact is the layer of corrosion products that slightly decelerates corrosion rate compared to the state at 40 °C. The state of corrosion products at both temperatures is reversible

  1. Displacement rate dependence of irradiation creep as predicted by the production bias model

    Woo, C.H.

    1996-04-01

    Recently, it has been shown that the non-swelling component of irradiation creep of austenitic stainless steels is relatively independent of temperature but is sensitive to the displacement rate. An earlier model of Lewthwaite and Mosedale anticipated the sensitivity of displacement rate and attributed it to the flux sensitivity of point defect recombination. The point-defect recombination process does not yield the observed temperature dependence, however, although it does predict an inverse dependence of the creep rate on the square root of the displacement rate that was experimentally observed at relatively low temperatures.

  2. Estimation of Oil Production Rates in Reservoirs Exposed to Focused Vibrational Energy

    Jeong, Chanseok

    2014-01-01

    Elastic wave-based enhanced oil recovery (EOR) is being investigated as a possible EOR method, since strong wave motions within an oil reservoir - induced by earthquakes or artificially generated vibrations - have been reported to improve the production rate of remaining oil from existing oil fields. To date, there are few theoretical studies on estimating how much bypassed oil within an oil reservoir could be mobilized by such vibrational stimulation. To fill this gap, this paper presents a numerical method to estimate the extent to which the bypassed oil is mobilized from low to high permeability reservoir areas, within a heterogeneous reservoir, via wave-induced cross-flow oscillation at the interface between the two reservoir permeability areas. This work uses the finite element method to numerically obtain the pore fluid wave motion within a one-dimensional fluid-saturated porous permeable elastic solid medium embedded in a non-permeable elastic semi-infinite solid. To estimate the net volume of mobilized oil from the low to the high permeability area, a fluid flow hysteresis hypothesis is adopted to describe the behavior at the interface between the two areas. Accordingly, the fluid that is moving from the low to the high permeability areas is assumed to transport a larger volume of oil than the fluid moving in the opposite direction. The numerical experiments were conducted by using a prototype heterogeneous oil reservoir model, subjected to ground surface dynamic loading operating at low frequencies (1 to 50 Hz). The numerical results show that a sizeable amount of oil could be mobilized via the elastic wave stimulation. It is observed that certain wave frequencies are more effective than others in mobilizing the remaining oil. We remark that these amplification frequencies depend on the formation’s elastic properties. This numerical work shows that the wave-based mobilization of the bypassed oil in a heterogeneous oil reservoir is feasible, especially

  3. Bacterial secondary production on vascular plant detritus: relationships to detritus composition and degradation rate.

    Moran, M.A. (María Asunción); Hodson, R E

    1989-01-01

    Bacterial production at the expense of vascular plant detritus was measured for three emergent plant species (Juncus effusus, Panicum hemitomon, and Typha latifolia) degrading in the littoral zone of a thermally impacted lake. Bacterial secondary production, measured as tritiated thymidine incorporation into DNA, ranged from 0.01 to 0.81 microgram of bacterial C mg of detritus-1 day-1. The three plant species differed with respect to the amount of bacterial productivity they supported per mil...

  4. Designing Flexible GUI to Increase the Acceptance Rate of Product Data Management Systems in Industry

    Ahmed, Zeeshan

    2011-01-01

    Product Data Management (PDM) desktop and web based systems maintain the organizational technical and managerial data to increase the quality of products by improving the processes of development, business process flows, change management, product structure management, project tracking and resource planning. Though PDM is heavily benefiting industry but PDM community is facing a very serious unresolved issue in PDM system development with flexible and user friendly graphical user interface fo...

  5. Phenotypic engineering of sperm-production rate confirms evolutionary predictions of sperm competition theory

    Sekii, Kiyono; Vizoso, Dita B.; Kuales, Georg; De Mulder, Katrien; Ladurner, Peter; Schärer, Lukas

    2013-01-01

    Sperm production is a key male reproductive trait and an important parameter in sperm competition theory. Under sperm competition, paternity success is predicted to depend strongly on male allocation to sperm production. Furthermore, because sperm production is inherently costly, individuals should economize in sperm expenditure, and conditional adjustment of the copulation frequency according to their sperm availability may be expected. However, experimental studies showing effects of sperm ...

  6. Integrated rate expression for the production of glucose equivalent in C4 green plant and the effect of temperature

    Anirban Panda; Sambhu N Datta

    2007-09-01

    A temperature-dependent integrated kinetics for the overall process of photosynthesis in green plants is discussed. The C4 plants are chosen and in these plants, the rate of photosynthesis does not depend on the partial pressure of O2. Using some basic concepts like chemical equilibrium or steady state approximation, a simplified scheme is developed for both light and dark reactions. The light reaction rate per reaction center ('1) in thylakoid membrane is related to the rate of exciton transfer between chlorophyll neighbours and an expression is formulated for the light reaction rate '1. A relation between '1 and the NADPH formation rate is established. The relation takes care of the survival probability of the membrane. The CO2 saturation probability in bundle sheath is also taken into consideration. The photochemical efficiency () is expressed in terms of these probabilities. The rate of glucose production is given by glucose = (8/3)('1L)()() ([G3P]/[i]2 leaf)SSG3P → glucose where is the activity quotient of the involved enzymes, and G3P represent glycealdehyde-3-phosphate in steady state. A Gaussian distribution for temperaturedependence and a sigmoid function for de-activation are incorporated through the quotient . In general, the probabilities are given by sigmoid curves. The corresponding parameters can be easily determined. The theoretically determined temperature-dependence of photochemical efficiency and glucose production rate agree well with the experimental ones, thereby validating the formalism.

  7. Estimates of future regional heavy oil production at three production rates--background information for assessing effects in the US refining industry

    This report is one of a series of publications from a project considering the feasibility of increasing domestic heavy oil (10 degree to 20 degree API gravity inclusive) production being conducted for the US Department of Energy. The report includes projections of future heavy oil production at three production levels: 900,000; 500,000; and 300,000 BOPD above the current 1992 heavy oil production level of 750,000 BOPD. These free market scenario projections include time frames and locations. Production projections through a second scenario were developed to examine which heavy oil areas would be developed if significant changes in the US petroleum industry occurred. The production data helps to define the possible constraints (impact) of increased heavy oil production on the US refining industry (the subject of a future report). Constraints include a low oil price and low rate of return. Heavy oil has high production, transportation, and refining cost per barrel as compared to light oil. The resource is known, but the right mix of technology and investment is required to bring about significant expansion of heavy oil production in the US

  8. Measuring primary production rates in the ocean: Enigmatic results between incubation and non-incubation methods at Station ALOHA

    Quay, P. D.; Peacock, C.; BjöRkman, K.; Karl, D. M.

    2010-09-01

    Primary production (PP) rates were estimated using concurrent 14C and 18O bottle incubations and a non-incubation oxygen isotope (17Δ) based method during monthly cruises to the time series station ALOHA in the subtropical N. Pacific Ocean between March, 2006 and February, 2008. The mean gross oxygen production (GOP) rate in the photic layer (0-200m) at ALOHA was estimated at 103 ± 43 and 78 ± 17 mmol O2 m-2 d-1 from the 17Δ and 18O methods, respectively. In comparison, the mean 14C-PP rate (daytime incubations) in the photic layer was 42 ± 7 mmol C m-2 d-1 (502 ± 84 mg C m-2 d-1). Seasonal and depth variability (% change) for GOP rate was 2-3 times that for 14C-PP. The non-incubation 17Δ-GOP rates consistently exceeded the incubation 18O-GOP rates by 25-60%, and possible methodological biases were evaluated. A supersaturation of the dissolved O2/Ar gas ratio was measured every month yielding a mean annual value of 101.3 ± 0.1% and indicating a consistent net autotrophic condition in the mixed layer at ALOHA. The mean annual net community production (NCP) rate at ALOHA estimated from dissolved O2/Ar gas ratio was 14 ± 4 mmol O2 m-2 d-1 (120 ± 33 mg C m-2 d-1 or 3.7 ± 1.0 mol C m-2 yr-1) for the mixed layer. A NCP/GOP ratio of 0.19 ± 0.08 determined from 17Δ and O2/Ar measurements indicated that ˜20% of gross photosynthetic production was available for export and harvest.

  9. Study of Biogas Production Rate from Water Hyacinth by Hydrothermal Pretreatment with Buffalo Dung as a Starter

    Teguh Kurniawan

    2014-08-01

    Full Text Available In this paper we report the effects of hydrothermal pretreatment on biogas enhancement production rates from water hyacinth mixed with buffalo dung. The focus of the experiment was on the time of hydrothermal pretreatment and the ratio of water hyacinth with buffalo dung. The hydrothermal pretreated substrates were characterized by TDS, BOD and pH. The hydrothermal pretreatment of 60 minutes with the ratio of water hyacinth to buffalo dung 1:2 showed the highest biogas production rate at 7889 ml/day. However, the highest methane composition was 52.82% which resulted on the hydrothermal treatment of 30 minutes with equal ratio of water hyacinth and buffalo dung. Thus, the optimum of methane yield obtained at hydrothermal pretreatment for 30 minutes with equal ratio of water hyacinth to buffalo dung is 2856 ml/day. The hydrothermal pretreatment increases the rate production of biogas 102% and the methane yield 51% relative to untreated water hyacinth. The ratio of water hyacinth and buffalo dung has a great impact on biogas production rate and compositions for hydrothermal pretreated substrates.

  10. On the accounting of technology progress rates and obsolescence of production funds when determining depreciation for NPP renovation

    Questions, related to determining the economically grounded service life of NPP main production funds are considered. It is recommended to differentiate the depreciation standards by the operation duration. It is proposed to arrange the NPP buildings taking into account modern rates of technical progress in power engineering

  11. The Influence of New Product Characteristics on Rate of Adoption: Increasing Student Comprehension with the "Bidding for Buyers" Game

    Vander Schee, Brian A.

    2012-01-01

    The five characteristics that influence new product rate of adoption are routinely covered in the Principles of Marketing course. Any particular marketing concept such as relative advantage, compatibility, complexity, divisibility, and communicability may not capture interest or engagement among students who take the course as a graduation…

  12. Variability and plasticity of productivity, water-use efficiency, and nitrogen exportation rate in Salix short rotation coppice

    Short rotation coppice (SRC) willow plantations may play an important role in the future for biomass production purposes. However, the high planting density schemes combined with the frequent harvests occurring in such plantations could rapidly deplete soil resources. The use of genotypes able to produce greater amounts of biomass by using the least water and nutrients may help mitigating this risk. This study aimed at assessing among six willow genotypes (1) the variability of traits related to productivity (e.g. aboveground dry biomass or stem height), leaf and wood nitrogen (N) contents, N exportation rate and water-use efficiency (WUE) as estimated through bulk leaf carbon isotope discrimination (Δ13C), (2) the relationships among traits, and (3) the plasticity of these traits and of the relationships among them across different sites. The six genotypes were grown under SRC at three sites in northern France differing primarily in pedoclimatic characteristics for two years. A significant genotypic variability was found for all traits, except for the N exportation rate. The pedoclimatic context impacted the values of all traits, and the genotypic ranking for traits related to productivity and for Δ13C. Δ13C was negatively correlated with total shoot dry biomass and/or height irrespective of the site, meaning that the most productive genotypes were also the most efficient to use water. In conclusion, no antagonism was detected between biomass production and WUE. The most productive and most water-use efficient genotypes were the ones responsible for the highest nitrogen removal from the plantation during harvest. -- Highlights: •Large genotypic variation for traits related to productivity and WUE. •High plasticity of studied traits. •Stable genotypic ranking for traits related to biomass production across sites. •Strong relationships between Δ13C and biomass production. •Low Δ13C indicates high productivity

  13. Power Spectrum Analyses of Nuclear Decay Rates

    Javorsek, D; Lasenby, R N; Lasenby, A N; Buncher, J B; Fischbach, E; Gruenwald, J T; Hoft, A W; Horan, T J; Jenkins, J H; Kerford, J L; Lee, R H; Longman, A; Mattes, J J; Morreale, B L; Morris, D B; Mudry, R N; Newport, J R; O'Keefe, D; Petrelli, M A; Silver, M A; Stewart, C A; Terry, B; 10.1016/j.astropartphys.2010.06.011

    2010-01-01

    We provide the results from a spectral analysis of nuclear decay data displaying annually varying periodic fluctuations. The analyzed data were obtained from three distinct data sets: 32Si and 36Cl decays reported by an experiment performed at the Brookhaven National Laboratory (BNL), 56Mn decay reported by the Children's Nutrition Research Center (CNRC), but also performed at BNL, and 226Ra decay reported by an experiment performed at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. All three data sets exhibit the same primary frequency mode consisting of an annual period. Additional spectral comparisons of the data to local ambient temperature, atmospheric pressure, relative humidity, Earth-Sun distance, and their reciprocals were performed. No common phases were found between the factors investigated and those exhibited by the nuclear decay data. This suggests that either a combination of factors was responsible, or that, if it was a single factor, its effects on the decay rate experiments are n...

  14. High-rate continuous hydrogen production by Thermoanaerobacterium thermosaccharolyticum PSU-2 immobilized on heat-pretreated methanogenic granules

    O-Thong, Sompong [Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet 115, DK-2800, Kgs Lyngby (Denmark); Department of Biology, Faculty of Science, Thaksin University, Patthalung 93110 (Thailand); Prasertsan, Poonsuk [Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Hat-Yai, Songkhla 90120 (Thailand); Karakashev, Dimitar; Angelidaki, Irini [Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet 115, DK-2800, Kgs Lyngby (Denmark)

    2008-11-15

    Biohydrogen production from Thermoanaerobacterium thermosaccharolyticum strain PSU-2 was examined in upflow anaerobic sludge blanket (UASB) reactor and carrier-free upflow anaerobic reactor (UA), both fed with sucrose and operating at 60 C. Heat-pretreated methanogenic granules were used as carrier to immobilize T. thermosaccharolyticum strain PSU-2 in UASB reactor operated at a hydraulic retention time (HRT) ranging from 0.75 to 24 h and corresponding sucrose loading rate from 58.5 to 2.4 mmol sucrose l{sup -1} h{sup -1}. In comparison with hydrogen production rate of 12.1 mmol H{sub 2} l{sup -1} h{sup -1} obtained by carrier-free reactor upflow anaerobic (UA) system, a greatly improved hydrogen production rate up to 152 mmol H{sub 2} l{sup -1} h{sup -1} was demonstrated by the granular cells in UASB system. The biofilm of T. thermosaccharolyticum strain PSU-2 developed on treated methanogenic granules in UASB reactor substantially enhanced biomass retention (3 times), and production of hydrogen (12 times) compared to carrier-free reactor. It appears to be the most preferred process for highly efficient dark fermentative hydrogen production from sugar containing wastewater under thermophilic conditions. (author)

  15. The effects of air temperature on office workers' well-being, workload and productivity-evaluated with subjective ratings.

    Lan, Li; Lian, Zhiwei; Pan, Li

    2010-12-01

    Productivity bears a close relationship to the indoor environmental quality (IEQ), but how to evaluate office worker's productivity remains to be a challenge for ergonomists. In this study, the effect of indoor air temperature (17 °C, 21 °C, and 28 °C) on productivity was investigated with 21 volunteered participants in the laboratory experiment. Participants performed computerized neurobehavioral tests during exposure in the lab; their physiological parameters including heart rate variation (HRV) and electroencephalograph (EEG) were also measured. Several subjective rating scales were used to tap participant's emotion, well-being, motivation and the workload imposed by tasks. It was found that the warm discomfort negatively affected participants' well-being and increased the ratio of low frequency (LF) to high frequency (HF) of HRV. In the moderately uncomfortable environment, the workload imposed by tasks increased and participants had to exert more effort to maintain their performance and they also had lower motivation to do work. The results indicate that thermal discomfort caused by high or low air temperature had negative influence on office workers' productivity and the subjective rating scales were useful supplements of neurobehavioral performance measures when evaluating the effects of IEQ on productivity. PMID:20478555

  16. Neutron production rates during four transitions from DT to D3He ignited plasmas in a compact tokamak

    Neutron production rates (due to DT, DD, TT and T3He reactions) and D3He reaction rate during four transitions from DT to D3He ignited plasmas (characterized by different evolutions of ion densities and temperature) in a compact tokamak have been calculated. In this paper, for each transition, the results are reported in graphical form (one curve for each reaction) and shortly discussed. The main feature is the predominance of 14 MeV DT-neutrons, whose production rate does not appear to be negligible. It is therefore concluded that while acceptable in experiments of D3He ignition, tritium-assistance may not be suitable for routine startup of D3He fusion power plants, in which plasma temperature will hae to be raised to ignition level probably by other means. Mention to a program aimed at measuring cross sections of some neutron-lean fusion reactions is also made

  17. Continuous fermentation and in-situ reed separation of butyric acid for higher sugar consumption rate and productivity

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter; Gavala, Hariklia N.

    fermentation coupled with Reverse Enhanced Electro-Dialysis (REED) at D=0.0417 h-1 (1 day HRT) in experiments with a mixture of glucose and xylose in synthetic growth medium as well as with increasing concentrations of PHWS (up to 100%). Data obtained from experiments with synthetic medium showed that...... disconnection of the REED system resulted to much lower (48 and 83% for glucose and xylose, respectively) sugars consumption rates and consequently lower butyric acid production rates. It was also noticeable that continuous operation, even without the REED system, resulted to higher glucose consumption rates...... development, and process improvement for higher yield, productivity and selectivity. Compared with other microbial strains Clostridium tyrobutyricum has been well characterised, exhibits higher yield and selectivity and can utilize glucose and xylose simultaneously. However, a prerequisite for cost effective...

  18. The Importance of Considering Product Loss Rates in Life Cycle Assessment: The Example of Closure Systems for Bottled Wine

    Olivier Jolliet

    2012-10-01

    Full Text Available Purpose: The objective of this study is to discuss the implications of product loss rates in terms of the environmental performance of bottled wine. Wine loss refers to loss occurring when the consumer does not consume the wine contained in the bottle and disposes of it because of taste alteration, which is caused by inadequate product protection rendering the wine unpalatable to a knowledgeable consumer. The decision of whether or not to drink the wine in such cases is guided by subjective consumer taste perception and wine quality expectation (drinking the bottle or disposing of the wine down the drain and replacing it with a new bottle. This study aims to illustrate the importance of accurately defining system boundaries related to wine packaging systems. Methods: The environmental impacts resulting from wine loss rates as related to two types of wine bottle closures—natural cork stoppers and screw caps—have been estimated based on literature review data and compared to the impact of the respective closure system. The system studied relates to the functional unit “a 750 mL bottle of drinkable wine” and includes bottled wine, bottle and closure production, wine production, wine loss and wine poured down the drain. Results: The range of wine alteration rates due to corked wine is estimated to be 2–5% based on interviews with wine experts. Consumer behavior was assessed through a sensitivity study on replacement rates. When the increase in loss rate with the cork stopper is higher than 1.2% (corresponding to 3.5% corked wine multiplied by a consumer replacement rate of 35%, the influence of losses on the impact results is higher than that of the closure material itself. The different closures and associated wine losses represent less than 5% of the total life cycle impact of bottled wine.

  19. Efficient methane production from lipid-rich wastewater in high-rate anaerobic treatment

    Cavaleiro, A. J.; Salvador, A. F.; Alves, M. M.

    2008-01-01

    In this work, high rate anaerobic mineralization of a synthetic dairy effluent containing 50% COD as oleic acid was accomplished in two reactors operated in parallel. The anaerobic reactors were able to accommodate organic loading rates up to 21 kg COD m-3 day-1, HRT of 9 hours, attaining 99% of soluble COD removal efficiency and methane yield higher than 70%. Long chain fatty acids (LCFA) accumulated inside the reactor only during the last two phases of operation and palmitic acid was ...

  20. High Biomass Specific Methyl Halide Production Rates of Selected Coastal Marsh Plants and its Relationship to Halide Content

    Manley, S. L.; Wang, N.; Cicerone, R. J.

    2002-12-01

    Salt tolerant coastal marsh plants (halophytes) have previously been shown to be globally significant producers of methyl chloride (MeCl) and methyl bromide (MeBr). While halophytes are known for their high salt content, there are few reports of their halide content. Our studies have attempted to quantify biomass specific methyl halide (MeX) production from these plants and relate it to tissue halide levels. MeCl, MeBr and MeI production rates and tissue chloride, bromide and iodide concentrations from selected coastal marsh plants were measured for nearly a year. Certain halophyte species (i.e. Batis and Frankenia) have very high summer biomass specific production rates for MeX (e.g. Frankenia: 1 ug MeCl /gfwt/hr; 80 ng MeBr/gfwt/hr; 8 ng MeI/gfwt/hr). These rates of MeCl and MeBr production are much higher than those from other coastal marsh plants or seaweeds. Plant halide levels remain high throughout the year, while MeX production peaks at a high level in mid summer falling to low winter rates. This implies a linkage to plant growth. Higher levels of chloride and bromide were seen in the fleshy marsh plants such as Batis (saltwort, approximately 20 percent dry wt chloride, 0.4 percent dry wt bromide) and Salicornia (pickleweed) than in the others such as Frankenia (alkali heath) approx 7 percent dry wt chloride, 0.1 percent dry wt bromide) or Spartina (cordgrass). No such trend was seen for iodide, which ranged from 4 - 10 ppm. Calculations show the daily halide losses from MeX production are far less than the variability in tissue halide content. MeX production removes a small fraction of the total tissue halide from these plants suggesting that MeX production is not a mechanism used by these species to control internal halide levels. Saltwort cell-free extracts incubated with bromide or iodide in the presence of S-adenosyl-L-methionine (SAM) produced the corresponding MeX. MeBr production was inhibited by caffeic acid the substrate of lignin-specific O

  1. Worker productivity and ventilation rate in a call center: Analyses of time-series data for a group of workers

    Fisk, William J.; Price, Phillip; Faulkner, David; Sullivan, Douglas; Dibartolomeo, Dennis; Federspiel, Cliff; Liu, Gang; Lahiff, Maureen

    2002-01-01

    In previous studies, increased ventilation rates and reduced indoor carbon dioxide concentrations have been associated with improvements in health at work and increased performance in work-related tasks. Very few studies have assessed whether ventilation rates influence performance of real work. This paper describes part one of a two-part analysis from a productivity study performed in a call center operated by a health maintenance organization. Outside air ventilation rates were manipulated, indoor air temperatures, humidities, and carbon dioxide concentrations were monitored, and worker performance data for advice nurses, with 30-minute resolution, were analyzed via multivariate linear regression to look for an association of performance with building ventilation rate, or with indoor carbon dioxide concentration (which is related to ventilation rate per worker). Results suggest that the effect of ventilation rate on worker performance in this call center was very small (probably less than 1%) or nil, over most of the range of ventilation rate experienced during the study (roughly 12 L s{sup -1} to 48 L s{sup -1} per person). However, there is some evidence suggesting performance improvements of 2% or more when the ventilation rate per person is very high, as indicated by indoor CO{sub 2} concentrations exceeding outdoor concentrations by less than 75 ppm.

  2. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  3. The Production Function Methodology for Calculating Potential Growth Rates & Output Gaps

    Karel Havik; Kieran Mc Morrow; Fabrice Orlandi; Christophe Planas; Rafal Raciborski; Werner Roeger; Alessandro Rossi; Anna Thum-Thysen; Valerie Vandermeulen

    2014-01-01

    This paper provides a detailed description of the current version of the Ecofin Council approved production function (PF) methodology which is used for assessing both the productive capacity (i.e. potential output) and cyclical position (i.e. output gaps) of EU economies. Compared with the previous 2010 paper on the same topic, there have been two significant changes to the PF methodology, namely an overhaul of the NAWRU methodology & the introduction of a new T+10 methodology.

  4. Modulation of the effects of alveolar macrophages on lung fibroblast collagen production rate

    Alveolar macrophages (AM) may function as effector cells that can either stimulate or inhibit lung fibroblast collagen production. However, conditions that determine the predominant effect of AM on fibroblasts are not well understood. To delineate factors that modulate the effects of AM on lung fibroblasts, we studied the interaction of AM products and fibroblasts in vitro. The AM were obtained by bronchoalveolar lavage of hamsters with bleomycin-induced pulmonary fibrosis. Conditioned medium (CM) from the AM cultures was incubated in varying amounts with lung fibroblast (IMR-90) cultures. After metabolic labeling with [3H]proline, fibroblast collagen production based on procollagen-specific radioactivity was determined. Macrophage CM in concentrations greater than 5% suppressed collagen production, an event attributed to the macrophage-derived suppressive factor that we have previously characterized. Macrophages were also determined to produce PGE2 in culture. Authentic PGE2 at concentrations found in CM was found to suppress fibroblast collagen production, indicating that AM-derived PGE2 contributes to the suppressive activity in CM. To examine possible stimulatory factors in CM, the fibroblasts were preincubated with indomethacin. This approach was based on our previous observation that AM-derived suppressive factor increases endogenous fibroblast PGE2 and that its activity can be blocked by indomethacin. Macrophage CM in a concentration of 20% did not suppress the collagen production of indomethacin-treated fibroblasts. However, CM concentrations of 5 and 10% increased collagen production (173 and 143% of control values, respectively), indicating the presence of stimulatory factor(s) in macrophage-conditioned medium

  5. Use of 13C-Labeled Substrates to Determine Relative Methane Production Rates in Hypersaline Microbial Communities

    Kelley, C. A.; Bebout, B.; Chanton, J.

    2015-12-01

    Rates and pathways of methane production were determined from photosynthetic soft microbial mats and gypsum-encrusted endoevaporites collected in hypersaline environments from California, Mexico and Chile, as well as an organic-rich mud from a pond in the El Tatio volcanic fields, Chile. Samples (mud, homogenized soft mats and endoevaporites) were incubated anaerobically with deoxygenated site water, and the increase in methane concentration through time in the headspaces of the incubation vials was used to determine methane production rates. To ascertain the substrates used by the methanogens, 13C-labeled methylamines, methanol, dimethylsulfide, acetate or bicarbonate were added to the incubations (one substrate per vial) and the stable isotopic composition of the resulting methane was measured. The vials amended with 13C-labeled methylamines produced the most 13C-enriched methane, generally followed by the 13C-labeled methanol-amended vials. The stable isotope data and the methane production rates were used to determine first order rate constants for each of the substrates at each of the sites. Estimates of individual substrate use revealed that the methylamines produced 55 to 92% of the methane generated, while methanol was responsible for another 8 to 40%.

  6. Fertility and productivity index rating of some soils conditioned by climate and topography

    In the humid tropics, well-drained soils with abundant loose iron concretions, soils with very little weatherable minerals left and of poor chemical status due to the abundance of low activity clays, pose serious limitations to agricultural productivity. Accurate and reliable soil productivity information is needed in the form of crop yield estimates and productivity indices. We investigated the productive potential of some acrisols and plinthosols by computing productivity indices (PI) and estimating yields of four test crops, namely cowpea, groundnut, maize and soybean. PI was based on physico-chemical parameters expected to regulate air-water relations, have a role in determining the mechanical resistance to crop roots and the volume of soil, and, contribute to the fertility status of the soils. Very low Pls in the order 7.2x10-5, 9.6x10-5 and 8.32x10-4 were observed for Nyankpala, Changnayili and Kpelesawgu series respectively. Based on the inherently low fertility status of these soils, maize, planted as a sole crop or in rotation with groundnut is the sustainable cropping system for the soils. A return of crop residue to the soil is envisaged as a long term practice to maintain adequate levels of organic matter. (author)

  7. The germanium isotopes production rate in background process in SAGE experiment

    The analysis of the direct determination of systematics connected with the germanium isotopes generation of in background processes in radiochemical SAGE experiments on measuring solar neutrinos is described. The found 68Ge generation rate is 6.5 (1 ± 1.0) times higher than expected; the generation rate of 69Ge does not exceed preliminary evaluations. The result on 68Ge corresponds to the systematic of cosmic ray muons of 5.8% (4.5 SNU) for the measured capture rate of solar neutrino of 77.0 SNU. To check the cosmic-ray muon influence of the SAGE systematic one suggests the experiment in place of underground scintillation telescope of the Baksan neutrino observatory on the Institute for Nuclear Research of the RAS

  8. Products from the high temperature pyrolysis of RDF at slow and rapid heating rates

    Efika, EC; Onwudili, JA; Williams, PT

    2015-01-01

    The high-temperature pyrolysis behaviour of a sample of refuse derived fuel (RDF) as a model of municipal solid waste (MSW) was investigated in a horizontal tubular reactor between 700 and 900 °C, at varying heating rates, and at an extended vapour residence time. Experiments were designed to evaluate the influence of process conditions on gas yields as well as gas and oil compositions. Pyrolysis of RDF at 800 °C and at rapid heating rate resulted in the gas yield with the highest CV of 24.8 ...

  9. Stellar production rates of carbon and its abundance in the universe

    Oberhummer, Heinz; Csoto, Attila; Schlattl, Helmut

    2000-01-01

    The bulk of the carbon in our universe is produced in the triple-alpha process in helium-burning red giant stars. We calculated the change of the triple-alpha reaction rate in a microscopic 12-nucleon model of the C-12 nucleus and looked for the effects of minimal variations of the strengths of the underlying interactions. Stellar model calculations were performed with the alternative reaction rates. Here, we show that outside a narrow window of 0.5 and 4% of the values of the strong and Coul...

  10. Production of Candida utilis Biomass and Intracellular Protein Content: Effect of Agitation Speed and Aeration Rate

    Rosma, A.; Ooi, K. I.

    2006-01-01

    The effects of agitation speed and aeration rate on the Candida utilis biomass and the intracellular protein content were investigated in this study. C. utilis inoculum of 10^6 cells/mL (7.8 % v/v) was cultured in 1.5 L pineapple waste medium (3 % Brix) in a 2-L fermentor for 30 h at 30 °C. Agitation speed and aeration rate have significant effects on the dissolved oxygen concentration, which in turn affect the cell growth and the intracellular protein content. The agitation speed of 100, 300...

  11. Left Ventricular Wall Stress-Mass-Heart Rate Product and Cardiovascular Events in Treated Hypertensive Patients

    Devereux, Richard B; Bang, Casper N; Roman, Mary J;

    2015-01-01

    In the Losartan Intervention for End Point Reduction in Hypertension (LIFE) study, 4.8 years' losartan- versus atenolol-based antihypertensive treatment reduced left ventricular hypertrophy and cardiovascular end points, including cardiovascular death and stroke. However, there was no difference in...... randomized treatment, the triple product was reduced more by atenolol, with prevalences of elevated triple product of 39% versus 51% on losartan (both P≤0.001). In Cox regression analyses adjusting for age, smoking, diabetes mellitus, and prior stroke, MI, and heart failure, 1 SD lower triple product was...... associated with 23% (95% confidence interval 13%-32%) fewer composite end points, 31% (18%-41%) less cardiovascular mortality, 30% (15%-41%) lower MI, and 22% (11%-33%) lower all-cause mortality (all P≤0.001), without association with stroke (P=0.34). Although losartan-based therapy reduced ventricular mass...

  12. Designing Flexible GUI to Increase the Acceptance Rate of Product Data Management Systems in Industry

    Ahmed, Zeeshan

    2011-01-01

    Product Data Management (PDM) desktop and web based systems maintain the organizational technical and managerial data to increase the quality of products by improving the processes of development, business process flows, change management, product structure management, project tracking and resource planning. Though PDM is heavily benefiting industry but PDM community is facing a very serious unresolved issue in PDM system development with flexible and user friendly graphical user interface for efficient human machine communication. PDM systems offer different services and functionalities at a time but the graphical user interfaces of most of the PDM systems are not designed in a way that a user (especially a new user) can easily learn and use them. Targeting this issue, a thorough research was conducted in field of Human Computer Interaction; resultant data provides the information about graphical user interface development using rich internet applications. The accomplished goal of this research was to suppor...

  13. The NEOWISE-Discovered Comet Population and the CO+CO2 production rates

    Bauer, James M; Kramer, Emily; Mainzer, A K; Grav, Tommy; Masiero, Joseph R; Fernández, Yan R; Cutri, Roc M; Dailey, John W; Masci, Frank J; Meech, Karen J; Walker, Russel; Lisse, C M; Weissman, Paul R; Nugent, Carrie R; Sonnett, Sarah; Blair, Nathan; Lucas, Andrew; McMillan, Robert S; Wright, Edward L; WISE, the

    2015-01-01

    The 163 comets observed during the WISE/NEOWISE prime mission represent the largest infrared survey to date of comets, providing constraints on dust, nucleus sizes, and CO+CO2 production. We present detailed analyses of the WISE/NEOWISE comet discoveries, and discuss observations of the active comets showing 4.6 $\\mu$m band excess. We find a possible relation between dust and CO+CO2 production, as well as possible differences in the sizes of long and short period comet nuclei.

  14. Weak boson production via vector-boson fusion rate at NLO matched with Powheg

    The production of weak vector-bosons in association with two jets is an important background to Higgs-boson searches in vector-Boson fusion (VBF) at the LHC. In order to make reliable predictions, the combination of fixed-order NLO-calculations and parton-showers is indispensable. We present the implementation of the weak boson production via VBF in the Powheg-Box. This is a first step to interface Vbfnlo, a fully flexible Monte Carlo program, with the Powheg-Box.

  15. Impact of ventilation rates on SBS symptoms and productivity in offices

    Wargocki, Pawel; Fanger, Povl Ole

    1999-01-01

    Perceived air quality, Sick Building Syndrome (SBS) symptoms and productivity were studied in a normally furnished office space ventilated with an outdoor air flow of 3, 10 and 30 L/s per person (corresponding to aiur changes of 0.6, 2.0 and 6 h-1, respectively), while all other environmental...... subjects occupied the office for 4.6 hours in the afternoon, six subjects at a time; they remained thermally neutral by adjusting their clothing. Subjects assessed perceived air quality and SBS symptoms, and performed simulated office work so that their productivity could be assessed. Increasing the supply...

  16. MODELING COMMERCIAL PROCESSES AND CUSTOMER BEHAVIORS TO ESTIMATE THE DIFFUSION RATE OF NEW PRODUCTS

    Alain BLOCH; Daniel KROB; Ada Suk-Fung NG

    2005-01-01

    This paper presents a generic mathematical model for depicting the diffusion of an innovative product on a given market. Our approach relies on a probabilistic modeling of each customer behavior with respect to the commercial process which is used to promote such a product. We introduce in particular the concept of coherent market that corresponds to a market which can be analyzed in a uniform way within our model. This last notion allows us to recover the classical empirical results that were discovered and widely studied by E.M. Rogers and his school. We explain finally how to use our approach as a support for analytic predictive marketing.

  17. Changes in ruminal volatile fatty acid production and absorption rate during the dry period and early lactation as affected by rate of increase of concentrate allowance.

    Dieho, K; Dijkstra, J; Schonewille, J T; Bannink, A

    2016-07-01

    The aim of the present experiment was to study changes in volatile fatty acid (VFA) production using an isotope dilution technique, and changes in VFA fractional absorption rate (kaVFA) using a buffer incubation technique (BIT) during the dry period and early lactation, as affected by the postpartum (pp) rate of increase of concentrate allowance. The current results are complementary to previously reported changes on rumen papillae morphology from the same experiment. From 50 d antepartum to 80 d pp, VFA production rate was measured 5 times and kaVFA was measured 10 times in 12 rumen-cannulated Holstein Friesian cows. Cows had free access to a mixed ration, consisting of grass and corn silage, soybean meal, and (dry period only) chopped straw. Treatment consisted of either a rapid (RAP; 1.0 kg of DM/d; n=6) or gradual (GRAD; 0.25 kg of DM/d; n=6) increase of concentrate allowance (up to 10.9 kg of DM/d), starting at 4 d pp, aimed at creating a contrast in rumen-fermentable organic matter intake. For the BIT, rumen contents were evacuated, the rumen washed, and a standardized buffer fluid introduced [120 mM VFA, 60% acetic (Ac), 25% propionic (Pr), and 15% butyric (Bu) acid; pH 5.9 and Co-EDTA as fluid passage marker]. For the isotope dilution technique, a pulse-dose of (13)C-labeled Ac, Pr, and Bu and Co-EDTA as fluid passage marker was infused. The rate of total VFA production was similar between treatments and was 2 times higher during the lactation (114 mol/d) than the dry period (53 mol/d). Although papillae surface area at 16, 30, and 44 d pp was greater in RAP than GRAD, Bu and Ac production at these days did not differ between RAP and GRAD, whereas at 16 d pp RAP produced more Pr than GRAD. These results provide little support for the particular proliferative effects of Bu on papillae surface area. Similar to developments in papillae surface area in the dry period and early lactation, the kaVFA (per hour), measured using the BIT, decreased from 0.45 (Ac), 0

  18. The Influence of Photolysis Rate Constants in Ozone Production for the Paso del Norte Region

    Becerra, Fernando; Fitzgerald, Rosa

    2012-03-01

    In this research work we are focusing on understanding the relationship between photolysis rates and the photochemical ozone changes observed in the Paso del Norte region. The city of El Paso, Texas together with Ciudad Juarez, Mexico, forms the largest contiguous bi-national metropolitan area. This region suffers year-round ozone pollution events, and a better understanding is needed to mitigate them. Previous studies have found that ambient ozone concentrations tend to be higher on weekends rather than on weekdays, this phenomenon being referred to, as the ``weekend effect.'' If the ozone standard is exceeded more frequently on weekends, then this phenomenon must be considered in the design of ozone control strategies. In this work we investigate some of the most representative weekend ozone episodes at El Paso, TX, during the years 2009, 2010 and 2011 using the ozone photolysis rates. In this research the TUV radiative-transfer model is used to calculate the local photolysis rates and a UV MFRSR instrument is used to obtain experimental parameters. Seasonal variations and the weekday-weekend effect is studied. The results of this research will help to understand the underlying behavior of the photolysis rate constants when different atmospheric conditions are present.

  19. Rental prices, rates of return, capital aggregation and productivity : Evidence from EU and US

    Erumban, 27675

    2008-01-01

    With the increasing importance of investment in information and communication technology, methods for measuring the contribution of capital to growth have re-assumed centre-stage in recent growth accounting literature. The importance of using capital service growth rates rather than capital stock gr

  20. Tax evasion, human capital, and productivity-induced tax rate reduction

    Gillman, Max; Kejak, Michal

    2014-01-01

    Roč. 8, č. 1 (2014), s. 42-79. ISSN 1932-8575 R&D Projects: GA ČR GA13-34096S Institutional support: RVO:67985998 Keywords : tax evasion * human capital * tax rates and tables Subject RIV: AH - Economics Impact factor: 0.600, year: 2014

  1. Tax evasion, human capital, and productivity-induced tax rate reduction

    Gillman, M.; Kejak, Michal

    2014-01-01

    Roč. 8, č. 1 (2014), s. 42-79. ISSN 1932-8575 Grant ostatní: UK(CZ) UNCE 204005/2012 Institutional support: PRVOUK-P23 Keywords : tax evasion * human capital * tax rates and tables Subject RIV: AH - Economics Impact factor: 0.600, year: 2014

  2. Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate

    Wang, Qilin; Sun, Jing; Zhang, Chang; Xie, Guo-Jun; Zhou, Xu; Qian, Jin; Yang, Guojing; Zeng, Guangming; Liu, Yiqi; Wang, Dongbo

    2016-01-01

    Anaerobic sludge digestion is the main technology for sludge reduction and stabilization prior to sludge disposal. Nevertheless, methane production from anaerobic digestion of waste activated sludge (WAS) is often restricted by the poor biochemical methane potential and slow hydrolysis rate of WAS. This work systematically investigated the effect of PHA levels of WAS on anaerobic methane production, using both experimental and mathematical modeling approaches. Biochemical methane potential tests showed that methane production increased with increased PHA levels in WAS. Model-based analysis suggested that the PHA-based method enhanced methane production by improving biochemical methane potential of WAS, with the highest enhancement being around 40% (from 192 to 274 L CH4/kg VS added; VS: volatile solid) when the PHA levels increased from 21 to 143 mg/g VS. In contrast, the hydrolysis rate (approximately 0.10 d-1) was not significantly affected by the PHA levels. Economic analysis suggested that the PHA-based method could save $1.2/PE/y (PE: population equivalent) in a typical wastewater treatment plant (WWTP). The PHA-based method can be easily integrated into the current WWTP to enhance methane production, thereby providing a strong support to the on-going paradigm shift in wastewater management from pollutant removal to resource recovery.

  3. Blastocyst rate of in vitro embryo production in sheep is affected by season.

    Mara, L; Sanna, D; Casu, S; Dattena, M; Muñoz, I M Mayorga

    2014-08-01

    It has been reported that the number and quality of in vitro produced embryos is season related. This study was conducted to assess the effect of season on cleavage, blastocyst and lambing rates of in vitro produced ovine embryos during 3 years of collection data. Ovaries of Sarda sheep were collected from a slaughterhouse. In total, 5035 oocytes were recovered and matured in TCM-199 with 4 mg/ml bovine serum albumin (BSA), 100 μM cysteamine, 0.3 mM Na pyruvate, 0.1 UI/ml recombinant follicle-stimulating hormone (r-FSH), 0.1 UI/ml recombinant luteinising hormone (r-LH), and 1 μg/ml estradiol-17β. Matured oocytes were fertilized with fresh semen in synthetic oviductal fluid (SOF) with 20% heat inactivated estrous sheep serum. The presumptive zygotes were cultured for 6-7 days (blastocyst stage) in SOF medium supplemented with 1% Basel Medium Eagle (BME), 1% Minimum Essential Medium, 1 mM glutamine and 8 mg/ml fatty acid-free BSA. The embryos produced were vitrified and a total of 165 blastocysts (80 from the breeding season and 85 from the anoestrous season) were transferred in pairs into recipient ewes during the reproductive period. There were no significant differences in cleavage rates between seasons in any of the 3 years examined (84% versus 83%, 81% versus 80% and 80% versus 79%, respectively). The blastocyst rate varied significantly between seasons in 2005 and 2007 (P < 0.05), and in 2006 (P < 0.001). There were no differences in pregnancy and lambing rates between embryos during anoestrous versus during the breeding season. In conclusion, only the blastocyst rate appeared to have been affected by season, possibly due to variation in the number of developmentally competent oocytes. PMID:23458093

  4. Setting the holding cost rates in a multi-product system with remanufacturing

    U. Corbacı oğ lu; E.A. van der Laan (Erwin)

    2005-01-01

    textabstractThe Net Present Value (NPV) approach is considered to be the right approach to study inventory and production systems. But, approximate average cost (AC) approach is widely used in both practice and theory. However, the opportunity cost interpretation of AC framework is not that straight

  5. 76 FR 75661 - Change in Rates and Classes of General Applicability for Competitive Products

    2011-12-02

    ... within this price category. Finally, in January 2012, the Intelligent Mail Package Barcode (IMpb) will..., and Package Services, will have new ``Return Service'' branding. E. Commercial First-Class Package... will be renamed Commercial First- Class Package Service. This product is positioned as a...

  6. Institutional Productivity Ratings and Publishing Trends in Nine Literacy Journals: 1972-2012

    Rosborough, Alessandro; Miner, Amy Baird; Wilcox, Brad; Morrison, Timothy G.

    2015-01-01

    This study examined the productivity of faculty members who published in nine leading literacy professional journals from 1972-2012. Those universities with the greatest number of articles written by literacy faculty members are listed. This listing was also adjusted according to number of literacy faculty members at each institution, resulting in…

  7. In Situ Measurement of Local Hydrogen Production Rate by Bubble-Evolved Recording

    Xiaowei Hu; Liejin Guo; Yechun Wang

    2013-01-01

    Hydrogen visibly bubbles during photocatalytic water splitting under illumination with above-bandgap radiation, which provides a direct measurement of local gas-evolving reaction rate. In this paper, optical microscopy of superfield depth was used for recording the hydrogen bubble growth on Cd0.5Zn0.5S photocatalyst in reaction liquid and illuminated with purple light. By analyzing change of hydrogen bubble size as a function of time, we understood that hydrogen bubble growth experienced two ...

  8. The devil you know: The effect of brand recognition and product ratings on consumer choice

    Volker Thoma

    2013-01-01

    Full Text Available Previous research on the role of recognition in decision-making in inferential choice has focussed on the Recognition Heuristic (RH, which proposes that in situations where recognition is predictive of a decision criterion, recognized objects will be chosen over unrecognized ones, regardless of any other available relevant information. In the current study we examine the role of recognition in preferential choice, in which subjects had to choose one of a pair of consumer objects that were presented with quality ratings (positive, neutral, and negative. The results showed that subjects' choices were largely based on recognition, as the famous brand was preferred even when additional star ratings rendered it as less attractive. However, the additional information did affect the proportion of chosen famous items, in particular in the cases when star ratings for the recognised brand were negative. This condition also resulted in longer response times compared to neutral and positive conditions. Thus, the current data do not point to a simple compensatory mechanism in preferential choice: although choice is affected by additional information, it seems that recognition is employed as an initial important first step in the decision-making process.

  9. When Does Variable Rate Technology for Agricultural Sprayers Pay? A Case Study for Cotton Production in Tennessee

    Mooney, Daniel; Larson, James; Roberts, Roland; English, Burton

    2009-01-01

    Producers interested in precision agriculture lack information on the profitability of variable rate technology (VRT) systems for agricultural sprayers. A partial budgeting framework was developed to evaluate the level of input savings required to pay for investments in VRT. To illustrate this framework, a case study for cotton production in Tennessee is provided. Ownership and information costs were determined for two commerciallyavailable VRT systems and compared to extension recommended in...

  10. Size-fractionated characterization and quantification of nanoparticle release rates from a consumer spray product containing engineered nanoparticles

    Hagendorfer, Harald; Lorenz, Christiane; Kaegi, Ralf; Sinnet, Brian; Gehrig, Robert; Goetz, Natalie V.; Scheringer, Martin; Ludwig, Christian; Ulrich, Andrea

    2010-01-01

    This study describes methods developed for reliable quantification of size- and element-specific release of engineered nanoparticles (ENP) from consumer spray products. A modified glove box setup was designed to allow controlled spray experiments in a particle-minimized environment. Time dependence of the particle size distribution in a size range of 10-500 nm and ENP release rates were studied using a scanning mobility particle sizer (SMPS). In parallel, the aerosol was transferred to a size...

  11. Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability

    Pietro Randelli; Alessandra Menon; Vincenza Ragone; Pasquale Creo; Sonia Bergante; Filippo Randelli; Laura De Girolamo; Umberto Alfieri Montrasio; Giuseppe Banfi; Paolo Cabitza; Guido Tettamanti; Luigi Anastasia

    2016-01-01

    Increasing the success rate of rotator cuff healing remains tremendous challenge. Among many approaches, the possibility of activating resident stem cells in situ, without the need to isolate them from biopsies, could represent valuable therapeutic strategy. Along this line, it has been recently demonstrated that lipoaspirate product, Lipogems, contains and produces growth-factors that may activate resident stem cells. In this study, human tendon stem cells (hTSCs) from the rotator cuff were ...

  12. Piece rates and learning: understanding work and production in the New England textile industry a century ago.

    Leunig, Tim

    2003-01-01

    New data on individual worker’s outputs show that New England ring spinners exhibited substantial on the job learning c. 1905. Despite this, variable capital-labour ratios meant high labour turnover reduced aggregate labour productivity only fractionally. The combination of variable capital-labour ratios and piece rates meant low average experience levels did not raise unit costs. This made firms willing to hire all comers, so immigrants readily found work. Equally firms were indifferent to l...

  13. The Optimal Replenishment Policy under Trade Credit Financing with Ramp Type Demand and Demand Dependent Production Rate

    Juanjuan Qin; Weihua Liu

    2014-01-01

    This paper investigates the optimal replenishment policy for the retailer with the ramp type demand and demand dependent production rate involving the trade credit financing, which is not reported in the literatures. First, the two inventory models are developed under the above situation. Second, the algorithms are given to optimize the replenishment cycle time and the order quantity for the retailer. Finally, the numerical examples are carried out to illustrate the optimal solutions and the ...

  14. An Inventory System for Deteriorating Products with Ramp-Type Demand Rate under Two-Level Trade Credit Financing

    K. Skouri; Darzanou, G.

    2011-01-01

    An inventory system for deteriorating products, with ramp-type demand rate, under two-level trade credit policy is considered. Shortages are allowed and partially backlogged. Sufficient conditions of the existence and uniqueness of the optimal replenishment policy are provided, and an algorithm, for its determination, is proposed. Numerical examples highlight the obtained results, and sensitivity analysis of the optimal solution with respect to major parameters of the system is carried out.

  15. Development of a new product for unrestrained heart rate measurement in swimming: a user centered design approach

    Van Rooijen, V.; De Voogd-Claessen, L.; Lauche, K.; Jeanne, V.; Van der Vliet, R.

    2010-01-01

    This paper reports the development of a new product for unrestrained heart rate measurement to provide feedback and target training efforts in professional swimming. While training is considered to be the key to becoming a top athlete, little is known about how to determine the right training course for individual athletes (Maase, 2009, ). In order to optimize the training load of an individual athlete, coaches need to monitor physiological indicators that are linked to performance. Interview...

  16. Measurement of HO{sub x}{center_dot} production rate due to radon decay in air

    Ding, Huiling

    1993-08-01

    Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce ({center_dot}OH and HO{sub 2} {center_dot}) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HO{sub x}{center_dot} production rate in indoor air caused by radon decay. Average HO{sub x}{center_dot} production rate was found to be (4.31{plus_minus}0.07) {times} 10{sup 5} HO{sub x}{center_dot} per Rn decay per second (Bq) 3.4 to 55.0% at 22C. This work provided G{sub (HO{sub x}{center_dot})}-value, 7.86{plus_minus}0.13 No./100 eV in air by directly measuring [HO{sub x}{center_dot}] formed from the radiolysis procedure. This G value implies that HO{sub x}{center_dot} produced by radon decay in air might be formed by multiple processes and may be result of positive ion-molecule reactions, primary radiolysis, and radical reactions. There is no obvious relation between HO{sub x}{center_dot} production rate and relative humidity. A laser-induced fluorescence (LIF) system has been used for {center_dot}OH production rate measurement; it consists of an excimer laser, a dye laser, a frequency doubler, a gaseous fluorescence chamber, and other optical and electronic parts. This system needs to be improved to eliminate the interferences of light scattering and artificial {center_dot}OH produced from the photolysis of O{sub 3}/H{sub 2}O.

  17. Seasonal rates of benthic primary production in a Greenland fjord measured by aquatic eddy correlation

    M. Attard, Karl; Glud, Ronnie; McGinnis, Daniel F.;

    2014-01-01

    We present the first year-round estimates of benthic primary production at four contrasting shallow (3–22 m depth) benthic habitats in a southwest Greenland fjord. In situ measurements were performed using the noninvasive aquatic eddy-correlation (EC) oxygen (O2) flux method. A series of high-qua...... document the importance of benthic photosynthesis on an ecosystem level and indicate that the benthic phototrophic compartment should be accounted for when assessing carbon and nutrient budgets as well as responses of coastal Arctic ecosystems to climate change.......-quality multiple-day EC data sets document the presence of a year-round productive benthic phototrophic community. The shallow-water sites were on average autotrophic during the spring and summer months, up to 43.6 mmol O2 m22 d21, and heterotrophic or close to metabolic balance during the autumn and winter...

  18. Calculation of production rates and thick-target yields for platinum isotopes prepared at the cyclotron

    The production of l91Pt and l88Pt by cyclotron irradiation can be carried out by direct reactions using α and proton beams on osmium and iridium targets respectively. The lack of data in the literature concerning the excitation functions for these nuclear reactions makes the optimization of the irradiation parameters impossible. This report includes a review of the few nuclear data available in the literature, some theoretical predictions about the beam energy necessary for the production of the two radioisotopes of interest and the results of some preliminary irradiations carried out with the variable energy cyclotron of JRC-Ispra (VA, Italy) of the EU at three different energies: 35 MeV for protons, 22 and 33 MeV for α particles

  19. Determination of INDOT Highway Construction Production Rates and Estimation of Contract Times

    Jiang, Yi; Wu, Hongbo

    2004-01-01

    The duration of a highway construction project depends primarily on the quantity or magnitude of the construction work and the productivity of the construction crew. In addition, many other factors may also affect the construction duration, such as the type of construction, traffic features, location (urban or rural site), and weather conditions. When a state highway construction project contract is bid, a reasonable time must set and specified in the contract documents for completion of the ...

  20. Species Production and Heat Release Rates in Two-Layered Natural Gas Fires

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

    1991-01-01

    A fire burning in an enclosure with restricted ventilation will result in the accumulation of a layer of warm products of combustion mixed with entrained air adjacent to the ceiling. For many conditions, the depth of this layer will extend to occupy a significant fraction of the volume of the room. Eventually, the interface between this vitiated ceiling layer and the uncontaminated environment below will position itself so that a large portion of the combustion processes occur in this vitiate...

  1. Product Backlog Rating: A Case Study On Measuring Test Quality In Scrum

    Kayes, Imrul; Sarker, Mithun; Chakareski, Jacob

    2013-01-01

    Agile software development methodologies focus on software projects which are behind schedule or highly likely to have a problematic development phase. In the last decade, Agile methods have transformed from cult techniques to mainstream methodologies. Scrum, an Agile software development method, has been widely adopted due to its adaptive nature. This paper presents a metric that measures the quality of the testing process in a Scrum process. As product quality and process quality correlate,...

  2. The effect of consumer ratings and attentional allocation on product valuations

    Ashby, Nathaniel J. S.; Lukasz Walasek; Andreas Glöckner

    2015-01-01

    Online marketplaces allow consumers to leave reviews about the products they purchase, which are visible to potential customers and competitors. While the impact of reviews on valuations of worth and purchasing decisions has been intensively studied, little is known about how the reviews themselves are attended to, and the relation between attention and valuations. In three studies we use eye-tracking methodologies to investigate attention in subjective monetary valuations o...

  3. Using short pulses to enhance the production rate of vibrationally excited hydrogen molecules in hydrogen discharge

    Sun Ji-Zhong; Li Xian-Tao; Bai Jing; Wang De-Zhen

    2012-01-01

    Hydrogen discharges driven by the combined radio-frequency(rf)/short pulse sources are investigated using the particle-in-cell method.The simulation results show that the discharge driven additionally by the short pulse can enhance the electron density and modulate the electron energy to provide a better condition for negative hydrogen ion production than the discharge driven by the rf-only source.

  4. Aquaponics: integrating fish feeding rates and ion waste production for strawberry hydroponics

    Aquaponics is the science of integrating intensive fish aquaculture with plant production in recirculating water systems. Although ion waste production by f ish cannot satisfy all plant requirements, less is known about the relationship between total feed provided for f ish and the production of milliequivalents (mEq) of different macronutrients for plants, especially for nutrient flow hydroponics used for strawberry production in Spain. That knowledge is essential to consider the amount of macronutrients available in aquaculture systems so that farmers can estimate how much nutrient needs to be supplemented in the waste water from fish, to produce viable plant growth. In the present experiment, tilapia (Oreochromis niloticus L.) were grown in a small-scale recirculating system at two different densities while growth and feed consumption were noted every week for five weeks. At the same time points, water samples were taken to measure pH, EC25, HCO3-, Cl-, NH+4, NO2-, NO3-, H2PO4-, SO42-, Na+, K+, Ca2+ and Mg2+ build up. The total increase in mEq of each ion per kg of feed provided to the fish was highest for NO3-, followed, in decreasing order, by Ca2+, H2PO4-, K+, Mg2+ and SO42-. The total amount of feed required per mEq ranged from 1.61- 13.1 kg for the four most abundant ions (NO3-, Ca2+, H2PO4- and K+) at a density of 2 kg fish m3, suggesting that it would be rather easy to maintain small populations of fish to reduce the cost of hydroponic solution supplementation for strawberries. (Author) 16 refs.

  5. Estimating the carbon sequestration capacity of shale formations using methane production rates.

    Tao, Zhiyuan; Clarens, Andres

    2013-10-01

    Hydraulically fractured shale formations are being developed widely for oil and gas production. They could also represent an attractive repository for permanent geologic carbon sequestration. Shales have a low permeability, but they can adsorb an appreciable amount of CO2 on fracture surfaces. Here, a computational method is proposed for estimating the CO2 sequestration capacity of a fractured shale formation and it is applied to the Marcellus shale in the eastern United States. The model is based on historical and projected CH4 production along with published data and models for CH4/CO2 sorption equilibria and kinetics. The results suggest that the Marcellus shale alone could store between 10.4 and 18.4 Gt of CO2 between now and 2030, which represents more than 50% of total U.S. CO2 emissions from stationary sources over the same period. Other shale formations with comparable pressure-temperature conditions, such as Haynesville and Barnett, could provide significant additional storage capacity. The mass transfer kinetic results indicate that injection of CO2 would proceed several times faster than production of CH4. Additional considerations not included in this model could either reinforce (e.g., leveraging of existing extraction and monitoring infrastructure) or undermine (e.g., leakage or seismicity potential) this approach, but the sequestration capacity estimated here supports continued exploration into this pathway for producing carbon neutral energy. PMID:23988277

  6. Effect of stocking rate on milk and pasture productivity and supplementary feed use for spring calving pasture fed dairy systems.

    Patton, D; Pierce, K M; Horan, B

    2016-07-01

    The productivity of grazing systems is primarily limited by the scale and efficiency of systems applied to the grazable land platform adjacent to the milking parlor. The objective of this study was to compare forage production, utilization and quality, milk production, and requirement for supplementary feeds for 2 different grazing platform stocking rate (GPSR) treatments over 4 yr. Animals were randomly allocated to 1 of 2 GPSR treatments: high-closed (HC; 3.1 cows/ha) and high-open (HO; 4.5 cows/ha), which were designed to represent alternative GPSR in a post-European Union milk quota, spring calving, pasture-based milk production system. Animal production data were analyzed using Proc MIXED of SAS with GPSR, year, and parity included as fixed effects in the final model. Within a seasonal spring calving grazing system, at high GPSR and offering moderate amounts of additional supplements based on pasture supply deficits, both systems produced more milk and fat plus protein per hectare in comparison with Irish commercial dairy farms. Although requiring additional supplementation, increased GPSR resulted in increased milk production per hectare but also in an increased requirement for concentrate and forage supplementation during lactation. No significant influence of GPSR was found on body weight and body condition score or reproductive performance during the 4-yr study period. In addition, GPSR also had no effect on pasture production, utilization, or quality during the study period. The strategic use of additional supplements with restricted pasture availability at higher GPSR maintained milk production per cow and significantly increased milk production per hectare. PMID:27108176

  7. Dynamic Linkages between Denitrification Functional Genes/Enzymes and Biogeochemical Reaction Rates of Nitrate and Its Reduction Products

    Li, M.; Shi, L.; Qian, W.; Gao, Y.; Liu, Y.; Liu, C.

    2015-12-01

    Denitrification is a respiratory process in which oxidized nitrogen compounds are used as alternative electron acceptors for energy production when oxygen is limited. Denitrification is an important process that not only accounts for the significant loss of nitrogen fertilizers from soils but also leads to NO, N2O and CO2 emissions, which are important greenhouse gas species. In this study, denitrification was investigated in Columbia River sediments, focusing on the dynamic linkages between functional genes/enzymes and biogeochemical reaction rates of nitrate and its reduction products. NO3-, NO2- and N2O were assayed in different incubation time. DNA was extracted from the sediments and functional genes were quantified as a function of time during the denitrification. Functional enzymes were extracted from the sediments and measured using a newly developed, targeted protein method. The biogeochemical, functional gene, and enzyme data were collectively used to establish the dynamic correlation of functional genes/enzymes and biogeochemical reaction rates. The results provide fundamental insights regarding the dynamic regulation of functional genes and enzymes in the processes of denitrification and greenhouse gas production, and also provide experimental data critical for the development of biogeochemical reaction models that incorporate genome-scale insights and describe macroscopic biogeochemical reaction rates in ecosystems.

  8. Sensitive in situ method to measure the rate of neutral free radical production by photodeionization of negative ion beams

    Photoelectron-current measurement by low-frequency electromodulation probe (PMMP) is proposed as a sensitive method to determine the rate Gr of neutral free radical production by the photodeionization of negative ion beams (PDINIB). The PMMP method was employed to evaluate the production rate in a trial surface-processing apparatus developed in the author's laboratory utilizing a steady-flux refined beam of neutral free radicals produced by the PDINIB procedure. A 63Cu- negative ion beam of kinetic energy Ei varied up to 15 keV was irradiated with a 514.5 nm visible light beam from a 25 W cw Ar+ ion laser. The detection limit of the production rate by the measurement setup was 6x109/s under the conditions that Ei=15 keV, the negative ion beam current Ii=4 μA, and the laser power P=6 W. Based on the results of these basic experiments, furthermore, the photodeionization efficiency defined by eGr/Ii where e is the elementary electric charge was estimated to be 27±6% under the conditions that Ei=15 keV, Ii=40 μA, and P=18 W

  9. Relative rates of nitric oxide and nitrous oxide production by nitrifiers, denitrifiers, and nitrate respirers.

    Anderson, I C; Levine, J S

    1986-05-01

    Biogenic emissions of nitric and nitrous oxides have important impacts on the photochemistry and chemistry of the atmosphere. Although biogenic production appears to be the overwhelming source of N(2)O, the magnitude of the biogenic emission of NO is very uncertain. In soils, possible sources of NO and N(2)O include nitrification by autotrophic and heterotrophic nitrifiers, denitrification by nitrifiers and denitrifiers, nitrate respiration by fermenters, and chemodenitrification. The availability of oxygen determines to a large extent the relative activities of these various groups of organisms. To better understand this influence, we investigated the effect of the partial pressure of oxygen (pO(2)) on the production of NO and N(2)O by a wide variety of common soil nitrifying, denitrifying, and nitrate-respiring bacteria under laboratory conditions. The production of NO per cell was highest by autotrophic nitrifiers and was independent of pO(2) in the range tested (0.5 to 10%), whereas N(2)O production was inversely proportional to pO(2). Nitrous oxide production was highest in the denitrifier Pseudomonas fluorescens, but only under anaerobic conditions. The molar ratio of NO/N(2)O produced was usually greater than unity for nitrifiers and much less than unity for denitrifiers. Chemodenitrification was the major source of both the NO and N(2)O produced by the nitrate respirer Serratia marcescens. Chemodenitrification was also a possible source of NO and N(2)O in nitrifier cultures but only when high concentrations of nitrite had accumulated or were added to the medium. Although most of the denitrifiers produced NO and N(2)O only under anaerobic conditions, chemostat cultures of Alcaligenes faecalis continued to emit these gases even when the cultures were sparged with air. Based upon these results, we predict that aerobic soils are primary sources of NO and that N(2)O is produced only when there is sufficient soil moisture to provide the anaerobic microsites

  10. Production, chemical composition and stocking rate of forage systems compounds for coastcross-1 intercropped with ryegrass and clovers

    Michelle Schalemberg Diehl

    2014-10-01

    Full Text Available The objective of this research was to evaluate the forage production, crude protein and neutral detergent fiber level, stocking rate of three forage systems compounds for Coastcross-1 (Cynodon dactylon L. Pers. + ryegrass (Lolium multiflorum Lam., cv. Comum; Coastcross-1 + ryegrass + red clover (Trifolium pratense L., cv. Estanzuela 116 and Coastcross-1 + ryegrass + white clover (Trifolium repens L., cv. Yi. The experiment was carried out from April 2007 to April 2008, for 11 grazing cycles, six in winter season and five in summer season. Holstein cows receiving 0.9% of body weight/day feed supplement concentrate were used. The herbage mass of pre and post-grazing, botanical and morphological composition crude protein and neutral detergent fiber level were evaluated. A randomized complete design was used with three treatments (forage systems two replications (paddocks and independent evaluations (grazing cycles. Superior value (P<0.05 of forage production and daily dry matter accumulation rate were found in winter season for the forage systems with legume. No differences in dry matter disappearance rate and stocking rate averages were detected among pastures. Residual effects of red clover were observed on Coastcross-1 + ryegrass with superior result (P<0.05 on crude protein and lower neutral detergent fiber level.

  11. Rate of escape of random walks on wreath products and related groups

    Revelle, David

    2003-01-01

    This article examines the rate of escape for a random walk on $G\\wr \\Z$ and proves laws of the iterated logarithm for both the inner and outer radius of escape. The class of G for which these results hold includes finite, G as well as groups of the form $H\\wr \\Z$, so the construction can be iterated. Laws of the iterated logarithm are also found for random walk on Baumslag--Solitar groups and a discrete version of the Sol geometry.

  12. Optimisation of fertiliser rates in crop production against energy use indicators

    Rossner, Helis; Ritz, Christian; Astover, Alar

    2014-01-01

    parame-ters exemplary data for spring-wheat in boreal climate condition in Estonia in 2006–2010. The effect ofmineral N with rates 0, 40, 80, 120 and 160 kg N ha−1was studied on the background of composted cowmanure and without organic fertilisers. Univalent parameters, energy gain (EG) (energy output...... − energyinput) and energy ratio (ER) (energy output/energy input) were calculated. To aggregate parameterswith different units (ER and EG) we proposed two standardisation approaches for combined indices. ERmaximisation gave both organic fertilisation background optimum N norms significantly lower than EG(p < 0...

  13. Evaluation of processing rate and reaction products in the polymeric material furnace using the molten slag

    A prototype furnace, which adopted the new technique for combusting the polymeric material, was manufactured. In this furnace, the polymeric materials such as rubber were fed to molten slag. The ash, generated at the surface of the polymeric material, dissolved into melt, which promoted the surface combustion of the fixed carbon. The advantages of the new furnace are: (1) High treating rate was realized at so low air excessive ratio as 0.5 ∼ 0.7. (2) The fineness of the unburned particles made the combustion in the after burner easy. (3) The reduction of flying ash coming from the gasification zone lowered the load of the ceramic filters. (author)

  14. Mass production of graphene nanoscrolls and their application in high rate performance supercapacitors

    Zheng, Bingna; Xu, Zhen; Gao, Chao

    2016-01-01

    The output of graphene nanoscrolls (GNSs) has been greatly enhanced to the gram-level by using an improved spray-freeze-drying method without damaging the high transforming efficiency (>92%). The lowest bulk density of GNS foam reaches 0.10 mg cm-3. Due to the unique morphology and high specific surface area (386.4 m2 g-1), the specific capacitances of the GNSs (90-100 F g-1 at 1 A g-1) are all superior to those of multiwalled carbon nanotubes meanwhile maintaining excellent rate capabilities (60-80% retention at 50 A g-1). For the first time, all-graphene-based films (AGFs) are fabricated via the intercalation of GNSs into graphene layers. The AGF exhibits a capacitance of 166.8 F g-1 at 1 A g-1 and rate capability (83.9% retention at 50 A g-1) better than those of pure reduced graphene oxide (RGO) films and carbon nanotubes/graphene hybrid films (CGFs).The output of graphene nanoscrolls (GNSs) has been greatly enhanced to the gram-level by using an improved spray-freeze-drying method without damaging the high transforming efficiency (>92%). The lowest bulk density of GNS foam reaches 0.10 mg cm-3. Due to the unique morphology and high specific surface area (386.4 m2 g-1), the specific capacitances of the GNSs (90-100 F g-1 at 1 A g-1) are all superior to those of multiwalled carbon nanotubes meanwhile maintaining excellent rate capabilities (60-80% retention at 50 A g-1). For the first time, all-graphene-based films (AGFs) are fabricated via the intercalation of GNSs into graphene layers. The AGF exhibits a capacitance of 166.8 F g-1 at 1 A g-1 and rate capability (83.9% retention at 50 A g-1) better than those of pure reduced graphene oxide (RGO) films and carbon nanotubes/graphene hybrid films (CGFs). Electronic supplementary information (ESI) available: SEM image for GNS transformation efficiency assessment, images for GNS density modeling and calculation, tables for GNS specific capacitance and retention, figures and tables for AGF, CGF and RGO

  15. A unique micromechanocalorimeter for simultaneous measurement of heat rate and force production of cardiac trabeculae carneae.

    Han, June-Chiew; Taberner, Andrew J; Kirton, Robert S; Nielsen, Poul M; Smith, Nicholas P; Loiselle, Denis S

    2009-09-01

    To study cardiac muscle energetics quantitatively, it is of paramount importance to measure, simultaneously, mechanical and thermal performance. Ideally, this should be achieved under conditions that minimize the risk of tissue anoxia, especially under high rates of energy expenditure. In vitro, this consideration necessitates the use of preparations of small radial dimensions. To that end, we have constructed a unique micromechanocalorimeter, consisting of an open-ended flow-through microcalorimeter, a force transducer, and a pair of muscle-length actuators. The device enables the metabolic and mechanical performance of cardiac trabeculae carneae to be investigated for prolonged periods in a continuously replenished oxygen- and nutrient-rich environment. PMID:19589958

  16. An EPLS model for a variable production rate with stock-price sensitive demand and deterioration

    Roy T; Chaudhuri K.S.

    2012-01-01

    It is observed that large piles of consumer goods displayed in supermarkets lead consumers to buy more, which generates more profit to sellers. But a large number of on-hand display of stock leaves a negative impression on the buyer. Also, the amount of shelf or display space is limited. Due to this reason, we impose a restriction on the number of on-hand display of stock and also on initial and ending on-hand stock levels. We introduce an economic production lot size model, where produ...

  17. HCRS: A hybrid clothes recommender system based on user ratings and product features

    Hu, Xiaosong; Zhu, Wen; Li, Qing

    2014-01-01

    Nowadays, online clothes-selling business has become popular and extremely attractive because of its convenience and cheap-and-fine price. Good examples of these successful Web sites include Yintai.com, Vancl.com and Shop.vipshop.com which provide thousands of clothes for online shoppers. The challenge for online shoppers lies on how to find a good product from lots of options. In this article, we propose a collaborative clothes recommender for easy shopping. One of the unique features of thi...

  18. A New Process for Hot Metal Production at Low Fuel Rate - Phase 1 Feasibility Study

    Dr. Wei-Kao Lu

    2006-02-01

    The project is part of the continuing effort by the North American steel industry to develop a coal-based, cokeless process for hot metal production. The objective of Phase 1 is to determine the feasibility of designing and constructing a pilot scale facility with the capacity of 42,000 mtpy of direct reduced iron (DRI) with 95% metallization. The primary effort is performed by Bricmont, Inc., an international engineering firm, under the supervision of McMaster University. The study focused on the Paired Straight Hearth furnace concept developed previously by McMaster University, The American Iron and Steel Institute and the US Department of Energy.

  19. Aquaponics: integrating fish feeding rates and ion waste production for strawberry hydroponics

    Villarroel, M.; Alvarino, J. M. R.; Duran, J. M.

    2011-07-01

    Aquaponics is the science of integrating intensive fish aquaculture with plant production in recirculating water systems. Although ion waste production by fish cannot satisfy all plant requirements, less is known about the relationship between total feed provided for fish and the production of milliequivalents (mEq) of different macronutrients for plants, especially for nutrient flow hydroponics used for strawberry production in Spain. That knowledge is essential to consider the amount of macronutrients available in aquaculture systems so that farmers can estimate how much nutrient needs to be supplemented in the waste water from fish, to produce viable plant growth. In the present experiment, tilapia (Oreochromis niloticus L.) were grown in a small-scale recirculating system at two different densities while growth and feed consumption were noted every week for five weeks. At the same time points, water samples were taken to measure pH, EC25, HCO3{sup -}, Cl{sup -}, NH{sup +}{sub 4}, NO{sub 2}{sup -}, NO{sub 3}{sup -}, H{sub 2}PO{sub 4}{sup -}, SO{sub 4}{sup 2}-, Na{sup +}, K{sup +}, Ca{sup 2}+ and Mg{sup 2}+ build up. The total increase in mEq of each ion per kg of feed provided to the fish was highest for NO{sub 3}{sup -}, followed, in decreasing order, by Ca{sup 2}+, H{sub 2}PO{sub 4}{sup -}, K{sup +}, Mg{sup 2}+ and SO{sub 4}{sup 2}-. The total amount of feed required per mEq ranged from 1.61 - 13.1 kg for the four most abundant ions (NO{sub 3}{sup -}, Ca{sup 2}+, H{sub 2}PO{sub 4}{sup -} and K{sup +}) at a density of 2 kg fish m{sup -3}, suggesting that it would be rather easy to maintain small populations of fish to reduce the cost of hydroponic solution supplementation for strawberries. (Author) 16 refs.

  20. Cued Speech Transliteration: Effects of Speaking Rate and Lag Time on Production Accuracy.

    Krause, Jean C; Tessler, Morgan P

    2016-10-01

    Many deaf and hard-of-hearing children rely on interpreters to access classroom communication. Although the exact level of access provided by interpreters in these settings is unknown, it is likely to depend heavily on interpreter accuracy (portion of message correctly produced by the interpreter) and the factors that govern interpreter accuracy. In this study, the accuracy of 12 Cued Speech (CS) transliterators with varying degrees of experience was examined at three different speaking rates (slow, normal, fast). Accuracy was measured with a high-resolution, objective metric in order to facilitate quantitative analyses of the effect of each factor on accuracy. Results showed that speaking rate had a large negative effect on accuracy, caused primarily by an increase in omitted cues, whereas the effect of lag time on accuracy, also negative, was quite small and explained just 3% of the variance. Increased experience level was generally associated with increased accuracy; however, high levels of experience did not guarantee high levels of accuracy. Finally, the overall accuracy of the 12 transliterators, 54% on average across all three factors, was low enough to raise serious concerns about the quality of CS transliteration services that (at least some) children receive in educational settings. PMID:27221370

  1. Effect of seed rate and row spacing in seed production of Festulolium

    Deleuran, L C; Gislum, R; Boelt, B

    2010-01-01

    -type festulolium, Paulita, and in a fescue-type festulolium, Hykor. The objectives were to examine the influence of row spacing (12, 24, and 36 cm) and seed rate (8, 12, or 16 kg ha-1) on plant establishment, development, and seed yield. Observations of autumn and spring in-row plant densities indicated...... satisfactory plant establishment in all combinations of seed rate and row spacing. The number of reproductive tillers was in the range from 800 to 2200 m-2 in Paulita and from 500 to 1300 m-2 in Hykor. Row spacing had an effect on the number of reproductive tillers and in both cultivars the highest number was...... achieved at 12-cm row spacing. Seed yields in the Italian ryegrass type averaged from 1050 to 1150 kg ha-1 and in the tall fescue type from 650 to 800 kg ha-1. Doubling row spacing from 12 to 24 cm had no effect on seed yield in Hykor, while a further increase of row spacing to 36 cm showed a decrease in...

  2. Determining the dissolution rates of actinide glasses: A time and temperature Product Consistency Test study

    Vitrification has been identified as one potential option for the e materials such as Americium (Am), Curium (Cm), Neptunium (Np), and Plutonium (Pu). A process is being developed at the Savannah River Site to safely vitrify all of the highly radioactive Am/Cm material and a portion of the fissile (Pu) actinide materials stored on site. Vitrification of the Am/Cm will allow the material to be transported and easily stored at the Oak Ridge National Laboratory. The Am/Cm glass has been specifically designed to be (1) highly durable in aqueous environments and (2) selectively attacked by nitric acid to allow recovery of the valuable Am and Cm isotopes. A similar glass composition will allow for safe storage of surplus plutonium. This paper will address the composition, relative durability, and dissolution rate characteristics of the actinide glass, Loeffler Target, that will be used in the Americium/Curium Vitrification Project at Westinghouse Savannah River Company near Aiken, South Carolina. The first part discusses the tests performed on the Loeffler Target Glass concerning instantaneous dissolution rates. The second part presents information concerning pseudo-activation energy for the one week glass dissolution process

  3. The product of resting heart rate times blood pressure is associated with high brachial-ankle pulse wave velocity.

    Anxin Wang

    Full Text Available OBJECTIVE: To investigate potential associations between resting heart rate, blood pressure and the product of both, and the brachial-ankle pulse wave velocity (baPWV as a maker of arterial stiffness. METHODS: The community-based "Asymptomatic Polyvascular Abnormalities in Community (APAC Study" examined asymptomatic polyvascular abnormalities in a general Chinese population and included participants with an age of 40+ years without history of stroke and coronary heart disease. Arterial stiffness was defined as baPWV≥1400 cm/s. We measured and calculated the product of resting heart rate and systolic blood pressure (RHR-SBP and the product of resting heart rate and mean arterial pressure (RHR-MAP. RESULTS: The study included 5153 participants with a mean age of 55.1 ± 11.8 years. Mean baPWV was 1586 ± 400 cm/s. Significant (P<0.0001 linear relationships were found between higher baPWV and higher resting heart rate or higher arterial blood pressure, with the highest baPWV observed in individuals from the highest quartiles of resting heart rate and blood pressure. After adjusting for confounding parameters such as age, sex, educational level, body mass index, fasting blood concentrations of glucose, blood lipids and high-sensitive C-reactive protein, smoking status and alcohol consumption, prevalence of arterial stiffness increased significantly (P<0.0001 with increasing RHR-SBP quartile (Odds Ratio (OR: 2.72;95%Confidence interval (CI:1.46,5.08 and increasing RHR-MAP (OR:2.10;95%CI:1.18,3.72. Similar results were obtained in multivariate linear regression analyses with baPWV as continuous variable. CONCLUSIONS: Higher baPWV as a marker of arterial stiffness was associated with a higher product of RHR-SBP and RHR-MAP in multivariate analysis. In addition to other vascular risk factors, higher resting heart rate in combination with higher blood pressure are risk factors for arterial stiffness.

  4. A reduction in growth rate of Pseudomonas putida KT2442 counteracts productivity advances in medium-chain-length polyhydroxyalkanoate production from gluconate

    Zinn Manfred

    2011-04-01

    Full Text Available Abstract Background The substitution of plastics based on fossil raw material by biodegradable plastics produced from renewable resources is of crucial importance in a context of oil scarcity and overflowing plastic landfills. One of the most promising organisms for the manufacturing of medium-chain-length polyhydroxyalkanoates (mcl-PHA is Pseudomonas putida KT2440 which can accumulate large amounts of polymer from cheap substrates such as glucose. Current research focuses on enhancing the strain production capacity and synthesizing polymers with novel material properties. Many of the corresponding protocols for strain engineering rely on the rifampicin-resistant variant, P. putida KT2442. However, it remains unclear whether these two strains can be treated as equivalent in terms of mcl-PHA production, as the underlying antibiotic resistance mechanism involves a modification in the RNA polymerase and thus has ample potential for interfering with global transcription. Results To assess PHA production in P. putida KT2440 and KT2442, we characterized the growth and PHA accumulation on three categories of substrate: PHA-related (octanoate, PHA-unrelated (gluconate and poor PHA substrate (citrate. The strains showed clear differences of growth rate on gluconate and citrate (reduction for KT2442 > 3-fold and > 1.5-fold, respectively but not on octanoate. In addition, P. putida KT2442 PHA-free biomass significantly decreased after nitrogen depletion on gluconate. In an attempt to narrow down the range of possible reasons for this different behavior, the uptake of gluconate and extracellular release of the oxidized product 2-ketogluconate were measured. The results suggested that the reason has to be an inefficient transport or metabolization of 2-ketogluconate while an alteration of gluconate uptake and conversion to 2-ketogluconate could be excluded. Conclusions The study illustrates that the recruitment of a pleiotropic mutation, whose effects might

  5. Biological compost stability influences odor molecules production measured by electronic nose during food-waste high-rate composting

    Composting is a technique that is used to convert organic waste into agriculturally useful products. Composting is an aerobic, solid-state biological process, which typically can be divided into two phases, a high-rate composting phase and a curing phase. High-rate composting plays an important role during the composting process, owing to the high microbial activity occurring during this phase. It requires an accurate plant design to prevent the formation of anaerobic conditions and odors. The formation of anaerobic conditions mainly depends on the rate of O2 consumption needed to degrade the substrate, i.e., the biological stability of the substrate. In this study, we investigated the relationship between the biological activity, measured by the dynamic respiration index (DRI) and the odor molecules production, measured by an electronic nose (EN) during two food-waste high-rate composting processes. Although the O2 concentration in the biomass free air space (FAS) was kept optimal (O2 > 140 ml l-1, v/v) during composting, strong anaerobic conditions developed. This was indicated by the high levels of sulfur compounds, methane, and hydrogen in the outlet air stream. Both the high level of O2 consumption, needed to degrade the high-degradable water-soluble organic matter and the low water O2 solubility, caused by high temperature reached in this stage (up to 60 deg. C), led to the anaerobic conditions observed in the biofilm-particle level. The application of the partial least square (PLS) analysis demonstrated a good regression between the DRI and the odor molecules produced that was detected by the EN (R2 = 0.991; R2CV = 0.990), signifying the usefulness of the DRI as a parameter to estimate the potential production of odor molecules of the biomass

  6. Annual dose rate for Qena governorate population due to consume the animal products

    In this work, the natural radionuclide concentrations of the 226Ra, 228Ra, 232Th and 40K were estimated from samples of cattle and poultry fodder, South Valley University farms and Qena Governorate farm, Qena, Upper Egypt. The radionuclide concentrations and annual consumption rate of twenty-nine animal fodders were analyzed using low-level γ-spectrometer, including a mixture fodder, silage, hay, rice straw, and poultry fodder. The irradiation risk of human health was assessed due to indirect ingestion of the beef, milk, poultry and egg, the annual effective dose of the radionuclides for the local consumer was 2.7, 14, 0.1, and 0.14 μSv ·y-1, respectively. (authors)

  7. Determination of effective cross sections and production rates for tritium in the irradiation experiment TRIDEX

    In the framework of the development of a fusion reactor blanket the irradiation experiment TRIDEX (Tritium Recovery Irradiation DIDO Experiment) takes place at the Juelich Research Reactor FRJ-2 (DIDO). For this equipment the required neutronic calculations have been performed. The aim was the determination of the neutron spectrum and several therefrom derived integral parameters for the irradiation positions in interest. From the calculated effective cross sections for the formation of Tritium resulting from irradiated Lithium samples on one hand and from measured neutron flux densities on the other hand, all needed quantities of the Tritium production could be determined. The calculation of the neutron spectrum has been performed in a two-dimensional x-y-geometry. The neutron flux densities have been gained by gamma-spectrometric measurement of the activities in irradiated activation samples. (orig.)

  8. High-rate volatile fatty acid (VFA) production by a granular sludge process at low pH.

    Tamis, J; Joosse, B M; Loosdrecht, M C M van; Kleerebezem, R

    2015-11-01

    Volatile fatty acids (VFA) are proposed platform molecules for the production of basic chemicals and polymers from organic waste streams. In this study we developed a granular sludge process to produce VFA at high rate, yield and purity while minimizing potential operational costs. A lab-scale anaerobic sequencing batch reactor (ASBR) was fed with 10 g l(-1) glucose as model substrate. Inclusion of a short (2 min) settling phase before effluent discharge enabled effective granulation and very high volumetric conversion rates of 150-300 gCOD l(-1)  d(-1) were observed during glucose conversion. The product spectrum remained similar at the tested pH range with acetate and butyrate as the main products, and a total VFA yield of 60-70% on chemical oxygen demand (COD) basis. The requirement for base addition for pH regulation could be reduced from 1.1 to 0.6 mol OH(-) (mol glucose)(-1) by lowering the pH from 5.5 to 4.5. Solids concentrations in the effluent were 0.6 ± 0.3 g l(-1) but could be reduced to 0.02 ± 0.01 g l(-1) by introduction of an additional settling period of 5 min. The efficient production of VFA at low pH with a virtually solid-free effluent increases the economic feasibility of waste-based chemicals and polymer production. Biotechnol. PMID:25950759

  9. Implications of inflorescence clustering for the visitation rate by hummingbirds and fruit production by Heliconia bihai (L. L. (Heliconiaceae

    Caio César Corrêa Missagia

    2015-09-01

    Full Text Available Plant spatial distribution can influence the activity of floral visitors. Flower clustering in patches may be more attractive to visitors and it supposedly influences the fruit production. This study aimed to test the hypothesis that in Heliconia bihai (L. L. (Heliconiaceae the inflorescence clustering size positively influences the visitation rate and fruit production by the species. The study was conducted at a stretch of Atlantic Forest, in Rio de Janeiro city, Brazil. Five hummingbird species were registered as floral visitors. The average visitation rate (± standard deviation of hummingbirds was 2 (± 0.56 visits per hour per clustering. The amount of inflorescences per clustering positively influenced the visitation rate of hummingbirds, but it negatively influenced the amount of fruits produced per inflorescence. According to the results obtained, we suggest that the density of inflorescences in a clustering may negatively influence the number of flowers visited per inflorescence, due to an increased amount of inflorescences included in the foraging routes.

  10. Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability.

    Randelli, Pietro; Menon, Alessandra; Ragone, Vincenza; Creo, Pasquale; Bergante, Sonia; Randelli, Filippo; De Girolamo, Laura; Alfieri Montrasio, Umberto; Banfi, Giuseppe; Cabitza, Paolo; Tettamanti, Guido; Anastasia, Luigi

    2016-01-01

    Increasing the success rate of rotator cuff healing remains tremendous challenge. Among many approaches, the possibility of activating resident stem cells in situ, without the need to isolate them from biopsies, could represent valuable therapeutic strategy. Along this line, it has been recently demonstrated that lipoaspirate product, Lipogems, contains and produces growth-factors that may activate resident stem cells. In this study, human tendon stem cells (hTSCs) from the rotator cuff were cocultured in a transwell system with the Lipogems lipoaspirate product and compared to control untreated cells in terms of cell proliferation, morphology, stem cell marker and VEGF expression, and differentiation and migration capabilities. Results showed that the Lipogems product significantly increases the proliferation rate of hTSCs without altering their stemness and differentiation capability. Moreover, treated cells increase the expression of VEGF, which is crucial for the neovascularization of the tissue during the healing process. Overall, this study supports that directly activating hTSCs with the Lipogems lipoaspirate could represent a new practical therapeutic approach. In fact, obtaining a lipoaspirate is easier, safer, and more cost-effective than harvesting cells from tendon or bone marrow biopsies, expanding them in GMP facility and then reinjecting them in the patient. PMID:27057170

  11. 2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

    The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO2); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO2 was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 μg C kg-1 d-1). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO2 is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - Highlights: → TNT mineralization is a common feature of natural bacterial assemblages in coastal sediments. → TNT mineralization rates comprised a significant proportion of total heterotrophic production. → These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - The capacity to mineralize TNT ring carbon to CO2 is a common feature of natural bacterial assemblages in coastal sediment.

  12. Improvement of Production Rate of YBCO Coated Conductors Fabricated by TFA-MOD Method

    Nakaoka, K.; Yoshizumi, M.; Usui, Y.; Izumi, T.; Shiohara, Y.

    The metal-organic deposition (MOD) method using trifluoroacetate (TFA) salts is considered to be an effective method for inexpensively fabricating YBa2Cu3O7-y (YBCO) coated conductors with high critical current density property. The long-length TFA-MOD YBCO coated conductors have been fabricated by multi-turn reel-to-reel system. Increasing the thickness per single coating in the multi-turn reel-to-reel system is a cost-effective technique for fabrication of the precursor films in the calcination process since it reduces the number of coatings and shortens the processing time. In this work, we have developed a new starting solution consisting of non-fluorine salts of yttrium propionate and copper 2-ethylhexanoate with focusing on increasing the thickness per single coating for a high-rate fabrication of the YBCO coated conductors by the TFA-MOD method. The critical thickness per single coating of the precursor film fabricated from the new starting solution was improved to 0.44 μm/coat. Furthermore, the addition of diacetoneacrylamide in the new starting solution increased the critical thickness per single coating to 0.79 μm/coat. High critical current of 791 A/cm-width with high critical current density of 2.7 MA/cm2 was obtained using the new starting solution with diacetoneacrylamide at the thickness per single coating of 0.49 μm/coat.

  13. The neutron production rate measurement of an indigenously developed compact D-D neutron generator

    Das Basanta Kumar

    2013-01-01

    Full Text Available One electrostatic accelerator based compact neutron generator was developed. The deuterium ions generated by the ion source were accelerated by one accelerating gap after the extraction from the ion source and bombarded to a target. Two different types of targets, the drive - in titanium target and the deuteriated titanium target were used. The neutron generator was operated at the ion source discharge potential at +Ve 1 kV that generates the deuterium ion current of 200 mA at the target while accelerated through a negative potential of 80 kV in the vacuum at 1.3×10-2 Pa filled with deuterium gas. A comparative study for the neutron yield with both the targets was carried out. The neutron flux measurement was done by the bubble detectors purchased from Bubble Technology Industries. The number of bubbles formed in the detector is the direct measurement of the total energy deposited in the detector. By counting the number of bubbles the total dose was estimated. With the help of the ICRP-74 neutron flux to dose equivalent rate conversion factors and the solid angle covered by the detector, the total neutron flux was calculated. In this presentation the operation of the generator, neutron detection by bubble detector and estimation of neutron flux has been discussed.

  14. ETHANOL PRODUCTION FROM XYLOSE AND WOOD HYDROLYZATE BY MUCOR INDICUS AT DIFFERENT AERATION RATES

    Ria Millati

    2008-11-01

    Full Text Available The fungus Mucor indicus is able to produce ethanol from xylose as well as dilute-acid lignocellulosic hydrolyzates. The fungus completely assimilated 10 g/L xylose as the sole carbon and energy source within 32 to 65 h at an aeration rate of 0.1 to 1.0 vvm. The highest ethanol yield was 0.16 g/g at 0.1 vvm. Xylitol was formed intermediately with a maximum yield of 0.22 g/g at 0.5 vvm, but disappeared towards the end of experiments. During cultivation in a mixture of xylose and glucose, the fungus did not assimilate xylose as long as glucose was present in the medium. The anaerobic cultivation of the fungus in the hydrolyzate containing 20% xylose and 80% hexoses resulted in no assimilation of xylose but complete consumption of the hexoses in less than 15 h. The ethanol yield was 0.44 g/g. However, the xylose in the hydrolyzate was consumed when the media was aerated at 0.067 to 0.333 vvm. The best ethanol yield was 0.44 g/g at 0.067 vvm. The results of this study suggest that M. indicus hydrolyzate can be first fermented anaerobically for hexose assimilation and subsequently continued under oxygen-limited conditions for xylose fermentation.

  15. A study plan for determining recharge rates at the Hanford Site using environmental tracers

    This report presents a study plan for estimating recharge at the Hanford Site using environmental tracers. Past operations at the Hanford Site have led to both soil and groundwater contamination, and recharge is one of the primary mechanisms for transporting contaminants through the vadose zone and into the groundwater. An alternative to using fixed lysimeters for determining recharge rates in the vadose zone is to use environmental tracers. Tracers that have been used to study water movement in the vadose zone include total chloride, 36Cl, 3H, and 2H/18O. Atmospheric levels of 36Cl and 3H increased during nuclear bomb testing in the Pacific, and the resulting ''bomb pulse'' or peak concentration can be measured in the soil profile. Locally, past operations at the Hanford Site have resulted in the atmospheric release of numerous chemical and isotopic tracers, including nitrate, 129I, and 99Tc. Seven study sites on the Hanford Site have been selected, in two primary soil types that are believed to represent the extremes in recharge, the Quincy sand and the Warden silt loam. An additional background study site upwind of the Hanford facilities has been chosen at the Yakima Firing Center. Six tracer techniques (total chloride, 36Cl, 3H, nitrate, 129I, and 99Tc) will be tested on at least one site in the Quincy sand, one site in the Warden silt loam, and the background site, to determine which combination of tracers works best for a given soil type. In subsequent years, additional sites will be investigated. The use of environmental tracers is perhaps the only cost-effective method for estimating the spatial variability of recharge at a site as large as Hanford. The tracer techniques used at Hanford have wide applicability at other arid sites. 166 refs., 41 figs., 16 tabs

  16. Hydrolysis rates, methane production and nitrogen solubilisation of grey waste components during anaerobic degradation.

    Jokela, J P Y; Vavilin, V A; Rintala, J A

    2005-03-01

    Municipal grey waste (i.e. the remaining fraction in municipal waste management systems in which putrescibles (biowaste) and other recyclables (paper, metals, glass) are source-segregated) was manually sorted into six main fractions on the basis of composition and also separated by sieving (100 mm mesh size) into two fractions, oversized and undersized, respectively. In practice, in waste management plant the oversized fraction is (or will be) used to produce refuse-derived fuel and the undersized landfilled after biological stabilisation. The methane yields and nitrogen solubilisation of the grey waste and the different fractions (all studied samples were first milled to 5 mm particle samples) were determined in a 237-day methane production batch assay and in a water elution test, respectively. The grey waste was found to contained remnants of putrescibles and also a high amount of other biodegradable waste, including packaging, cartons and cardboard, newsprint, textiles and diapers. These waste fractions comprised 41%-w/w of the grey waste and produced 40-210 m3 methane (total solids (TS))(-1) and less than 0.01 g NH4-N kg TS(added)(-1) except diapers which produced 9.8 g NH4-N kg TS(added)(-1) in the batch assays. In the case of the two sieved fractions and on mass bases, most of the methane originated from the oversized fraction, whereas most of the NH4-N was solublised from the undersized fraction. The first-order kinetic model described rather well the degradation of each grey waste fraction and component, showing the different components to be in the range 0.021-0.058 d(-1), which was around one-sixth of the values reported for the source-segregated putrescible fraction of MSW. PMID:15491833

  17. CO2 production rate maxima in the deeper unsaturated zone of a semi-arid floodplain at Rifle, Colorado

    Tokunaga, T. K.; Kim, Y.; Wan, J.; Dong, W.; Conrad, M. E.; Bill, M.; Hobson, C.; Williams, K. H.; Long, P. E.

    2015-12-01

    Fluxes of CO2 from soils are important to understand in order to predict subsurface feedbacks to the atmosphere and responses to climate change. Such fluxes are commonly monitored at the soil surface and generally assumed to largely originate within shallow depths. Relatively little is understood on the depth distribution of CO2 production below the rhizosphere. We monitored CO2 fluxes at the soil surface, and measured vertical profiles of vadose CO2 concentrations, matric potentials, and temperatures at the Rifle Site, a saline semi-arid floodplain along the Colorado River in order to determine the significance of deeper vadose zone respiration. Vadose zone CO2 profiles exhibit temperature-dependent seasonal variations, and are consistent with CO2 fluxes measured at the soil surface. The measured vadose zone CO2 concentration profiles combined with gas diffusion coefficients estimated from soil properties indicated that local maxima in rates of CO2 production persist in the deeper vadose zone, about 1 m below the rhizosphere, and above the water table (~3.5 m below the soil surface). We hypothesized that water and oxygen activities, nutrient levels, and temperatures remain favorable for microbial respiration throughout the year in the subrhizosphere, unlike overlying drier soils and the underlying poorly aerated aquifer. Using soils and sediments from the field site, the hypothesized existence of deeper subsurface maxima in CO2 production rate is currently being tested in the laboratory through sediment incubation experiments and in 2.0 m tall vadose zone columns. Initial results from the laboratory support the hypothesized persistence of a subrhizosphere "hot zone" for microbial respiration, partly sustained through seasonal pulses of dissolved and labile organic carbon originating from the rhizosphere. These findings suggest that similar sustained deeper local maxima in respiration rates may occur in many other regions where near-surface conditions are

  18. Secondary charged particle activation method for measuring the tritium production rate in the breeding blankets of a fusion reactor

    In this work, a new passive technique has been developed for measuring the tritium production rate in ITER (International Thermonuclear Experimental Reactor) test blanket modules. This method is based on the secondary charged particle activation, in which the irradiated sample contains two main components: a tritium producing target (6Li or 7Li) and an indicator nuclide, which has a relatively high cross-section for an incoming tritium particle (triton). During the neutron irradiation, the target produces a triton, which has sufficiently high energy to cause the so-called secondary charged particle activation on an indicator nuclide. If the product of this reaction is a radioactive nuclide, its activity must be proportional to the amount of generated tritium. A comprehensive set of irradiations were performed at the Training Reactor of the Budapest University of Technology and Economics. The following charged particle reactions were observed and investigated: 27Al(t,p)29Al; 26Mg(t,p)28Mg; 26Mg(t,n)28Al; 32S(t,n)34mCl; 16O(t,n)18F; and 18O(t,α)17N. The optimal atomic ratio of the indicator elements and 6Li was also investigated. The reaction rates were estimated using calculations with the MCNPX Monte Carlo particle transport code. The trend of the measured and the simulated data are in good agreement, although accurate data for triton induced reaction cross-sections cannot be found in the literature. Once the technique is calibrated with a reference LSC (Liquid Scintillation Counting) measurement, a new passive method becomes available for tritium production rate measurements.

  19. Induction of traps by Ostertagia ostertagi larvae, chlamydospore production and growth rate in the nematode-trapping fungus Duddingtonia flagrans

    Grønvold, J.; Nansen, P.; Henriksen, S. A.; Larsen, M.; Wolstrup, J.; Bresciani, J.; Rawat, H.; Fribert, L.

    1996-01-01

    . Approaching 10 and 35 degrees C the ability to produce traps is gradually reduced. The response of chlamydospore production on agar to changes in temperature is the same as that for trap formation. On agar, at 10, 20 and 30 degrees C D. flagrans loses its trap inducibility after 2-3 weeks. During the ageing...... rate between 15 and 60 mm/week at temperatures between 20 and 30 degrees C. The presence of nematodes induces the fungus to produce traps. The rate of trap formation in D. flagrans has an optimum at 30 degrees C, producing 700-800 traps/cm(2)/2 days, when induced by 20 nematodes/cm(2) on agar...... process, increasing numbers of chlamydospores are produced up to a certain limit. The time for reaching maximum chlamydospore concentration coincided with the time for loss of induction potential. The implications of these results in relation to biological control in faeces are discussed....

  20. Denitrification rate determined by nitrate disapperance is higher than determined by nitrous oxide production with acetylene blockage

    Yu, Kewei; Struwe, Sten; Kjøller, Annelise;

    2008-01-01

    A mixed beech and spruce forest soil was incubated under potential denitrification assay (PDA) condition with 10% acetylene (C2H2) in the headspace of soil slurry bottles. Nitrous oxide (N2O) concentration in the headspace, as well as nitrate, nitrite and ammonium concentrations in the soil...... different treatments. Commonly applied PDA measurement likely underestimates the nitrate removal capacity of a system. Incubation time and organic matter/nitrate ratio are the most critical factors to consider using C2H2 inhibition technique to quantify denitrification. By comparing the treatments with and...... slurries were monitored during the incubation. Results show that nitrate disappearance rate was higher than N2O production rate with C2H2 blockage during the incubation. Sum of nitrate, nitrite, and N2O with C2H2 blockage could not recover the original soil nitrate content, showing an N imbalance in such a...